ANNUAL MEETING OF SME-AIME InCluding programming by the Society of Economic Geologists

ANNUAL MEETING OF TMS-AIME Including programming by Process Technology Division/lSS-AIME Materials Science Oivision/ASM

ANNUAL MEETING OF WOMAN'S AUXILIARY TO AIME

114TH

M

FOUNDED 1811

NNUAL EETING 19S5 NEW YORK CITY

ANNUAL MEETING HOUSING RESERVATION INSTRUCTIONS •

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New York City - - - - - - - - - - - - - - - .

Submit only one request on each form. Additional forms may be obtained by photocopying this sheet. All reservation requests must be in writing and processed through the Housing Bureau. Phone requests will not be accepted. Hotel placement will be made in the order received. Your first choice will be assigned if rooms are available; otherwise you will be assigned to one of your other choices. Rooms will not be held after 6 PM unless a later arrival time has been requested. Failure to indicate a late arrival may result in cancellation of your reservation. Do not send deposits. Deposit information will be sent with your confirmation from the hotel.

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If you need to change either your arrival or departure date. or the

type of room requested. contact the Housing Bureau.

AIME AND SOCIETY HEADQUARTERS A1ME - Hilton Hotel (#1) SME - Hilton Hotel (# 1) TMS - Sheraton Centre (#2) ISS - Sheraton Centre (#2) SPE - Hilton Hotel (# 1) WAAIME - Hilton Hotel (#1)

TECHNICAL SESSION LOCATIONS AIME-New York Hilton SME-New York Hilton TMS-Sheraton Centre and Sheraton City Squire (#3) ISS-Sheraton Centre SME/TMS-New York Hilton and Sheraton Centre

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HOUSING FORM MAIL HOUSING FORM TO: AIME HOUSING BUREAU, clo New York Convention and Visitors Bureau, Two Columbus Circle, New York, NY 10019

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To Ensure Availability and Quoted Rates, Reservations Must be Received by February 3,1985,

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HOTELS Hilton Hotel Sheraton Centre Sheraton City Squire

SINGLE

OOUBLE/TWIN

9~11~12().IJO.I40

12().13~14~15~1115

9~11~120

11~12~135112~14~150

~105

1151125

SUIT~S

TOWERS Hilton Hotel Sheraton Centre

TRIPLE/QUAO·

Single

Double

180

180

175

175

ALL ROOMS SUBJECT TO 8Y4% NEW YORK STATE SALES TAX AND $2.00 PER ROOM PER NIGHT NEW YORK CITY OCCUPANCY TAX. For Special Suite Rates. Contact the Hotel Directly , Student Housing Available: Note: The Housing Form must include the names of all occupants. The Housing Bureau will not assign roommates. NAME _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ____

One Bdrm. 275 & up 275 & up

Two Bdrm. 425 & up 410 & up

2. Type of Room Requested: (Check one) _ _Single -Double _ _Twin _ _ Triple' _ _ Quad' _ _ Suite 3. Room Price Range: $

to

~$______

4. Please provide name(s) of person(s) sharing room:

EMPLOYER _______________________________ , ADDRESS _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ , CITY _. _ _ _ _ _ _ _ STATE _ _ _ _ ZIP _ __

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TEL. NO. (Incl. area code) _ _ _ _ _ _ _ _ _ _ __

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I Arrival Date I Departure Date I

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5. If you would like to guarantee late arrival, you may guarantee your reservation with a major credit card (American Express, Visa, MasterCard). Guarantee by completing the following: Credit Card _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ Card # _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

Choice of Hotels: (Please indicate your 1st. 2nd, and 3rd choices)

Expiration Date _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

1stL_ _ _ _ _ 2nd, ____ --_--_--_3~ _ _

Signature

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IMPORTANT INFORMATION DEADLINE FOR ADVANCE REGISTRATION FRIDAY , FEBRUARY 8, 1985 Please complete the Advance Rag lstration form on the inside back cover and relurn no later than February 8, 1985, to: The Metallurgical Society 01 AIME. 420 Commonwealth Dr., Warrendale, PA 15086. Full payment of registration lees and social function tickets MUST accompany the completed Advance Registration form . For all reg istrations postmarked by February 8, registration packets will be mailed to the individual. Registrants who do nol receive anyth ing by relurn mail should go to the TMS Advance Registration desk at the Sheraton Centre (Sunday through Thursday).

WAAIME A separare check covering WAAIME registration fees and WAA1ME social funct ions sh ould be sent to: WAAIME. 69th Annual Meeling, 345 East 47th St., 14th Floor, New York, NY 10017. Wives must be members 0 1 WAAIME to be entitled to register al the member registrat ion lee. A husband' s member· ship in AIME does not automaticall y make his wile a member 01 WAAIME. For all WAAIME registrat ions postmarked by February 8, registration packets Will be mailed to the individual. Registrants who do not receive anything by return mail should go to the WA AIM E Registrat ion desk at the New York Hilton, On site reg istration for WAAIME will also be conducted a\ the New York Hliion. Please note: Gentlemen are welcome to part ici pate in theWAAIME progra m of social funct ions.

REFUND POLICY If circumstances require you to cancel your TMS regis tration , written notice must be 58nt to TMS, 420 Commonwea lth Dr., Warrendale, PA 15086. postmarked no later than February 15. All tickets tor which refunds are being claimed should be returned wi th your request. WAAIME cancellations should be sent to WAAIME. 69th Annual Meeting, 345 East 47th St.. 14th Floor. New York, NY 10017. NO REFUNDS ON REGISTRATION. SHORT COURSES, OR SOCIAL FUNCTION TICKETS Will BE ISSUED AFTER THE FEBRUARY 15 DEADLINE .

REGISTRATION AT THE MEETING On site registrat ion will be conducted during the lollow ing hours at the New York Hilton and Sheraton Centre: Sunday, February 24 Monday. February 25 TueSday, February 26 Wednesday, February 27 Thursday. February 28

\ · 5 PM 7:30 AM . 4 PM 7:30 AM . 4 PM 7:30 AM . 4 PM 7:30 · 10 AM

PROGRAM BOOKLETS Two program booklets w ill be published; the SME program booklet or the TM S program bookle t will be distributed to individuals as they reg,ster. Both booklets will cont ain information of general interest to the reg istrant, including the A II·lnstitute activities and program.

REGISTRATION POLICY All attendees and authors at the Annual Meeting are required to register. Nonmember authors receive special consideralion and may register at the member rate. Badges are required for admittance to all teChnical sessions and social functiOns .

ADVANCE REGISTRATION DEADLINE: FRIDAY, FEBRUARY 8, 1985

NOTICE: United Airlines selected as the official airline for the 1985 Annual Meeting Cut your travel

costs by 45%. Here's how: 11/1 Uni ted Airlines oilers special air lares, not available to the general public, when you attend the 114th Annual Meeting in New York City and 1ravel between February 21 and March 2, 1985, InclUSive. '" To obtain Ihe 45 ". discount Itom normal coach (Y class) lare with no advance purchase or minimum stay restrictions, simply fo llow these easy s teps: ItIICall United toll·free at 800· 521 ·4041 between 8:30 a.m. to 8 p.m. EST Monday · Friday. l1li Give the special account number 514 M. l1li United specialists will prOVide Inlormation and make reservations tor all !lights and lares, including the special

lUI

UniTED

Annual Meeling lare. The special lare IS available on United flights in the COntinental US. Should your travel originate in a city not served by United, the specialists will assist you in acquiring discounted lares on other carriers lUI United w ill arrange to mail tickets to your home or olllce, or you may purc hase them from your local travel agent (tickets purchased Irom local agents are comm issionable ). "you purchase from a local agent. be sure you or the agent call United' s Convention Oe sk to make your reservation. The special lare is only available through United's Convention Oesk. " Seats are limi ted, so call early lor best availability. Fares are guaranteed at time o t ticket purchase.

Make your reservations today! Call 800·521·4041

TECHNICAL SESSIONS (Preliminary Schedule) SUNDAY, FEBRUARY 24, PM •

Metals & Minerals - Frontier Technology I: Biotechnology - Metals & Environment (SME-MPD) • Financial Evaluation for the Mining Industry (SME-MRMC)

MONDAY, FEBRUARY 25, AM • • • • • • • • • • • • • • • • • • • • • •

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Environmental (SME-Coal). Fillers and Extenders: New Developments in the Field (SME-lndMD) Advanced Techniques in Geochemistry (SME-M&E) Underground Mining New Developments (SME-M&E) Classification in Comminution Circuits I (SME-MPD) Flocculation (SME-MPD) Metals & Minerals - Frontier Technology II: Advanced Pyrometallurgy (SMEMPD) Process Mineralogy - Methodology (SME-MPD & TMS) Strategic and Financial Planning (SME-MRMC) Salts & Brines 85: Technology for Solution Mining Wells, Cavities, and Pipelines (SME-M&E/lndMD) Exploration Strategies for the Year 2000 I (SME & SEG) Advances in Titanium Welding I: Physical Metallurgy & Alloy Stability (TMS) Aluminum Reduction Technology I: Developments (TMS) Deformation I (TMS General Abstract) Electronic & Magnetic Materials (TMS General Abstract) Energy Reduction Techniques in Metal Electrochemical Processes I (TMSI Environmental Control (TMS/SMEMPD) G. R. Fritterer Symposium on Nitrogen in Metals & Alloys I (TMS/ASM-MSD) General Pyrometallurgy I (TMS) Grain Boundaries (TMS General Abstract) Herbert H. Kellogg Symposium: Thermodynamics (TMS) Hume-Rothery Memorial Symposium & Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys I: Hume-Rothery Lecture, Theory of Stability (TMS/ASM-MSD) Mechanical Behavior of Rapidly Solidified Materials I: Processing & Testing Techniques (TMS/ASM-MSD) Mechanical Properties I (TMS General Abstract) Metallurgy of Joining of Materials I (TMS) Modeling in Process Metallurgy I: Fluid Flow Phenomena (TMS/ISS-PTD) Modeling the Effects of Environment on Deformation & Fracture I: Mechanisms & Continuum-Level Models (ASM-MSD) Phase Transformations (TMS General Abstract) Processing Methods & Properties of Advanced Ceramic Materials I (TMS)

• Advances in Grinding Technology (SME-MPD) • Materials Handling (SME-MPD) • Mill Design (SME-MPD) • Mineral Processing and Extractive Metallurgy (SME-MPD & TMS) • Tax and Accounting Issues (SME-MRMC) • Salts & Brines '85: Utilization and Stability of Solution Mined Cavities (SME-M&E/lndMD) • Exploration Strategies for the Year 2000 II (SME & SEG) • Advances in Titanium Welding II: Structure/Property Relationships (TMS) • Alumina & Bauxite I: Alumina Raw Materials (TMS) • Aluminum Reduction Technology II: Alternative Processes (TMS) • Carbon Technology I (TMS) • Deformation II (TMS General Abstract) • Energy Reduction Techniques in Metal Electrochemical Processes II (TMS) • Environmental Control II: Disposal and/or Recovery of Spent Potlining (Panel Discussion) (TMS/SME-MPD) • G. R. Fritterer Symposium on Nitrogen in Metals & Alloys II (TMS/ASM-MSD) • General Pyrometallurgy 1/ (TMS) • Herbert H. Kellogg Symposium: Generall (TMS) • Kinetics I: Ferrous Systems (TMS/ISSPTD) • Mechanical Behavior of Rapidly Solidified Materials II: Iron and Nickel Alloys (TMS/ASM-MSD) • Mechanical Properties II (TMS General Abstract) • Metallurgy of Joining of Materials II (TMS) . • Microbiological Effects on Metallurgical Process~s I (TMS/ASM-MSD) • Modeling the Effects on Deformation & Fracture II: Mechanisms & AtomicLevel Models (ASM-MSD) . • Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys II: Theory of Stability, Electronic & Magnetic Structure (TMS/ASM-MSD) • Processing I: Dissolution & Process Control (TMS/ISS-PTD) • Processing Methods & Properties of Advanced Ceramic Materials II (TMS) • Surfaces & Interfaces (TMS General Abstract)

TUESDAY, FEBRUARY 26, AM • • • • • • • •

MONDAY, FEBRUARY 25, PM

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Managing Natural Resource Companies in Austere Times (AIME AII-Inst. Prog. Comm.) Underground Mining (SME-Coal) Construction Aggregates of Northeastern United States (SME-lndMD) Hydrology (SME-M&E)

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Managing Natural Resource Projects in Austere Times (AIME AII-Inst. Prog. Comm.) Coal Preparation (SME-Coal) Application of Industrial Minerals as Pigments (SME-lndMD) Open Pit Mining: State of the Art (SME-M&E) Classification in Comminution Circuits II (SME-MPD) Exploration (SME-MPD & TMS) Flotation Process Analyses (SMEMPDI Metals & Minerals - Frontier Technology III: Advanced Hydrometallurgy (SME-MPD) Mineral Development Agreements and Economic Rent (SME-MRMC) Salts & Brines '85: Fundamental Studies (SME-M&E/lndMD) Massive Sulfide Carbonate Replacement Deposits in Cordilleran Environments I (SME & SEG) Advances in Titanium Welding III: Process Advances (TMS)

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Alumina & Bauxite II: Bayer Process Development (TMS) Carbon fechnology II (TMS) Energy Reduction Techniques in Metal Electrochemical Processes III (TMS) Herbert H. Kellogg Symposium: Hydrometallurgy & Electrochemistry (TMS) Hydrometallurgy/Chemical Processing I (TMS/SME-MPD) Light Metals - Special Session - Economics, Aluminum Supply/Demand and Energy (TMS) Materials Aspects of Semiconductors & Devices I (TMS) Mechanical Behavior of Rapidly Solidified Materials III: Aluminum Alloys (TMS/ASM-MSD) Mechanical Failure Modes in Nuclear Materials I: Analysis & Experience (TMS) Metallurgy of Joining of Materials III (TMS) Modeling in Process Metallurgy II: Heat Transfer (TMS/ISS-PTD) Non-Destructive Evaluation in Metal Matrix Composites (TMS) Other Light Metals (TMS) Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys III: Thermodynamic Aspects (TMS/ASM-MSD) PhYSical Metallurgy of Electrical Steels I (TMS) Powder Metallurgy of Refractory Metals (TMSI Shear Localization I (TMS) Surface Analytical Techniques for Corrosion Studies I: Overview & Applications (TMS/ASM-MSD) Thermodynamics I: Activity & Free Energy Measurements (TMS/ISS-PTD)

TUESDAY, FEBRUARY 26, PM • • • • • • • • • • • • • • • • • • • • •

Trends and Advances in Microcomputer Application for Natural Resources (AIME AII-Inst. Prog. Comm) Research & Development (SME-Coal) Abrasives (SME-lndMD) Geophysics (SME-M&E) Concentration I (SME-MPD) GAUDIN LECTURE (SME-MPD) Size Reduction, Liberation, and Classification (SME-MPD) Analysis of Risk I (SME-MRMC) Salts & Brines '85: Mineral Recovery (SME-M&E/lndMD) Massive Sulfide Carbonate Replacement Deposits in Cordilleran Environments II (SME & SEG) Advanced Materials as Potential Replacements for Conventional Superalloys (TMS) Advances in Titanium Welding IV: Applications (TMS) Alumina & Bauxite III: Bayer Process Fundamentals (TMS) Aluminum Reduction Technology III: Modeling (TMS) Carbon Technology III (TMS) Energy Reduction Techniques in Metal Electrochemcial Processes IV (TMS) Herbert H. Kellogg Symposium: Generalll (TMS) Hydrometallurgy/Chemical Processing II (TMS/SME-MPD) Kinetics II: Non-Ferrous Systems (TMS/ISS-PTD) Materials Aspects of Semiconductors & Devices 1/ (TMS) Mechanical Behavior of Rapidly Solidified Materials IV: Titanium Alloys, Intermetallic Compounds, & Amorphous Materials (TMS/ASM-MSD)

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Mechanical Failure Modes in Nuclear Materials II: Hydrogen & Environmental Effects (TMS/ASM-MSD) Metallurgy of Joining of Materials IV (TMS) Microbiological Effects on Metallurgical Processes II (TMS/SME-MPD) Microstructure-Property Relationships (TMS General Abstract) Phase Diagrams, Alloy Phase Stability, & Thermodynamic Aspects of Noble Metal Alloys IV: Assessment of Phase Diagrams (TMS/ASM-MSD) Physical Metallurgy of Electrical Steels II (TMS) Recovery Processes in the Secondary Metals Industry (TMS) Shear Localization II (TMS) Surface Analytical Techniques for Corrosion Studies II: A~ueous Corrosion (TMS/ASM-MSD)

WEDNESDAY, FEBRUARY 27, PM • • • • • • • • • • • • • • • •

WEDNESDAY, FEBRUARY 27, AM • • • • • • • • • • • • • • • • • • • • • • • •

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Past, Present and Future of Coal Mine Health & Safety (SME-Coal) Economics of Industrial Minerals (SME-lndMD & MRMC) Geology (SME-M&E) Flotation Fundamentals (SME-MPD) Metals & Minerals - Frontier Technology IV: Support (SME-MPD) Operating Control (SME-MPD) Refractory and Energy Minerals (SMEMPD & TMS) Analysis of Risk II (SME-MRMC) The Mineral Deposit Targets of the Continental Scientific Drilling Program (SME & SEG) Alumina & Bauxite IV: Instrumentation & Control (TMS) Aluminum Reduction Technology IV: Analysis and Control (TMS) Carbon Technology IV (TMS) Cast Shop Technology IV (TMS) Deformation Processing (TMS General Abstract) Energy Reduction Techniques in Metal Electrochemical Processes V (TMS) Extractive Metallurgy of Iron (TMS General Abstract) Herbert H. Kellogg Symposium: Copper (TMS) Hydrometallurgy/Chemical Processing III (TMS/SME-MPD) Fracture I (TMS General Abstract) Lead, Zinc, Tin I: Secondary Processing of Lead & Zinc (TMS) Microstructural Control During Aluminum Alloy Processing I: Deformation, Recovery & Recrystallization (TMS) Microstructural Control Via Powder Metallurgy I (TMS) Modeling in Process Metallurgy III: Metallurgical Processes (TMS/ISSPTD) Phase Diagrams, Alloy Phase Stability, & Thermodynamic Aspects of Noble Metal Alloys V: Selected Experimental Approaches (TMS/ASM-MSD) Phase Transformations II (TMS General Abstract) Physical Metallurgy of High Temperature Alloys (TMS) Restoration of the Statue of Liberty I (TMS/ASM-MSD) Solidification I (TMS General Abstract) Stephen R. Shatynski Memorial Symposium on Surfaces & Interfaces I (TMS/ASM-MSD) Surface Analytical Techniques for Corrosion Studies III: Gaseous Corrosion (TMS/ASM-MSD)

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Coal Surface Mining (SME-Coal) Underground Ventilation (SME-M&E/Coal) JACK LING LECTURE (SME-M&E) Concentration II (SME-MPD) Fundamentals-General I (SME-MPD) Pyrolysis and Agglomeration (SMEMPD) Sources of Funding (SME-MRMC) ~Iumina & Bauxite/Aluminum Reduction Technology- Alumina & Smelting - JOINT SESSION (TMS) Cast Shop Technology II (TMS) Diffusion (TMS General Abstract) Deformation in High Temperature Alloys (TMS) Energy Reduction Techniques in Metal Electrochemical Processes VI (TMS) Environmental Effects (TMS General Abstract) Fracture II (TMS General Abstract) Herbert H. Kellogg Symposium: Iron & Steel (TMS) Hydrometallurgy/Chemical Processing IV: (TMS/SME-MPD) L~ad, Zinc, Tin II: Tin Metallurgy (TMS) Microstructural Control During Aluminum Alloy Processing II: Deformation, R~covery & Recrystallization (TMS) Microstructural Control Via Powder Metallurgy II (TMS) Oxidatio~ (TMS General Abstract) Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys VI: Structures, Transitions & Interrelationships (TMS/ASM-MSD) Processing II: Hydrometallurgy (TMS/ ISS-PTD) Restoration of the Statue of Liberty II (TMS/ASM-MSD) Stephen R. Shatynski Memorial Sym-

posium on Surfaces & Interfaces" (TMS/ASM-MSD) • Solidification" (TMS General Abstract) • Thermodynamics II: Solubility & Interfacial Energy (TMS/ISS-PTD)

THURSDAY, FEBRUARY 28, AM • • • • • • • • • • • • • • • • • •

Coal Utilization (SME-Coal) Economic Benefits of Geomechanics in Practice (SME-M&E) Operations Research (SME-M&E) (Fundamentals-General II) (SME-MPD) Case Studies (SME-MRMC) Paul F. Kerr Memorial Symposium I (SME-MPD& TMS) Alumina & Bauxite VI: Formation & Properties of Alumina (TMS) Aluminum Reduction Technology V: Fundamental Studies (TMS) Carbon Technology V (TMS) Cast Shop Technology III (TMS) Corrosion (TMS General Abstract) Erosion & Wear (TMS General Abstract) Fracture III (TMS General Abstract) Lead, Zinc, Tin III: General (TMS) Microstructural Control Via Powder Metallurgy III (TMS) Non-Ferrous Extractive Technology (TMS General Abstract) Phase Transformations III (TMS General Abstract) Surface Modifications (TMS General Abstract)

THURSDAY, FEBRUARY 28, PM •

Paul F. Kerr Memorial Symposium II (SME-MPD& TMS)

TMS Reception & Dinner Award Presentations TMS and the New York Section have combined their social activities to make a gala affair on Monday, February 25th, highlighted by the TMS Awards Ceremony and New York Section sponsored live entertainment. The evening commences with a reception and dinner in the beautiful Trianon Ballroom of the New York Hilton. At 8:00 PM TMS will bestow its 1985 honors and awards to members of the Society in recognition of their achievements and contributions to the field of metallurgy. Then we will be treated to entertainment "New York Cabaret Style" with an hour show of comedy and song followed by dancing. Everyone is invited to this enjoyable evening. Order your tickets for the combined Dinner-Show on the Advanced Registration Form.

AIME SESSIONS ALL·INSTITUTE PROGRAM This program is tentative in some instances and subject to change. Meeting attendees are urged to check the final program, available at the meeting, for complete information.

L--_M_O_N_D_A_Y_,_F_EB_R_U_A_R_Y_25_,_P_M---I1

L-I_TU_E_S_D_A_Y_,_F_E_BR_U_A_R_Y_2_6_,_P_M----I

MANAGING NATURAL RESOURCE COMPANIES IN AUSTERE TIMES

TRENDS AND ADVANCES IN MICROCOMPUTER APPLICATION FOR NATURAL RESOURCES

Chairman: A.T. Yu, Orba Corp., Fairfield, NJ 07006 201/575-9560 Recession has severely affected the operations and well·being of virtually all of the natural resource companies. This top level session will feature heads of several outstanding companies from each of the four constituent societies of AIME. Each of the speakers will discuss how he and his company managed in these austere times. With varying degrees of emphasis, the following aspects of management will be covered: strategy, planning, organization, finance, marketing, human resources, government relations, and others.

Chairmen: L.M. Kaas, US Bureau of Mines, Washington, DC 20241 202/634-1117 A.T. Yu, Orba Corp., Fairfield, NJ 07006 201/575-9560 The explosive growth of microcomputer production and usage has been one of the most important technological developments in the past decade. It has had in the past, and will have even more in the future, a profound impact on our industry and our lives. Specialists and renowned speakers will review progress and explore trends of this phenomenal segment of industry and how they might affect our present and future.

TUESDAY, FEBRUARY 26, AM Microprocessors In the Minerai Processing Industry: B. W. Burdett and L. B. Hales, Kennecott, Salt Lake City, UT

MANAGING NATURAL RESOURCE PROJECTS IN AUSTERE TIMES Chairman: A.T. Yu, Orba Corp. Fairfield, NJ 07006 201/575-9560 This will essentially be a panel discussion by top level management of some of the world's largest and most prominent engineering/construction firms. Timely topics covered will be: mega versus small, foreign versus domestic, cost plus versus lump sum, cold weather versus desert environment, ecological and regulatory con· cerns, and others. Each panelist will provide a short introduction which will be followed by open discussions. Active audience participation is expected.

The advent of the microprocessor in the 1970s signaled the start of a revolution in the instrumentation and control field. Unlike other control industry changes, however, this one didn't leave the mineral processing industry behind. Due to economic hardships and a gradual recognition by management of the need for control, the mineral processing industry was ready for change when the revolution started. This paper describes how the microprocessor is now being used in analysis, control, and different areas of operator interface in the mineral industry. Particular examples of successful applications will be discussed as well as many that are still in the plan· ning and installation stages. The short· term future of these devices in the industry as well as their long· term potential is also discussed.

SOCIAL HIGHLIGHTS AIME ANNUAL MEETING LUNCHEON The luncheon will be held on Monday, February 25, in the Impe· rial Ballroom A of the Sheraton Centre Hotel followed by the Annual Business Meeting of the AIME Corporation. 1984 President Nelson Severinghaus, Jr., will report on the state of the Institute, and Norman T. Mills, Associate Director, Research Dept., Inland Steel Research, will be installed as 1985 AIME President. The luncheon speaker is Jack E. Thompson, President and Director of Newmont Mining Corp. and its subsidiaries and Chairman of the Board of Newmont Oil Co. and its subsidiaries. He will speak on "Changes in the Natural Resources Industries." Prior to joining Newmont in 1960 as a Staff Assistant, Mr. Thompson was Vice President, Cia. Rayonera Cubana; Vice President and General Manager, Cia. de Fomento Ouimico; Vice President and General Manager, Cia. Ouimico Comercial de Dubs; and Vice President, Cia. Minera Yarayao, all in Cuba. With Newmont, he J. E. THOMPSON became, progressively, Assistant to the

President, Vice President Development, Executive Vice President, Director in 1969, and President in 1974. Mr. Thompson received his education at Colorado School of Mines and Northwestern University. His first job was Geophysics Assistant Party Chief with Independent Exploration Co. in Houston. In addition to his positions with Newmont Mining and Newmont Oil, he is a director of Peabody Coal Co.; Peabody Holding Co., Inc.; and is Vice President of Newmont Exploration Ltd.; Newmont Mines Ltd.; and Newmont South Africa Ltd. Mr. Thompson was awarded the Distinguished Achievement Award by Colorado School of Mines in 1974.

AIME ANNUAL BANQUET The Annual Banquet will take place on Tuesday evening, February 26, in the East Ballroom of the New York Hilton Hotel. Prior to the Banquet there will be a cash-bar reception in the Foyer of the East Ballroom. Black tie is the preferred attire for gentlemen. Dark business suits are acceptable. There will be music throughout the dinner hour. 1984 President Nelson Severinghaus, Jr., will serve as Master of Ceremonies for presentation of the Institute's major awards, followed by a short address by incoming 1985 President Norman T. Mills. We urge you to join us for this very special and elegant occasion.

114th TMS-AIME Annual Meeting TMS-AIME INSTITUTE OF METALS LEcruRE AND ROBERT F_ MEHL MEDALIST Il:4~

a.m.

Wednesday, February 27,1985 Sheraton Cenuc

TMS-AIME LIGHT METALS LUNCHEON

TMS-AIME METALLURGY LEcruRE

12 noon Wednesday, February 27,1985 Sheaton Centre

1:4) p.m. Tuesday, Fe:bruary 26, 1985 Sheraton Centre

Imperial &llroom A

ImpetWI Ballroom B

Imperial &/Iroom 8 Lecturer: Peter Haasen

Speaker: Herbert C. Clough

Professor

Group Vice PreIidenl

University of Gouingen West ~rmany

Alumax, Inc. San Mateo, California

Topic: "The Early Slagel of

Ihe DecompoJition of AUoys" Aboullhe Speaker:; Dr Haasen recdved his diploma in physics and the

TMS-AIME EXTRACTIVE METAllURGY LUNCHEON

EXTRACTIVE

12:00 Noon Tuesday, February 26, She:raton Centre

198~

Imperial Ballroom A Speaker: John F. Elliott

Speaker: Leslie R. Verney

C01l1ulting Engineer Union Minie:re: S.A. Brusse:ls, Belgium

AISI DiltinguiJhed ProfeIsor and Profel1or of Metallurgy Massachusetts Institute of T«hnology

Topic: "Uncenainties Facing the Aluminum Industry "

Topic: "Developments in

Aboul Ihe SPeaker:

Ahout the Speaker:

Ahout Ihe Speaker:

Dr. Verney rceeiv· ~ ed his B.Sc. Honors in Met211urgy from the: Unive:r.... ~ " sity of Wales as wdl as his M.Sc. in 1959 and his Ph.D. in 1979.

Dr. Elliott rece:ived the: degre:e of Bachdor of Metallurgical Engineering from the: University of Minnesota In 1942. and the degree of doctor the Massachusetts Technology in 1949. Profe:ssor Elliott is a membet of the Nation21 Ar2de:my of Engineering of the United States, Honorary Membe:r of the Ame:rcan Institute of Mining. Metallurgical and Peuole:um Enginee:rs, Inc.. 2 Fellow ofTMS-AIME. American Society for Metals. the American Institute of Che:mical Engineers, and of the American Institute of Chemists.

Mr. Clough is responsible for the Primary DiviDr. ref. nat. at sion of Alumax the University of including reduc· Gottingcn. From tion plams in 1954-1956 he was Washington Maryland, a post-doctoral South Carolina, the AI"~u fellow at the 1m,,','"'.' Study of Metals allhe University terest in a new plant in Becan· of Chicago. He is President of cour, Queb«, and the Secon· the Akademie def \Y/isscnschaf- dary Division with plants in Icn in GOltingen. He held Ohio, Indiana and Texas. He: visiting professorships at the has be:en with Alumax and Mellon Institute, Pittsburgh, in Amax, Inc. in various executive: 1963. 2t the Univwity of positions for twenty-five ye:ars, Pennsylvania in 1971, 21 the the: last twe:nty·one: in the: University of Paris XIII in 1978 aluminum business. Mr. Clough and 201 Stanford University in holds a degre:e: in Business Ad· 1984 . He received the Heyn ministration from the Unive:rsity medal of the DeutsChe GesdJ- of Minne:sota and did gaduate schaft fur Metallkunde. work at Columbia Unive:rsity and Ne:w York Unive:rsity.

Copper Extractive Topic: "MetallurgyMetallurgy" An Evolving Technology"

He is a Consulting E~~g:;~~::~:~~ proce:ss technology 2. developme:nt fo r Union Miniere. Metallurgic Hoboken-Overpelt and Mechim . He was Vice Pre:sidem of Metallurgy for Dave McKe:e: Corpor2tion in San Mate:o, served as consultant to AMAX Zamb ia from 1962·1973, Rhodesian Selection Trust Limited from 1%0·1962 and the Mufulia Coppe:r Mines Limited in Rhode:sia from 19)0-1960.

How Can TMS increase

TMS Open Forum

Member Involve:ment?

on

Would you like to Jee Itronger local Julian affilwlion wilh TMS? Would you he in follOr of more regional technical programming? Would you like 10 read more publicationl on new and emerging IechnoiogieI? These and other question!i you may have will be: discusse:d at an open meeting for all TMS members during the Annual Meeting. All TMS me:mbers are invited 2nd urged to attend this open forum where your ide:as and concerns C2n be discusse:d openly and candidly with the: le2dership of the Sc....ie:ty. The: purpose of this forum is to find ways to be:ner me:et the needs of you, the membe:rship, and increase member involve:me:m . The: me:e:ting will be followed by an informal social mixe:r for those who anend. Membe:r involvement is the issue in que:stion . the: answe:r be:gin!i with your participation, so ... BE THERE!

MEMBERSHIP INVOLVEMENT Sunday, Fe:bruary 24,

198~

Venaillel Terrace 7:30 PM The Sheraton Centre New York City Anention Non-members:

complete: a TMS-AlME membership application you have. in addition 10 reg iste:ring for this mee[lng. the opportunity to become: a membe:r ofTMSAIME and recei ve one: full yeu of membership at no addition.al cost.

To take advantage of IhiJ Ipeci41 offer, limply lubmit your TMS-A1ME memherlhip application and your preregislratio~ form to TMS-AIME Headquarten today!

At;" non·me:mber re:gistant attending the

114thTMS AnnualMe:eung, you m2y have credited against your first ye:ar TMS-AlME membe:rship dues, the: financial diffe:rence: between the non-member and me:mbe:r registration fC(:. provided you apply for TMS·AlME membership in conjunction with you r registration . TMS·AIME is providing you, through this spc:cial offer. the opportunity to invest $50 of you r $ 1)0 non-member registration fee 10 cover the: COSt of one full year of TMS· AI ME membership. So. in e:ff«t. by taking a fe:w minutes to

ISS/PTD Luncheon All ISS-AI ME membe:rs are: invited to attend this. the ISS social event of the Annual Me:eting. It is an occasion for the Society to p2y tribute: to some of its d i. stinguished membe:rs and 2ward wmners. Tuesday, February 26, 198) 12:00 noon Sheaton Centre Province: Suite: Ticket price: $25

TMS-AlME Student Housinl Special hOlel room rates have been established for student! at the Sheraton Cenue and Sherawn City Squire. Sec the Housing Form included in this mailer for details on quad rates. To take advantage of the special nudent housing rates, note thu you are a student on your Housing Form. There arc a limited numbcr of hotel rooms at the student rate, 50 s:et your form to the New York Housins: 8ure;lu ell,ly. NOTE: the Housing Form must include the names of all students, the Bureau will not assign roommates.

Student-Faculty Advisors' Mixer

SYMPOSIA HIGHllGHTS LiNfd ~ u.! _ oi dw rympolll whICh • .u tN. prnnIm! N the AIlnu&I N«Im, 1M~ WlU abo tN. atnctM: and ph"nt ~ abHnn ___ to\'a'. m, a bto.d kOp<' oi tuhnKal tnnKh

NilfOFl in Jktab 1M INS IASN·NSD lhnmod,nanua AcImf)' is spoNOfI
MnallWlJ' of Joinina of Maleriab This IJfI'POS'WD ..u (OWCI' the lMlaUu,l3' and tffhnoklcJ oi matcnalo ;ouw., procr-.. Indudfd u.! weldinc oi £mow and nonkm:M alloys. includ,nt

The TMS·AlME Student·Faculty Advison' Mixer will be held on Sunday, February 24. 1985, from 7:00 - 9:00 P.M. in the Regency Ballroom of the Sheraton Centrc Hotel . B«r by the keg will be provided, as well as dry snacks and soda. All TMS students arc invited to attend.

un"""" ....""Q; brum, and toIdnm" mcludint conlinuo!..ll soIcknnc WIth ckcmonic applica.ioot. procatn. lin' f!llen and JOIckn; 1IOl.id.lla.~ bondm,. U>dudint daffusoon bond.nl. ion.beam ml •• mcul/meral. me.allceram" and o.he, in.~tntin& and no;m:l ,nretflCC forllll.ion r«hmqun ; dilfttfd eMrJ\l' ;o;ninc. mcludinl ..,..,. CI«IIon hnm. M'OUAic. and ion bnmI

Student Monitors

PyroaxullUllJ'

Students arc offered the opportunity to defray pan of their Annual Meeting expenses by working as Session Monitors. Each monitor will be responsible for operating audio/visual equipment and for tabulating the number of session attendees for each paper. These: monitor positions arc limited and will be assigned on a first +come basis. If you are interested in working as a Session Monitor, COntact Barbat'2 Kampcrman. TMS-AIME, 420 Commonwealth Drive, Warrendale, PA 15086, telephone 4121776-90~O, no latCf th2.R D«embcr 31, 1984.

T.o nuiolu or,anaed under leoer.1 p)'IOnXUIIuqy .dl to\'a' melulII. tull/II rriin..., PfOCeIICI and ~U.pnxn1 ondud'lII new 1«luuqua 01

TMS-AlME Poster Session Abstracts will be accepted until December 31, 1984 for the TMS·AIME Poster Session at the 198~ AIME Annual Meeting. No formal oral presentation is involved. Each visual presentation is displayed on a 4ft. x 8ft. poster board during the meeting. This medium provides unique opportunity for display of statistical and highly technical subject! for close individual inspection . Abstract! must be submitted on TMS Abstract Form C to: 198~ TMS·AIME Annual Meeting Poster Session. 420 Commonwealth Drive, Warrendale, PA 15086.

F' A ·CT (Facility for the Analysis of Chemical Thermodynamics) A one·day workshop on F· A·C"T is being sponsored by the ASM·MDS Thermody· namic Activity prior to the TMS·AIME Annual Meeting on Sunday, February 24. 1985. A complete information brochure is enclosed with this Advance Mailer. The c05t of the workshop. which includes course notes and other documentation, as well as the workshop luncheon is: $ 95 TMSI ASM Members $125 Nonmembers Please register for this F·A·C·T Workshop on Ihe Advance Registration Form. (Attendance will be limited.)

.raNitft.

n,.

mminc. oaidacOOll.rnilK.inn.

.......... and

conK",uion


IIKUUIrJ

mock-w.,

In eoppe-I.nidcl

11x LCh1 NnaIt ponion 01 .he 191) Annual Propam will IplII mcomput SOl .,..a.t .«hoic&l U,...; Alumina and a.u."e. ull T~. C- Shop. Carbon. Other t.pH NnaII. ~

and Ermronmmlal Conuol. I'Yntntatioot riI tN. ....... .". ltpdwuy and acadnn.. from EuJusK and North Ammr:a. At in the J'U'. mtpbu:iI will lit pIKed on sharuIt new led\noiotiaI information. beth f..odatoxnlal .nd apphed ....ptn will JPM the eRlIR Ip«tNI!I from bmch Ink 10 floU, ~ opc'Qll/II ryscnm • • i,h ackqua.c 1_ aUoncd 10 rtXOUI"aF ~ IItfWttll 1he audorntt and speaker. 11x pn;ourdJnp oi.Ns year', p
..u

......... nu.

Nccha·ioI Beharior 01 Iapid.IJ Solidified

oi ItXefaI 10 the latr mctucbtl& muitlpMR difFwOon. ,.,Itnrtal twfaa ttattionJ. oaidaoon. bot; CWIOIOon. ion implantation. and eouu>p. The J)'lllpoIIUoftI ha~ - " - fnNrina pmIrIICatioas br aoUrafun and COWC,

Rttftl

Pwl

I'tInKh III _

Shalr".

r-..- ..ude"", 01 PTol.

MedaaaiaI Thu

~

sn...,....

..u

Modes in Nadcu IbteriaIs

.,.m.....um. tponICIIC'd ""tJoor nlS/ASW.NSD

Commiflft. is planned .0 prottick a n'¥;'" oi &iIunmoda 01 nudn' ma.crido maa an' primarilynxc:hanic:aI ItI ..IUn: Both in.-iR<:! uod conmbulfd papns ..ill tN. prnnIlfd .. hicb diKv!o thr rft'r:nt 01 ,he,ma! shoc~. h,dtosrn . ....m.ion. and od.n rnwlfOnmrn,al £actOn 011 thcK tllC
m.vus Mt'UlJullJ 01 El«triaI Secdt Thc

In IC, n •• ;on.1 Sympo,ium on PhrSlc.1 " ~ .". the TNS Ferrous MculI"", Conurull« ....1focu. on tht cffC'Ct of mKtosIIUC.un:. compositioa and pcoc","" on the maannic propmia oi dcnnaJ l1«b. It is the aim 01 this I)'lllpoIIWII 10 prottick • fnnIm for .he .mn....a of the uodrrIrm& ph"nJ tnrta.Iluqy prlfl(ipJeI IIIttOhofd in lhe d"dopmchl oi maannic 11C'C1t. Papcn lit dmded inco IW'O 1nlOOI>J. non-onmlfd and ..... n-onmm! clrnlol M~.allu,13' of Elec,ncaJ SoC<'b • ...tlido

.

..u

NiaoAruenu.J Coattol Dwiaa AhamiaWD Alloy Prot::c.ia,: DrdGm.tion. RecowaJ aad lccryIa.lIiutioa 1M papm In .his rympolio,lm ..ill dc:Imbc the drfofllUl.ion/micIOlflue.u..1 eh.,..nC,UIK' and rrorchuucal propmin of aluramum and w-um aJlors U affuud by eoond phaw pando: .u.pn-.. ~~mrntl In ooIulion. I'OOIinuous hot dcfon.tion. warn ....c and ,"",lint ~ and ~ioa.

nor ronlrol 01 ....crwuum....1 £n.wm and the ,mprOw(m~n. of mechaniul p,opc"i~J b, Ihcrmonwchaaol ptOCa5inc will tN. ~. nu. 'ym..... um " ~ br the INS Non·Frrtout

Mnab Commi.1ft

Le.d. Zinc. Tin The Lnd. Zit>c. r ItI ComnuIlCC bao planned J I«hnol ->ont for .Ns mrtU/II . •hich include • JC"f'ICfal sruion on line proms mnaHulIJ and new UKt c.... red by jobn 80uU of National Zt:nc. a JaIion on tin .-.alluqy cIu.urd by i'ctc, Habr.U of Copper PuI ltd . and • snaion on xcondary IftO'frI}' oi Ind and linc: cIu.urd by John Cipn of So Joe Monnall

c..p

Shear loaliutioa

lout •....., sym..... um.

If'CJftKIft'd .".

.he TNS-AINE Ncdwucal MnaIIurIf Commm« and thr T'MS/ASN·NSD Flow and I'Hnutt Commrll«. will fnnat on uaiqur tnt..,. .cdllliqua for m«IIanicaI propcltf clwvtCrUa.lOII. IIIKfOIUUCtURlp,opcn, C'OfftlatioftJ. 0.0.. and f"taauft mcdwIi:smI. ....:I cnttirocmwnlal KIlSIUW", of ... p.dlr ",hdlli«l _mtaIt lton and oiehl. alunuaum and titanIum. amocphous and Ip«iUry alloys lit nanword Emphuat ..u lit on muhanoc-al ptnprnon aft'rnfd .". the IIlI(IWUUaUrai lnlurn mull1tlJ rrom .."od .IOlidifintinn

..u

Eaap itcdtKtioa Tcd:laiques ia Mna! ElecttcdK,"iol

~

01 INs sa _ I)'mpollllm. INS Ei«uol,.i( PIOC"," Commill«. is .0 brin& abou. a cohrotw d-.on oi thr ddfnmt m:hnoqUC'J tha. could tN. used .0 reduc~ .he CMrJ\I' ~UlRtllCnl in mnaI rlennxheminl procnon. Papen: on IIIIR oi dw lin and romplnfd ranrch indudm, pRo and poII.1n:almtnl oi clrmolyrc dUI;"""'. n:plattmcn. of rlennxMminl rnnions .". chcminl In<.tioN. im~mcnu ItI nlrrrni ondtutriod dectrolJtic dcYica and «julpmrn •• objrn~

.po~

Th(' Sleph('a R. SbaIJ •• ki M('morial SrmpolilUD 011 Swfaa:s aDd Iatafacet Thu I)'mpolium 00 Sud-=< uod In~ "'1

.~

LiPt JIetab

The

new co.U cksi&no for tn\pfOI'ni _ Inruport, Ckcuo-lMltIJ power reduction mnhodI. uod p&nd d-.....on "'" amona lhe - " - .0 lit prarnrfd

b,

.h~

The Shapinc and Fnrrninc Cocnnur.tcC of"JltS.. AIWE is spoNIOIUII twO - " - on Sbcar ",",Iop'_ Ow..,. Nna.l Dri"OIIDIOuon. n.ar ~ Oral wnh both lftKfOIIIUCIuraI u weU .. CCIOdIDUWll up«u oi 0.0.. Ioaliut_ in shear .. it ocrun IG _b _ u rronal I"omuna. meW nlllint. beUiAia and fa.1JUC fat.i1lR. Nnhodt of pmlininc and prnrnlm, ....... local...."'" ..u tN. addraocd &om a nnrt)' oi nrwpoonu Thor conaequrnus 01 Ws faiIun: mode .IIh ~prd .0 £orraablh" .. xrticc propmors will abo

.........

1ht Habcn H. KdJoa SympoIiIUll 011 &uwb1'C Nnallurp

~~:":~":::!'~ NICki, CobaI •• and PttciouJ Nnw CommrIlCCS u, tnbutr 10 ProlaIor H H. ~Ilna:', J'U' and COll.inu11II conrribu.ioot in.his forlel. 1M SympoIium ..dl prondc a f..wn 10 ' " ' " ' the Nm'ft. R"~ oi n ..auift lMlall"", WIth rcsprct 10 YNIOUI pn... ,,,clud,n, thctmod,nanua and w.c.ia. u ~lacfd fO hydrornclall"", and PJfOIIIrIalluqy. SettrnJ ...d.o" ..dl prao:nl in£orraarion on Rttftrlr cornpIettd -."II u well u diKuWoru 011 .n.procrcas •..,...m,

Hiatt T cmpctI(UfC .wo,. 1M Hllh T mIpUIl...., A..". Cornmotln. r i M ~ 111m: ~ on ru,n lemprnl...., p i l\II'biM svpm.JIofI 11w flnt ... Ph.,..... MnaIIutaY r:I HIJh Ten>plmlr...., Allop" wdl ha~ (QOIUlbullonl
marrnab .... h _ "unun". hllh ,~ utaruunI ano,.. CUIDfICI'IIC'. and (~ UI rcpbciftc ..pcnIkIJI ~ Coauol Via Poo.da- MnaBlItJJ A Ihrcc IInIion ~. (Oo~ b, thoPowdH NnalharJr and Sobcf,fnuon COOlVIUUCft r:I TNS-AINE... 10 M Iwld ., nlnJ"nnion wnh thtI Annual N~"'I 11w t)1IIpOIIWII ••11 trnp/>ulu 1110. "'"'" br .hich ~ powOn proc"""'l (&II be ultd 10 tnhlllcc miUO""Utl" .. 1
..:I........'"'

more ..,......,$11:

'clat~ip ~ ~ in

both fltkil and 10 prowMk • two.d IIUt 01 the an upd.le on PfOIIUI In Ihll "'''"'1 aIpC"CI 01 powdn mctallut" .

NictobioJoaiaJ Effccu

Oft

Nm.llu....i(ll!

"-

TIt. m.n...J1DfK.....n. JPOIIIOftd br thor TNSISltE

Ph,... prow_

H,dlomcllllull,ICbem".1 PIOCemnl Jo.nl Conomllltt and thor Doc,"",II, c.om.m.un., ..u be Iwld 10 oaformauon 011 nuTftll rcwsrdI ~ and dft«_ for thor role cl t-.cnooIlfCOU 1ft ahcr .... lIICtaIkqxalln(.t_. The ntapbaM .. 011 thor .pccJ"1<. Id«tlft ........., cl booo:hnD..:aI tcKtioaI omooInnc .,.,II1&II IftIlIfIaII and bKtmaI 80th dnadnI Iaboracory .udin and 0IIftIIftnCiaI appbcata. _ 10 M d..uDnI Tcd>ftxaI.

ncs

acmu

at

~

_II u

faaon .... be ...h.ockd

"-

~ ...ci ... Eftl. . . . NccaI Nauix CompOIua

III

T~

thor

for

Techtuqucs fOf channUII.... f\a.., In pIft\ItU" rnalmM and aItIIIOWalfd conlpollm ..u be die 1Ubjm. cl tho ..... CompwlICI ~lnI _kick boron fibn- n:infortnl tJumu,UIlI. pplmc fibnn:mf'orcnI alurrunum and "con carbt!k l*1ocu.1ara n:lnIOKCd "um.nutll Acouf,lic ( m.....IO(I. I.n, ...... hod •• uk_I< lechtuqUCS. and .....r.tt Kowua .ill be dw.:u-d U poI"nlill CbatlC1enUlion technoques llul""lDfIO'Ium II ipOIIIOI'nI br Uw TNS Compolil" N'IC"NB c.omnuClft"

Moddiata lhc EIF«a of EAftrocuneal Dd'ormat... ud

OQ

'18t"hft 11w TNSI ASN.NSD t«NuraIlClmc,. "CompuICf

Sun.. Ia"on in

Wac~

$amtt", .IpON«UIII

IWO-

~ ..,.mrarum 011 1M 1Ut.,ec:1. "WooXIinc 1M Effects of EM'~111 on OcfOfnoallon and Fmmuc " Ten ",...cd 1IflCUcn, &II cl ~ _ npmI III nnow I:If>l'ttI cl ~dm.J

onocIduac ...

be mWnc prnmIUIOftl Nodr:q lCudin from both .~ aod _llIIUum poonu cl ..... _ mdudnI In addaioa. dfuu cl • broed

cl

_ _ nbed. phua. a q _ . ., , _ aod Ioqwd 1nn2b. The~. 10 prcocnuac raWa of Ih ..1t I« .... t fC"Ku(h. PI~tck tubac .... "al bac:kJrouad mfornoauon. '" • IUtOrial fuluon. 10 la, 1110. fvundUIOll for thorw -.klmc apprwdI Surfaa: AnatyricaI Techmqua for ConoIioa

IpUU\lIII

~

...... U pROW

~II

in..w.uoa

.......mm: _

.. n.ItOrlm .. nu Topic att... ,nch,de
UId

eonJUIUOII

mKIOkopy .....,

clthor

tomIIOOII raIIIatII(

cl

phlllod"'"on 'pen/Okop,.

IItUICIdary "'" I11III SPUI"*"P1....... .,.,U1'*'1'J'. foI.Inn lransform lnfntcd IIp<
.wo,. ci lhc Nobk Ncuh

The fon!ocomonc I)'mpIIMUIII 011 thor "Alloy. cl Noble- Mnaa" II berne ~ br thrtt lKhnnI amunmCft-TNS Ano, !'hun. TMSIASN·MSD Ph.,c D'I,f.m, .nd Ibe Tb .... rnod,".m ... Commnln.s Thif $ftDpWIUIft .,11 _ _ 01 6 !cr:hl"liad _ nth omooInnc .4.) A..". 01 mppcr. olhocr and aoId ...~ bccrI Ind~ n:ptdnI .. I taOOIC pound oI!hcona that .... ..lor phuc . .hil..., and phuc d.-pm rdauonslupl Al thor 1JfIlPONUI'I, thor 'I'l1IOIII upcru cl 1""'_", atC:I ..u be diaru.nI br mntthm amn,dr -kine: on dlifncnl upcru cl pbuc cI!a&r-. (rysW JlNallftS. phuc dynacna and Ihcona cl 11w fmt _ .ill hi: thor Humc·Rorhcry lcnUft br Dr I W._ cl 1110. Brookha_ lIbonlOl)' .ho II 1M nmml fUlpotftl cl dw AIWE Humc.ltothcry Awacd. SubRquc-nl speake" ... UtoI'ft ""...... ow !opia .,,!al"'l 10 tla:lfOIIO< lheorlltl. order. diMwdct ph.-1IOIIlCIUI and pIwc lI...aonnallOftl. mcuun:1TIm1 01 tlx cla:uonoc lU\IClun:, _bibl, cl mcl"loc I"". thctmodrlWlU( mca.wcITlmU, phuc cUaalltll dC"n:rrDlnlllOll and mod.-Imc. "loy (rysW fII\IC"IUfCII and _ ...... OIM IIIHIUrcmcnU and phuc rd..lO<..tups thai malt JPCOf'nUy 10 the Nobk Nnal

1ImICd....,.

"loy""

.nor

AI..,.

Ph,..

Chemi.try ud oflktab c..r...... IIlIICmII ' " fltld.... .lIkllplud III!' in ....., appI..,....... Il!ducI.int IOIDponcng n... propnua cl acI-m (CBIIU( rrtatcndt 1ft -r dcpcndr:n. upon procntUlf: mnhodJ and fabnmJOll l«ftarquft UII'd 10 pn:lCluu dw flllll

Rl\ImI'"

I....

componcnI

ThrI _

br thor TNS

~m. ~

and Ph,.... cl WnaII Commtlftt, ..u 011 I -O
ron.

Proa.M~

Tlw TMSISWE}omI "-"- NuwnIotr ConIauttu io JfXIftIOtinc 7 I0600nt .. thor A ........ MenU'll orhith includC"' I) Nethodolasr· lecml ~~ l)MoncraI Pnxmina and Enratu... NnaU","; Jl &pIDnlioa~ ..) PrKIOUI Net .... Gold. smcr and reM. "EonJJ. 1tdnc:10I)' and ludu."aI NIIItUII; 6 and 7) Paul , KCIf N~ Sympollum. EtnpNu cllhc papm .ill be 011 .a-n mack Ihtou&h thor \IX cl procnI rruncralosr. A Paul F K(1f SympIIIIWII Pnxccd"",

..0 M publllhnl

Materials AIpectI of Scmicoaductoa _

DnXa The objm.M cl

m. rwo _

"....,....- •

10

mnaIIurcxaI ~ and _malt ICWM_ ..me cl 1M hlJhblJh" cl thO" CIIIftDl mardi

rJpoK

10 ICIrnllltl UI cla:lfOIIO< nwmalo. II woO _ _ only cl "",1lUI .,...., and will CO'I'(I the PftCIF"UIIOII be ........ 01 o:.rJCfI III adonIOI and ,a nnuf_ 011 ..Ia:triral and JU\ICIUfaI dwactcr_. sptnOdaI dccompouuon IQ 1nGa.W' rpotaDLI ..,and III dfcm on (Ia:triral ~. cllhmMl ~ '" .be lJel'Chuon 01 dllloa"oOll ;0 "cr-c ctyR.LII. and IaIdr _ lIIIpIanWlOll datnap- III ~ and ,a llI\IIC"aIint bma .....

ph.,......

"*

HiAory .ad

AtchtoIos,

_-day J'fftIPO'IUIII on thor pmmI mlOQI_ cl 1110. Sn.1\IC cl Lrbm, II be"" OI~ br thor ASNJNSD Commi".... on thO" "'-orr and ~ clNatrnalt wrth the coopcnl... cl dw U. S NIbOII&I Pvk Smoou Spnfta from I'ranu and lbe UIUIfd Scam will diKwl 1M OflJlnal dnIp and mamu. thO" ooncblion cllhe S!.I~ aft« nnrly 100 JUtI '" Nc-w YOf~ Hubor. and thor .tpl 10 mlOft n n... poI'.bilu, cl • OIlCmbm only IOLII 01 thor rmorlIllO(I _kohopo 011 Libm, IWand wu IlOl loN..mnt br A

Thll 1)'fD.,-um . .--d br Uw TNS/MSD Corroeoon and Enorwonmcntal Eft"tm Commotfft". wdJ rorw on 1M appbc-o.uon cl .....)'txal Icr:hlloques for 1M dim"! _ ' " cl ...nan d.-lJIIoIbuon Of modifouon •• raull cl ~ 10

ptOCnt

surUa mod.ronl lftalmals. IImIIl"d and cO'Mnbu,rd prcI'CftllUOlll ..u d _ 1M '* cl fttlOUIlfIIIIlI)'t1ClJ tec:hnoques IIl.udy IOfIOIIOO IIICIucbnc AUf" dm.roa

.... -

Nc:w Ti dc:s fro m T MS BFTA mANIUM IN THE 1980'S • Edited by R.R. Boyer and H .W . Roscnbera Procttdln" o( a symposium held at the 1I21h AIME Annual Mttt ina in Atlanta. GeorCia. March 8. 198) HaroXO\'cr. )06 I»,a. illwu::lIed. ind" M$
EM8R11Tl..EM£NT BY THE LOCAllZID CRACK ENVIRONMENT • Edited br R P Ga.n,loff. PIOCtt(hnas o( a sympos.um held at the TMS·AIME fall Mtttina In Ph,ladtlph" , Ptnnsyl......... Oct • • 2-6. 1983. H..dbac:~ . <1.92 !»Ia. ilhutral"d. indat. M$2<1..00 • 5 $1<1..00 • lUlOO fATIGUE CRACK GROWllt ntRESHOID CONCEPTS • Edtted br D. Da.idson ::and S Surcsh. Procttdlnp of, symposium hdd"" the TMS·AI ME hli Mtttina In Philaddphl•• Pc:nnsyl..,ni,. Octobc-r 3·). 1983 . Hard(oY(r. )6) I»Sa. illuslratcd. indo. • S $ I7.00 • Ll B .OO M $3).00 FERRIn C AllOYS FOR USE IN NUCllAR ENERGY TECHNOLOG IES . Edited by J.W. Davis .nd OJ . Michel. ProcttdirlCs o( Ihe Topical Con(crence held at Snowbild. Utah, June 19·23. 1913. Hardc
M . AIME Member pri(e S· AIME Studenl pri(c: L · lisl price

MARK YOUR CALENDAR NOW! FUTURE 1985 TMS·AIME MEETINGS TMS·AIME NORTHEAST REGIONAL MEETING May 1-3, 1985 Allied Corporation Morristown, New Jersey This is the first meeting in an on-going series of Regional Meetings. Topics

of the Northeast Regional Meeting will review the State of the Art in the field of Rapidly So l idified Crystal li ne Alloys, including Fundamentals, Ribbon and Powder Processing, Consolidat ion and Applications of Rapid Solidification Processing to various Alloy Systems such as Aluminum, Titanium, Magnesium, Iron, Nickel, and Copper Base Alloys. Microcrystalline Brazing and Magnetic Alloys will also be covered. Invited topics and poster session; attendance is limited to 200.

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TMS·AIME INTERMOUNTAIN REGIONAL MEETING June 2-4, 1985 Snowbird Ski and Summer Resort Snowbird, Utah This meeting focuses on important aspects of evaluating precious metal ores. General Sessions with invited speakers, panel discussions and a field trip to Getty's Gold Mine wil l feat ure some of the highl ights.

ICCMV

FIFTH INTERNATIONAL CONFERENCE ON COMPOSITE MATERIALS (ICCM V) July 29 - August 1, 1985 Town and Country Hotel San Diego, California Papers on all aspects of theoretical and experimental technology of composite materials and structures. Glass, graphite and boron fibers, and organic, metal and ceramic matrices and other const ituent materials are to be included. Panels and exhibits will be included in the program to provide opportunities for interact ion through stimulat ing discussions of prob lem areas or chal lenges and future trends. A proceedings of the conference will be available. TMS·AIME EXTRACTIVE AND PROCESS METALLURGY FALL MEETING November 10-13, 1985 Hotel Inter-Continental San Diego, California International Complex Sulfides Symposium---Processing of Ores, Concentrates, and By-products. The papers are invited on plant operations, econom ics, process design & new technology, basic science, process mineralogy, beneficiation, hydrometallurgy, pyrometallurgy, electrometallurgy, and environmental control. Abstracts are due January 15, 1985. TMS·AIME EXTRACTIVE AND PROCESS METALLURGY FALL MEETING December 1-4, 1985 Marriott's Harbor Beach Hotel Ft. Lauderdale, Florida International Symposium on Recycle and Secondary Metals. The papers at this symposium will cover the following major area: industrial practice and fundamental research i n aluminum; iron and steel; lead, copper, and other scrap; processing and refining waste recovery; metals recovery from municipal waste. Abstracts are due February 1, 1985.

For further Information on any of these meetings, please contact the TMS Meeting Department. Meetings Department TMS·AIM E 420 Commonwealth Drive Warrendale, PA 15086 (412) 776·9050

NEW YORK SECTION'S

CABARET NIGHT Monday, February 25, 1985 Enjoy an evening of entertainment featuring a 12·piece orchestra and BIG NAME entertainers immediately following the Society dinners. *

Julius LaRosa

June Valli

Julius LaRosa has emerged from the television image of the smiling boy next door to become a worldly and compelling performer who leaves an indelible imprint on a song and a disquieting effect on an audience. Presenting an unexpected blend of controlled excitement and easy self-confidence, LaRosa is, in the words of one writer, an "in" singer. He is "appreciated for his canny knack of handling the words ... his swinging approach ...his general awareness of what a song is REALLY about." Born in Brooklyn, NY, on Jan. 2, 1930, LaRosa enlisted in the Navy and in 1950 was transferred to the United States Naval Band. A group of his Navy buddies engineered his audition for Arthur Godfrey. Godfrey hired LaRosa when he was released from the Navy in 1951. The singer became a coast to coast favorite and after his much-publicized split with Godfrey his star continued to rise. In recent years he has divided his time between the theatre, recording, and singing appearances. His theatre credits include "West Side Story," "Be"s Are Ringing," "Come Blow Your Horn," "Kiss Mama," "Carousel," and "What Makes Sammy Run." His two recent albums are "Hey Look Me Over" and "You're Gonna Hear From Me."

June Valli, the "Hit Parade" girl of the 1950s treats audices to a chronological hit parade of pop tunes from "Green Eyes" to "Nine to Five," with some riotous comedy-song routines along the way. Both Valli and Jim Merchant, her husband and musical partner, have mastered the art of mesmerizing their audience. Merchant is a wizard with the alto sax, blowing out tunes like a man possessed, bringing the saxophone back to its glory days of the 1950s. The term "hit parade" is almost synonymous with Valli, as she spent several years on television's popular "Lucky Strike Hit Parade" in the early 1950s, singing other performers' top songs of the week. But then, in 1955, Valli had the pleasure of being able to sing her own hit on the the program-"Crying in the Chapel." *Cabaret Night will be held in the East Ballroom of the New York Hilton following the Society Dinners from 9:30PM-1:00AM. Ticket prices are as follows: Cabaret Night only $15 or $10 if bought in combination with one of the Society Dinners. Tickets may be purchased by filling out the advanced registration on the inside back cover.

SME·AIME SHORT COURSES (All SME-A/ME Short Courses WiII.Be Conducted at the New York Hilton.)

INTRODUCTION TO MICROCOMPUTERS Saturday and Sunday, February 23·24,1985 (SME·AIME) This short course will provide a basic understanding of microcomputer concepts and terminology. The course is intended for minerals professionals and managers who wish to understand microcomputers and how they may be used in minerals organizations. Many of the topics covered in this course will contain information that is directly applicable to minicomputers and mainframe (large scale) computers as well as microcomputers. No previous background in computers or data processing is required. All materials used in the course will be provided. The course will describe hardware components of a typical microcomputer system. Software fundamentals are explained and the major programming languages and operating systems for microcomputers are introduced. Typical software packages for both general use and minerals applications are demonstrated. Gllidelines for selection of microcomputers are presented along with comparative costs of popular systems. In addition to a textbook and class notebook, each registrant is provided with a per· sonal computer for continuing self study after the short course.

the Mineral Processing Section. The course fee is $325 for AIME members and $450 for nonmembers. • Part II will be conducted on October 14·15,1985, prior to the 1985 SME-AIME Fall Meeting, Albuquerque, New Mexico.

PROFESSIONAL ENGINEER EXAM DATES States have the option of administering the professional engineering exam on one of three days each year. Following is an exam schedule for the remainder of the decade. For the specific date and location of the exam in your State, contact your State registration board. 1985 - October 24·26 1988 - October 27·29 1986 - October 23·25 1989 - October 26·28 1987 - October 29·31 1990 - October 25·27

ECONOMIC EVALUATION Saturday and Sunday, February 23·24,1985 (SME·AIME)

An outline of the course follows: I) Microcomputer Hardware: Central Processing Unit, Memory Storage, Peripheral Equipment, and Telecommunications Interface; II) Microcomputer Software: Operating Systems and Programming Languages; III) Microcomputer System Development - Doing It Yourself: Problem Definition, Flowcharting, Introduction to Programming in BASIC, and Data Management Concepts; IV) Microcomputer Applications Packages - Preprogrammed: General Purpose Packages (Electronic Spreadsheets, Data Base Management, Word Processing, Business Graphics, Statistical Analysis, and Accessing Commercial Data Bases), Minerals Applications (Contour Mapping, Geochemistry/Geophysics, Ore Reserves and Geostatistics, Mine Planning, Equipment Analysis, Mine Ventilation, Flowsheet Design, Financial Analysis), and Applications Demonstrations; and V) Guidelines for Selecting a Microcomputer: Selection Criteria - A Check List, System Configuration, and System Costs.

This course covers the subjects presented in the five-day "Economic Evaluation" courses taught on the Colorado School of Mines campus several times each year by Dr. Frank Stermole. While the five-day course places considerable emphasis on how to calculate as well as how to use discounted cash flow analysis criteria, the two-day course places primary emphasis on the proper use of discounted cash flow analysis criteria for correct managerial economic decision·making in different evaluation situations. This course will be oriented heavily toward case study economic analysis of income or service-producing investment situations. DCFROR, Net Present Value, and Present Value Ratio analysis will be emphasized but other discounted cash flow analysis techniques will also be discussed. Previous experience in working with discounted cash flow calculations and economic decision-making is very desirable but not necessary background for participants to benefit from the course.

The primary course instructor will be L. Michael Kaas, a registered professional mining engineer with over 20 years experience in mining computer applications. He is Chief of the Division of Minerals Information Systems of the US Bureau of Mines. Prior to joining the Bureau, he directed mining industry programs for the IBM Corporation. He has conducted numerous seminars on mineral industry computing and is currently lecturing on microcomputers in the Washington, DC, area. J. P. Stone, Assistant to the Chief, Division of Minerals Information Systems of the Bureau of Mines, will assist Kaas. The course fee is $525 for AIME members and $650 for nonmembers. (Note: The cost of the course includes a $200 equipment charge.)

Dr. Frank Stermole is professor of mineral economics and chemical engineering at Colorado School of Mines, Golden. He is a well-known lecturer and author of "Economics Evaluation and Investment Decision Methods," with accompaning problem solutions manual. The course fee is $425 for AIME members and $550 for nonmembers. (Note: The cost of the course includes the textbook and problem solutions manuaL)

PROFESSIONAL ENGINEER REVIEW COURSE IN MINING ENGINEERING, PART 1* Saturday and Sunday, February 23·24,1985 (SME·AIME) This course is designed for experienced engineers with a knowledge of mining problems who wish to review typical exam problems in preparation for the nationally uniform mineral engineering examination for professional engineering licensing. Participants will find a calculator helpful. Topics for day one include Mining Methods and Unit Operations, Mineral Exploration and Evaluation, Coal Preparation, and Engineering Economy. Topics for day two include Mine Investment Analysis, Mineral Processing Flow Diagrams, Mine Ventilation, and Surface Coal Mine Systems Design. The course instructors, all from The Pennsylvania State Univer· sity, will be Jan M. Mutmansky, associate professor of mining engineering; R. V. Ramani, professor of mining engineering and chairman of the Mineral Engineering Management Section; and Peter T. Luckie, professor of mineral processing and chairman of

SURFACE SUBSIDENCE ENGINEERING Saturday and Sunday, February 23·24, 1985 (SME·AIME) This course is designed to introduce the state-of-the-art knowledge about the elements of surface subsidence and its effects on surface structures and ground water due to under· ground mining. Day one lectures will cover characteristics of surface movements, theories of surface movements, prediction of surface movements in surface structural damages, protective measures for surface structures, structural damages and their protective measures over abandoned mined lands, and dewater· ing of ground water. The second day will be devoted to case studies including subsidence monitoring, surface subsidence characteristics, surface structural damages, and ground watering dewatering in longwall mining, room-and·pillar mining, and abandoned mines. In each case, prediction and actual occurence will be correlated. The effectiveness of various methods of preventing structural damage employed will be discussed. Course instructors are Syd S. Peng, professor and chairman of the Dept. of Mining Engineering, West Virginia University, Morgantown; Abdul Wahab Khair, associate professor of mining engineering at West Virginia University; and W. H. Su, research assistant professor at West Virginia University. The course fee is $325 for AIME members and $450 for nonmembers. Limited to 20 participants.

TMS-AIME SHORT COURSE F*A*C*T (Facility for the Analysis of Chemical Thermodynamics) Sunday, February 24, 1985 (TMS-AIME) A one-day workshop will cover the application and operation of the F * A * C * T Thermodynamic Computer System. F * A * C * T is a state-of-the-art user friendly computer system which enables performance of common thermochemical calculations with the aid of a terminal. The programming incorporates extensive prompting understandable by those with a background in the principles of chemical thermodynamics. Moreover, all the input is extensively checked for logical and numerical validity. Although the system was conceived to be of particular value to those engaged in chemical metallurgy, the scope of the system is such as to be of use in any branch of applied physical chemistry. The use of F * A * C * T does not require the prior knowledge of any computing language. What can F.A.C.T do? By using one or more of the F.A.C.T programs together with the F.A.C.T data base or your own data. you can: display. in a format suitable for appending to a report. thermodynamic data and the references on over 3800 compounds (program INSPECT); search the data base to find all the compounds that could be formed from a given set of up to 8 alements (prog. INSPECT); calculate property changes (liH,liG, etc) for any isothermal/isobaric or non-isothermal/non-isobaric chemical reaction (prog. REAC-

TION); perform any type of industrial heat balance in as much detail as desired (prog. REACTION); enter, store in a private data base and use in the F.A.C. T programs your own thermodynamic data (prog. OATAENTRY); determine the vapour pressure of any element or compound (prog. REACTION); determine the overall equilibrium composition of an ideal gas mixture containing up to 8 elements and 99 species (prog. EOUILIB); perform isothermal isobaric (or isovolumetric) heterogeneous equilibrium calculations including aqueous systems (prog. EOUILIB); calculate and plot E-pH (Pourbaix) diagrams for aqueous systems containing up to 5 elements (prog. EPH); generate isothermal predominance (stability) diagrams for systems containing up to 5 elements (prog. PREDOM); calculate and display temperature-composition binary phase diagrams for any system from free energy data supplied by the user (programs BITERM and PO:rCOMP); calculate an.d d!splay on the Gibbs-tril!.ngle a temperature-, composition ternary phase diagram from thermodynamic data supplied by the user (prog. TERNFIG); calculate from free energy data supplied by the user and display a composition "square" temperature-composition diagram for a reciprocal salt system (prog. RECIPFIG); perform least-squares regression analysis of solution data taking into account the Gibbs-Duhem equation (prog. FITBIN); and perform coupled optimization of binary thermodynamic and phase diagram data (prog. FITBIN). In most cases the output is suitable for appending to a report thus eliminating error-prone costly and time-consuming intermediate typing or drawing F.A.C. T should assist research workers, educators and students in the fields of engineering and applied chemistry.

Sponsored by the ASM-MSO Thermodynamic Activity, the workshop leaders are A. O. Pelton and C. W. Bales, professors of metallurgy at Ecole Poly technique de Montreal, Canada, and W. T. Thompson, associate professor of metallurgy at the Royal Military College, Kingston, Ont., Canada. Cost of the workshop is $95 for AIME-ASM members and $125 for nonmembers. Attendance is limited to 100. To be given in the Regency Ballroom of the Sheraton Centre, New York.

FIELD TRIPS Sunday, February 24; Thursday, February 28; Friday, March 1, 1985 (Registration is limited on these trips as indicated below.) SUNDAY, FEBRUARY 24

FOSSILS OF FIFTH AVENUE The walking field trip will leave from the Lobby, 30 Rockefeller Center, at 10:00 AM and 2:00 prJ! for this half-day tour, repeated in the morning and afternoon, Sunday, February 24. Sidney Horenstein, Oept. of Invertebrate Paleontology, American Museum of Natural History, will conduct the tour, beginning at 30 Rockefeller Plaza with a view of the 450-million-year old ancestors of the Chambered Nautilus and c'jflcluding ...lith a look at 100million-year old fossils embedded in the walls of Tiffany's. Participants will discover that Fifth Avenue is a cornucopia of fossils and building stones from around the world. Mr. Horenstein will talk about how the different building stones were formed, how they were quarried, and the various roles they have played in the earth's history. The tour will be held in rain, snow, or shine, so plan to bring warm clothing. Tickets for the field trip are $10 per person and may be purchased by filling out the advance registration form on the inside back cover. Return to Tiffany's, Fifth Ave. and 57th St., will be at 11 :30 AM and 3:30 PM. There is a limit of 30 persons per half-day trip. THURSDAY, FEBRUARY 28

NEW YORK FINANCIAL DISTRICT TOUR Buses will leave the New York Hilton Hotel at 12 Noon, Thursday, February 28, and will return at 5:00 PM. It is not uncommon to hear New York City referred to as the financial capital of the world. The Economics and Finance Subsection of the New York Section has arranged a brief yet intensive tour of the New York Stock Exchange, the Federal Reserve Bank of New York, and the New York Commodity Exchange. Visit to the Stock Exchange will include a self-explanatory theater presentation on the Exchange, a questions and answer period, and a visit to the gallery overlooking the trading floor. Tour of the Federal Reserve Bank will provide visitors with an overview of the bank's operations and some insight into its role in the economy. After a brief introduction, participants will visit the currency processing division, the protection area, and the gold vault. The Comex tour will include a brief oral presentation purposely timed to coincide with the opening or closing of the precious metals pits viewed from the gallery. Tickets for the field trip are $15 per person and may be purchased by filling out the advance registration form on the inside back cover. The trip will be held rain, snow, or shine, so plan to dress accordingly;

business clothes are appropriate. There is a limit of 30 persons for the tour. FRIDAY, MARCH 1

NEW YORK FINANCIAL DISTRICT TOUR This is a repeat of the Thursday tour. Buses will leave the New York Hilton Hotel at 8:00 AM, Friday, March 1, and will return at 1:00 PM. Tickets for the field trip described below left are $15 per person and may be purchased by filling out the advance registration form on the inside back cover. There is a limit of 30 persons for the tour.

NEW JERSEY ZINC COMPANY (STERLING MINE) LIMESTONE PRODUCTS CORP. (LIME CREST OPERATION) TRIP The field trip on Friday, March 1, will run simultaneously with one trip starting with the Sterling Mine of New Jersey Zinc Co., and the second one with Limestone Products Corp.'s Sparta, NJ, plant and quarry. Buses for both trips will leave the New York Hilton Hotel at 6:30 AM and will return about 4:00 PM. The New Jersey Zinc visit at the Sterling Mine will start with a review of the ore-body model and a brief talk with slides of this unique deposit of zinc minerals. Mining methods to be viewed in an underground inspection tour will include both cut-and-fill stopes and undercut-and-fill pillars using LHO's and conventional slushing. Haulage is on track with battery locomotives. Stop two on one tour and stop one on the other will be the Limestone Products Corp.'s Sparta, NJ plant and quarry. This quarry has been in operation for over 60 years and currently supplies over 150 products, spread among four major market segments. The field trip will focus on LPC's product mix and marketing program. Participants will see how this company has modified their production and marketing emphasis in order to keep pace with both increased competition and socioeconomic change in the marketplace. Warm clothing; warm, rubber, steel toed boots; and hardhats with lamps are required. There is likely to be some underground ladder climbing. Tickets are $25 per person, including box lunch, and may be purchased by filling out the advance registration form on the inside back cover. There is a limit of 80 persons for the twosegment field trip, 40 persons per bus.

WAAIME SPONSORED SOCIAL FUNCTIONS LADIES AND GENTLEMEN ARE WEL.COME TO ATTEND ALL SOCIAL FUNCTIONS SPONSORED BY WAAIME. MORNING COFFEE, MONDA Y THRU WEDNESDAY 8 A.M.-tO A.M. Please join us for a complimentary continental breakfast at the WAAIME Hospitality Room at the New York Hillon Hotel, Mercury Rotunda, Ballroom Floor.

SUNDAY, FEBRUAR Y 24, 1985 BRUNCH AT THE FABULOUS RAI NBOW RO OM AT ROCKEFELLER CENTE R

Selecllrom menu, ' Sealing only at 11 :30 A.M. Tickets: $25.00. OVERVIEW TOUR OF MANHATTAN A deluxe motor coach lour. A wonderful way to become acquainted with the many aspects of thiS small island . 1 :30 P.M.-S:OO P.M. Tickets: $15.00:' MONDAY, FEBRUAR Y 25, 1985 BRIDGE LESSONS WITH THE MASTEA Tannah Hirsch, bridgewriler and editor. One lesson at I 0:30 A.M .. plus lesson with play 01 hands at I :30 P.M. Rms. 517-520. NY Hilton Hotel. Tickets: $20.00. MUSEUM OF MODERN ART Includes a lecture on the new MaMA, a visit to the archives and a conducted tour 01 the current exhibit. Limit 01 40 10:30 A.M.-I :30 P.M. Tickets $15.00.

TUESDAY, FEBRUARY 26, 1985 NEEDLEPOINT Dorothy Kaestner, designer, author and international judge. Rms. 517-520 NY Hilton Hotel. 10:00 A.M.-II :30 A.M. Tickets: $13.00. GUCCI Sip champagne a~ you view the famous LaGatieria titled with Dr. Guccrs private art collection and one 01 a kind pieces of jewelry. luggage, handbags and clothing. Limit 01 50. 9 :30 A.M.-ll:30 A.M. Tickets : $17.00. ANNUAL LUNCHEON Lunch in the beauti ful and lamous Tavern on the Green in Central Park. After lunch. be entertained by mUSIC Irom Broadway. - 12:00 P.M.-3:oo P.M. Tickets $45.00. WEDNESDAY, FEBRUARY 27, 1985 LOWER EAST SIDE SHOPPING A guided tour to the bargain capital 01 the world. 9 :30 A.M.-I :oo P.M. Tickets: $23.00: ' NY TIMES TOUR WITH LUNCH AT SARDI' S After. tour. meet an editor or leature writer lor a question and answer period. Then Sardi"s lor lunch.' Walk to Cats orother theatre performance. 10 :30 A.M.-l :3O P.M ... • Tickets : 541.00. CATS WAAIME has available a number 01 tickets lor this award-winning mUSical. Matinee beginS at 2:00 P.M. Tickets: $40.00.

FUR S AND JEWELS In a luxurious fur showroom. meet one 01 New York 's most prestigious lurriers and a well-known Jewelry designer. 9:30 A.M.-I :oo P.M. Tickets: $25.00: '

WAAIME BUSINESS MEETINGS: New York Hilton Hotel Rendezvous Trianon Ballroom Floor

Monday

Tuesday Wednesday

9 :00AM 10:30AM 2:00PM 3:00PM 4:00PM 9 :00AM 9:00AM

Engineers lor Tomorrow Scholarship Loan Fund WAAIME Board Meeting Delegates Meeting Delegates-Board Wine Reception WAAIME Round Table WAAIME Annual Meeting

Cash bar available .. Buses depart and return 54th SI. NY Hilton Hotel One-way bus only - does not return 10 hotel

On-S ITE REGISTRATION : New York Hilton Hotel. 2nd Floor, Sunday 1-5 P.M.: Monday 8 A.M.-4 P.M. ; and Tuesday 8 A.M.-12 Noon.

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REGISTRATION: WAAIME MEMBERS AND NONMEMBERS ADVANCE REGISTRATION DEADLINE : 2/10'85 Badges and tickets will be mailed to advance registrants whose lorms are postmarked by that date. PLEASE NOTE : Mail registration form and chec k payable to : WAAIME 1985 Annual Meeting 345 East 47th St .. 14th Floor New York. NY 10017 Name: MrJMrs. -;;;;;--_ _ _ _ _ _ _ _ _ _ _ __ tSpou... .......,

SOCIAL FUNCTIONS : Members and Nonmembers mu.1 be regl.tered to purc ha. e ticket •. One regl.trant may p urcha.e mo re than on e IIcket : "' Tickets: _ BrunCh _ Overview Tour _ Bridge Lessons _ Museum of Modern Art _ Furs & Jewels _ Needlepoint _ Gucci _ Luncheon _ lower East Side _ NY TimesiSardi"s _ Cats

$25.00 $15.00 $20.00 $15.00 $25.00 $13.00 $17.00 $45.00 $23.00 $41.00 $40.00

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REGISTRATION FEES: Membership in AI ME does not automatically make the spouse a member of WAAIME. $12.00 WAAIME Member Nonmember $15.00 $.

$!-::==

II WAAIME Member, Give Name 01 WAAIME Section

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ADVANCE REGISTRATION Photocopy this l arm il ad ditional forms are needed. No refund s Issued alter February 15, 1985. Firs! Name

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M.lliorm and payment, by February 8, 1985, to : Annual MeetIng, The Metallurglca' Society, 420 Commonwealth Dr., Warr endale, PA 15086. f I

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FIELD TRIPS

AIM E Member. SME·AIME TMS·AIME ISS-AIME SPE·AIME Student Members

• Tlc~els Su nday, Fa bruary 24, 198 5 _ Fossils of Fifth Avenue·l0 AM, $10 _ Fossils 01 Fifth Avenue·2 PM, $10

FA·F S Fp·F 5

Thursday, Fabrua ry 28,1 985 _ NY Financia l District Tour, $ 15 _ NJ ZINC Co.lLimestone PrOducts Corp., 525

NF·F $ LP.F S_

'$100 'Xl '''0

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$100

SM

Free

ASM Members Members, Founder Societies Nonmember Author

ASM

SEC

SEC

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$100 $100 $100 $100 $100

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Mining Met~lIurgy

Iron & Steel Pelroleum

SHORT COURSES Saturday and Su nday, February 23·24, 1985 Introduction to Microcomputers (SME), $525 AIME Members: $650 Nonmembers P.E, Review Course In Mining Eng ineeri ng, Part 1 (SME), $325 AIME Membe!s: $450 Nonmembers Economic Evalua tion (SME), $425 AIME Members: $550 Nonmembe!s Surface SubSidence Engineering (SME), $325 AIME Members: $450 Nonmembers Sunday, Febru ary 24, 1985 F' A 'C'T (Fac ility for the Analys is of Chemical Thermodynamics TMS), $95 AIMEiASM Members: $ 125 Nonmembers

MC·S$ _ PE·SS EE·SS SS·SS

FA·SS _

PUBUCATIONS ORDER AIME AIME Oty. Title Membar St udant $42.00 $21 .00 Beta Titanium in the 1980's Embrlttlemen1 by t he Localized Crack $24.00 $ 14.00 Environment Fatigue Crack Growth Thresho ld $35.00 $ 17.00 Concepts Feffit ic Alloys for Use in Nuclear 540.00 $20 ,00 Technolog ies High Conductivity Coppe! and Al uml· num Alloys " '.00 $18.00 $48.00 524.00 Li ght Metats 1985 Modet ing of Casting and Welding Processes II $30.00 $15.00 Phase Transfo!mations In Feffous 525,00 $15.00 Alloys PhySica l Chemistry of Extractive Metallurgy 547.00 523 .00 Second International Conference on Metallu,gical Slags and Fluxes 546.00 $23.00 $45.00 $22.00 Superalloys 1984 Titanium Net·Shape Technologies $38.00 $19.00

Non· Mambar $63 ,00 $38 ,00 $53.00

."

_

SOCIAL FUNCTIONS • T l c~el' Sunday, Fa bruary 24, 1985 FS·R $ _ _ Finance SympOSium Wine/Cheese Reception, 5:30 PM, NY Hilton, $20 Mond ay, Fabruary 25, 1965 AM ·l $ _ _ AIME, Annual Meeting Luncheon, Noon. Sheraton Cent re, $28 SM·O $ _ _ S ME·AIME Dinner, 7:00 PM, Hil ton, 535 _ SME·AIME Dinner/Caba ret Nig ht, Hilton, $45 SM·C$ TM·O $ _ TMS·AIME Dinner, 7:00 PM, Hilton, 535 TM·C $ _ TMS·AIME Dinner/Cabaret Night, Hilton. $45 SP·O $ _ SPE·AIME Olnner/Aecp., 6:00 PM, Hilton, $35 SP·C$ _ SPE·AIME Dinner/Cabaret. Hilton, $45 _ NY Sec tion Cabaret Nigh t Only, CN ·O $ _ 9:30 PM, Hilton. $15 Tues day, Fabru ary 26, 1985 CO· L S _ Coa l Div. Luncheon, Noon, Hi lton, $25 EM·l $ _ Extractive Metallurgy Luncheon, Noon, Sheraton Cen tle, $25 IM·L5 _ _ _ Industrial Minerals Oiv./MRMC Luncheon, Noon, Hilton. $25 IS·L5 _ _ _ ISS·AIMEJPTO Luncheon, Noon, Sheralon Centre, $25 MM·L$ _ _ Mining & Metallurgica l $oclety of America Luncheon , Noon, Hilton, $25 AIME Annual Banquet, 7 PM. Hillon (In(llvld"al Ilcket holders m.y , It wMre they wiSh. On ly futlla!)tes wltl be feserv&d ,1 _ Individual Tickets, $5O_ _ Table (to), $500 AB· B $ W&dnasda y, Febru ary 27, 1985 SG·B $ _ Society of Economic Gao logists Breakfast, 7:30 AM, Hi1ton, 522 lM·l $ _ Light Metals luncheon, Noon, Sheraton Centre, $25 ME·l $ _ Mining and Exploration Div. Lunc heon, Noon, Hilton, $25 MP·l $ _ Mine'al Processing Dlv. luncheon, Noon, Hilton, $25 ADVANCE REGISTRATION GRAND TOTAL $

$SO.OO $55.00

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TMS-AIME Annual Meeting Program - 1

114th AIME ANNUAL MEETING TECHNICAL SESSIONS The numbers in bold type on the left of each session title indicate the page on which that session is listed in the Annual Meeting Technical Program. Sessions will be in the Sheraton Centre Hotel, the Sheraton City Squire and the Hilton Hotel. Page 46 3

18 33

47 19 34 48

61 77 93 4

19 48 62 94 20

34 49 62 95 63

78 95 96 4

21 79 63

78 5 6

22 35

49 65

80 7 7

23 81 97

106 65 66

82 98 8

23 9 24

10 11 24 36 50

67 83

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37 51 68 84

25 51 69 85 99

Code: Sheraton Centre Hotel - SCH Sheraton City Squire - SCS Hilton Hotel - H

Session Title Day/Room/HoteJ Advanced Materials as Potential Replacements for Conventional Superalloys ....................................... Tues. PM, Province Ste (SCH) Advances in Titanium Welding I: Physical Metallurgy & Alloy Stability .............................................. Mon. AM, Jefferson Ste (SCS) Advances in Titanium Welding II: Structure/Property Relationships .................................................. Mon. PM, Jefferson Ste (SCS) Advances in Titanium Welding III: Process Advances ..................................................................... Tues. AM, Jefferson Ste (SCS) Advances in Titanium Welding IV: Applications ............................................................................ Tues. PM, Jefferson Ste (SCS) Alumina & Bauxite I: Alumina Raw Materials .............................................................................. Mon. PM, Royal Blrm B (SCH) Alumina & Bauxite II: Bayer Process Development ....................................................................... Tues. AM, Royal Blrm B (SCH) Alumina & Bauxite III: Bayer Process Fundamentals ..................................................................... Tues. PM, Royal Blrm B (SCH) Alumina & Bauxite IV: Instrumentation & Control ....................................................................... Wed. AM, Royal Blrm B (SCH) Alumina & Bauxite/Aluminum Reduction Technology: Alumina & Smelting Joint Session ..................... Wed. PM, Royal Blrm A (SCH) Alumina & Bauxite VI: Formation & Properties of Alumina .......................................................... Thurs. AM, Royal Blrm B (SCH) Aluminum Reduction Technology I: Developments ...................................................................... Mon. AM, Royal Blrm A (SCH) Aluminum Reduction Technology II: Alternative Processes ............................................................ Mon. PM, Royal Blrm A (SCH) Aluminum Reduction Technology III: Modeling .......................................................................... Tues. PM, Royal Blrm A (SCH) Aluminum Reduction Technology IV: Analysis & Control.. ............................................................ Wed. AM, Royal Blrm A (SCH) Aluminum Reduction Technology V: Fundamental Studies ........................................................... Thurs. AM, Royal Blrm A (SCH) Carbon Technology I ........................................................................................................ Mon. PM, Georgian Blrm A (SCH) Carbon Technology II ....................................................................................................... Tues. AM, Georgian Blrm A (SCH) Carbon Technology III ...................................................................................................... Tues. PM, Georgian Blrm A (SCH) Carbon Technology IV ...................................................................................................... Wed. AM, Georgian Blrm A (SCH) Carbon Technology V ..................................................................................................... Thurs. AM, Georgian BIrm A (SCH) Cast Shop Technology I ..................................................................................................... Wed. AM, Georgian Blrm B (SCH) Cast Shop Technology II .................................................................................................... Wed. PM, Georgian Blrm B (SCH) Cast Shop Technology III ................................................................................................. Thurs. AM, Georgian Blrm B (SCH) Corrosion ....................................................................................................................... Thurs. AM, Washington Ste (SCS) Deformation I ....................................................................................................................... Mon. AM, Colonial Rm (SCS) Deformation II ...................................................................................................................... Mon. PM, Colonial Rm (SCS) Deformation in High Temperature Alloys .................................................................................... Wed. PM, Province Ste (SCH) Deformation Processing ........................................................................................................... Wed. AM, Colonial Rm (SCS) Diffusion .............................................................................................................................. Wed. PM, Jefferson Ste (SCS) Electronic & Magnetic Materials ........................................................................................... Mon. AM, Georgian Blrm A (SCH) Energy Reduction Techniques in Metal Electrochemical Processes I ................................................ Mon. AM, Versailles Blrm (SCH) Energy Reduction Techniques in Metal Electrochemical Processes II ............................................... Mon. PM, Versailles Blrm (SCH) Energy Reduction Techniques in Metal Electrochemical Processes III .............................................. Tues. AM, Versailles Blrm (SCH) Energy Reduction Techniques in Metal Electrochemical Processes IV .............................................. Tues. PM, Versailles Blrm (SCH) Energy Reduction Techniques in Metal Electrochemical Processes V ............................................... Wed. AM, Versailles Blrm (SCH) Energy Reduction Techniques in Metal Electrochemical Processes VI .............................................. Wed. PM, Versailles Blrm (SCH) Environmental Control ................................................................................................. Mon. AM, Commonwealth Rm (SCH) Environmental Control I ..................................................................................................... Mon. AM, Imperial Blrm B (SCH) Environmental Control II: Disposal and/or Recovery of Spent Potlining (Panel Discussion) ................ Mon. PM, Imperial Blrm B (SCH) Environmental Effects ........................................................................................................... Wed. PM, Diplomat Rm (SCH) Erosion and Wear ...........................................................'................................................... Thurs. AM, Colonial Room (SCS) Exploration ...................................................................................................................... Tues. AM, Rhinelander North (H) Extractive Metallurgy of Iron ............................................................................................... Wed. AM, Dominion Rm B (SCH) Fracture I ................................................................................................................... Wed. AM, Commonwealth Rm (SCH) Fracture II .................................................................................................................. Wed. PM, Commonwealth Rm (SCH) Fracture III ............................................ : ................................................................... Thurs. AM Commonwealth Rm (SCH) G. R. Fitterer Symposium on Nitrogen in Metals & Alloys I ............................................................. Mon. AM, Consulate Ste (SCH) G. R. Fitterer Symposium on Nitrogen in Metals & Alloys II ........................................................... Mon, PM, Consulate Ste (SCH) General Pyrometallurgy I. ........................................................................................................Mon. AM, Province Ste (SCH) General Pyrometallurgy II ........................................................................................................ Mon. PM, Province Ste (SCH) Grain Boundaries ................................................................................................................. Mon. AM, Royal Blrm B (SCH) Herbert H. Kellogg Symposium: Thermodynamics ....................................................................... Mon. AM, Regency Blrm (SCH) Herbert H. Kellogg Symposium: General!. ................................................................................. Mon. PM, Regency Blrm (SCH) Herbert H. Kellogg Symposium: Hydrometallurgy & Electrochemistry .............................................. Tues. AM, Regency Blrm (SCH) Herbert H. Kellogg Symposium: General II ................................................................................ Tues. PM, Regency Blrm (SCH) Herbert H. Kellogg Symposium: Copper .................................................................................... Wed. AM, Regency Blrm (SCH) Herbert H. Kellogg Symposium: Iron & Steel .............,................................................................. Wed. PM, Regency Blrm (SCH) Hume-Rothery Memorial Symposium & Phase Diagrams, Alloy Phase Stabililty & ......................... Mon. AM, Versailles Terrace (SCH) Thermodynamic Aspects of Noble Metal Alloys I Hydrometallurgy/Chemical Processing I ........................................................................................ Tues. AM, Senate Ste (SCH) Hydrometallurgy/Chemical Processing II ....................................................................................... Tues. PM, Senate Ste (SCH) Hydrometallurgy/Chemical Processing III ...................................................................................... Wed. AM, Senate Ste (SCH) Hydrometallurgy/Chemical Processing IV ...................................................................................... Wed. PM, Senate Ste (SCH) Kinetics I: Ferrous Systems .................................................................................................. Mon. PM, Dominion Rm B (SCH) Kinetics II: Nonferrous Systems ............................................................................................ Tues. PM, Dominion Rm B (SCH) Lead, Zinc, Tin I: Secondary Processing of Lead & Zinc ................................................................ Wed. AM, Princess Blrm (SCH) Lead, Zinc, Tin II: Tin Metallurgy ............................................................................................ Wed. PM, Princess Blrm (SCH) Lead, Zinc, Tin III: General .................................................................................................. Thurs. AM, Princess Blrm (SCH)

2 - TMS-AIME Annual Meeting Program 37 37 52 12 26 38 53 39 54 13 27 85 14 28 40 54 29 55 69 86 70 87 100 56 105 15 40 71 16 29 41 101 42 88 106 107 11 30 42 57 72 89 16 72 102 43 58 73 43 30 90 17 31 105 58 105 44 59 74 91 75 91 45 60 76 103 32 45 92

Light Metals: Special Session--Economics, Aluminum Supply/Demand & Energy ............................. Wed. PM, Imperial BIrm A (SCH) Materials Aspects of Semiconductors Materials & Devices I: Oxygen in Silicon .................................... Tues. AM, Princess Blrm (SCH) Materials Aspects of Semiconductors & Devices II: Miscellaneous Topics ........................................... Tues. PM, Princess Blrm (SCH) Mechanical Behavior of Rapidly Solidified Materials I: Processing & Testing Techniques ..................... Mon. AM, Regency Foyer (SCH) Mechanical Behavior of Rapidly Solidified Materials II: Iron & Nickel Alloys .................................... Mon. PM, Regency Foyer (SCH) Mechanical Behavior of Rapidly Solidified Materials III: Aluminum Alloys ...................................... Tues. AM, Regency Foyer (SCH) Mechanical Behavior of Rapidly Solidified Materials IV: Titanium Alloys, Intermetallic ....................... Tues. PM, Regency Foyer (SCH) Compounds, & Amorphous Materials Mechanical Failure Modes in Nuclear Materials I: Analysis & Experience ........................................... Tues. AM, Monarch Rm (SCH) Mechanical Failure Modes in Nuclear Materials II: Hydrogen & Environmental Effects .......................... Tues. PM, Monarch Rm (SCH) Mechanical Properties I .......................................................................................................... Mon. AM, Monarch Rm (SCH) Mechanical Properties II ......................................................................................................... Mon. PM, Monarch Rm (SCH) Mechanical Properties III ................................................................................................... Wed. PM, Georgian Blrm A (SCH) Metallurgy of Joining of Materials I ........................................................................................ Mon. AM, Washington Ste (SCS) Metallurgy of Joining of Materials II ....................................................................................... Mon. PM, Washington Ste (SCS) Metallurgy of Joining of Materials III ...................................................................................... Tues. AM, Washington Ste (SCS) Metallurgy of Joining of Materials IV ...................................................................................... Tues. PM, Washington Ste (SCS) Microbiological Effects on Metallurgical Processes I ............................................................. Mon. PM, Commonwealth Rm (SCH) Microbiological Effects on Metallurgical Processes II .......................................... "................. Tues. PM, Commonwealth Rm (SCH) Microstructural Control During Aluminum Alloys Processing I: Deformation, Recovery ....................... Wed. AM, Monarch Rm (SCH) & Recrystallization Microstructural Control During Aluminum Alloys Processing II: Deformation, Recovery ....................... Wed. PM, Monarch Rm (SCH) & Recrystallization Microstructural Control Via Powder Metallurgy I ....................................................................... Wed. AM, Regency Foyer (SCH) Microstructural Control Via Powder Metallurgy II ...................................................................... Wed. PM, Regency Foyer (SCH) Microstructural Control Via Powder Metallurgy III ................................................................... Thurs. AM, Regency Foyer (SCH) Microstructure - Property Relationships ................................................................................. Tues. PM, Dominion Rm A (SCH) Mineral Processing & Extractive Metallurgy ............................................................................. Mon. PM, Rhinelander North (H) Modeling in Process Metallurgy I: Fluid Flow Phenomena .......................................................... Mon. AM, Dominion Rm A (SCH) Modeling in Process Metallurgy II: Heat Transfer .................................................................... Tues. AM, Dominion Rm A (SCH) Modeling in Process Metallurgy III: Metallurgical Processes ....................................................... Wed. AM, Dominion Rm A (SCH) Modeling the Effects of Environment on Deformation & Fracture I: Mechanisms & .............................. Mon. AM, Diplomat Rm (SCH) Continuum-Level Models Modeling the Effects of Environment on Deformation & Fracture II: Mechanism & .............................. Mon. PM, Diplomat Rm (SCH) Atomic Level Models Nondestructive Evaluation in Metal Matrix Composites .................................................................. Tues. AM, Province Ste (SCH) Non-Ferrous Extractive Processing Technology ......................................................................... Thurs. AM, Regency BIrm (SCH) Other Light Metals ........................................................................................................... Tues. AM, Georgian Blrm B (SCH) Oxidation ............................................................................................................................. Wed. PM, Colonial Rm (SCS) Paul F. Kerr Memorial Symposium 1.. ................................................................................... Thurs. AM, Rhinelander North (H) Paul F. Kerr Memorial Symposium II .................................................................................... Thurs. PM, Rhinelander North (H) Hume-Rothery Memorial Symposium & Phase Diagrams, Alloy Phase Stability & .......................... Mon. AM, Versailles Terrace (SCH) Thermodynamic Aspects of Noble Metal Alloys I Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys II: ............. Mon. PM, Versailles Terrace (SCH) Theory of Stability, Electronic & Magnetic Structure Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys III: ........... Tues. AM, Versailles Terrace (SCH) Thermodynamic Aspects Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys IV: ............ Tues. PM, Versailles Terrace (SCH) Assessment of Phase Diagrams Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys V: ............. Wed. AM, Versailles Terrace (SCH) Selected Experimental Approaches Phase Diagrams, Alloy Phase Stability & Thermodynamic Aspects of Noble Metal Alloys VI: ............ Wed. PM, Versailles Terrace (SCH) Structures, Transitions & Interrelationships Phase Transformations I ..................................................................................................... Mon AM, Dominion Rm B (SCH) Phase Transformations II. ........................................................................................................ Wed. AM, Jefferson Ste (SCS) Phase Transformations III ...................................................................................................... Thurs. AM, Jefferson Ste (SCS) Physical Metallurgy of Electrical Steels I .................................................................................... Tues. AM, Consulate Ste (SCH) Physical Metallurgy of Electrical Steels II ................................................................................... Tues. PM, Consulate Ste (SCH) Physical Metallurgy of High Temperature Alloys ........................................................................... Wed. AM, Province Ste (SCH) Powder Metallurgy of Refractory Metals ........................................................................... Tues. AM, Commonwealth Rm (SCH) Processing I: Dissolution & Process Control ............................................................................ Mon. PM, Dominion Rm A (SCH)Processing II: Hydrometallurgy ............................................................................................ Wed. PM, Dominion Rm A (SCH) Processing Methods & Properties of Advanced Ceramic Materials 1.. ............................................ Mon. AM, Georgian Blrm B (SCH) Processing Methods & Properties of Advanced Ceramic Materials II ............................................. Mon. PM, Georgian Blrm B (SCH) Process Mineralogy-Methodology ......................................................................................... Mon. AM, Rhinelander North (H) Recovery Processes in the Secondary Metals Industry ................................................................ Tues. PM, Georgian BIrm B (SCH) Refractory and Energy Minerals ............................................................................................ Wed. AM, Rhinelander North (H) Shear Localization I ................................................................................................................ Tues. AM, Colonial Rm (SCS) Shear Localization II ............................................................................................................... Tues. PM, Colonial Rm (SCS) Solidification I ................................................................................................................... Wed. AM, Washington Ste (SCS) Solidification II ................... , .............................................................................................. Wed. PM, Washington Ste (SCS) Stephen R. Shatynski Memorial Symposium on Surfaces & Interfaces--I ............................................ Wed. AM, Consulate Ste (SCH) Stephen R. Shatynski Memorial Symposium on Surfaces & Interfaces--II ........................................... Wed. PM, Consulate Ste (SCH) Surface Analytical Techniques for Corrosion Studies I: Overview & Applications ................................. Tues. AM, Diplomat Rm (SCH) Surface Analytical Techniques for Corrosion Studies II: Aqueous Corrosion ....................................... Tues. PM, Diplomat Rm (SCH) Surface Analytical Techniques for Corrosion Studies III: Gaseous Corrosion ...................................... Wed. AM, Diplomat Rm (SCH) Surface Modifications .......................................................................................................... Thurs. AM, Diplomat Rm (SCH) Surfaces & Interfaces .......................................................................................................... Mon. PM, Princess Blrm B (SCH) Thermodynamics I: Activity & Free Energy Measurements .......................................................... Tues. AM, Dominion Rm B (SCH) Thermodynamics II: Solubilitly & Interfacial Energy .................................................................. Wed. PM, Dominion Rm B (SCH)

TMS-AIME Annual Meeting Program - 3

114th AIME ANNUAL MEETING TECHNICAL PROGRAM WITH ABSTRACTS The Metallurgical Society of AI ME MONDAY AM

test. The increase in hot ductn ity in the fusion zone corresponds with a microstructural refinement. Decanting techniques are employed to clarify the relationship between grain morphology and weld pool shape. Experimental measurements of grain orientation are related to welding velocity to show that yttrium additions affect both nucleation and growth rates during sol idification.

ADVANCES IN TITANIUM WELDING I: Physical Metallurgy and Alloy Weldability Sponsored by the TMS Titanium Committee Monday, February 25, 1985 8:30 a.m.

Jefferson Suite Sheraton City Squire

Session Chairmen: D. F. Hasson, Dept. of Mechanical Engineering, U.S. Naval Academy, Annapolis, MD 21402; F. H. Froes, Air Force Wright Aeronautical Laboratories, WPAFB, OH 45433

(8:30 a.m.) AN OVERVIEW OF PHASE TRANSFORMATIONS IN TITANIUM ALLOY WELDMENTS: W. A. Baeslack III, Department of Welding Engineering, The Ohio State University, Columbus, OH 43210; J. C. Williams, Carnegie Institute of Technology, Carnegie-Mellon University, Pittsburg, PA 15213 Weldment performance in titanium alloys is a strong function of the microstructures exhibited in the composite weld structure. These microstl'uctures are determi'ned by the Hquid-solid and/or sol id-state phase transformations that occur during the welding process. This paper will describe the current.understanding of phase transformations in titanium wel ds. The 1'nfl uence of wel d solidification phenomena on fusion zone beta grain morphology will be discussed, in addition to methods for controlHng this structure. Perhaps of more significance with regard to weld properties are the sol id-state beta decomposiUon reacUons. The influence of alloy chemistry and weld thermal conditions on these transformations and the resulting microstructures will be presented. Limitations in our current understanding of these phenomena will also be discussed.

(9:05 a.m.) WELDABILITY OF NOVEL DISPERSION-STRENGTHENED TITANIUM ALLOYS PRODUCED BY RAPID SOLIDIFICATION PROCESSING:* D. M. Bowden,

McDonnell Douglas Research Laboratories, St. Louis, MO 63166. Through the use of rapid solidification processing, fine uniform dispersoids which are effective in dispersion strengthening can be incorporated into a titanium alloy matrix. A study to evaluate the electron-beam weldability of several titanium alloys containing rare earth dispersoids has been conducted. Weld solidification structures have been studied to determine dispersoid size and distribution and extent of segregation of rare earth elements. Weld microstructures have been correlated with mechanical properties and fracture behavior, and the effects of post-weld heat treatment on structure and properties have been determined. *Research conduc ted under the McDonnell Douglas Indpendent Research and Development program.

(10: 15 a.m.) THE INFLUENCE OF YTTRIUM ADDITIONS ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF Ti-6Al-4V CASTINGS: W.J.Baxter and D.A. Bolstad, Martin Marietta Aerospace, New Orleans, LA 70189, M.A. Misra, Martin Marietta Aerospace, Denver, Colorado 80201 Titanium castings are used on the Space Shuttle External Tank (ET) for various ET/Sol id Rocket Booster and ET/Orbiter attachment fittings. It is desirable to increase the strength of existing Titanium castings and also improve the fracture toughness simultaneously. One of the methods to achieve this is by, grain refinement of the castings. In this preliminary investigation, a correlation of microstructure and mechanical properties was carried out on a series of Ti-6Al-4V cast and simulated weld repaired plates. The yttrium additions ranged from 0.04 to 0.08% and was accomplished in such a way as to minimize the oxidation of the yttrium metal. The microstructural modifications, tens il e properti es and fracture toughness as i nfl uenced by yttri urn additions are discussed on the basis of microscopic observations and

mechani ca 1

prc~~rty mea~:.!re~nts.

Research sponsored by NASA, George C. Marshall Space Fl i ght Center under Contract Number NAS8-30300.

(10:50 a.m.) THE EFFECT OF COMPOSITION AND WELD PROCESS ON THE SOLID-STATE PHASE TRANSFORMATIONS OF SOME TI-BASE WELDS: J. E, Gould, Inland Steel Company Researcli Laboratories, East Chicago, IN 46312; J. C. Williams, Carnegie Institute of Technology, Carnegie-Mellon University, Pittsburg, PA 15213 The effects of alloy type, amount of solute, and weld process on the sol id state phase transformations in some Ti-base welds has been examined. Binary Ti-Fe and Ti-Mo alloys over a wide range of compositions were welded with both GTA and electron beam welding processes. The microstructures of the resultant welds were analyzed with respect to the mode of beta decomposition, morpho'logy, and structure of the beta decomposition product. The amount of a·lloying addition had the greatest effect on the weld microstructures. Increasing the solute content refined the scale of the beta decompos i ti on product and eventually reta i ned the beta phase. This was observed for both types of addition, and both weld processes. Changing the alloy addition changed the kinetics of beta decomposition. Nucleation and growth decomposition in the Ti-Fe alloys was rapid, while in the Ti-Mo alloys was slow.

(11 :25 a.m.) DISTRIBUTION AND COMPOSiTION OF RARE EARTH OXIDES IN LASER MELTED TITANIUM AILOYS*: David B. Snow, United Technologies Research Center, (MS-24), Silver Lane, East Hartford, CT 06108

(9:40 a.m.) THE INFLUENCE OF YTTRIUM MICROADDITIONS ON TITANIUM WELD METAL CRACKING SUSCEPTIBILITY AND GRAIN MORPHOLOGY: M. C. Nordin, G. R. Edwards and D. L. 01 son, Center for Welding Research, Metallurgical Engineering Department, Colorado School of Mines, Go 1den, CO 80401 Yttrium microadditions (0.01-0.20 wt%) were made to titanium weld metal using the GTA wel ding process. Low concentrations of yttrium (below 0.2 wt%) reduce the fusion zone cracking susceptibility of Ti-6Al-2Nb-lTa-0.8Mo as determl'ned by the varestraint

Ti tanium alloys which contained 11 at% Al and 0.6 at% of a rare earth element were prepared from mechanically blended powder and rapidly solidified by LAYERGLAZESM processing. The rare earth oxide dispersions present in the as-processed microstructures were quantitatively characterized by analytical transmission electron microscopy. Alloy compositions after laser processing were obtained by electron microprobe EDS using standards, and by gas fusion analysis. The various oxide dispersions were compared to those observed in both conventionally cast and splat quenched alloys of similar compositions. *Research sponsored in part by the Office of Naval Research

4 - TMS-AIME Annual Meeting Program ALUMINUM REDUCTION TECHNOLOGY I: Developments Sponsored by the TMS Light Metals Committee Monday, February 25, 1985 8:30 a.m.

Royal Ballroom A Sheraton Centre

Session Chairmen: R. D. Zabreznik, Kaiser Aluminum & Chemical Corp., P.O. Box 1600, Chalmette, LA 70044; A. T. Tabereaux, Reynolds Metals Company, Reduction Laboratory, P.O. Box 1200, Sheffield, AL 35660

and alumina feed balance), and automatically controls anode-cathode distance, alumina feed, and input power. This system has saved 0.4 DCkWh/kg-AI and reduced unit energy usage to 12.9 DCkWh/kg-Al. Application of this system to the new MLI pots (150 kA-PB cells) has given good power consumption results of 12.6 DCkWh/kg-Al for a long period.

DEFORMATION I TMS-AIME General Abstract Session Monday, February 25, 1985 8:30 a.m.

(8:30 a.m.) NEW PRODUCTION MACHINES IN SODERBERG LINES: Andre Jauvin, Alcan Smelters and Chemicals Ltd. J Arvida Works, P. O. Box 1500, Jonquiere, Quebec G7S 412

Colonial Room Sheraton City Squire

Session Chairman: H. J. McQueen, Prof.. Mechanical Engineering, Concordia University, Montreal P.Q. H3G 1M8, Canada

Some years ago J a development program was undertaken to improve the working conditions in Soderberg lines. The results are: new crust breaker, pot trimmer, stud puller and stud planter,

(8:30 a.m.)

all of them equipped with air conditioning units and capable of

AND ALLOYS DETERMINED FROM STRESS CHANGE TESTS: D.O.Northwood* and I.O. Smith, Dept. of Mining & Metallurgical Engineering, University of Queensland, St.Lucia, Queensland 4067, Australia.

working in narrow passages.

(9:00 a.m.) ADAPTIVE CONTROL OF ALUMINA REDUCTION POTS WITH POINT FEEDERS Tom Moen, Johannes Aalbu and Tore Saksvikr¢nning, Ardal og Sunndal Verk a.s., N-5875 Ardalstangen, Norway. P Borg, Institutt for energiteknikk (IFE). Good alurninR feeding control is important to obtain optimum pot operation. Pots with point feeders may successfully be operated within narrow ranges of alumina concentration in the bath to reduce anode effect frequency and stabilize pot operation. This paper presents a method of controlling alumina addi tions to pots with point feeders by using an adaptive controller. The method and results from practical experiments are discussed.

(9:30 a.m.) MAGNETIC FIELD COMPENSATION AND CURRENT INCREASE IN POTLlNE SU III: !-. Solbu, Ardal og Sunndal Verk a.s., N-5875 Ardalstangen, Norway.

The magnetic field of 135 KA prebake pots was improved by rearranging the cathode busbars to permit increasing the amperage to 150 KA. The arrangements were mainly based on ASV's mathematical models for magnetic field calculations. The aim was to change the vertical field without disturbing the cathode current distribution. The improved bus bar system was tested on 11 cells over a period of 2 years at 150 KA. The bus of the whole pot line of 168 cells was rearranged one cell at a time while the cells were out for relining over a period of 4 years. The potline amperage was gradually increased to 150 KA in the last year of this period. The result hitherto is to decrease specific energy consumption by LO KWH/KG Al and increase the current efficiency by 1%. The amperage of the 11 test cells was subsequently increased to 160 KA, thus indicating a possible total increase in capacity of 20%.

(10:00 a.m.)

Break

(10:30 a.m.) IDTLINE cx)NVERSION 11) LITIDUM BATH: D. R. Shirley, Kaiser Aluninun & Chanical Corporation, Tacana, WA

Operation of a Soderberg reduction cell with Ii thium bath is a workable solution to the problEm of rising energy costs. HONever, conversion to lithiun is not instantaneous, nor problem-free.

The author addresses sane problEms encountered

during the first year of conversion and how the problans were resolved. He also discusses sane preparatory steps taken prior

to the addition of lithium.

WORK HARDENING RATES DURING THE STEADY STATE CREEP OF ALUMINIUM

Work hardening rates of aluminium and selected aluminium alloys during steady-state creep at 300°C were detennined from the instantaneous strains on sudden stress changes (increments and decrements). Alloys examined included AI-O.4%Li, AI-O.3%Li (in 3 different irradiated conditions), AI-2. 73 at%Mg and AI-4.20 at% Mg. Work hardening rates I h, varied from 0.1 to 1.5 times Youngs Nodulus, E. hiE decreased with increasing creep stress, o. At a given value of a, hiE was the lowest for polycrystalline alumininiurn and highest for the irradiated AI-O. 3%Li alloys. The values for hiE are compared with previously published values for f.c.c., b.c.c. and h.c.p. metals and alloys and found to be of the same order of magnitude. *Permanent address: Dept. of Engineering Materials, Univeristy of Windsor, Windsor, Ontario N9B 3P4, Canada.

(S:50 a.m.) Heasurernents of Anelastic Creep Strains in Al-S.5at%Mg*: M. J. Mills, J. C. Gibeling and \01. D. Nix, Department of Materi~ Science and Engineering, Stanford University, Stanford, CA 94305. Strain transient stress change experiments have been used to probe the substructure formed during steady state creep of an Al-5.5at%Mg solid solution in the alloy type (Class I) creep regime. In these experiments, stress reductions of constant magnitude (2.3 MPa) were performed from a range of initial stresses (4.6 to 20.5 MPa at 673K), and the total anelastic contraction was measured. Two distinct regimes of behavior have been. observed. For higher initial stresses (> 12 MPa ), the ratio b.E / b.E 1 remains constant for all initial stresses. This beha~~or iseconsistent with the predictions of a new dislocation model for creep in the alloy type regime. However, for lower ini tial stresses, which correspond to steady state conditions near the alloy/pure metal transition, I1E /I1E 1 increases sharply with decreasing initial stress. Thi~naddrfional anelasticity is suggested to result from the increasing presence of subgrains at lower stresses in the alloy type regime.

* Research supported by the National Science Foundation.

(9: 10 a.m.) COMPUTER SIMULATION OF HIGH TEMPERATURE CREEP' S. Patu. R. J. Arsenault and I. R. Kramer, Metallurgical Materials Laboratory. OiiTversTfy of Maryland, College Park, MD 20742 The phenomenon of high temperature creep has been investigated experi menta 11 y and theoret i ca 11 y for, many yea rs. Theoreti ca 11 y it has been shown that a stress exponent of three can be readily obtained, but the experimentally observed fifth power dependency is difficult to obtain. The role of "internal stress" hi) on the stress dependency of the creep rate is a subject of some controversy. A computer s i mu 1at i on invest i ga t i on was undertaken ba sed on the climb of edge dislocations. If the density of dislocation sources is related to the inverse of subgrain size and the screw component of the generated dislocation loops is proportional appl ied stress (0 ) then a fifth power stress dependence was obtained for stea~y state creep. If 1· is not a function of 0a then the stress exponent is independent of:;-:-:- However, if Ti is a function of 0a then the stress exponent is'a function of "i· *This research was supported by the National Science Foundation under Grant DMR-Sl-08422.

(11 :00 a.m.) ADVANCED COMPUTER CONTROL SYSTEM FOR POTLINE: T. Inoue. Y. Mino and O. Fuj ishima, Sakaide Plant, Mitsubishi Light Metal Industries Ltd., Bannosu-1, Sakaide, Japan

MLI has been developing energy-saving prebaked cell technology for 10 years. An advanced computer control system for the operation of highly insulated pots is now complete. This computer control system judges pot condition based on an analysis of pot data (pot resistance, anode effect information

(9:30 a.m.) BM~A~C~mQN

OF CLASS A TO CLASS M TRANSITION IN Pb-9Sn AND

~m~9~~eNtan~7~~g_~90g i nga Murty, N. C. State Uni vers ity,

Traosition frgm class A to class M types Of creep behavior. was well establlS ed ln many SOlld solution al oys ahd the cntenon for such a transition is a function mainly of the atom misfit ratio. stacking fault energy and solute atom concentration. The

TMS-AIME Annual Meeting Program - 5 condition for such a transltion is a function also of the relaive diffusitities governing the cl imb (class M) and glide ~lass A) cree~ mec~anisms. Consideratlon of toe appropriate lffusion coefficient and the contributions of the Suzuki and the Fisher interactions in addition to Cottrell-Jaswon iteracf~~ncme~~g~n f6n~r ~y t~~n~m~~~ t~t b~ s i~~g~~a~~rl nt~~£ 1 G~ sion of appropriate diffusivities in lieu of Darken diffusivity in glide-controlled creep' region (Cottrell-Jaswon interaction) and Herring diff{Sivity ip4cTimb-controlled region alon~ with gmel n cm~a~fttiB oth~~I~Olld i ~o~~m~t~l ~~' n~m~~t~gcl loy so 1ute concent rat i on, norma 1i zed stack i ng ¥{u lt energy, tem~£~~tnsa~~sgi~f~~~~m:s for climb and glide on transitional

l

ml

fg

g}

*Supported by NSF Grant DMR83l3l57

was attributed to anelastic strain storage delaying nonrecoverable creep during the on-load portion of the load cycle. Recent data for frequencies in the range 2.73 cycles/hr to 360 cycles/hr • however, indicate that there is no further decrease in minimum strain rate with an increase in cyclic frequency. A saturation of the effect is attributed to the time dependence of the anelastic strain storage. and specifically how this affects nonrecoverable creep for relatively short on-load periods. *This work is sponsored by the NSF under grant DMR80-11402 under the monitorship of Dr. Joseph Thomas.

(11:10 a.m.) INTERNAL FRICTION STUDY OF HYDROGEN IN NB-V ALLOYS*:

(9:50 a.m.) POWER LAW BREAK DO,}N DURING CREEP OF 1100 ALUMINUM AT HIGH TEMPERATURES* l. R. Kramer, R. J. Arsenault and C.R. Feng, tlet. Mats. Lab., Chem~-tngg. il-fda., Univ. of Maryland, College Park MD 20742 ' The dislocation densities, calculated from a Fourier analysis of the X-ray diffraction line profiles, were determined as a functim of the distance from the surface of 1100 Al specimens that crept at 673 and 773K at various stresSes. In the lower stress ranoe where the creep rate varied as 0 the dislocation density throughout the cross-section was uniform. However, in the higher stress range where the power law break down occurs the dislocation density was not uniform throughout the cross-section. A surface layer with a dislocation denslty much larger than that found in the interior was found. In the high stress region the dislocatim densities in the surface layer and in the interior increased very rapidly with stress. *This research was sponsored by the National Science Foundation under Grant DMR-8l-08422.

(10: 10 a.m.)

and

o.

C. V. Owen

Buck, Ames Laboratory, Iowa State University, Ames, IA

5001-1-.--

It is well known that the hydrogen SOlubility in Nb-V alloys is surprisingly large. This system is therefore ideally suited to study the effects of hydrogen on the internal friction spectrum without the interference of hydride precipitation. The present paper deals mainly with the effects of the Nb to V ratio on the hydrogen peak as determined at frequencies in the vicinity of 1 Hz (inverted pendulum). Preliminary results indicate that the activation energy of the peak depends on the Nb to V ratio. *This work was performed for the USDOE, Office of Basic Energy Sciences under Contract No. W-7405-Eng-82.

ELECTRONIC AND MAGNETIC MATERIALS TMS-AIME General Abstract Session Monday, February 25, 1985 8:30 a.m.

Georgian Ballroom A Sheraton Centre

Session Chairman: J. Bevk, AT&T Bell Labs., Murray Hill, NJ 07974

ON THE PRIMARY CREEP OF SUPERALLOYS*: W.L. Kimmerle, V.C. Nardone

and J .K. Tien, Center for Strategic Materials~ Henry Krumb School of. Mines, Columbia University, New York. N.Y. 10027 Although the various factors affecting the minimum creep rate and rupture I-ife of superalloys have been well documented, the subject of primary creep has received much less attention. This is somewhat surprising since for certain applications design criteria may have failure defined for creep strains as low as 0.1%. In this paper we first review and discuss the limited amount of literature on primary creep. In addition, the effect of stress and temperature on the time to reach a given percent strain is reported for some superalloys and ODS alloys. For example, the stress dependence of the time to reach various percent strains (up to 1.0%) for Udimet 700 with a grain size of 11.5 pm is shown to be similar to the negative inverse of the stress dependence of the minimum strain rate. The reported effect of stress and temperature on primary creep is discussed with respect to our current understanding of the primary creep and the effect of the resisting stress in the creep of particle strengthened alloys. *We thank both the Wyman-Gordon Company and the NSF tlClder grant DMR80-11402 for their sJpport of this project.

(10:30 a.m.) THE EFFECT OF MINIMUM STRESS ON THE CYCLIC CREEP PROPERTIES OF

MA6000*: William L. Kimmerle, Vincent C. Nardone and John K. Tien. Center for Strategic Materials, Henry Krumb School of Mines, Columbia University, New York. N. Y. 10027. Recent studies of nickel-base superalloys and oxide dispersion strengthened alloys at elevated temperatures have shown. that stress unloading during low cycle fatigue tests resulted in the recovery of a significant amount of strain. This presentation will report on the elevated temperature cyclic creep behavior of the oxide dispersion strengthened (ODS) nickel-base superalloy MA6000 as a function of minimum stressj the maximum stress, square wave form and frequency were the same for all tests. It is found that Inconel MA60DO exhibits increased steady state strain rates as the magnitude of the minimum stress was increased, however, in all cyclic tests the minimum strain rates remained less than the minimum strain rate of the static case. The cyclic creep behavior of MA6000 as a function of minimum applied load is shown to be explained by the suppression of anelastic recovery during the minimum load half cycle. *This work is sponsored by the NSF under grant DMR80-11402 under the monitorship of Dr. Joseph Thomas.

(10:50 a.m.) THE EFFECT OF HIGHER FREQUENCIES ON THE CYCLIC CREEP BEHAVIOR OF

AN ODS SUPERALLOY*: J. Stefani, V.C. Nardone and J.K. Tien. Center for Strategic Materials, Henry Krumb School of Mines. Columbia University, New York, N. Y. 10027. The behavior of the minimum strain rate as a function of frequency is determined for cyclic creep testing of Inconel MA6000 at 760 °C and cyclic stresses of 41-531 MPA. Previously, as much as an order of magnitude decrease in the minimum strain rate relative to static creep for the same maximum load was found to accompany a cyclic frequency increase in the range of .05 to 6 cycles/hr for MA6000. The mechanism for the frequency dependent cyclic creep deceleration

(8:30 a.m.) CAPILLARY INSTABILITIES IN POLY-CRYSTALLINE FILMS:

D. J. Sro!ovitz, Los Alamos National Laboratory, Los Alamos, NM, S. A. Safran, Exxon Research and Engineering, Co., Annandale, NJ The presence of grain boundaries in thin poly-crystalline films can lead to large perturbations to the film surface which can result in the break up of the film. These perturbations are in the form of grain boundary grooves. The kinetics of groove formation and the equilibrium groove depth are calculated for grain boundaries and grain boundary vertices as a function of grain size and groove angle. When the equilibrium groove depth is greater or equal to the film thickness, the film may develop holes or break up into discontinuous islands. Simple criteria for the forma~ion of grain boundary groove-substrate intersections, the stability of holes aad the stability of islands are established.

(8:50 a.m.) VAPOR GROWTH OF CdTe SINGLE CRYSTALS: A.S. Yue and C. Y. Yang, Department of Materials Science and Engineering, University of California, Los Angeles, California 90024. In this paper, we describe the preparation of CdTe single crystals by the vapour-phase-epitaxial growth technique, discuss the dislocation configureation of the etched (Ill) tellurium surface of the CdTe single crystal and propose a model accounted for the formation of such a dislocation configuration. An equation describing a one-dimensional shear stress acting on a (Ill) telluriUl!\ surface is derived. By neglecting the anisotropy of the CdTe crystal, the shear stress is calculated to be 1. 59 x 10 10 dynes/cm 2 • As a result of the crystallographic polarity, one surface of the CdTe seed crystal is the (Ill) tellurium surface and the other is the (111) cadmium surface. Now, the question is which surface is favorable for crystal growth? and why? To explain this difference in growth rate on these two surfaces, we assume that the formation of a tetrahedral bond in the CdTe crystal depends mainly' on the electron cloud of the Te atoms. If there are eight electrons surrounding a Te atom at any step-growing crystal, tetrahedral bond is easily formed on the (111) cadmium surface. Otherwise, it is difficult to form a tetrahedral bond.

(9: 10 a.m.)

CHARACTERISTICS OF NON-CRYSTALLINE Ni-P ELECTRODEPOSITS: I. De Iorio and V. Tagliaferri, Istituto di Tecnologie, Universita di Napoli, 80125 Napoli, Italy and L. Lanotte, Istituto di Fisica, Universita di Napoli, 80125 Napoli, Italy. This study deals with the production and then characterization of Ni-P electrodeposits obtained by different electrolitic solution. We have investigated the properties of the above mentioned deposits by several tests as mechanical, magnetic, structural and fractographic. Results of our analysis demonstrate the presence of non-crystall ine structure in accordance with 1 iterature. In particular, for an opportune P content, we succeed in producing a soft ferromagnetic amorphous material. The behavior of Ni-P alloys produced by this method are very interesting for many engineering applications.

6 - TMS-AIME Annual Meeting Program (9:30 a.m.) ANIS=P¥ IN THE ANNEALIt-K; SPErI'RUM OE" ELEl:CI'RCN IRRADIATED CU', A. C. Bailyt, W. E. King**, K. L. Merkle** and M. Meshiit, t Northwestern

University, Evanston, IL 60201 am **Argonne National Laboratory, Argonne, IL 60439. Stage I rEC'Overy SfECtra of ra::hation irdl..lCEd defects reflect their special distribution. 'Therefore, in near threshold irrcdiations, the dep?n:3ence of the recovery behavior on th:: crystallcgrar:hic direction of ircident electrons can irilicate to what extent the dynamic motion of rec:oil atoms in different directions results in different configurations of vacarcy-interstitial p3irs. I~situ electrical resistivity measurements were aWl iEd to electron transp3rent sp?Cimens in the ANL HVEM to determine damag-e prcdoction below 10 K am subsequent recovery. Stage I recovery sp2Ctra after near threshold irradiation establishErl striking differeoces between irraliation along the <100> an:J the <110> dirECtions. '!he <100> showed enhanced 1/1 an:J IB recoveries, while for (lID>, Ie was enhan::'E'd. '!he resistivlty remainirg after Stage I was nearly twice for thE:! <110) irrcdiation as canp:trro to <100>, irdicatirg that a larger fraction of more stable Fr"enkel [l3irs were formEd in th? direction. The results will be discusSEd in light of recent molECUlar dynamics calculations. 'Su['POrted by NSF (Grant #CMR81-14845) an:] the Dep3rlrra1t of Energy.

(9:50 a.m.) IlAGNt:rO-IoIECHANICAL EFFECTS ON CRYOGENIC Fe-9l1:Ni STEEL:'

G.O F'iOT. B fu1l2 and J. W. Morris. Jr., Dept. of Malerials Science and Mineral Engineering and MMRD. Lawrence Berkeley Laboratory, University of CalIfornia, Berkeley, CA 94720. Tensile tests with simultaneous exposure to high magnetic steady fields were performed for the first time on Fe-9%Xi sleel. The material had been heal treated to produce a fine dispersion of austenite particles. Two grades of 9!\i sleel were used for this experiments; 1) Overlempered material which conlained a relatively large volume fraclion of retained austenite. 2) Commercial heat treated material with standard volume fraction of relained auslenile. Magnetic effects ""ere observed for both materials at temperatures ranging from 4K to 296K. These effects scaled linearly with the applied field up Lo the maximum field tested (lB.1 Teslas). The magnetic effects, however, were of different magnitude and exhibited dissimilar strain dependence for each material; these differences are believed to be related to their respective retained austenite stability. The mechanistic sources of these magnetomechanical effects y,rill be discussed in connection with their microstruclural determinants. • Trus work was s".Jpported by the U.S. Depa:rtment of EnerBY under contract IDE-AC0376S:00098

(10: 10 a.m.) STATISTICAL THERMODYNAMICS OF ELECTRONS AND HOLES IN SEMICONN. A. Gokcen, U.S. Bureau of Mines, Albany, OR 97321

DUCTORS:

A rigorous statistical thermodynamic treatment is presented for the formation of electrons and holes in semiconductors, and for the accompanying standard changes in the Gibbs energy 6.Go, entropy 6.So, heat capacity 6.C and enthalpy 6.Ho. The treatment leads to the derivation of a meaningful equation representing variation of 6.Go with temperature, i.e. 6.Go - 6.GO(at 0 K) " E - Eg
,

ENERGY REDUCTION TECHNIQUES IN METAL ELECTROCHEMICAL PROCESSES I Sponsored by TMS-AIME Electrolytic Processes Committee Monday, February 25, 1985 8:30 a.m.

Versailles Ballroom Sheraton Centre

Session Chairmen: Renato G. Bautista, Department of Chemical and Metallurgical Engineering, University of Nevada Reno, Reno, NV 89557; Victor A. Ettel, Inco Ltd., Mississauga, Ont., Canada L5K lZ9

(8:30 a.m.) SAVING ENERGY IN THE ELECTROLYTIC RECOVERY OF METALS:·

G. M. Cook, Chemical Technology DiviSion, Argonne National Laboratory, Argonne, IL 60439. Many studies have been made of methods to reduce the quantity of energy used in the electrolytic recovery of metals. Thermal energy is required to maintain the desired operating teJDperature, to evaporate water, and to melt m.etal. The major use of electricity is the electrolytic process itself. The efficiency of converting fuel into usable thermal energy is on the order of 80%, whereas its conversion into electricity is only about 32%.

Thermal energy requirements are minimized by using adequate insulation and recouperatively designed equipment. The electrical energy requirement depends upon the process chemistry as well as the operating conditions and cell design. Therefore, reducing electrical energy use requires a complex solution. This paper reviews approaches for reducing energy use in the production of primary metals and identifies problems that have prevented the wider acceptance of these energy saving alternatives.

*Work

supported by US/DOE under contract No. W-31-109-ENG:...38.

(9:00a.m.) ELECTROLYTIC RECOVERY OF COPPER AND REGENERATION OF NITRIC ACID FROM A COPPER STRIP SOLUTION:· T. L. Steward and J. N.

Hartley, Pacific Northwest Laboratories, Richland, WA

99352

Fabrication of nuclear fuels involves the stripping of copper cladding with nitric acid. The waste acid which contains 3.0 to 4.5 M nitric acid and 150 to 180 gil copper is currently discharged, neutralized, and disposed of in solar evaporation ponds. Alternative waste disposal techniques including electrowinning are being investigated. Laboratory scale electrowinning tests have been conducted in an air sparged cell at 2 current densities from 0.027A/cm to 0.22A/cm 2 • The efficiency of copper recovery was improved by cooling the electrolyte or by adding sulfamic acid. Copper current efficiency ranged from 60-90% with up to 87% of the copper recovered. Results of the lab scale electro-winning tests are summarized. A brief comparison of alternative waste disposal and acid recycle techniques is presented. AResearch conducted for UNC Nuclear Industries under contract to U.S. Department of Energy.

(9:30 a.m.) ELECTROWINNING OF COPPER FROM HIGH- IRON LEACH SOLUTIONS: N. R. Bharucha, J. Cromwell, P. L. Claessens, Noranda Research Centre, 240 Hymus Boulevard, Pointe-Claire, Quebec H9R 1G5 Canada

A method of electrowinning of copper from leach solution containing high concentrations of iron, utilizing periodic reverse current, is described. Using this method, a reduction in power consumption of about 10 to 20% as compared to conventional direct current electrolysis is obtained depending on the initial copper and ferric ion concentration, in the pregnant solution. The results of a-comprehensive laboratory investigation, in which a full-height electrode cell was used to study the effect of such operating parameters as current density, PRC pulse duration and solution composition, are presented. Results obtained in a small pilot-plant operation are summarized.

(10:00 a.m.)

Break

(10:30 a.m.) OXIDATIVE ELECTROLYSIS OF AN ARSENICAL COPPER SULFIDE CONCENTRATE, K. P. V. Lei and T. G. carnahan, Reno Research Center, Bureau of Mines, U.S. Department of the Interior, Reno, NV An oxidative electrolysis procedure for leaching an arsenical copper sulfide concentrate was investigated by the Federal Bureau of Mines. The leaching was performed by electrolysis of a concentrate slurry chloride solution in a cell equipped with an ionselective bimembrane to separate the anodic and cathodic reaction. The bimembrane was composed of a cationic membrane superimposed on an anion membrane. Oxidation by chlorine at the anode converted the concentrate to soluble metal ions, arsenic acid, sulfate ion, and elemental sulfur. The effects of sodium chloride concentration, current density, temperature, and sulfate concentration on metal extractions and energy requirements for operating the bimembrane cell were determined. Metal extractions of more than 96 pct were obtaineci with the energy requirement ranging from 2.9 to 3.3 kW· h/lb of concentrate. A conceptual hydrometallurqical scheme to treat the arsenical sulfide concentrate is discussed.

(11 :00 a.m.) "SOLVENT EXTRACTION BICUPRIC ARSENATE PROCESS AT COPPER REFINERIES Armstrong, PTY. LTD., TOWNSVILLE, AUSTRALIA", P. G. Hall, R. and B. Middlin, of Copper Refineries Pty. Ltd., Townsville, Australia, and D. A. Winborne, of M.I.M. Holdings Lblited, Brisbane, Australia

,I.

The development design, construction and operation of the neH Solvent Extraction/BCA process plant at Copper Refineries Pty.Ltd. Townsville, is described. The process offers substantial savings in electrical power costs, improvements in plant hygiene, and a lowering of materials handling costs compared with conventional electrowinning technology. The sol vent extraction' process extracts arsenic from copper tankhouse electrolyte using a tributyl phosphate (TBP) - kerosene sol vent. The plant incorporates four extraction stages, two scrub stages, and three stripping

TMS·AIME Annual Meeting Program. 7 stages to produce an arsenic-bearing low-acid strip liquor. This strip liquor is mixed with CGpper sulphate, and neutralized with ammonia to form a copper (II) arsenic (V) crystalline product, bicupric arsenate (BeA). The product is used in the manufacture of chromated copper arsenate timber preservatives.

since July, 1981. Heavy metals in the mine drainage are precipitated with lime and removed from solution via electroflotation and filtration. The sludge produced is dewatered and stabilized with cement prior to disposal. The facility'has had an excellent operating history and habitat improvement in downstream drainages has been dramatic.

(11 :30 a.m.) STUDIES ON THE ELECTROWINNING OF NICKEL, COBALT AND COPPER FROM LEACH LIQUORS: S. C. Das, T. Subbaiah, P. Gopalakrishna, K. Srinivasa Rao, R. P. Das and P. K. Jena of Regional Research Laboratory, Bhubaneswar 13. India.

The leach liquor from various complex materials like nickel laterites, multi-metal sulphides and ocean nodules are presently treated through different separation processes. The present study aims to standardise the conditions for electroJinning of nickel, cobalt and copper from. such solutions. For the electrowinning of nickel, synthetic nickel sulphate solution, containing boric acid and sodium sulphate, was used. I'he optimum conditions for electrowinning of nickel in combined solvent extraction - electrowinning set-up were deterDined. These conditions were also tested using actual solutions obtained from reduction roasting and ammoniacal leaching Jf nickel laterites. Electrowinning of cobalt was studied, Jsing sulphate bath in the absence of additives as well as in the presence of additives like H3B03' and NaF. It was observ!!d that the additives improve current efficiency and favour bright deposits.

ENVIRONMENTAL CONTROL Sponsored by the Joint TMS/SME Environmental Control Committee Monday, February 25, 1985 8:30 a.m.

Commonwealth Suite Sheraton Centre

Session Chairman: R. A. Malone, Kennecott, Salt Lake City, Utah 84147

(8:30 a.m.) OVERVIEW OF THE U.S.E.P.A. MINE WASTE MANAGEMENT STUDY, Richard L. Harlan, Dames & Moore, Golden, Colorado

The U. S. Environmental Protection Agency is mandated by Congress under the Resource Conservation and Recovery Act (RCRA) of 1976 and the Solid Waste Disposal Act Amendment of 1980 to develop recommendations on regulation of waste management practices in the mIning industry. Preliminary to the development of its recommendations, EPA initiated, among other activities, a study of past and current mine waste management practices in the uranium, phosphate and metal (copper, lead, zinc, gold, silver, iron, tungsten, and molybdenum) sectors. This study included (1) a p~esurvey of waste management practices at 65 active and abandoned mines within the continental United States, (2) surfacewater a~ ground-water monitoring at eight mine sites, and (3) an office evaluation of the effectiveness of past and current mine waste management practices. The American Mining Congress commissioned an independent review of the EPA study. This paper presents the results of this overview.

:9:00 a.m.) COOPERATIVE GROUND WATER STUDY AT KENNECOTT'S BINGHAM CANYON MINE: S. D. Taylor, T. D. Vandell, Kennecott, Salt Lake City, Utah; Terry Holzworth, Salt Lake Co. --Flood Control & Water QUi:llity

In June of 1983, a comprehensive 5.25 year-$1.3 million groundwater quality study was initiated by Kennecott at its Bingham Canyon Mine, Salt Lake City, Utah. The purpose of this study is to determine historic, existing and, future ground-water quality impacts from other pre-Kennecott mining company operations in the Bingham Canyon Mining District, ongoing since 1865, and Kennecott's mining operations, ongoing since 1936, which include open pit mining, acid leaching of overburden dUfllPs and mine water discharge to holding and evaporation ponds. To assure that the hydrogeologic study progresses at a timely rate and that field and laboratory work are technically valid and acceptable to the regulatory agencies, a technical group and advisory group oJ state, county, federal EPA and Kennecott scientists and administrative staff were formed. These groups meet at least 1/2 months to review and discuss the new hydrogeologic data and to consider revisions to the original study plan.

(9:30 a.m.) CLIMAX MOLYBDENUM COMPANY'S MOUNT EMMONS WATER TREATMENT FACILITY: G. G. Van Riper, C. Harnish, A. Ortiz and J. C. Gilliland, Climax Molybdenum Co., a Division of AMAX Inc., Golden, CO. An operating treatment facility at Climax Molybdenum Company's Mount Emmons Project located near Crested Butte, Colorado, has been operating effectively in removing heavy metals from an inactive base metal mine

(10:00 a.m.) CYANIDE FROM A REGULATORY PERSPECTIVE-A COMPLEX ISSUE: Robert E. Walline, U.S. Environmental Protection Agency, Region VIII, 1860 Lincoln Street, Suite 280, Denver, Colorado 80295 Issues surrounding cyanide in mining industry wastes are discussed. The nature of cyanide chemistry in mining effluents is presented. That leadS to a discussion of how that chemistry impacts analytical methods, treatment technologies, and environmental impacts. The impl ications to operators disposing of cyanide wastes is covered. The emphaSis is on precious metal operations including small operators. Future treads in regulatory approachs are outl ined in the context of NPDES, RCRA,and Environmental Assessments. Recommendations are made on areas to consider in an evaluation of the impacts of disposal of mining wastes containing cyanide.

(10:30 a.m.) LEGAL AND KEGULATORY TRENDS IN ENVIRONMENTAL CONTROL REQUIREMENTS, Alfred V. J. Prather, Prather Seeger Doolittle & Farmer, 1101 Sixteenth Street, N.W., Washington. D.C.

Legal and regulatory trends in environmental control requirements were reviewed for air. water and solid wastes, with emphasis on acid rain, visibility, ambient air standards, groundwater and hazardous waste. Environmentalist pressures on both Congress and the Environmental Protection Agency are stronger than ever and can be expected to produce statutory and regulatory changes. Statutory changes are likely on acid rain and hazardous waste. Regulatory actions on visibility, ambient air standards and groundwater are to be expected. Recent emphasis on risk assessment will spread to more areas of regulation. Enforcement activity by EPA, state and private litigants is increasing. These trends will increase the need for engineers and lawyers to work together.

ENVIRONMENTAL CONTROL I Sponsored by the TMS Light Metals Committee Monday, February 25, 1985 8:30 a.m.

Imperial Ballroom A Sheraton Centre

Session Chairmen: V. L. Bullough, Reynolds Metals Company, Carbon Products Division, Baton Rouge, LA 70809; E. R. Cutshall, Reynolds Metals Company, P.O. Box 1200, Shefield, AL 35660

(8:30 a.m.) ALUMINIUM PECHINEY-OCCUPATIONAL MEDICINE - JOB STUDIES - DR JP. COULON ALUMINIUM PECHINEY PA!HS, G. nUP1\AT L~" ST JEAIl DE MAiiiUENNE • A new method of studying the hardness of the working conditions in the aluminum industry has been developed by Pechiney. Basically, this method allow to find out the more tiring tasks of a job, their causes and the means to eliminate them. This method is presented by describing a real case. Furthermore, the resul ts of the studies carried out to jobs in old potlines and in potlines using the last Pechiney technology show the tremendous improvements of the work conditions. Particular emphasis is put on the interest of : . measuring the heart rate to evaluate the hardness of a task, . using this method by the plant physician to improve his knowledge of the plant jobs and his relationship with the workers, . processing the results by a team including physicians, engineers and workers. It is planned to use this method to study all the jobs in the aluminum industry. These studies may provide additional elements for orienting certain technological research project.

(9:00 a.m.) TECHNO-ECONOMICAL COMPARISON OF VARIOUS SULFUR REMOVAL PROCESSES: CRUDE OIL - PETROLEUM COKE AND ALUMINA REDUCTION PROCESS U. Mannweiler, R. E. Frankenfeldt, Swiss Aluminium Ltd., Research + Development, CH-B212 Neuhausen a/Rhf., Swiss Aluminium Ltd. Primary Aluminium, CH-B03~ Zurich/Switzerland Declining crude quality, combined with changing refined product demand will affect supply and quality of the petroleum coke market. The sulfur content in the calcined coke and finally in the baked anodes for the aluminum industry is expected to increase, which will result in higher S02 emissions from smelters.

8 - TMS-AIME Annual Meeting Program Desulfurizing techniques for crude oil and green coke as well as methods for desulfurizing waste gases from smelters will be discussed. An economical comparison of the various techniques and the influence on petroleum coke price will be given.

radioactivity obtained, and indicating equipment developed. Study on different amperage was carried out. It was found that use of developed method allows determination of efficiency of the fume exhaust systems and individual pots in different periods of operation with high accuracy. Calculations of determination error were performed.

(9:30 a.m.)

FORMATION AND DISTRIBUTION OF CYANIDE IN THE LINING OF ALUMINUM REDUCTION CELLS: R. W. Peterson, L. C. Blayden and E. S. Martin, A1umi num Company of AJilerl ca, Alcoa Center, PA 15069 The cyanide content of spent potlining spans four orders of magnitude in a single smelting cell. Typically over 90% of the cyanide is found in the ends and sides of the cells; little is found in the cathode blocks and bottom insulation. Nearly 80% of the cyani de can be extracted by a water 1each and most of that is amenab 1e to ch 1ori nat i on. Cyani de is found in non-carbonaceous materials indicating it forms elsewhere and migrates to relatively cool regions of the cells. Conditions within a smelting cell favor formation of NaCN. Bench scale experiments show nitrogen( 1 reacts readily with sodium impregnated carbonaceous materi~~S at 800 0 C to form substantial quantities of NaCN in short exposure periods. Graphite and semi -graphi te impregnated wi th Na yi e 1d ssvera 1 fold more NaCN in short term tests under nitrogen! ) at 800 C than do anthracite carbon block specimens. The liR~ly source of the nitrogen is air inleakage rather than nitrogen in the lining materials.

(10:00 a.m.) A STUDY OF CYANIDE DISTRIBUTION AND FORHATION IN ALUMINIUM REDUCTION CELL LININGS: B. K. ~, Technical Services Department, Camaleo Aluminium (Bell Bay) Limited, George Town, Tdsmania, Australia.

From autopsies of failed cells, the cyanide distribution profiles within the linings were extensively mapped, as part of an invest-

igation into factors likely to influence cyanide formation. A parallel laboratory study was conducted to determine the susceptibility of different forms of carbon to cyanide generation, the carbon ranging from plant derived sidewall-mix through commercial prebaked cathode material to high purity graphite. In the laboratory study, sodium cyanide was synthesized by impregnating the carbon specimens with metallic sodium followed by chemical reaction with pure nitrogen. Whilst cyanide formation was found to readily occur in the temperature range of SOO-60GOC in all carbons tested, the less ordered sidewall mix was sign'ificant1y more vulnerable. The reaction was accelerated by the presence of iron impurities, and the amount of cyanide generated in a given reaction time can vary by a factor of three. Autopsy examination of flotlinings reved1ed U-,dt ffiujor amot::-:.!..~ of cyanide were generally concentrated in the carbon sidewall and in regions near the collector bars. These observations would not be inconsistent with laboratory measurements. The cyanide profiles suggest that air ingress through the collector bar seals into and sodium saturation of the carbon also influence the favoured region for cyanide formation.

(10:30 a.m.) PHYSCIO-CHEMICAL PROPERTIES OF ALUMINA USED FOR REMOVING FLUORIDES IN THE DRY CLEANING SYSTEMS: V. S. Burkat! V. S. Dudorova, V. S. Smola, T. S. Chagina, G. Zakharova, VAMI Institute, Stredmye Prospect 86, 199026, Leningrad, USSR. Physical characteristics, structure, and adsorption ability of aluminas were studied with the view of their possible use for adsorption of HF. size distribution and phase composition of aluminas specific area and porous structure as well as distribution of these factors by fractions were studied. Adsorption isotherms of hydrogen fluoride were studied in the range of partial pressures of HF corresponding to those of industrial conditions reacted alumina was studied by X-ray thermographic, and NMR-spectrosopic methods. Th'e results of the study were used as the basis for establishing specifications for aluminas employed in USSR-developed dry scrubbing systems at aluminium smelters.

(11 :00 a.m.) USE OF THE RADIOACTIVE INDICATORS METHOD FOR EVALUATING AN EFFICIENCY OF REMOVING THE CONTAMINATES IN THE ELECTROLYTIC PRODUCTION OF ALUMINIUM: 1. N. Popchenkov, L. E. Safarova, K. V. Yablonsky, VAMI Institute, Stredmye Prospect 86, 199026, Leningrad, USSR. The collecting efficiency of the pot enclosure is one of the most important performance parameters. Known methods used for its determination are labor intensive, complicated, and provide but estimates at best. USSR has developed the method with use of tracer elements based on Krypton-8S. The method of tracer introduction was studied, justification of the level of required

G. R. FITTERER SYMPOSIUM ON NITROGEN IN METALS AND ALLOYS I Sponsored by the ASM-MSD Thermodynamic Activity Committee Monday, February 25, 1985 8:30 a.m.

Consulate Suite Sheraton Centre

Session Chairmen: R. Schmid, University of Clausthal, Clausthal, W. Germany; and Z. Morita, Department of Metallurgical Engineering, Fac· ulty of Engineering, Osaka University, Osaka, Japan

(8:30 a.m.) INTRo:JUCTORY REMARKS: N. A. Gokcen, Bureau of Mines, U.S. Department of the Interior, Albany, OR 97321

(8:50 a.m.) EFFECTS OF ALLOYING ELEMENTS ON THE SOLUBILITY AND ACTIVITY OF NITROGEN IN IRON-, COBALT-, AND NICKEL-BASE ALLOYS: E. Schiirmann, University of Clausthal, Clausthal, West-Germany, M. Sittard, Thyssen Steel Corporation, Duisburg, West Germany, and R. Volker, University of Clausthal, Clausthal, West-Germany Isothermal nitrogen solubility and activity coefficient in ternary and multicomponent iron-, cobalt-, and nickel-rich alloys in the temperature range of 1773 to 1973 K are expressed as functions of composition and temperature by the so-called equivalent model. The partial molar enthalpy 6HN and the excess entropy as:. are calculated from the equation for the activity coefficient, using only one specific factor. Effects of the alloying elements in iron-, cobalt-, and nickel-rich systems are discussed. Co"mparison of the liquid and solid mixing behavior of the binary metallic systems with the nitrogen solubility, influenced by addition of alloying elements, is accomplished. Possibility and accuracy of prediction of the influence of alloying elements on nitrogen solubility are evaluated. Application of the equivalent modE!:! to determination of thermodynamic properties of the dissolved nitrogen and the components of alloys is discussed in detail.

(9: 15 a.m.)

ACTIVITY COEFFICIENT OF NITROGEN IN BINARY LIQUID ALLOYS: J. C. Lin, R. Schmid and Y. A. Chang, Department of Metallurgical and Mi nera 1 Engl neeri ng, 1509 Universi ty Avenue, Madi son, WI 53706 The activity coefficient data of nitrogen if several binary liquid alloys were evaluated by Lin and Chang in terms of \:he Wagner model. 2 We have recently relaxed one assumption in this model taking into co~sideration the non-ideal behavior of the solvent metal atoms. The available data for nitrogen in several binary alloys are evaluated in terms of :':!'tis equa~ion and compared with the evaluation of Lin and Chang using 'the original Wagner equation. The basic limitation of the solvation shell model will be discussed.

1. 2. 3.

R. C. R. to

Y. Lin and Y. A. Chang: Met. Trans., 1977, 8B, 293-300. Wagner: Acta Met., 1973, 21, 1297-1303. Schmid, J. C. Lin and Y. A:-Chang: to be submitted Z. Metallkde.

(9:40 a.m.) NITROGEN SOLUBILITY IN COMPLEX LIQUID Fe-Cr-Ni ALLOYS: D. S. Shahapurkar, Cabot-Beryl co Corporation, Reading, PA 15601, and M. Small, Pennsylvania State University, University Park, PA 16B02 Measurements of nitrogen solubility were made in a series of liquid iron-chromium-nickel alloys of composition close to Incoloy-BOO (21%Cr, 33%Ni, 46%Fe) in the range of 1450-1600" C, and up to 1 atmosphere of nitrogen gas pressure. Sieverts' Law was obeyed by all of the alloys. Slight compositional changes were observed in the melts of all the alloys studied, mainly due to chromium loss by volatilization. These melt adjustments necessitated nitrogen solubility measurements in a series of alloys immediately surrounding composition of Incoloy-BOO. The results of these measurements are presented as a regressed polynomial equation for the logarithm of nitrogen solubility as a function of temperature, and reported percentages of chromium and nickel in the alloys. The standard Gibbs energy of nitrogen solution in Incoloy-800 is given as llG" = -57,280 - 47.68 T Joules/g atom N. For a neighboriag alloy (25%Cr, 33%Ni, 42%Fe) IIG" =-60,630 - 47.38 T Joules/g. atom N.

TMS-AIME Annual Meeting Program - 9 (10:05 a.m.)

Break

(10:20 a.m.) SOLUBILITY OF NITROGEN IN LIQUID CHROMIUM AND CHROMIUM-IRON ALLOYS: F. Ishii, Y. Iguchi, and S. Ban-Ya, Department of Metallurgy, Tohoku University, Senda!, Japan, 980 The solubility of nitrogen in liquid chromium and chromium-iron alloys has been measured by a sampling method from 1550 to 1780 0 C at 0.04 to 1.0 atm of nitrogen. Nitrogen in liquid chromium and chromium.-iron alloys up to 50% Fe does not obey Henry I slaw. The Gibbs energy of solution and the activity of nitrogen in liquid chromium and chromium-iron alloys were calculated from the experimental results by applying the interstitial solution model. The apparent equilibrium constant log K' (z) exhibits a linear relation with the atomic ratio of nitrogen YN defined as YN = XNI (1 - XN), where XN is the atom fraction. The activity coefficients of nitrogen, and the values of log K(z) are given by the following equations:

'P:

N

YN< 0.21, 1700 - 1780° C log K(z) = 55l5/T - 3.19 3 ; K(z) = ap;;; = ~.ZN/~' where ZN is log ~N(Cr) - (4235/T - 1. 513 )·Y N;

the lattice ratio of nitrogen in liquid metal, ZN

=

~/(1-2XN)·

the oxygen pressure in a copper flash smelting furnace at TOYo Smelter is discussed. Vertical variation of oxygen pressure in the reaction" shaft is affected significantly by the performance of the concentrate-burner. The oxygen pressurE'. calculated by the equilibrium model is much lower than tha t measured in the ac tual furnace. This discrepancy is attributed to the excess magnetite which is contained in the furnace charge and formed in the upper zone of the reac t ion shaf t.

(8:55 a.m.) THE ELKEM MODULAR FREEZE-LINING: J .A.Aune ,Elkem als Engineering, Middelthunsgate 27,Majorstua 03034, Oslow 3 Norway Laboratory and pilot-plant developnent of a force-cooled and :fully controlled freeze-lining is described.The design is based on two cooling principles; convective and evaporative, both allowing online monitoring of process heat-strains and freeze-liningcondition. Convective circuitS/back-up systems were developed based on synthetic heat-transfer media for several reasons: greatly reduced vapour-explosion hazards, increased system reliability elimim.ting scaling, deposits and corrosion, energy-recovery through hot-media operation, etc. Evaporative circuits e.g. special thermal syphons were developed to eliminate coolant circulation below metal level. Further advantages of applying evaporative cooling in the slag/metal interface area are thermal syphon I s reliability due to the lack of moving parts and back-up systems and their ability to withstand extreme heat-strains.

ts f~~tli=e~lt~ s;~t~ie~~~~a~r~igg ~~a~~~rm~~~~~iu~~ier~t~~~t~~,

(10:45 a.m.) EQUILIBRIA OF NITRIDE FORMING REACTIONS IN LIQUID IRON ALLOYS: Z. Morita, and T. Tanaka, Department of Metallurgical Engineering, Faculty of Engineering, Osaka University, 2-1, Yamada-oka, Suita, Osaka 565, Japan There are few reliable data on the equilibria of nitride forming reactions in liquid iron alloys, while so far, the solubilities of nitrogen in liquid iron and steel have been studied by many investigators. Published thermodynamic data on the nitride forming reactions in liquid iron alloys containing Al, B, Nb, V, Ta, Ti, and Zr are critically reviewed. New data on vanadium nitride dissolution-formation reaction in liquid Fe-V alloys were obtained by the sampling method of the authors. The reaction investigated and the corresponding change in the standard Gibbs energy, ~Go, are as follows: VN(s) = V + N, for which AGO - 167 - 0.0837 T ± 1.5 (kJ/mol) (1873 - 1973 i). A series of possible nitride forming reactions in liquid iron alloys are discussed in terms of the standard Gibbs energy and enthalpy of formation of nitrides, atomic numbers of nitride forming elements, and interaction parameters.

expansion counter-measures/control and safety back-up systems. The consequences with respect to optimal reactor dimensioning are finally briefly discussed.

(9:20 a.m.)

*

EXPERIMENTAL STUDY OF COPPER DEOXIDATION BY NON-SOLUBLE flUXES: E.S. Geskin, New Jersey Institute of Technology, Newark, NJ, and E. Ling, Revere Copper Products, Inc., Rome, NY

The feasibility ·of redUCing oxygen content in the molten copper down to 1-2 ppm without the use of atmospheric or vacuum furnace has been studied. Various deoxidation techniques were tested, and the most effective technique is the use of charcoal packed bed. The oxygen content in molten copper can be reduced to 1-2 ppm from a few thousand ppm within 1-2 minutes using this technique. It is suggested that oxygen-free copper could be produced by charcoal filtration technique. Other techniques which were found to achieve the objective but with a much slower rate are: insertion of graphite rods, use of melt cover of graphite powder, CaC 2 particles, or CaF 2-NaF power mixture.

(11 :15 a.m.) A REVIEW OF THE VANADIUM-NITROGEN SYSTEM: By O. N. Carlson, J. F. Smith, Ames Laboratory, Iowa State University, Ames, lA, and R. H. Nafziger, Albany Research Center. Bureau of Mines, U.S. Dept. of the Interior, Albany, OR The paper consists of a critical evaluation of available data on the vanadium-nitrogen system. Two compounds, VN and V2N, have been definitely established, and their reported crystal structures, ranges of homogeneity, and melting or dissociation temperatures are examined in detail. Several other vanadium-rich phases, tentatively identified as V16N, V13N, V16N2, V9N2' and VxN. have been reported, and an attempt is made to differentiate the thermodynamically stable phases from the metastable ones. The dissociation temperatures and pressures and other thermodynamic properties of the various phases in the system are summarized and evaluated. The effects of temperature and pressure on the solubility of nitrogen in vanadium are reviewed. A partial phase diagr811 is proposed based on available crystallographiC, thermodynamic, and meta110graphic evidence.

(11:40 a.m.) PANEL !lISCUSSION BY AUTHORS

*This work was sponsored by TMS-AlME Pyromatallurgy Committee

(9:45 a.m.) Bunker fuel oil poling in anode furnaces at the Kosaka Smelter: J. Minoura, K. Satoh and Y. Mitsune, Kosaka Smelter, Dowa Mining Co., Ltd., Kosaka. Kazunogun, Akita, Japan 017-02. An ammonia gas poling process was adopted for newly installed anode furnaces at the Kosaka Smelter in 1967 when the smelter was rationalized with advanced technologies, because the price of ammonia was expected to fall by steady growth of fertilizer industry at that time in Japan though the practice of ammonia gas poling had some problems in handling equipment, consuming a fair volume of steam to gasify the liquid ammonia, and evaporating copper during poling. The price of ammonia, however, drastically rose four times after oil crises in 1973 and 1978. In 1979. ammonia gas was switched to bunker fuel oil to reduce operational problems as well as saving poling cost. In this paper, a process development of bunker fuel oil poling, performance, and comparison of poling costs are described.

GENERAL PYROMETALLURGY I Sponsored by the TMS Pyrometallurgy Committee Monday, February 25, 1985 8:30 a.m.

Province Room Sberaton Centre

Session Chairmen: H. Asao, Onahama Smelting and Refining Co. Ltd., 1-1 Nagisa Onahama, Iowki City, Fukushima, Japan; B. C. Kellogg, Harbison-Walker Refractories, Pittsburgh, PA 15222

(10:10 a.m.)

ENERGY CONSERVATION AT INCO'S COPPER CLIFF SMELTER: T. N. Antonioni, J. A. Blanco, C. A. Landolt, W. J. Middleton, Inco Limited Copper Cliff Smelter, Copper Cliff, Ontario POM lNO, Canada lnco's Copper C11ff Smelter processes nickel and copper concentrates at rates of about 850,000 and 450,000 tons/year. respectively. The main products from the plant are a Ni-Cu white metal and blister copper; current annual rates are about 230 million lbs of Ni and about 260 million lbs of copper.

(8:30 a.m.) THERMODYNAMIC CONSIDERATION FOR OXYGEN PRESSURE IN A COPPER FLASH SHELTING FURNACE AT TOYO SMELTER: N. Kemori, Y. Shibata and K. Fukushima Toyo Smelter, Besshi Division, Sumitomo Metal Mining Co., Ltd. Funaya, Saijo, Ehime, Jap::ln Based on the EMF measurements of the galvanic cell (Fe, FeOI Zr02 + MgOI Q in slag or matte) and the equilibrium calculations,

Processing facilities at the Smelter consist of multihearth roasters, reverberatory furnaces. an oxygen fl ash smelt i ng furnace and Pei rce Smith converters. The purchased energy required to operate the Smelter accounts for about 40% of the purchased energy "input to Inco's Ontario Division. "including mines. mi 11 s, smelter and refi neri es. In recent years, poor market conditions, coupled with 50 2 emission restrictions have led to a decrease in the tonnage and an increase in the grade of the Ni concentrates, while fuel costs have risen at an annual rate of '\,20%. The Copper Cliff Smelter initiated a major energy conservation program in the late 70's. As a result. specifiC purchased energy requirements (BTU/ton rli) have been reduced by '\,30~ from 1980 to date. in spite of a decrease of 10 in the specific thermo-chemical heat input.

10 - TMS-AIME Annual Meeting Program This paper details the actions that have led to these results. - Development of heat balances for key process units and flues. and the implementation of periodic energy audits of the system. Increased use of oxygen in reverberatory furnaces. Improved productivity of processing equipment. - Oecreased air inleakage to the flue system, attained by rationalization and improved draft control.

(9: 10 a.m.) ANAL YSIS OF DISLOCATION PILE-UPS NEAR HIGH ANGLE BOUNDARIES IN 304 STAINLESS STEEL: Z. S. Shen, H. S. Betrabet, R. H. Wagoner, and W. A. T. Clark, Dept. of Metallurgical Engineering, The Ohio State University, 116 West 19th Avenue, Columbus, Ohio 43210

At Naoshima Smelter, lead sintering off-gas has bee~ utili zed as the burne . . . air for the copper reverberatory furnace by enriching with tonnage oxygen. The advantages of the increased plant capacity and reduced cost by the decreased gas volume and elimination of the decoloring of the black acid at the acid plant are dealt, along wi th the combustion state in the reverberatory furnace.

Deformed samples of polycrystalline 304 austenitic stainless steel have been studied in a transmission electron microscope (TEM) at 200 kV. It was found that dislocation pile-ups at grain boundaries can result in the dislocations propagating across the boundary into the adjacent grain or along the boundary to form part of the grain boundary dislocation network. The Burgers vectors of the crystal lattice dislocations and those of the grain boundary dislocations were accurately determined.. The crystallography of the pile-ups, boundaries and grains were completely characterized in the TEM and subsequently used in stress and force field calculations. These computations are based on anisotropic elasticity and include a consistent elastic boundary effect. This combination of experiment and calculation allowed qualitative determination of mechanisms of slip propagation across grain boundaries and a quantitative estimate of the local stresses involved.

(11:00 a.m.)

(9;30 a.m.)

The Secondary Copper Smelter at Brixlegg/Austria: H. Woerz and J. Wallner, Helmelt Woerz, Burlegg GMBH, Postfach 9A-6230 Burlegg, Austria

STRUCTURE OF GRAIN BOUNDARIES IN Ni + Al AND Ni + Al CONTAINING B: R. J. Kerans, II. A. T. Clark an~-~. P. Hirt~~"oepartment of Metallurgical Engineering, The Ohio State University, Columbus, OH 43210

(10:35 a.m.) UTILIZATION OF LEAD SINTERING OFF-GAS AS BURNER AIR FOR COPPER REVER3ERATORY FURNACE: H. Saito, E. Oshima, S. Kanlia and M. Hirano, Naoshima Smelter, Mitsubishi Metal Corporation, Naoshima-cho, Kagawa-gun, Kagawa-ken, Japan

ABSTRACT NOT AVAILABLE

(11 :25 a.m.)

TUYERE INTERACTION IN METALLURGICAL CONVERTERS: M. Nilmani and N. B. Gray, University of Melbourne, Chem. Eng. Dept., Parkville Victoria 3052, Melbourne, Australia. In many metallurgical reactors (e.g. Cu converter, Az and Sn fumer) gases are injected into melts - through a series of closely spaced tuyeres. For a good gas/liquid dispersion it will be desirable that the neighbouring tuyeres do not interact and act independently to enhance the dispersion. The present experimenta 1 study exami nes the gas i nteracti on from nei ghbouri ng tuyeres us i ng tuyere pressure responses, both ina room temperature rig and in industrial copper converters.

GRAIN BOUNDARIES TMS-AIME General Abstract Session Monday, February 25, 1985 8:30 a.m.

Imperial Ballroom B Sheraton Centre

Session Chairman: D. A. Smith, Research Staff Member, IBM Corporation, P.O. Box 218, Yorktown Heights, NY 10598

Transmission electron microscopy has been utilized to study the structure of high-angle grain boundaries in the LIZ compound Nl 1 + Al and Nt, ... Al containing B. Relative misorientations were defe~ined by KI~uchi band analysis. The grain boundary dislocation substructures are compared to those predicted by CSL-DSCL theory. Implications regarding slip transmittal across grain boundaries and polycrystal deformation are, discussed.

(9:50 a.m.) THE RELATIONSHIP BETWEEN y' and M23 C6 DISTRIBUTIONS AND THE MECHANICAL PROPERTIES OF THE NICKEL BASE SUPERALLOY X-750: J.D. Rossi, K. Zeik and P.R. Howell, Department of Materials Science and Engineering, Penn State Univ., University Park, PA

Previous studies in the authors laboratory have shown that the "Rising Load" behaviour of X-7S0 is highly dependent on the ageing temperature employed prior to testing. Specifically, a trough in the Rising Load times was found at intermediate ageing temperatures. In the present investigation, transmission electron microscopy has been employed both to document the distribution of the y I and M23 C6 precipitates as a function of temperature for a constant ageing time of 20 hours, and to measure the width of chromium depleted zones developed in the vicinity of grain boundries. Finally, the precipitate distributions, and the extent of the chromium depleted zones have been correlated with the mechanical response of the material.

(8:30 a.m.) MIGRATION OF LlQUIFIED GRAIN BOUNDARIES: P. W. Voorhees, R. J. Schaefer, and C. A. Handwerker, Metallurgy Division, National Bureau of Standards, Gaithersburg, MD 20899

This research was supported by Westmoreland Mechanical Testing and Research Inc.

Experiments whi ch have been sonducted in 2024 A1, W-Ni, and succinonitrile (scn)-O.l m/o acetone all show clear evidence of rapid migration of liquified grain boundaries. Autogeneous electron beam welds of 2024 Al resulted in boundary migration velocities in 6 the partially melted zone -'1 ~/sec as a result of the large '""'10 K/m temperature gradients. In contrast, in W-Ni, and scn-O.l m/o acetone, the boundary migration appears to be capillarity driven. In all of these experiments, the freezing solid-liquid interface of the migrating film became unstable, developed a cellular morphology and left behind droplets or sheets of the liquid phase in the solid matrix. The resulting material thus contained regions highly concentrated in solute. The experimental results, mechanisms for boundary migration and droplet fonnation, along with a stability analysis of a migrating liquid film in a solid matrix will be given.

A NEll MECHANISM FOR DIFFUSION INDUCED GRAIN BOUNDARY MIGRATION (DIGM): N. Louat, Oxford University, Oxford, England and C.S. Pande and B.B. Rath, Naval Research Laboratory, Washington, DC 20375

(10:10 a.m.)

A new mechanism for t,le diffusion induced grain boundary migration, based on the energetics of the grain boundary 1s proposed. The grain boundary energy 1s assumed to be a minimum for a certain solute concentration. The driving force and the kinetics of the processes are analyzed on this basis. 'nle migration behavior and concentration of alloyed regions are calculated and compared with experimental observations and shown t a be in good agreemen t.

(10:30 a.m.) (8:50 a.m.) THE EFFECT OF NITROGEN ON NUCLEATION AND GROWTH OF CHROMIUM RICH PRECIPITATES AT GRAIN BOUNDARIES IN 304 STAINLESS STEEL:* H.S. Betrabet, William A.I. Clark and Bryan E. Wilde, Dept. of MetallurgIcal Engineering, The Ohio State University, Columbus, OH 43210 Optical metallography and EPR test data have shown that the time required for 304 type -stainless steel to reach a given degree of sensitization increases as nitrogen is added up to 0.16 w/o, and then decreases to 0.25 w/o. In order to determine the mechanism by which nitrogen affects the nucleation and growth of chromium rich precipitates, and the development of associated chromium depleted regions, a series of sensitized 304 stainless steels contai ni ng varyi ng amounts of nitrogen have been characteri zed using weak beam transmission electron microscopy and analytical electron microscopy. The results of this investigation will be presented along with the proposed mechanism which explains this behavior of nitrogen. *Work supported by the DOE under contract #DC-AC02-81ERI0972

HIGH RESOLUTION ELECTRON MICROSCOPY OF HIGH ANGLE COOl] TILT GRAIN BOUNDARIES IN THE BCC METALS:* E.A. Kamenetzky, R. Kilaas, R. Gronsky, Materials and Molecular Research Division, Lawrence Berkeley Laboratory, Berkeley, CA 94720, and Y.T. Chou, Department of Metallurgy and Materials Engineering, Lehigh University, Bethlehem, PA 18105. Bicrystals of Mo and Nb were grown in a vertical floating zone electron-beam melting furnace using a V-shaped seed method. The high angle COOl] near-coincidence symmetrical tilt boundaries were exami ned in HREM with axi a 1 ill umi na ti on and compared with simulated images of various models of grain boundary structure. These studies demonstrate the changes in atomic structure which occur for orientation variations between I = 1 and I = 5, and the results are explained on the basis of dislocation/structural unit model. *Thi s work is supported by the Di rector, Offi ce of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098.

TMS-AIME Annual Meeting Program - 11 (10:50 a.m.) AN EXPERIMENTAL STUDY OF THE EVOLUTION OF CAVITY SIZE DISTRIBUTrOllS DURING GROWT" U,lDER CREEP CONDITIONS." J. Soullard, J. Oseguera and L. Martlnez, Physics Institute, National University of Mexico, Mexico, D. F. The conditions to implant a tiell spaceed distribution of creep intergranular cavities were determined. The distribution of cavity radius was obtained by analizing a big enou~h number of scanning electron microscopy photographs. The statistics was corrected using De Hoff nethods. The cavity implanted specimens were creeD deformed at stresses where nucleation is not likely to occur ~nd durin,g times small eTIolieh to prevent coalescence. The cavity radius distribution was then obtained and compared to the initial distribution. The experimental results are comoared with the evolution of a size distribution modelled with ~avity growth rates predicted by the theories of Trinkaus, Edward and Ashby and Chuang and Rice.

"

Work supported by CONACYT-MEXICO contract PCCB-BNA-020348

HERBERT H. KELLOGG SYMOPOSIUM: Thermodynamics Sponsored by the Physical Chemistry Committee and the Copper, Nickel, Cobalt and Precious Metals Committee Monday, February 25, 1985 8:30 a.m.

Regency Ballroom Sheraton Centre

Session Chairmen: Y. K. Rao, Metallurgical Engineering, University of Washington, Seattle, Washington 98195; V. Kudryk, ASARCO Incorporated, So. Plainfield, NJ 07080

(8:30 a.m.) THE EFFECT OF IRON ACTIVITY AND OXYGEN PRESSURE ON THE COPPER AND IRON TRANSFER IN FAYALITE SLAG AT I200·C, T. Nakamura, B. Chan and

several different and independent rrolecular species (e.g. oxides, sulfides, chlorides). Such a view is ill1tenable in view of the known proven ionic nature of slags.

(10:15 a.m.) MATHEMATICAL DESCRIPITION OF THE THERMOCHEMICAL PROPERTIES OF THE SYSTEM Cu-Bi-Sb: H. H. Kellogg and Y. H. Kim, Columbia University, Seeley W. Mudd Building, 120th Street & Amsterdam Avenue, New York, NY 10027. Mathematical conclusions have been developed for the binaries Cu-Bi,Cu-Sb and Bi-Sb and for the ternary Cu-Bi-Sb. The concept of associated species is used, where appropriate, along with the Margules equations for non-ideal behavior. The correlations faithfully reproduce existing thermochemical data within the experimental uncertainty of the measurements.

(10:45 a.m.) THERMODYNAMICS OF SULFATIZATION OF IMPURITIES IN TITANIFEROUS SLAGS Krzyszof Borowiec and Terkel Rosenqvist. Division of Metallurgy, The Norwegian Institute of Technology,

N-7034 Trondheim-NTH-Norway. With the aim of determining the thermodynamic conditions for sulfatization of impurity elements, in particular magnesium, in titaniferous :lags the chemical activity. of MgO in the 0 ternary system Tl02-Fe20'3-MgO has been studled at 700-1000 C by an EMF technique basea. on the reaction

MgO + S02 + 1/2 O2

=

MgS0 4

and with solid ZrOZ + CaO electrolyte. From the data the Gibbs energy of formation of magnesium titanates as well as their activities in the ternary system are derived. Similar measurements are planned also for other impurity elements.

J .M. Toguri, Department of Metallurgy and Materials Science, University of Toronto, Toronto, Canada, M5S lA4

(11:15 a.m.) ESTIMATION OF THE STANDARD FREE ENERGIES OF FORMATION OF TIN

The transfer of copper and iron between fayalite slag and Cu-Fe alloy has been studied in order to investigate the feasibility of a slag cleaning process using scrap iron.

CHLORIDES:

The copper and iron transfer rates were determined experimentally by analysing the copper content in slag and the iron content in the alloy. The experiments were performed at lZOQoC starting with a fayalite slag containing a known amount of copper and a copper alloy containing from 0.5 to 5 wt %. of iron. It was found that the copper content in slag was rapidly reduced. For example, a slag containing 4.1 wt % Cu, was reduced to less than 1 wt % Cu within 20 minutes, using ,95 wt % Cu-5 wt % Fe alloy. The results indicated that the reduction rate of slag copper and the final copper content in the slag were predominantly controlled by the iron content in the alloy. The mechanism of the copper and iron transfer is also discussed.

(9:00 a.m.) VISCOSITY MEASUREMENTS OF INDUSTRIAL BLAST FURNACE SLAGS: R. Altman, G. Stavropoulos, K. Parameswaran, ASARCO, Inc., 9Ul OakTree Road, South Piainl"ield. N. J. 07080. A Brookfield viscometer fitted with a stainless steel spindle was used to measure the viscosity of industrial blast furnace slags between 1150 and 12500 C. Approximately 2 lbs of slag were held in an alumina crucible under a protective nitrogen atmosphere. Slag samples were removed by suction before and after each viscosity measurement. It was found that contact with the crucible caused the Al203 content of the slags to increase by only I or 2 percentage points. However, partial dissolution of the stainless steel spindle resulted in about a 20% calibration error in the measu.red viscosity towards the end of a 7 hour campaign. This error was substantially eliminated by assuming a proportional correction based on the time the measurements were made.

Slag oxidation state was characterized by first annealing the slag samples at 750°C in sealed copper tubes in order to precipitate magnetite crystals. The concentration of magnetite was then measured on an Outokumpu Saturated Magnetic Analyzer.

(9:30 a.m.) MErAL, MATl'E AND SLAG SOlllTION 'I'HElMXJYNl\MICS: T. R.A. Davey & G.M. Willis, MErl'CON Consulting Services, Victona, Australia. A sinple roodel for Iretal solution behavioor may be derived for nany binary systems, on the basis of dilute region solubilities (where log concentration of solute varies linearly with reciprocal temperature) and oot-so-dilute region solubilities (where tI1ev( -fill1ction at saturation frequently varies linearly with reciprocal temperature) and assuming activity to vary according to the quadratic fonnalism in between. Matte binary systems usually exhibit regular solution behaviour, when the constituent species are chosen appropriately. In nany recent papers, Iretal solubilities in slags are expressed as the sum of

S. S. Guzman, Henry Krutnb School of Mines, Columbia University, New York, New York, U.S.A. 10027.

The standard free energies of formation of tin chlorides were estimated with reviewed and estimated basic thermodynamic data, and measured reversible potentials for the disproportionation of tin dichloride into metallic tin and tin tetrachloride. Values for Co, So, HO_H~ 8' _(Go -H~98)/T, 6.H~, 6.G~, and log Kp are givenPin tabular form; these estimations are compared with estimations reported in the literature.

HUME·ROTHERY MEMORIAL SYMPOSIUM and PHASE DIAGRAMS, ALLOY PHASE STABILITY AND THERMODYNAMIC ASPECTS OF NOBLE METAL ALLOYS I: Hume·Rothery Lecture, Theory of Stability Co-sponsored by TMS Committee on Alloy Phases, ASM Alloy Phase Diagram Data Committee and ASM-MSD Thermodynamics Committee Monday, February 25, 1985 8:30 a.m. Session Chairman: L. H. Bennett,

Versailles Terrace Sheraton Centre National Bureau of Standards,

Gaithersburg, MD 20899

(8:30 a.m.)

Introducing the 1985 Hume-Rothery Memorial Awardee

(8:35 a.m.) THE NOBLE METALS AS INCIPIENT TRANSITION ELEMENTS: R. E. Watson, Brookhaven National Laboratory* I Upton, NY 11973 The traditional Hume-Rothery view of the noble metals is that they can be treated as if they were essentially monovalent free-electron-like metals, when alloyed with elements to their right in the periodic table. Hume-Rothery recognized that the noble metal d-bards particip"ate when these metals are alloyed wi th trans i tion elements. The d bands of the noble metals, and especially of Cu and Au, 'are actively involved in hybridization with the orbitals of the other constituent, be they transition or main-group elements, in alloys. This is essential to the net charge transfer in, as well as to the energetics of, alloying. There is d-charge transfer which is usually accompanied by non-d counterflow. Granted this, the noble metals are partly "transition-metal" like. This view, as it has evolved over recent years, will be inspected with particular emphasis on Au and the neighboring 5d transition metals. *Supported by the Division of Materials Sciences, U. S. Department of Energy under contract DE-AC02-76CH00016.

12 - TMS-AIME Annual Meeting Program (9:35 a.m.) ELECTRONIC AND MAGNETIC PROPERTIES OF NOBLE-METAL AND TRANSITIONMETAL ALLOYS , INTERFACES AND OVERLAYERS: L.M. Falicov, Department of Physics, University of California, Berkeley, California, 94720

*

The electronic properties of noble-metal alloys and overlayers examined. In particular: (I) The ordering and segregation properties of noble-metal noble-metal alloys; (2 ) The ordering and segregation properties of transition-metal

silver alloys; (3)

(4) (5)

The electronic and magnetic properties of nickel-copper alloys; The electronic and magnetic properties of nickel-copper interfaces; The electronic and magnetic properties of cobalt and nickel

over layers on copper are discussed in detail. *1'h15 work was supported in part by the National Science Founda-

tion through Grant No.

D~IR-8l-06494.

(10:25 a.m.) ABINITIO THEORY OF THE ALLOYS· G. M. ~tocks, Laboratory, M. Bori ng, F. J. Pinski and D. D.

ELECTRONIC STRUCTURE OF THE HUME-ROTHERY and J. S. Faulkner, Oak Ridge National Los Alamos Nat i ona 1 Laboratory, and Johnson, University of Cincinnati

Ever since the pioneering work of Hume-Rothery the properties of a-phase CucZnl_c' CucGal_c and CucGel_c alloys have been understood in terms of electron to atom ratio effects. Here we present results of entirely parameter free calculations of the el ectroni c structure and ground state propert i es of these systems based on the KKR-CPA method and density functional theory. We use these calculations as a basis for interpreting low temperature specific heat experiments, Fermi surface measurements, etc. The standi ng of the earl i er semi -phenomeno 1ogi ca 1 models will be reviewed in the light of the modern description.

depends critically on the stability of the rapidly solidified microstructure during subsequent densification and thermal mechanical processing. The status of the rapid solidification-mechanical behavior interface is assessed for a spectrum of ferrous and non-ferrous alloys in order to illustrate when and how mechanical behavior is uniquely attributable to rapid solidification. These examples demonstrate that alloy development via rapid solidification is perhaps the single most important attribute. Current limitations, challenges, and future directions needed to deploy this technology and maximize its potential, will be discussed,

(9 :10 a.m.) RAPID SOLIDIFICATION PROCESSING METHODS:

C. M. Adam,

Materials Laboratory, Allied Corporation, Morristown, NJ. During the last decade alloys of novel composition, prone to severe microsegregation when solidified by conventional casting, have been developed for industrial applications. A variety of industrial techniques have been developed for producing rapidly solidified alloys, all of which produce alloy material of dimensions 10-100 ~m. In many alloy systems solidification commences in a strongly undercooled metallic droplet or film and the surrounding environment allows adiabatic or quasi-adiabatic solidification. Progress has been made in understanding the factors controlling microstructure during solidification of such alloys at high solid-liquid interfacial growth veloci ties. This review will cover the principal systems currently producing rapidly solidified alloys in tonnage quantity, appropriate mathematical models of the solidification process, and factors responsible for the evolution of microstructure. Some applications of rapidly solidified alloys will also be reviewed, from amorphous metallic foils for magnetic device applications, to consolidated powder metallurgy components for structural flpplications.

(9:40 a.m.) CONSOLIDATION OF RAPIDLY SOLIDIFIED POWDERS/PARTICULATES: *

B. B. Rath. Naval Research Laboratory. Washington, D.C. and

~search sponsored by the Di vi sion of Material s Sciences, U.S. Department of Energy under Contract No. DE-AC05-840R21400 with Martin Marietta Energy Systems, Inc.

(11 :15 a.m.) APPLICATION OF THE ANNNI MODEL TO LONG-PERIOD SUPERSTRUCTURES D. de Fontaine, J. Kulik and A. Finel*, University of California Dept. of Mat. Sci. & Min. Eng., Berkeley, CA. 94720. ·Permanent Address: ONERA, Chatillon, France. Existing models of long-period superstructures are reexamined in the 1 i ght of the recentl y developed Ax i a I-Next-Neares t-Nei ghborIsing (ANNNI) Model. In this model, long-period phases are contained in a triangular shaped phase diagram region bounded by a Lifshitz point on the uppermost transition temperature line and a multiphase point at zero absolute temperature. Periodic antiphase structures may be regarded as produced by a square-waverrodulation, resulting in long-period superstructure polytypes, here denoted as "Fujiwara phases." The role of configurational entropy in stabilizing long-period phases is emphasized. The appl icabil ity of the ANNNI model to periodic antiphase structures in ordered noble metal alloys is examined, and the striking resemblance between predicted structures and those observed experimentally in Ag,Mgand Au,Zn for example, is poi nted out. The difference between" stra ight" and "wavy" (CuAu II) antiphase domain boundaries is discussed in the light of the model. A rather complete statistical mechanical calculation of a two-dimensional ANNNI model phase diagram is al so presented.

MECHANICAL BEHAVIOR OF RAPIDLY SOLIDIFIED MATERIALS I: Processing and Testing Techniques Sponsored by the TMS Mechanical Metallurgy Committee and the ASM-MSD Flow and Fracture Activity Monday, February 25, 1985 8:30 a.m.

Regency Foyer Sheraton Centre

Session Chairmen: S. M. L. Sastry, McDonnell Douglas Research Laboratories, St. Louis, MO 63166; B. A. MacDonald, Office of Naval Research, Arlington, VA 22217

J. C. Williams. Carnegie-Mellon University, Pittsburgh, PA The consolidation of powders represents an important step in the microstructure control and tailoring of rapidly solidified alloys. In particular, low temperature consolidation appears necessary if the fine microstructural scale achieved through rapid solidification is to be preserved in the bulk material after consolidation. A variety of consolidation techniques have been studied with such a goal in mind. In this paper we will review the current status of these various consolidation methods. We also will discuss the penalties associated with incomplete consolidation and compare these to the potential benefits. Alternatives to low temperature consolidation will also be considered.

*We gratefully acknowledge the support of DARPA for portions of this work.

(10:10 a.m.)

Break

(10:20 a.m.) TESTING TECHNIQUES FOR MECHANICAL PROPERTY CHARACTERIZATION OF RAPIDLY SOLIDIFIED MATERIALS: C. C. Koch, Materials Engineering Department, North Carolina State UnlVersity, Raleigh, N. C. 27695-7907. Mechanical property testing techniques will be reviewed for rapidly solidified materials. Mechanical testing of rapidly solidified materials is complicated by the fact that in most cases at least one dimension of the material is very small « 100 "m). The review will focus on this problem and the val idity of measurements made on the constrained geometry wi 11 be discussed. Elastic property measurements will be briefly treated but emphasis will be placed on plastic flow, fracture, and fatigue. Microhardness measurement is an important "sur· veying" tool for rapidly solidified materials and one of the few mechanical tests possible on "in situ" rapidly solidified surfaces (pulsed laser or electron beam melting). Techniques for mi crohardness measurements on thi n 1ayers wi 11 be treated. Comparisons between stress-strain behavior on bulk tensile samples and on thin ribbons will be given. (10:50 a.m.)

(8:30 a.m.)

Introduction ENVIRONMENTAL SENSITIVITY CHARACTERIZATION OF RAPIDLY SOLIDIFIED

MATERIALS, S.J. Thorpe and K.T. Aust, Department of Metallurgy and Materials Science, University of Toronto, Canada. M5S lA4

(8:40 a.m.) RAPIDLY SOLIDIFIED MATERIALS -

CURRENT ASSESSMENT AND FUTURE

DIRECTIONS: Alan Lawley, Department of Materials Engineering, Drexel University, Philadelphia, PA 19104 Several attributes of the rapidly solidified state have been clearly identified. These include alloying flexibility, increased solid solubility limits, fine-scale microstructures, and chemical homogeneity. For structural materials in which mechanical properties are of prime importance, the rapidly solidified material, in the form of powder, splat, ribbon, or fiber must be consolidated to full density. Thus, mechanical property integrity

Recent studies on the corrosion behaviour of Fe-, Co- and Ni-base amorphous alloys in ribbon form are used to illustrate several of the methods suitable for determining the environmental sensitivity of rapidly solidified materials. The alloy samples were examined using X-ray scattering intensity measurement, SEM, optical and TEM microscopy. Auger electron spectroscopy analysis was also carried out to determine the surface film compositions and the degree of heterogeneity through the ribbon thickness. The general corrosion characteristics were studied using potentiodynamic and potentiostatic anodic polarization tests in acid

TMS-AIME Annual Meeting Program - 13 solutions. Sample pr~parat ion was considered, part icularly the application of a suitable organic coating to the metallic ribbons for exposure to different electrolytes. To assess the pitting corrosion resistance of these alloys, pit propagating rate and pit deacceleration rate tests were conducted. Crevice corrosion behaviour was. studied using an artifically-created crevice by producing a metal-to-metal sandwich of the amorphous alloy.

described. Experimental results of the progressive development of closure for physically-short and long cracks in a lower strength 2 1/4 Cr-I MJ Stee I are discussed.

(9:10 a.m.) MECHANISM FOR THE FORMATION OF HIGH CYCLE FATIGUE CRACKS AT FCC

ANNEALING TWIN BOUNDARIES, Z.R. Wang and H. Margolin, Polytechnic Institute of N.Y., Brooklyn, N.Y. 11201

(11:20 a.m.) A CRITICAL TENSILE CRITERION FOR FRACTURE IN AN Fe-BASED AMORPHOUS ALLOY: H. Kimura and T. Masumoto, The R~search Institute for Iron, Steel and Other Metals, Tohoku University, Sendai 980, Japan.

A critical tensile criterion for fracture, crf = QOy has been proposed in a bent ribbon of an Fe-based amorphous alloy; this criterion is based on the newly-defined, plastic stress concentration factor (Q). In this paper, we first review local fracture stress (Of) and Q as a function of separation distance for a variety of Fe-base amorphous alloys such as Fe80B20 and Fe80P20, obtained from an analysis of a temperature denepende of bend ductility. Next, we measure a strain distribution at a notch tip in a center-notched specimen of amorphous Fe78SilOB12 in terms of a fine-grating method; and then attempt to analyze surface displacements along slip bands by Dugdale model and a Fourier transform method in order to verify the existence of Q.

When a stress axis is normal to an fcc annealing twin boundary the stress axis is the same in both twin components. However, when the stress axis is inclined. to the twin boundary the stress axis is different, crystallographically, in each component. Since the stress axes are not synunetry axes, elastic shears take place normal to the stress axis in each component of the twin. These elastic ~hears are different in each component and their interaction leads to stress enhancement on slip planes parallel to the twin boundary. It is proposed that this stress augmentation produces the slip adjacent to the twin boundary that leads to high cycle fatigue cracking. Finite element calculations have been carried out for three pairs of orientations. These calculations confirm the enhancement of stress on slip systems parallel to the twinning plane. This research is sponsored by National Science Foundation under Grant *83 12963.

(9:30 a.m.) (11:40 a.m.) DAMPING AND DEGRADATION OF AN A1-Li RAPIDLY SOLIDIFIED ALLOY: P. R. Mantena, N. Perez, R. F. Gibson, and T. A. Place, University of Idaho, Dept. of Mechanical Engineering, Moscow, Idaho 83843.

The properties of an AI-Li rapidly solidified alloy prepared by ribbon casting and powder metallurgy consolidation were investigated. The alloy was evaluated for performance in an application involving sudden and repeated thermal excursions. The deterioration of the material with increasing temperature was characterized by optical and electron microscopy and by mechanical testing. Changes in fracture mode were determined by scanning electron microscopy. The results indicated a deterioration in properties with increasing temperature. The damping capacity of the alloy was measured at all stages of the degradation process. The purpose of this part of the program was to determine if the deterioration of an RSA component could be traced by external NDE tests. Correlations between damping capacity and the mechanical property data are being attempted, and a simple model for the prediction of degradation from damping capaci ty has been developed.

INFLUENCE OF HIP PROCESSING ON THE MICROSTRUCTURE AND PROPERTIES OF CENTRIFUGALLY CAST ALLOY 718: H. H. Smith and D. J. Michel, Naval Research Laboratory, Washington, DC 20375

The relationship between the microstructure of centrifugally cast alloy 718, both before and after HIP processing, and the tensile strength and fatigue crack propagation properties was studied at 400 to 650 u C. The results show that HIP processing reduced the quantity of the Laves phase in the microstructure when compared with the as-cast alloy. Further, the HIP treatment produced complete homogenization of the alloy microstructure in the intermatrix regions. Examination of the fatigue crack propagation results shows that the crack propagation path after HIP treatment was within the matrix with a transgranular character as compared with the as-cast material which exhibited the tendency to crack within the intermatrix regions at higher levels of the stress intensity factor. The HIP treatment groduced a reduction in the fatigue crack propagation rate at 650 C particularly for the alloy cast with a 50 rpm mold speed and a reduction in the tensile ductility. The correlation of the mechanical properties with the microstructural features will be discussed.

(9:50 a.m.)

MECHANICAL PROPERTIES I TMS-AIME General Abstract Session Monday, February 25, 1985 8:30 a.m.

Evaluation of M~ch~nical Anisotropy of Textured Zircaloy Using ImpresslOn lest1ng

Monarch Suite Sheraton Centre

Session Chairman: S. Suresh, Brown Univ., Providence, RI 02912

(8:30 a.m.) A STUDY OF CREEP AND CREEP FRACTURE IN A CLASS I SOLID SOLUTIO. ICu + 5 wt'llo SnH J. S. Wang and W. D. Nix, Dept. of Hat. Sci. and Eng .. Stanford University, Stanford, CAlifornia 94305 Cu + 5 wt" Sn was predicted to be a class I solid solution. Constant true stress creep tnts have been conducted in the temperature range of 0.6 to 0.8 Tm and in the stress range of 2.2 to 130 MPa. In the strRss range 3.5 to 95 MPa, the alloy exhibits Class I solid solution behavior. The stress exponents are n = 3.3 and n = 2.8 for creep and creep fracture, respectively. The activation energies are 171 KJ fmole for creep and 178 KJ fmole for creep fracture, which are close to the diffusion activation energy of Sn atoms in pure Cu 1188 KJ Imole). In the n =3 regime, the alloy shows higher ductility than in the n z 5 and power law breakdown regimes, and creep fracture occurs primarily by inhIYgranular cavitation. Combined with me .... urements of density changH, the higher ductility in the n = 3 regime can be explained in terms of the competition between grain boundary cavitation and matrix deformation. Research sponsored by the Unided States. Department of Energy under contract No. DE-AT03-83ER45024 (8:50 a.m.) EVOLUTION OF CLOSURE FOR SHORT AND LONG FATIGUE CRACKS: CRITICAL ANALYSES INVOLVING CRACK INITIATION IN CYCLIC COMPRESSION": T. Christman and S. Suresh, Division of Engineering, Brown UniverSity, Providence, RI 02912 It is now recogn i zed that closure is one of the factors respons ib Ie for the apparent di fferences ingrowth rates of "short" and "long" fatigue cracks. In this presentation, a novel technique involving crack initiation under cycl ic compression for monitoring the evolution and distance of dominance of crack closure is

K

~?Ue. Hsd~~gonr~~~~Hy ~u~~i~~ ~h?i ~~, ~'6~t 9B89r'c...'-=L-,",in",g.=.a_Mc::.urc..:t,,-Y, ImDress i on test i og was used tQ eva 1uate t~e anj' sotrODi c m~chani­ cal propert1es. Of tUb~-redyc~d extrusjon TREX of l1 rcon1 urn alloyed w1th t1n and 1ron tZ1rcaloy'-4. amples measuring 7mm d7eep by.10 J1III along the diametral ~irection were machined from 11111 th1Ck TREX. Various mechanical properties such as the yield strength, work-h~rdening parameter, elastic modulus were eva 1uated aT ong the aX1 a 1, hoop and radi a 1 di rect ions of the tubing using a flat 1.6 J1III diameter indentor made of hardened 17-7 PH sta1nless steel. To eliminate problems associatead with ~lignment of the load train in impression.testing, a com~res~ion J1g was des19ned such that tens1le operatlon of tlie mach1ne 1S converted to compression at the spec1men location. An LVDT extensometer was attached to the compression jig and the indentQr displacement was monitored in-situ to better than 0.0015 mm. Yleld strength val~es along the.three Orthogonal d1rections faci11 tated an eva 1uat 1on of tlie am sotroRY parameters Rand P whi ch are related to the parameters F, G and H in von Mi ses- Hi 11 yi e 1d criterion for anisotropic materlals. *supported by NSF Grant OMR8313157

(10:10 a.m.) INFLUENCE OF LITHIUM CONTENT AND AGING TREATMENT ON T~E ME01ANICA!? PROPERTIES OF AI-L1-Cu ~Asm ALLOYS: A.K. Vasude van, S. Suresh, M. Tosten3~nd P. Howell, IAIloy Technology Division, Alcoa Center, PA 15069, Division of Engineering, Brown University, Providence, RI 02912 and 3Department of Metallurgy, Penn. State Univ., College Park, PA 16802 The objective of this presentation is to examine the effects of compositional and microstructural variations on the mechanical properties and mechanism of fracture in several high purity aluminum-I ithium allOys. Specifically, this study has been directed at ach i ev i ng the fo I low i ng goa Is: ;) a systemat i c characterization, with the aid of TEM, of the precipitation sequence and microstructure in aluminum alloys with I to 3 wti/. Li and varying arrounts of Cu; ii) analyses of the effect of Li/Cu ratio (0 to about 2,5, in terms of the ratio of atomic fraction of the two elements) on fracture toughness under identical yield strength or identical aging condition. Primary mechanisms of quasi-static fracture in AI-Li alloys are discussed. *Th i s work is supported by the Of f i ce of Bas i c Energy Sci ences, U.S. Departrrent of Energy, under Grant DE-FG02-84ER45 I 67.

14 - TMS-AIME Annual Meeting Program (10:30 a.m.) THE STRUCTURE AND PROPERTIES OF DRAWN DUAL PHASE STEEL WIRE. J. Ahn and G. Thomas, Materials and Molecular Research Division, Lawrence Berkeley Laboratory, Berkeley, CA 94720

An investigation has been made to produce high strength wire from the hot-rolled low carbon dual phase steel as an alternative to conventional pearlite medium to high carbon steel wire. The high work hardening rate and superior cold formability of dual phase steel enable it to be drawn to large strains and into high strength wire without intermediate patent treatment. The relationship bi!.tween the microstructure and mechanical properties of dual phase cold drawn wire will be discussed with particular emphasis on the dislocation substructure and deformation behavior at large strain.

This work is supported by the Director, Office of Energy Research, Of f ice of Basic Energy Sciences, Materials Sciences Division of the U. S. Department of Energy under Contract No. DE-AC0376SF00098.

(10:50 a.m.) THE EFFECT OF FERRITE GRAIN SIZE AND MARTENSITE VOLUME FRACTION ON THE TENSILE PROPERTIES OF DUAL PHASE STEEL: P .·W, Chang, A. G. Preban, Inland Steel Research Laboratories, East Ch1cago, IN The yield strength and tensile strength of dual phase steel are found to follow a Hall-Petch type dependel'ff2 on the mean free path in ferrite, d , i.e. u = u + k d • The Hall-Petch slope k increases with increasing ~oltSlle :taction of martensite, V , in the dual phase in both cases, and u is independent of V t'Br yield strength but increases with V
(11:10 a.m.) TEMPERATURE AND DISLOCATION SUBSTRUCTURE: IMPACT ON FRACTURE TOUGHNESS IN STEEL, R.W. Bush and D.J. Quesnel, Dept. of Mech. Engrg., Materials science Program, University of Rochester, Rochester, NY 14627. It has been shown that dislocation microstructures induced by slight amounts of predeformation in low alloy steel have a profound impact of fracture toughness. The dislocation cell substructure produced by low cycle fatigue may have an even greater effect on fracture toughness due to the relatively open dislocation free spaces between cell walls and the multitude of dislocation sources to accommodate plastic deformation ahead of the crack tip. Preliminary work has been conducted to establish the influence of both cellular dislocation substructures and testing temperature on the fracture toughness of steel using the short rod type specimen.

(11 :30 a.m.)

THE EFFECT OF STRESS-STATE ON THE PROCESSES CONTROLLING CREEP FRACTURE IN LOW ALLOY FERRITIC STEELS: N. G. Needham and T. Gladman, British Steel Corp., Sheffield Labs., Moorgate, Rotherham ENGLAND ' Failu~es of ~lant operating at high temperature are frequently assoc1ated w1th weldments. At weldments not only is the structure different from the parent material but there is frequently a change in section or some irregularity which results in a multiaxial stress system, This paper examines the effect of stress and stress-state on the processes controlling failure in low alloy ferritic steels frequently used in power plant with particular reference to data on two grades, namely a 2\%Crl%Mo steel and a 1%Crl,;%r40 steel. Detailed quantitative metallography has been carried out to detennine the effect of stress and stress-state on the accumulation of intergranular damage in material with structures similar to those found in the HAl of a weldment. These results are discussed in tenns of the influence integranular damage has on creep fracture properties and in particular how the stress-state dependence of cav1ty damage accumUlation is reflected in the creep fracture propert i es.

METALLURGY OF JOINING OF MATERIALS I Sponsored by TMS Physical Metallurgy and Solidification Committees Monday, February 25, 1985 8:30 a.m.

Washington Suite Sheraton City Squire

Session Chairman: Ram Kossowsky, Westinghouse R&D Center, Pittsburgh, PA 15235

(8:30 a.m.) INTRODUCTORY REMARKS: R. Kossowsky. Westinghouse R&D Center, 1310 Beulah Road, Pittsburgh, PA 15235.

(8:45 a.m.) CHARACTERIZATION OF MOLTEN WELD POOL: J. Szekely, T. W. Eagar, J. McKelliget and G. Dunn. MIT, Charnbridge. MA -2139.

A complete understanding of heat and fluid flow in the molten weld pool requires an understanding of processes occurring within the arc plasma itself. Through the simultaneous solution of Maxwell's equations, the Navier-Stokes equation and the heat balance equation in the plasma, one can predict the temperature, fluid flow and electric current fields in the plasma. This permits one to estimate the fraction of heat conducted to the workpiece by the current and by convection. It is further shown that these fields can be perturbed by the introduction of metal vapors within the plasma. Experimental studies confirm that these vapors are not homogeneously distributed throughout the plasma, hence, the complete solution to thi8 problem becomes formidable although not intractable.

(9: 15 a.m.) FACTORS CONTROLLING MICROSEGRATATION DURING WELDING John Brooks, Sandia National Laboratories, Livermore, CA

94550

ABSTRACT UNAVAILABLE

(9:45 a.m.) MICROSTRUCTURE CONTROL THROUGH MULTIPLE WELDING J. W. Morris, Jr., Univ. California-Berkeley, Dept. Materials, Science, Berkeley, CA.

ABSTRACT UNAVAILABLE

(10:15 a.m.)

Break

(10:30 a.m.) CORRELATION BETWEEN SOLIDIFICATION PARAMETERS AND WELD MICROSTRUCTURE:. S. A. David and V. P. Kujanpaa, Oak Ridge National Laboratory, Oak Ridge, TN.

Weld metal quality depends to a great extent on the solidification behavior of the weld pool. Solidification parameters of interest that control weld pool solidification behavior are temperature gradient G and growth rate R (G'R or G/ R ). In addition weld pool geometry and phase relations are important in the development of microstructures. During welding G and R may be affected through variations in beat input and welding speed. These parameters have been found to affect the weld metal microstructure essentially through their influence on growth morphology, phase distribution, and grain shape and size. The paper will review the influence of solidification parameters on the weld metal microstructure. Finally, their effect on weldability and hot cracking will be discussed.

*Research sponsored by the Division of Materials Sciences, U.S. Department of Energy, under contract No. DE-AC05-840R21400 with the Martin Marietta Energy Systems, Inc.

(11:00 a.m.) MICROSTRUCTURAL PARAMETERS AFFECTING LASER WELDING: E.A. Metzbower and P.R. Denney, Naval Research Laboratory, Washington, DC 20375

Laser beam welding is a high energy density, low heat input process that can be utilized to join a wide variety of metals and alloys. In high power laser beam welding a keyhole is effectively drilled through the workpiec.. The keyhole is filled with a vapor and the translation of this keyhole results in the weld zone. The process has a high depth-to-width ratio and a rapid solidification rate. The laser beam selectively interacts with the different phases and the phenomena of fusion zone purification results. The intent of this paper is to

TMS·AIME Annual Meeting Program. 15 relate the changes in microstructural features that occur to the process itself. The changes that occur can be interpreted in terms of the laser beam welding process, fusion zone purification and the relationship between solidification modes and cooling rates. The alloys that have been welded and examined for microstructural changes are: ASTM A36, A7l0; HYBO/lOO; three titanium alloys; and a marine aluminum alloy 5486.

MODELING IN PROCESS METALLURGY I: FLUID FLOW PHENOMENA Sponsored by the TMS Physical Chemistry Committee and the PTDlISS Monday, February 25, 1985 8:30 a.m.

Dominion A Sheraton Centre

Session Chairmen: J. Szekely, Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139; D. R. Poirier, Department of Metallurgical Engineering, University of Arizona, Tucson, AZ 85721

(10:25 a.m.) FLUID FLOW AND CLEANLINESS OF MELT IN CONTINUOUS CASTING TUNDISHES:* Y. Sahai and R. Ahuja, Dept. of Metallurgical Engineering, The Ohl0 State University, Columbus, OH 43210 This work describes a water model study of fluid flow and associated mixing in continuous casting tundishes. The effects of dams and weirs, and/or gas injection at various locations in a tundish model have been studied. The results indicate the effectiveness of gas injection in conjunction with dams and weirs on fluid mixing and flotation of non-metallic inclusions. The significance of these results in industrial application will be discussed. *Work sponsored by National Science Foundation.

(10:50 a.m.) TIlE EFFECT OF GAS EVOLUTION FROM REACTIVE PARTICLES ON THE HYDRODYNAMICS OF. SUBMERGED GAS-PARTICLE JETS: T. W. Chia, Y. W. Chang. M. J. McNallan, Department of Civil Engineering, Mechanics and Metallurgy J University of I l1ino is at Chicago P.O. Box 4348, Ch icago, I L 60680 J

(8:30 a.m.)

In many injection processes or the refining of liquid metals reactive particles are injected which evolve gases beneath the surface of the melt. All of the hydrodynamic models of submerged gas-particle jet behavior which have been presented to date have used inert particles and have not considered the possible effects of gas evolution from the particles on the hydrodynamic behavior of the jet. The behavior of gas jets containing CaS04.2H20 particles injected into molten Pb-Sn alloys or KN03-NaN03-NaN02 salts has been recorded using high speed cinematography. The particles dehydrate at the melt temperature with the evolution of H20 gas. The behavior of these jets is compared with that of jets containing inert particles which were injected under similar conditions. J

Mathematical Model of Fluid Flow Phenomena in Tundishes, N. EI-Kaddah and J. Szekely, Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 A

A flexible three dimensional mathematical model has been developed to represent metal flow in tundishes. The model utilizes the turbulent Navier-Stokes equations and a k-E. model of turbulence, in conjunction with CHAM's Phoenix code. The theoretical predictions are compared with measurements obtained in water models.

This research is supported by NSF under Grant CPE 81 15342.

(8:55 a.m.) EFFECT OF WETTING CHARACTERISTICS IN TUBE AND PACKED BED FLOW: S. Luk, R. Mutharasan and D. Apelian; College of Engineering, Drexel University, Philadelphia, PA. In determining pressure drop and fluid flow behavior of molten metal systems, we freql'.ently use water models and existing correlations which are based on low temperature model systems. One significant fluid mechanic difference (particularly near the wall) between molten metal and water rnod~l systems is the difference in wetting characteristics. In this paper tube flow and packed bed flow are investigated for the case where the fluid is non-wetting to the wall and the packing material in the Reynolds Number region of 10 to 105. Local velocity profiles (measured with a Laser Doppler Anemometer) and pressure drop correlations are developed.

(9: 20 a.m.) MODELING OF MARANGONI CONVECTION IN WELD POOLS: A. Paul and T. DebRoy, Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pa

16802. A mathematical model was developed to calculate fluid flow in weld pools due to surface tension forces. The equations of change were solved to obtain velocity fields and temperature profiles in the weld pools with and without the

addition of a) sulfur and b) selenium. The computed results indicated that the addition of a very small quantity of any of these elements drastically changed the velocity and temperature profiles and affected the weld pool shapes. The computed weld pool shapes were compared with the corresponding independently measured values.

(9:45 a.m.) The Measurement and Prediction of Flow and Turbulence in Induction Furnaces, *N. EI-Kaddah, J. Szekely, **Y. Fautrelle and E. Taberlet, *Department of Materials Science and Engineering Massachusetts lnsti tute of Technology, Cambridge, MA 02139, **Institute de Mecanique de Grenoble, St. Martin d'Heres, BPS3 Centre de Tri, 38041 Grenoble CEDEX, France. Experimental measurements are reported on the velocity fields and turbulence parameters in an inductively stirred mercury pool, using frequencies ranging from 50-5000 Hz. The measurements are compared with predictions using the k-£ model and in general very good agreement has been obtained over a broad range of conditions.

(10:10 a.m.)

9reak

(11 :15 a.m.) ADVANCES IN THE MODELING OF MOLTEN METAL TRANSFERS.

R.A.

Stoehr

and W.-S. Hwang, Dept. of Metallurgical and Materials Engineering, University of Pittsburgh, Pittsburgh, PA. 15261. The Marker-and-Cell Technique has been shown to be suitable for mathematically modeling the rapid, transient flow of molten metal between metallurgical vessels such as occurs during mold filling, or between ladles and converters. This paper deals with approaches to improve the accuracy and extend the usefulness of this technique. The effect of the proper use of "upwind" differencing on the stability and accuracy of the solutions will be explained. This allows the use of viscosities of any value and opens the possibility for incorporating an appropriate turbulent viscosity model into the technique. The effect of "no-slip" vs. "free-slip" boundary conditions at the solid walls will be shown. Comparisons with physical models show that actual conditions lie somewhere between these extremes. Techniques for obtaining the best fitting solution will be discussed. Finally, techniques which reduce the computer demands for solving these problems by using simplified methods for computing the location of the free surface of the

liqUid will be illustrated.

(11 :40 a.m.) FLOW STRUCTURE OF SUBMERGED GAS JETS IN LIQUIDS - MEASURING TECHNIQUES AND LOCAL PARAMETERS: A.H. Castillejos E . and J .K. Brimacombe, Metallurgical Engineering Dept., The University of British Columbia, 309-6350 Stores Road, Vancouver, B.C., V6T 1W5, Canada In the field of gas injection into liquid metals there is a need for the comprehensive measurement of flow parameters describing the local conditions in the gas-liquid zone. The purpose of this presentation is to describe the principles of measurement and the specially developed electronic instrumentation and software used for the simultaneous determination of local gas hold-up, bubble frequency, average bubble veloCity and size, and spectral distribution of the latter two parameters. The technique consists of a two-element electrical res'istivity probe coupled to fast, realtime data processing to identify bubble veloCity related information from the signals produced by the probe. The measuring system has been evaluated experimentally under various injection conditions and shown to be accurate and rapid. Profiles of the flow parameters, for different injection conditions, are presented and the trends observed are discussed.

16 - TMS-AIME Annual Meeting Program MODELING THE EFFECTS OF ENVIRONMENT ON DEFORMATION AND FRACTURE I: Mechanisms and Continuum-Level Models Sponsored by the ASM Technical Activity, "Computer Simulation in Materials Science" Monday, February 25,1985 8:30 a.m.

Diplomat Room Sheraton Centre

Session Chairmen: Alan J. Markworth and John H. Holbrook, Battelle, Columbus Laboratories, Columbus, OH 43201

(10:50 a.m.) MODELING OF HYDROGEN ASSISTED CRACK GROWTH:

R. P. Wei, Lehigh

University, Bethlehem, PA. Modeling of the pressure and temperat-ure dependence for sustainedload crack growth in hydrogenous gases is described. The model gives explicit recognition to (1) the processes that control the rate of supply of hydrogen to the fracture process zone and (2) the role of hydrogen-microstructure interactions in determining the partitioning of hydrogen among the various microstructural elements and the rate of crack growth along these elements. Comparisons with data on AlSI 4130 and 4340 steels in hydrogen and hydrogen sulfide will be shown, and the technological implications of the model will be discussed.

(8:30 a.m.) SOME OBSERVATIONS ON THE MECHANISMS OF EMBRITTLEMENT OF METAlS.

M. H. Kamdar, Benet Weapons Laboratory, Large Caliber Weapons Systems Laboratory, Watervliet, New York

It is clear that the effects of chemically embrittling gaseous, liquid and solid metal environments at or in the vicinity of the crack tip must be important in the process of embrittlement of ductile metals. The crack tip-environment interactions can be absorption, solution, diffusion, environmentally induced plastic deformation at the crack tip and others. In this presentation, a simple model "Reduction in Cohesion at the Crack Tip" will be briefly described and experimental results which provide some support for the model and other relevant experimental resul ts will be presented. Some suggestions also will be made for further experimental and theoretical work in this area of research.

(9:05 a.m.) RECENT ADVANCES IN KNOWLEDGE OF MECHANISMS OF ENVIRONMENTALLYENHANCED CRACKING AND THEIR PRACTICAL APPLICATION, F.P. Ford

D~~l~~l t~· v~~~meS~1e~~;~~%h rafo~~p~~to the phenomena of stress corrosion cracking and corrosion fatigue in ductile alloy/aqueous environment systems, these modes of failure remain a significant economic and safety issue in many industries. This presentation addresses recent advances in understanding of the mechanisms of such cracking and how they can offer quantitative guidance to system design and the formulation of remedies. Future directions are also discussed, with particular reference to the physical and metallurgical factors that hinder further advance in quantitative mechanistic knowledge.

PHASE TRANSFORMATIONS I TMS-AIME General Abstract Session Monday, February 25, 1985 8:30 a.m.

Dominion B Sheraton Centre

Session Chairman: A. D. Romig, Div. 1832, Sandia National Laboratories, Albuquerque, NM 87185

(8:30 a.m.) PHASE RELATIONSHIPS IN Fe-Cr-Ni-Mo ALLOYS WITH 20-2S%Cr, 5-3S%Ni and 3.5-8%Mo: P.J. Grobner, A.MAX Materials Research Center, Ann Arbor, MI.

Four groups of alloys were investigated for their microstructures in the range of 700-1250 C. The first contained 20\Cr and 5%Mo with six nickel levels between 5 and 30%Ni, the second group was based. on 20%Cr and a%Mo with nickel contents from 10 to 35%, the third consisted of six alloys with 25%Cr, 3.5\Mo and 5 to 30%Ni, while the fourth inclUded six alloys composed of 25%Cr, 5%Mo and 10 to 35\Ni. Specimens of the forged and rolled alloys were annealed at 700 C for 2000 h, at aDO C for 500 h, at 900 C for 100 h, at 1000 C for 24 h, at 1100 C for a h, and at 1200 and 1250 C for 4 h and examined metallographically. The presence of intermetallic phases (sigma and chi) was determined by X-ray diffraction analysis, the composition of the phases present was determined by energy dispersive X-ray analYSis and the amounts of the phases were determined by point counting. The results are presented in form of pseudo-binary diagrams for the four groups of alloys with nickel content as the abscissae and temperature as the ordinates.

(8:50 a.m.) (9:40 a.m.) MODELING OF TIlE ELECTROCHEMICAl CONDITIONS IN CRACKS WITH AN EMPHASIS ON CAVITY DIMENSIONS AND ADHERENT GAS BUBBLES:

*

H. W. Pickering, The Pennsylvania State University, Materials Science & Engineering Department, University Park, PA 16802. This paper reviews our understanding of the measured large electrode potentials in crevices. The results of mathematical modeling of mass and charge transport in the electrolyte within cracks reveals that two parameters are responsible: crack dimensions and/or constrictions such as adherent gas bubbles within the crack. Either can sharply change the potential (and ionic concentrations) in the crack to values approaching the limiting electrode potential, in agreement with measured potential gradients in crevices. The impact on crack propagation is great since it is the crack-tip electrode potential which mainly determines which reaction, e.g. J hydrogen absorption vs. anodic metal dissolution, and at what rate it occurs. *This work was supported by the Office of Naval Research, Contract

AN INVESTIGATION OF THE PHASE DIAGRAM AND FREE ENERGY FUNCTIONS FOR THE NI-CR SYSTEM*: ~ and J.M. Sanchez, Henry Krumb School of Mines, Columbia Umversity, New York, N.Y. 10027, USA. The Ni-Cr system is investigated in its full concentration and temperature range. Emphasis is placed on the investigation of the effect of short range order on the calculated phase diagram. Short range order is taken into account by using the Tetrahedron Approximation of the Cluster Variation Method for the solid phases. For the liquid phase, a Bragg-Will iams approximation is retained in the configurational entropy expression. The enthalpy of fonnation is separated into a reference random enthalpy of fonnation and an ordering energy. The latter includes first nearest neighbor effective pair interactions for the A1 phase, and first and second nearest neighbor effective pair interactions for the A2 phase. Comparison between calculated and available thennodynamica1 data will be carried out and discussed. *This work was funded by the National Science Foundation under grant #DMR-82-06195.

No. N00014-81-K-0025.

(9:10 a.m.) (10: 15 a.m.) NUI'.ERICAL AllALYSIS OF CYCLIC STRESS CORROSION CRACK GRCWTH: B. N. Leis and R. Rungt.:;, Bd,.'C, eile' s Columbus Laboratories, 505 King Ave., Colu:nbus, OH ""3201

A model has recently been formulated that predicts environmentally assisted cracking in one geometry based on satisfying conditions for cracking in constant extension rate tests (CERT). The model has been adapted to dissolution controlled cracking. Conditions for cracking require satisfying both a threshold strain and a window in strain rate that promotes cracking, for a given material-environment system. Growth rate is erl'4Jirically determined from the CERT, or analytically from Faraday's Law. The interval history over which these conditions are satisfied in the near crack tip field is then integrated to produce the total cracking time, crack size, etc. This paper discusses key assumptions of the model and demonstrates its use by application to cracking of a steel in concentrated caustic. The application is explored in terms of crack growth predictions based on either linear or nonlinear superposition of olasticity and stress corrosion damage. Use of the model in other applications is discussed in light of current limitations.

THE CONCENTRATION DEPENDENCE OF PAIR INTERACTIONS IN ALLOYS-A CLUSTER BETHE LATTICE APPROACH*:R. Hawkins and J.M. Sanchez, Henry

Krumb School of Mines, Columbia University, New York, N.Y. 10027, USA.

The electronic energy of binary ordered structures stabilized by first and second nearest neighbor pair interactions has been investigated USing the Cluster Bethe Lattice Method. Short-range order self-consistency and electronic self-consistency are both included in the calculation of the alloy ordering energy. The first and second nearest neighbor effective pair interactions are obtained from the short-range order dependence of the ordering energy. The concentration dependence of these interactions and their effect on phase stability is discussed. *This work was funded by the National Science Foundation under grant IIDMR-82-06195.

TMS-AIME Annual Meeting Program - 17 (9:30 a.m.)

(10:50 a.m.)

DETERMINATION OF ISOTliERMAL SECTION IN Fe-Ni-Cr 3%Mo AND Ni-CrMo-5Ue SYSTEMS USING ANALYTICAL ELECTRON MI CROSCOPY, Ratavad ~, C. F. Kl ei nand R R. Mueller, Exxon Researc an rngineering Company, Route 22 East, Annandale, NJ 08801.

PHASE TRANSFORMATIONS IN TERNARY Ti Ni X ALLOYS: K. Edmonds and C.M. Hwang, Department of Metallurgy, Mechanics and Materlals Science, Michigan State Univeristy, East Lansing, MI 48824.

Analytical electron microscopic studies consisting of x-ray mi croana lys is and convergent beam di ffract i on ana lyses were carri ed out to determi ne the phase fi e 1ds and phase boundari es in the Fe-Ni-Cr-3%Mo and Ni-Cr-Mo-5%Fe systems at 1273K. The results show that the 3%Mo addition to the Fe-Ni-Cr system stabi 1 i zes the sigma phase. Me preferent i a lly part it ions to the sigma phase and the concentrat i on of Mo vari es from 1 wt% in the austeni te to 8 wU in the sigma phase. In cont rast, the addition of 5% Fe to the Ni-Cr-Mo system does not affect the phase boundaries and Fe partitions equally between the austenite and the si gma phase. The resul ts of the study showed that it is not always possible to determine constant concentration sections of quaternary additions by electron microscopic analysis. Only in cases where the quaternary element partitions equally amon~ ~g~cln~ar~i~bn eJ:g:fg~. microscopy analysis provides a constan

Martensitic and charge density wave (COW) transitions in TiNiX alloys are studied using, electrical resistance versus temperature measurements, electron diffraction and microscopy, DSC and X-ray diffraction. The TiNiX shape memory alloys studied, consist of component X being AI, Fe and Cu. Comparing the transfonnation temperatures of these alloys, the higher the Cu content, the higher the transfonnation temperatures. From previous studies, this is just the opposite for the TiNiAl and TiNiFe alloys. The electrical resistance of the martensitic transition increases for the TiNiCu alloy from Ms to Mf, just the opposite of TiNiAl and TiNiFe alloys. Thermal cycling and aging effects are being investigated and will also be presented.

(11:10 a.m.) THE EFFECT OF Be ON CLUSTER-GP ZONE FORMATION IN AI-3%Cu ALLOY:.

J. Karov and W.V. Youdelis, Dept. of Engineering Materials, University of Windsor, Windsor, Ontario, Canada, N9B 3P4.

(9:50 a.m.) CHEMICAL 11IERMODYNAHIC REPRESENTATION OF : Oak Ridge National Laboratory, Oak Ridge, TN

T. B. Lindemer,

Ceria 1s one IDember of the famIly of lanthanide and actinide oxides that have the calcIum fluorite structure, extensive oxide-oxide solid solutions, and large deviations from stoichiometry. The entire T-x-p~ data base for the actinide and lanthanide oxides bas been retrievea from the literature; here T 1s temperature in kelvin and p~ is the oxygen pressure divided by the standard-state pressure. 2Ongolng studies are representing these data by chemical thermodynamic models usually applied to solutions of the metals. Previous work resulted In representations of the T-x-P~2 behavior of the , ' and solutions. The representation of the T-x-P~2 behavior of the xystem will be given here, along with thermodynamic calculation of portions of tbe Ce-o phase diagram. (Research sponsored by the Division of Materials Sciences, U.. S .. Department of Energy, under contract DE-AC05-840RlI400 with the Martin Marietta Energy Systems, Inc.)

(10:10 a.m.) QUANT ITATI VE MEASUREMENTS OF ANOMALOUS SMALL ANGLE X-RAY SCATIERING (ASAXS) IN AI-Zn-Ag ALLOYS. O. Lyon, B. Clark, B.E.C. Davis, J.J. Hoyt, R. Pro, D. de Fontaine, Dept. of Materials Science & Mineral Engr., University of California, Berkeley, CA. 94720. We have performed ASAXS exper i ments on A I-Zn-Ag a I loys us i ng the synchrotron radiation facil ity at Stanford (SSRU. By varying the x-ray energy near the Zn absorbtion edge (j .e. from 8.5 to 9.6 keV), we observed a decrease in the ASAXS intensities, due to the decrease of the Zn atom i c scatter i ng factor. The measurements were performed with a position-sensitive I inear detector whose response versus position, x-ray energy and flux was carefully measured. After a I I correct Ions were made, we found as expected that the binary AI-Zn ASAXS spectra were proportional to (6F)2, H denoting the difference between AI and Zn atomic scattering factors. The analysis of the ternary alloys enabled us to pos i t i on three-t ie-I i nes on the A I-Zn-Ag metastab I e phase diagram. A complete determination of the pair correlation functions is, therefore, possible, provided that the experiments are conducted at both the Zn and Ag absorbtion edges.

(10:30 a.m.) DII . . . . til' ... CODIIIII! cole DCLlJ81. . D ... cole ·. . .1...

Ta•• y S. Ulecu.be and J.W. Morri., Jr., Lawrence Berkeley Laboratory and Dept. of Materials Science and Mineral Eng., University of California, Berkeley, CA 94720 The energy of a coherent inclusion in an elastic solid is the sum of two contribution.: the elastic energy. which is minimized when the inclusion haa the form of a thin plate, and the surface energy, which (assuming isotropy) is minimized when the inclusion is spherical. The two contributions can be analyzed for the case of an anisotropic elastic medium using the Khatchaturyan formulation of the elastic energy of the inClusion, and are found to SUlD. in such a way that the inclusion is exactly spherical when it is saall and spreads into a plate of increasing aspect ratio as it grows. The shift frail a sphere to a plate occurs at a critical value of a dimensionless parameter that depends on the surface tension, the volume change on forming the inClusion, and the elastic constants.

*

This work was 8upported by the U.5. Dept. of Energy under contract #DE-ACOJ-76SF00098.

The GP zone formation in supersaturated AI-3%Cu-O.l%Be and Al3%Cu alloys was investigated at room temperature and at 110oC, using TEM and microhardness methods. The hardening rate for AlCu-Be alloy .is much faster compared to Al-Cu alloy, and the hardness after aging is comparable to that of GP zone fornation in AI-Cu alloy. However, the streaks in electron diffraction patterns with their corresponding needle-like patterns in bright field micrographs, characterizing GP zones in AI-Cu alloys are not present in AI-Cu-Be alloy when aged at IIOoC. An additional aging treatment at ISOoC is required to form these standard GP zones in Al-Cu-Be alloy. It is proposed that Be addition increases the rate of cluster formation and consequently the hardening rate, through an increase in the nucleation entropy.

*

Work supported by the Natural Sciences and Engineering Research Council of Canada r Grant A0836.

(11:30 a.m.) CLUSTER VARIATION STUDY OF TWO AND THREE-DIMENSIONAL ANNNi MJDELS. A. Finel* and D. de Fontaine, University of.California, Dept. of Materials Science & Mineral Engineering, Berkeley, CA. 94720. *Permanent Address: ONERA, Chatillon, France. Many alloys are known to exhibit spatially modulated phases in which the modulation is related to some relevant parameter (temperature, concentration) in a complex way. The Axial-Next-Nearest Neighbor (ANNNI) Ising Model is one of the simplest statistical model which displays such characteristics as long-period COmmensurate phases, aLi ftshitz poi nt, incollJllensurate phases. We present some resul ts obtai ned by us i ng the Cl us ter Vari ati on Method appl ied to the 2-dimensional case as a first step towards the understanding of the ANNNI model on a 3-dimensional lattice. The results are in good agreement with these obtained by other methods (r>1onte-Carlo simulation, free Fermion approximation). In particular, the analysis of the susceptibility in reciprocal space allow us to prove the non-existence of a Lifshitz point (in 2Dim.) and the occurence of an inconmensurate phase region. We are presently extendi ng the ana lysi s to the 3-dimens i ona 1 case.

PROCESSING METHODS AND PROPERTIES OF ADVANCED CERAMIC MATERIALS I Sponsored by the TMS Chemistry and Physics of Metals Committee Monday, February 25,1985 8:30 a.m.

Georgian Ballroom B Sheraton Centre

Session Chairman: F. V. Nolfi, Jr., U.S. Dept. of Energy, ER-131, GTN, Washington, DC 20545; B. J. Berkowitz, Exxon Research and Engineer· ing Co., Box 101, Florham Park, NJ 07932 (8:30 a.m.) CERAMICS AS Et«iINEERIt«i MATERIALS: FLAW FREE PROCESSING; .!h. Kent Bowen, Massachusetts Institute of Technology, Materials Processing Center, Room 12-007, Cambridge, Massachusetts 02139 There a re many app 1{cat ions of cerami cs in hi gh technology engineering systems (high value-added components, chip carriers, waveguides, capacitors, cutting tools, etc.) which will result in significant growth of the ceramics business if the materials research triad, structure-property-processing, moves from the laboratory into the manufacturing plant. Each component can be classified by function (e.g., thermal, optical); configuration (e.g., film, monolith, composite); or processing route (e.g., powder processi ng and crysta 1 growth). Thi rty years o! research have shown that the critical physical/chemical propertles are strongly related to the structure on one or more levels: few angstroms -- crystal structure and phases; 10-100 R -- boundary or grai n boundary 1ayers or phases; 1 ~m -- gra ins i ze, porosity; and macro-structure. The major focus of this overview relates to issues of reliability and reproducibility in processing polycrystalline ceramics and its relationship to the control of the structure and properties.

18 - TMS-AIME Annual Meeting Program (2:30 p.m.)

(9: 15 a.m.)

LASER BEAM

WELDING OF

TITANIUM:

E.

A.

Met'bower and

P. E.

CONSOLIDATION AND PARTICLE Pl\CKING, G. Y. Onoda, ,Jr.,

Denney, Naval Research Laboratory, Washington, DC 20375

Heights, '1Y.

Laser beam welding of thick sections invariably results in the solidification mode changing from the top of the weldment to the bottom. This is a consequence of constitutional supercooling and can be rationalized in terms of heat flow. In weldments of alpha titanium, the solidification mode can not be easily observed in a polished and etched cross section. In order to determine the effect of constitutional supercooling on the properties of the weldments, subscale mechanical property specimens were machined from the top, middle and bottom sections of the weldment. At the same locations, quantitative microstructural analyses were made. Comparisons between the properties and the microstructural features as a function of distance through the thickness of the weldment will be made for weldments fabricated with different parameters.

IB~ Thomas J.

Watson Research Center~or1C£Own-----­

The basic forces that affect the consolidation and packing of ceramic oarticles are reviewed.

These

include surface chemical forces and externally aoplied forces modified by the presence of liquid. Important variables that affect the forces, and therefore the consolidation and packing behavior, are described.

(9:55 a.m.)

Break

(10:05 a.m.)

(3:00p.m.)

PLASMA SINTERING OF CERAMICS: D. Lynn Johnson, Department of

Materials Science and Engineering, Northwestern University, Evans ton J IL Aluminum oxide has been sintered in induction coupled (rep) J microwave induced (MIP) and hollow cathode discharge (Hen) gas plasmas, and magnesium oxide has been sintered in the MIP. Isostatically pressed rods have been passed throught the plasmas at rates of from 1 to 6 em/min, resulting in linear shrinkage rates on the order of I to 4 %/s. Maximum specimen temperatures were as high as just below the melting temperature. Final densities of the alumina were signific-antly enhanced by the addition of MgO, exceeding 99.5% of theoretical. Grain sizes were typically 2-5 urn for the MgO-doped specimens. Specimen heating was influenced strongly by the type of gas employed, being minimum in Ar and greater in diatomic ~ases.

HEAT AFFECTED lONE SOFTENING IN TI-6211: S. Ankem and S. R. Seagle, RMI Company, Niles, OH 44446; G. K. Scarr and J. C. Williams, Carnegie-Mellon University, Pittsburg, PA 15213 A beta annealed o'ne-inch thick plate of Ti-6Al-2Cb-lTa-0.BMo was TIG welded with matching fill er metal, Hardness measurements across the weld revealed softening in the weld heat affected zone. Chemistries, microstructures and submicrostructures of the base metal, HAl and weld zone were compared to determine--reasons for the softening behavior, Details of the investigation will be presented.

(3:30 p.m.) EVALUATION OF TENSILE FLOW PROPERTIES OF WELDMENTS IN TITANIUM

ALLOYS: M.A. Imam, R.W. Judy, Jr., and B.B. Rath, Naval Research Laboratory, Washington, DC 20375

(10:45 a.m.)

VAPOR TRANSPORT AND MICROSTRUCTURE DEVELOPMENT IN CERAMICS, D. W. Readey, The Ohio State University, Columbus, OH During sintering of ceramic powder compacts the path of microstructure development depends on competing transport processes and the interaction between grain growth and densification. Most transport processes are not well understood and controlled with the exception of vapor transport. Vapor transport can be enhanced with a reactive atmosphere with sigificant changes in microstructure. The resul ts of enhanced vapor transport on the development of microstructure in several oxide systems is presented and discussed in light of existing models.

Mechanical property evaluation of weldments is a very difficult task because the failure often occurs in the base metaL Even when failures occur in weld metal, data are inconclusive because of unsymmetrical flow due to local differences in microstructure and chemistry leading to variations in properties. The impression tests, in which a cylindrical indenter of I to 2 mm diameter is penetrated into the specimen at constant speed, have been used to study the behavior of weldments in titanium alloys. Results show that the yield strengths, for example, may vary as much as 20% between the base metal and the fusion zone and the work hardening exponent as much as 8%. These results are discussed in relation to mechanical propert ies measured by conventional tests.

(4:00 p.m.) THE EFFECT OF SOFT-LAYER THICKNESS ON THE MECHANICAL PROPERTIES OF TITANIUM WELDED JOINTS: M. E. WELLS, DTNSRDC, BETHESDA, MD

MONDAY PM

ADVANCES IN TITANIUM WELDING II: Structure/ Property Relationships Sponsored by the TMS Titanium Committee Monday, February 25, 1985 2:00 p.m.

Jefferson Suite Sheraton City Squire

Session Chairmen: O. Arora, Office of Naval Research, Code 431, 800 N. Quincy Street, Arlington, VA 22217; D. F. Hasson, Dept. of Mechanical Engineering, U.S. Naval Academy, Annapolis, MD 21402

(2:00 p.m.) MICROSTRUCTURAL DEVELOPMENT AND NEAR-THRESHOLD FATIGUE CRACK GROWTH BEHAVIOR IN THICK TITANIUM WELDMENTS: J. E. Hack, A. McMinn, K. S. Chan, and G. R. Leverant, Southwest Research Institute, San Antonio, TX 78284 Mi cros tructura 1 development and near-threshol d fati gue crack growth behavior as a function of welding process have been studied in thick weldments of Ti-6Al-2Nb-1Mo-0.8Ta. Deep GasTungsten-Arc, Standard Gas-Metal-Arc, Extended Electrode GasMetal-Arc and Electron Beam welds were investigated. It was found that the microstructures of the HAl and fusion zone regions fall into two classes: 1) a coarse large colony structure typical of the slow cooling experienced by the extraordinarily thick weld bead of the Deep Gas-Tungsten-Arc Weld; and 2) feathery, aligned alpha-beta platelet structure in the HAl and Widmanstatten alpha in the fusion zone typical of the other three welds. Grain boundary alpha phase was found in the fusion zones of all the welds. Crack growth behavior in the fusion zone did not seem to be influenced by the difference in the two types of mi crostructure.

The effect of soft-layer thickness on the mechanical properties of titanium alloy Ti-6AI-4V welded with commercially pure titanium was studied. Welded joint performance was evaluated by tensile tests, notch toughness and fracture toughnesa tests. From the soft interlayer weld model, theoretical relationships for calculating the strength of a jOint using a low yield strength filler metal are reviewed. Experimental results are compared with theoretical predictions of joint strength, and narrow groove joint dimensions for 100% joint efficiency with Ti-6Al-4V base metal are identified. Surface strains in the baseplate and weld metal were monitored during tensile testing and the different stress-strain characteristics between Ti-6Al4V and CP titanium are examined. The behavior of a narrow groove undermatc::hed weld joint was modeled by a 2-D elasticplastic finite element program. A brief discussion of the program is given and a comparison of computed results with experimental data is provided. The effect of constrained plastic flow on weld joint toughness is also discussed.

(4:30 p.m.) STRUCTURE/PROPERTY RELATIONSHIPS IN DISSIMILAR TITANIUM ALLOY WELDS: J. Suh and W. A. Baeslack III, Department of Welding Engineering, The Ohio State University, Columbus, OH 43210 The structures and mechanical properties of autogenous gas tungsten-arc welds and simulated weld structures between the a1phabeta alloy Ti-6Al-4V and the metastable-beta alloy Ti-15V-3Cr3Al-3Sn have been studied. Actual weld fusion zone structures exhibiting equal amounts of each base alloy were found to exhibit martensite and retained beta phases in rapidly-cooled automatic welds and alpha plus retained beta phases in slow-cooled manual welds. Using a G1eeb1e 1500 System, simulated weld fusion and near heat-affected zone structures were generated systema;iically for a range of cooling rates from approximately 2 to 100 CIs. The effect of cooling rate on weld structure and tensile properties, and fracture behavior was evaluated. Dilatometry and thermal arrest techniques were used to better understand the beta decomposition reaction during cooling.

TMS-AIME Annual Meeting Program - 19 ALUMINA & BAUXITE I: Alumina Raw Materials Sponsored by TMS Light Metals Committee Monday, February 25,1985 2:00 p.m.

Royal Ballroom B Sheraton Centre

Session Chairmen: Lester Chin, Aluminum Company of America, P.O. Box 300, Bauxite, Saline County, AR 72011; M. Chaubal, C.O. P.O. Box 9911, Corpus Christi, TX 78469

(2:00 p.m.) INTERNATIONAL TRADE IN ALUMINUM ORES: OPTIONS AND CONSEQUENCES, V. Hill, S. Ostoj ie, R. Kalpoe. International Bauxite Association, P.O. Box 551, Kingston 5, Jamaica. Alumjna production costs are estimated for Western World Bayer plants producing metal grade alumina. The results show that bauxite J energy and capital charges are the principle cost factors, however J the relative importance of each is site specific. The data also show that newer plants with higher fixed charges and lower variable charges are operated near capacity while older plants with lower fixed charges and higher variable charges become swing plants. Becau,se plants in developing countries are usually older, labor requirements are usually very high. Consequently, developing countries need to modernize these plants in order to increase their productivity, product reliability and reduce production costs. Bauxite exploited to offshore plants should be priced on assumed alumina production costs in plants using the best proven technology.

(2:30 p.m.) BENEFICATION OF BAUXITE TAILINGS by S.A. Hinds K. Husain and N. Liu., Guyana Min-i_ng Enterprise Ltd. Linden, Guyana, South America. In Linden when crude bauxite is washed to reduce silica one third to one half of the crude is removed. A concentrate of nominal size, -10 +325 mesh, recovered from the washings contains 5 to 15% 8i0 2 . The grains of the concentrate are well liberated. Grains of kaolin, quartz and black sands accompany the desired grains of gibbsite. Concentrates treated with oleic acid showed possibility of separation by various methods. Froth flotation was selected for detailed study and the effect of various parameters determined. At pH 10.8, 90-95% of the gibbsite is recovered in the froth; 90-99% of quartz, 50-80% of kaolin, and 70-90% of black sands are left behind. The cleaned concentrate of 2 to 3% 8i0 2 is a premium grade bauxite for non metallurgical or metallurgical use.

(4:30 p.m.) ALUMINA VIA THE HYDROCHLORIC ACID LEACHING OF HIGH SILICA BAUXITES - PRELI:1INARY ECONOMIC EVALUATION

D. Elsner, D.H. Jenkins and

H.J.~.

Sinha

CSIRO Division of Mineral Chemistry, P.O. Box 124, Port Melbourne, Victoria, Australia, 3207. Tne CSIRO Division of Mineral Chemistry nas investigated alumina production from high reactive-silica bauxite by a hydrochloric acid leaching route. T,lls paper discusses the capital and operating costs for the process when using calcined or uncalcined bauxite as the feed material. Data obtained from technical-scale tests were used to develop energy and material balances as well as equipment sizes. The capital cost of the proposed process for a plant producing dOO,OOO tpa of cell-grade alumina (in 1981 Australian dollars) is $790 per tonne, while tl1e operating cost is $145 per tonne. A comparison of the capital and operating costs of the HCQ. process with the Bayer process as a function of tile reactive silica content of the bauxite is included in the paper.

(5:00 p.m.) OF ALui... LnU:.; OXIll~ J\i~i.1 IUU~, rHO;'1 OHES DASING 0;; T.
C.. .LCllfi,.

ALU;'.lI.i~ATES:

Polymorphic transformations of calcium aluminate (12 CaO, 7A1 20 ) playa key role in the formation of a " se lf-disintegfating" sinter when applying the Grzymek Process to the recovery of alumina, iron and cement from iron rich laterite ores. This transformation phenomena was investigated at different temperatures and under oxidizing and reducing atmospheres using microscopic and x-ray techniques.

ALUMINUM REDUCTION TECHNOLOGY II: Alternative Processes Sponsored by TMS Light Metals Committee Monday, February 25, 1985 2:00 p.m.

Royal Ballroom A Sheraton Centre

Session Chairmen: R. D. Zabreznik, Kaiser Aluminum & Chemical Corp., P.O. Box 1600, Chalmette, LA 70044; R. Schoener, Aluminum Company of America, Alcoa Laboratories, P.O. Box 772, New Kensington, PA 10568

(2:00p.m.) (3:00 p.m.) PLASTICITY IN JAMAICAN BAUXITE: A.H. Wood, Alcan Jamaica Company, Kirkvine Works, Ja. W.I.

The paper briefly reviews the concepts of Plasticity, Plasticity Index, Upper and Lower Plastic Limits as defined in soils, clays and other sediments by the Atterberg Limits Hethod. The use of this technique to identify and measure the plastic properties of Jamaican bauxite is introduced. The possibility of a co-relation between the plastic properties displayed by selected bauxite samples and their chemical compositions is investigated. The impact of these plastic properties on the grinding/dispersing abilities of Jamaica bauxite is studied on bench and plant scales-.

(3:30 p.m.)

Break

PHYSICOCHEMICAL PROPERTIES OF CRYOLITE AND CRYOLITE ALUMINA MELTS WITH KF ADDIpONS. 1. TEMP~RATURE OF PRIMARY CRYSTALLIZATION. R. Fernandez, K. Grjotheim and T. elstvold, Institute of Inorganic Chemistry, The Norwegian Institute of Technology, University of Trondheim, N-7034 Trondheim-NTH, Norway.

As a part of a long run program being carried out at this tute to investigate the physicochemical properties of low electrolytes, the temperatures of primary crystallization cryoli te-rich side of the Na3 AIF6-KF and Na3 AIF6-AI203-KF

Instimelting of the systems

have been determined by thermal analysis. KF addi tions decrease the temperature of primary crystallization of Na3 AlF 6 and Na3 AIF6Al 0

similar to the decrease produced by LiF additions.

While

th~ ~olubili ty of alumina in cryolite is decreased by the addi-

tions of LiF, a slight increase in solubility has been observed when KF was added. Permanent adress: 1. Ardal og Sunndal Verk a.s, N-5875 Ardalstangen, Norway 2. Departmertof Chemistry, University of Oslo, Blindern, Oslo 3, Norway

(4:00 p.m.)

(2:30 p.m.)

KINETICS OF THE SODIUM ALUMINATE FORMATION FROM COAL WASTES USING THE LIME -SOOA SI NTER PROCESS: R. Padi 11 a and H. Y. Sohn, Department of Metallurgy and Metallurgical Engineering, University of Utah, Salt Lake City, Utah 84112-1183

PHYSICOCHEMICAL PROPEHTIES OF CRYOLITE AND CRYOLITE ALUMINA MELTS 1 WITH KF ADDI;pONS. 2. DENSITY AND SURFACE TENSION: R. Fernandez. K. Grjothe1m and T. elstvold, Inst1tute of Inorgan1c Chem1stry, The Norwegian Institute o fTechnology, University of Trondheim, N-7034 Trondheim-NTH, Norway.

The formation of sodium aluminate phase in the sintering stage in the 1ime -soda sinter process app 1i ed to a 1umi no-s i 1i cate materi a 1s is important because it controls the yield of alumina from such materials. This paper describes the kinetic study of sodium aluminate formation in the course of lime-soda sintering of domestic coal wastes. In this system, sodium carbonate directly reacts with alumino-silicate without first decomposing to sodium oxide. The nuc 1eat i on and growth ki net i cs equat i on was used to correlate the experimental data obtained under atmospheric pressure in the temperature range 1000 to 1200°C. An activation energy of 286 kJ/mole has been calculated for fine coal waste powder mi xtures.

*This research was supported in part by U.S. Bureau of Mines under Grant Nos. G5195049, G510589, and G5115493.

As a part of a long rW) program being carried out at this Institute to investigate the physicochemical properties of low melting electrolytes, the density and surface tension of the cryol i te-rich side of the Na AIF -KF, Na AIF -A1 20 3 and Na3 AIF6 -KF-Al;:,o3 systems have been dete~mingd by t5e .J.chimeaean and the pin de~achment techniques, respectively. Both density and surface tension of Na AlF decrease upon addition of KF. The same effect is observed wh~n K~ is added to Na AIF -AI mixtures. As a potential additive to the electrolyttc bgth,2Kr will improve the separation of the metal deposited from the electrolyte and the anode will be better wetted by the electrolyte.

°

-Pe-r-man--en-t ~-ad;-;d-re-s-s: - -

1. Ardal og Sunndal Verk a.s, N-5875 Ardalstangen, Norway 2. Dept. of Chemistry. Univ. of Oslo, Blindern, Oslo 3, Norway

20 - TMS-AIME Annual Meeting Program (3:00 p.m.) CHEMICAL THERMODYNAMIC CONSIDERATIONS ON ALUMINUM BLAST FURNACE H. Yokokawa, M. Fuj ishige, T. Kameyama, S. Uj iie, M. Dokiya Kational Chemical Laboratory for Industry, Tsukuba 305. Japan

A chemical thermodynamic analysis was made to clarify the possible aluminum content in an Al-Fe-S1 alloy to be produced in an aluminum blast furnace. Emphasis was placed upon the stabili ty of liquid aluminum alloy characterized in terms of the thermodynamic activity of aluminum. On one hand. the reduction equilibria provide the maximum aluminum activity in the alloy to he produced in the presence of iron and other metals. On the ()ther hand, the volatilization equilibria between carbon

monoxide and liquid aluminum alloy give the minimum activity of alumi.num to volatilize with the counter-current carbon monoxide flow. Comparison of the two criteria led to the important i inding that the volatilization criterion is much more severe than that of reduction. The composition region in which ,\l-Fe-Si can be produced was evaluated and compared with our recent experimental results in a small carbon combustion furnace.

3:30 P.M. Break 3:45

P.M.

THE DEHYDRATION OF AlCI 3 '6H 2 0 USING CHLOROALUMINATE MELTS' C. B. Mamantov, T. M. Laher, R. P. Walton and G. Mamantov

Department of Chemistry, Uni versi ty of Tennessee, Knoxville, TN The ALCOA Smelting Process involves the use of anhydrous AlCI 3 • This material is usually produced by the carbochlorination of Al203. A number of minerals can be readily transformed to AlC13- 6H2 0. The heating of this hydrate normally results in the formation of aluminum oxide. We have studied the reaction of AICI3' 6H20 with AlCl3-NaCl melts and HCl with the hope of

devising a method for producing a source of anhydrous AlCl 3 • It was found that the following reaction occurs in molten NaAlCl4 at 175 -

200·C AlCl3'6H20

+

5 NaAlCl 4

+

NaCl + 12 HCl

+

6 NaAlOCl2'

The removal of the oxide species from the melt by treatment with anhydrous HCI was found to occur at temperatures of 180 - 200°C according to NaAlOCl2

+

2 HCl + NaAlCl 4

+

H2 0.

Oxide determinations indicate that it is possible to remove - 90% of the oxide by sweeping dry HCI through the melt for 3 hours. Longer HCI sweeps result in only marginal improvement. *This work was supported by the Atlantic Richfield Company

4: 15 P. M.

ALUlilll'lllTlil "L"C'l'ROLY"rS AT LCJ\iErl 'fEi.lPErtA'fUriE,,: L: .l.iiu, hi.Ho, ... Lee, !\I. Zhang. Northea:;t Institute of Technology, Shenyang, China PH

The freezing point of cryolite-alumina melts with additives of AIF3, CaF2, I\1gF2 and LiF was measured. There id a wide range of lower freezing points .below 700·C. Variou:; physico-chemical and electrochemical properties at 50'C above the corresponding m.p. were studied. Current efficiency wa:; high, 85-':10" at 800650'C ~n a laboratory 100A cell. The carbon consumption was low. It i~ a~sumed that aluminium electroly~is with cryolite-alumina meltd may be carried out at 600-650'(; with lower energy con:;umption. 4:45

P.M.

USE OF T1B2 CATHODE MATERIAL - DEMONSTRATED ENERGY CONSERVATION IN VSS CELlS: A.V. Cooke and W.M. Buchta, Martin Marietta Laboratories, 1450 S. Rolling Rd., Baltimore, Maryland, 21227 A new durable carbon/TiB 2 material was tested and proven in a preliminary trial at The Martin Marietta Aluminum plant, The Dalles, OR. Ongoing metal analysis for titanium and boron has shown uniform and slow coating wear, dominated by the solubility of TiB2 in molten aluminum. Significant energy efficiency benefits were al so noted for the TiB2 coated cell s compared to the rest of the pl ant, but in the absence of a val id group of control cells, it was not possible to draw firm conclusions. A fully-controll ed and mon i tored l2-cell experiment was therefore set up at the Martin Marietta Aluminum, Goldendale, WA plant to investigate the improved energy efficiency. After 18 months in service the test cells have shown consistent benefits relative to the control cells, the cell line and the plant. The observed advantages are largely attributed to improved cathode current distribution and a cleaner cathode surface. This results in a quieter metal pad which allows the cell to be operated at lower set voltage.

CARBON TECHNOLOGY I Sponsored by the TMS Light Metals Committee Monday, February 25, 1985 2:00 p.m.

Georgian Ballroom A Sheraton Centre

Session Chairmen: P. G. Campbell, Alumax of South Carolina, P.O. Box 1000, Goose Creek, SC 29445, Buford H. Pippin, Gulf Oil Products Company, Lake Charles Calcining Plant, P.O. Box 3187, Lake Charles, LA 70602

(2:00 p.m.) OXIDATION OF CALCINED PETROLEUM COKES - R. E. Gehlbach and J. T. Gee, Great Lakes Research Corporation, Elizabethton, TN. Oxidation characteristics of calcined delayed petroleum cokes having a wide range of impurities, structures, and bulk densities have been studied using both static and dynamic (continuous weighing) reactivity tests. In addition to evaluating the! effect of these variables on the oxidation rates of granular coke, the effects of test temperature and coke processing history on measured reactivity are included. Advantages of dynami c react i vi ty tes t i ng are di scussed.

(2:30 p.m.) THE IMPACT OF THE CHANGE OF COAL CARBONIZATION AND TAR DISTILLATION TECHNOLOGY ON THE PROPERTIES Of INDUSTRIAL PITCHES; G. R. Romovacek, Koppers Co., Inc .• 440 College Park Dr., Monroeville, PA 15146. Two types of ovens are used for the production of coke. In nonrecovery ovens, all volatiles are burned to generate heat. These ovens were replaced by by-product ovens yielding tar and coke oven gas besides of coke. Due to the different design of coke ovens and operati ona 1 practi ces a imi ng a t the increased productivity, the tar vapors in American coke ovens, compared with those in Europe and Japan. are more cracked and, consequently, more aromatized and contain higher concentrations of QJ. Tar was originally distilled in batch stills, where secondary QI was formed. The original binder specifications were based on pitches produced from these uni ts. When petroleum type sti 11 s were accepted by tar distillers, no secondary QI was formed during the distillation. Therefore, a heat treating step was added in Europe and in Japan to meet the specification for the old style binder pitches. For the American tars with high concentration of QI. no heat treatment is necessary.

(3:00 p.m.) A THEORETICAL ELABORATION AND AN INVESTIGATION OF POSSIBILITIES FOR INCREASING QUALITY OF THE COKE FOR PRODUCTION OF THE ANODL MATERIALS AT THE THERMAL TREATMENT STAGE: E. A. Kolodin, V. G. Viskllev J and G. F. Vedernikov. VAMI Institute, Stredmye Prospect

86, 199026, Leningrad, USSR. Porous structure surface properties of coke and content of heteroatoms maily depend on coke roasting process. Two conflicting processes take place simultaneously when roasting green coke - evolution of volatiles with coke expansion and shrinking due to restructuring carbon material. Roasting at upheat rate of 10 to 15 times lower than typical process allows reduction in roasting temperature by 100 to 150°C. Roasting in atmosphere of coke's own hydrocarbon volatiles and their pyrolysis on surface of roasted material improve performance figures of the process and coke quality.

(3;30 p.m.) INFLUENCE OF COKE CALCINING PARAMETERS ON PETROLEUM COKE OUALITY. W. K. Fischer. R. Perruchoud. Swiss Aluminium Ltd •• R&D Carbon. 3965 Chippis. Switzerland All physical and chemical properties of petroleum coke are determined by three basic parameters: - purity - structure - porosity. Structure and porosity are decisively influenced by calcining. The correlations between the calcining temperature, the throughput. the residence time and the coke properties are described.

TMS-AIME Annual Meeting Program - 21 (4:00 p.m.) TECHNOLOGICAL ASPECTS OF REINTRODUCTION OF COAL TAR IMPREGNATING PITCH IN THE NORTH AMERICAN ELECTRODE INDUSTRY: H. A. Kremer, S. Cukier, Domtar Chemicals Group, 1136 Matheson ~lvd., Mississauga, Ontario, L4W 2V4, Canada. Coal tar impregnating pitch was wid ley used in the North American electrode industry until the late seventies but due to quality detnands, its usage was very sigificantly reduced. An assessment was made of the requirements for an improved product. As a result of OUr program a high quality impregnating pitch was developed. The new pitch was evaluated against alternative products used by the industry and the results are presented (in this paper).

(4:30 p.m.) DIFFERENTIAL SCANNING CALORIMETRY OF PITCHES : J. L. Saint-Romain and P. Couderc ; Huiles, Goudrons et Derives, B. P. 189, 62304 Lens Cedex, France. Prebaked anodes used for electrolysis of alumina are prepared by mixing petroleum coke as a filler and coal tar pitch as a binder. It can be interesting for this application to hav~ a better idea of the thermodynamic and theological properties of the binder and therefore of its mole~ular weight spectrum. Differential scanning calorimetry studies of several coal tar pitches were carried out in order to test the ability of this method to provide new informations about their molecular weight distribution. The rheological behaviours of these materials were evaluated by measuring the ability of a fluid pitch droplet to flow into a granular coke bed. The results obtained clearly indicate that the D.S.C. data (glass transition temperatures, relaxation enthalpy) can be successfully used to compare several pitches of similar properties and to explain the abnormal flow behaviour observed for a few pitches.

DEFORMATION II TMS-AIME General Abstract Session Monday, February 25, 1985 2:00 p.m.

Colonial Room Sheraton City Squire

Session Chairman: R. J. Arsenault, Metallurgical Materials Laboratory, Chemical Engineering Building, University of Maryland, College Park, MD 20742

exponent (n) show a sharp drop with a very small amount of cold work (~5 - 10%). Electrical resistivity was used for measuring the degree of supersaturation. The two alloys are compared with respect to their structure and the tendency of the major alloying element to come out of solid solution. The results are also compared to similar tests on 99.99% purity aluminum. The effect of homogenization was also studied. (3:00 p.m.) BEND DUCTILITY OF 70-30 ALPHA BRASS C.J. Yang, H. Margolin, C.

D'Antonio and S. Nourbakhsh, Polytechnic Institute of New York, Brooklyn, New York 11201 When cold rolled, copper base alloys develop a distinct difference in ductility when the bend axis is perpendicular (good way) and parallel (bad way) to the rolling direction. The difference increases with increasing amounts of cold rolling. However, if the cold rolled material is partially recrystallized, and rerolled to establish the original hardness, marked improvement in the bend ductility is obtained. Failure during bending occurs by void formation at the boundary between shear bands and matrix. Fewer more intense shear bands occur in the as-rolled than in the plastically recrystallized, rerolled material. Shear bands in the as-rolled material tend to be straight I whereas in the partially recrystallized, rerolled material tlie shear band cracks tend to wander. It is proposed that the increased number of shear bands I the resulting less intense deformation and the i::endency for crack wandering contribute to the improved bend ductility of the partially recrystall·ized, rerolled material. This work was partially sponsored by NSF under grant #83 12963

(3:20 p.m.) DEFORMATION STUDIES ON Cu-10Ni-6Sn SPINODAL ALLOY: * Tonq C. Lee, S. Shekhar and K. N. Subramanian, Department of Metallurgy, Mechanics and Matenals SClence, Michigan State University, EAST LANSING, Michigan 48824-1226. Recent results based on a continuing investigation on the role of spinodal decomposition on mechanical behavior of Cu-10Ni-6Sn will be presented. In-situ studies in HVEM, and conventional TEM of defonned specimens provide a comprehensive picture of deformation structure in this alloy. The observed dislocation behavior is correlated with existing theoretical models.

* Research

supported by U. S. Department of Energy under Grant Number DE-FG02-B4ER45060. HVEM studies were carried out using the facilities at Argonne National Laboratories.

(2 :00 p.m.) STRESS CORROSION FAILURE ANALYSIS OF STAINLESS STEEL: R. Yazici, Stevens Ins t. of Tech., Dept. of Mats. & Met. Engg., Hoboken, NJ The defonnation induced by stress corrosion in 304 stainless steel (Fe-1Bcr-BNi) was studied by a method based on X-ray double-crystal diffractometry. Dislocation density in the indi vi dua 1 grai ns was monitored and mi cros truc tura 1 characteristics of the deformation process were detennined. Selective gra i ns a t the surface 1ayers showed a pronounced suscepti bil ity to stress corrosion, and as a whole the surface layers were preferentially work hardened compared to the bulk material. In parallel to the microstrain measurements, Auger-electron spectroscopy analysis revealed an enrichment of chromium and nickel and the presence of oxygen and chlorine elements in the surface films. The roode of progress ive bui It-up of di s 1oca ti on dens i ty observed in the alloys 1ed to a capabil i ty for predi c ti ng the stress corrosion 1 ife and failure by non-destructive means. (2:20 p.m.) EFFECT OF TEMPERATURE. STRAIN AND STRAIN RATE ON THE TENSILE FLOW STRESS OF ARMCO I.F. STEEL SHEET: M. R. Lin and R. H. Wagoner. Dept. of Metallurgical Engineering, The Ohio State University. 116 West 19th Avenue, Columbus. Ohio 43210 A series 1 of isothe~a1 tensile tests at strain rates varying from 10- /s to 10- /s were carried out over the temperature range o·c-ao·c in a stirred water bath. At each temperature. both the continuous rate sensitivity and the instantaneous rate sensitivity were measured. The tensile deformation characteristics of Armco I.F. steel were found to show a strong dependence on temperature and strain rate. An approximate constituti ve equati on was proposed which incorporates temperature. strain and strain rate effects. This equation is suitable for modelling deformation behavior during metal forming.

(3:40 p.m.) EXPERIMENTAL PROOF OF SURFACE AND INTERIOR STRESSES IN FATIGUED SINGLE CRYSTAL ALPHA BRASS, Z.R. Wang and H. Margolin, Polytechnic Institute of N.Y .• Brooklyn, N.Y.

11201

Single crystal 70-30 brass has been tested in tension-compression fatigue at rm. temp. The BSllschinger stress. the .05% offset stress in reverse flow, was found to decrease monotonically J with increasing number of cycles. When 0.25 nun is electrolytically removed from the surface the peak stress decreases, the hysteresis loop becomes wider and the Bauschinger stre!3s increases. This behavior is characteristic of a hard surface layer. It is proposed that the surface layer consists of two high dislocation regions between which is a softer low dislocation density area. The volume fractions are assumed to be such that the surface is softer than the interior. The high dislocation regions serve as obstacles to dislocation motion to the surface. Residual stresses develOp as a result of differences in surface and interior flow stress. Removal of material from one side of the specimen produces bending in accord wi th the assumptions. This research is sponsored by National Science Foundation under

Grimt 1183 12963

(4:00 p.m.) DEFORMATION AND RESIDUAL STRESS DISTRIBUTIONS IN SHOTPEENED 60-40 BRASS. I. C. Noyan and J. B. Cohen, Northwestern

University, Materi~ls Science and Engineering, Evanston, IL 60201 Recently we have demonstrated that it is possible to separate the macro and pseudo-macro residual stress components in plastically

a

surface deformed two-phase alloy by using X-ray diffraction tech-

niques.

In this paper this technique is used to determine the stress

states existing in both phases of a shot-peened 60-40 brass speci-

men.

It is seen that while in the matrix (Cl-phase) the pseudo-macro

stress component is negligible, in the precipitates (a-phase) both the

(2:40 p.m.) A STUDY OF THE VARIATION OF UNIFORM ELONGATION WITH COLD WORK IN A1-Mn and A1-Mg ALLOYS: Hemant Nani vadekar and J. G. Morri s, Department of Metallurgical Engineering, University of Kentucky, Lexi ngton. KY 40506.

macro and the pseudo-macro stress components are significant. These results, coupled with line-broadening studies} are used to develop a new model for the formation of residual stresses in shotpeened soft materials.

In contrast to previous models based on

Hertzian pressure, this new model yields the correct plastic deforrn~tion distribution in addition to the correct residual stress distribution with depth.

The drop in uniform elongation with cold work is examined for D.C. cast 3003 and 5005 aluminum alloys. Tensile tests were carried out on the two alloys with variable amounts of cold rolling. It was observed that the uniform elongation and the strain hardening

I hiS research was funded by ONR.

22 - TMS-AIME Annual Meeting Program (4: 20 p.m.) " PRELHIINARY STUDY OF GRAIN BOUNDARY DISLOCATION STUCTURES IN " S"C\'LRPLASTICALl.Y DEFORNElJ DUPLEX STAINLESS STEEL:

C.L. Dunlop+, and P.R. Howell~~. t;Department of and Engineering, Penn State Vniv., University of Physics Chalmer Univ. of Tech. Gothenburg

trial), refinery bleed-off solution and refinery electrolyte. Equipment designs were developed for the series as well as the parallel mode of electrorefining, the former yielding th~ lowest specific energy consumption. For large potential applications of gas-agitation/close-spacing, the inherent advantage in terms of low specific energy consumption in relation to production could be augmented by the capability of adapting to time-of-day utility rates.

i r h.-l=' beL'n recognized for many years that grain boundary sliding (I,BS) is the major ~train providing mechanism during super-

plastic. flow. However. results concerning the structure of grain b, und,elr ies, and in particular the grain boundary dislocation II dU) structures, in superplastically deformed material have only r·eported for a "single phase" copper alloy. In the present riVt'stigation, a two phase duplex stainless steel has been exiIlt.:.,d using lransmission electron microscopy. The material was Jl'turmeo at 950°C at strain rates in the range of 10- 5 _10- 2 s-l ~:IlJ CED distribution characterized in terms of pile-ups at ~ riple junction and second phase particles. Similarly, the distribution of interphase interface dislocations (lIDS) have been Finally, sources of GED s and lIDS have been docu-

(4:40 p.m.) INFLUENCE OF HIGH STRAIN ON THE SUBSTRUCTURE OF ALUMINUM, H.J.McQLJeen*, O. Knustad, fl. Ryum and J.K. Solberg. Phys. Met. Ins1:.-, Norwegian Inst. Technology, N 7034 Trondheim-NTH, Norway. Torsional deformation at 400"C and 0.2s- 1 was conducted on Al with 0.1 and 2mm grains to equivalent strains of 1,3,10,20,40 and 60. The grain and subgrain structures were examined by polarized light microscopy and TEM on tangential sections. The initially equiaxed surface grains wound into spirals so that their axial spacing varied inversely as the strain. Equiaxed subgrains of 7~m persisted throughout straining from 1 to 60, causing the grain boundaries to become strongly serrated. The 0.1 or 2mm grains lost their distinctness at about 20 or 60 as they b~came as thin as subgrains. A preferred orientation developed with <110> parallel to a tangent and <111> and <110> parallel to the axis, but becoming <112> at high E. The microstructure of crystallites with mixed low and high misorientations results from subgrain formation, boundary migration into serrations. severe reduction in grain dimension, and grain rotation into a common orientation. With no long range migration of grain boundaries,or continued growth of subgrain misorientation, this is not ordinary discontinuous,or continuous, dynamic recrystallization.(*Mech. Eng., Concordia Univ., Montreal H3G lM8).

(5:00 p.m.) HOT WORKING AND STATIC RECRYSTALLIZATION OF Al AND Al-Mg-ALLOYS. H.J.McQueen* and N.Ryum, Physical Metallurgy Institute, Norges TeTiiTskeH¢gskole, 7034 Trondheim-NTH, Norway. -1 Torsion tests were carried out at strain rates of 0.41 and 0.82s on Al 99.997 and derived alloys of 0.50 and 0.94 Mg between 25 and 260"C. The flow curves attain a steady state regime which increased with Mg content and were much lower than for commercial alloys. The strain rate has a hyperbolic-sine stress-dependence and an Arrhenius type temperature-dependence with activiation energy close to tha t for self d i ffus i on, but i ncreas i ng with Mg content. Subgrain size was observed to increase with test temperature and to decrease with rising Mg content. The static recrystallization after hot working during holds at temperature (above 350°C) was observed by metallography and also by decrease in flow stress. Upon addition of Mg the rates of recrystallization decreased from that of Al, yet were much faster than commercial materials. The kinetics followed the normal Avrami equation with K values of 2.9 and 3.6. (*Mech. Eng., Concordia Univ., Montreal, H3G 1MB).

ENERGY REDUCTION TECHNIQUES IN METAL ELECTROCHEMICAL PROCESSES II Sponsored by TMS-AIME Electrolytic Processes Committee Monday, February 25, 1985 2:00 p.m.

Versailles Ballroom Sheraton Centre

Session Chairmen: Thomas W. Chapman, Chemical Engineering Department, University of Wisconsin-Madison, Madison, WI 53706; Glenn M. Cook, Chemical Technology Division, Argonne National Laboratory, Argonne, IL 60439

(2:30 p.m.) FERROUS/FERRIC DEPOLARIZATION IN COPPER ELECTROWINNING - MASSTRANSPORT AND CURRENT EFFICIENCY CONSIDERATIONS: A.V. Cooke, Martin Marietta Laboratories, Balto., MD,; J.P. Chilton and D.J. Fray, University of Caf'lbridge, England With increaSingly stringent regulations on S02 emissions, hydrometallurgical alternatives to copper smelting are becoming more attractive. These processes are 1 imited economically by the energy intensive electrowinning step, ann can only become competitive if the cell voltage is reduced significantly. This is possihle with modified solution chemistry and cell nesign, but may be achieved in existing tank-houses using alternative anodic react ions to the evol ut ion of oxygen. Because the ferrous/ferric reaction occurs at lower standard electrode potential and reduced overpotential, the cell voltage is approximately lV lower. To use this reaction catalytic anodes are required, and forced convection is needed to exploit the low concentrations of ferrous ion present in conventional electrolyte. This paper presents a technique for assessing mass-transfer conditions. Current efficiencies were al so measured with progressive increase in ferric ion concentrat ion.

(3:00 p.m.) Break

(3:30 p.m.) MASS TRANSFER STUDY IN A FBE: Y.C. Hoh and M. S. Chia, Institute of Nuclear Energy Research, CABC, P.O. Box 3-7, Lung-Tan, Taiwan, R.O.C.

t-'..ass transfer coefficients for a conventional, resin and glass particles fluidized bed electrowinning were studied. The experimental results indicated that the higher the electrolyte flow rate, the high the limiting current and mass transfer coefficient are resulted. From the mass transfer point of view, the glass particle fluidized bed gives the best results, the resin particle fluidized bed is better than the conventional cell. Based on the experimental data, the dimensionless group jD-factors are correlated for conventional cell, resin particle FBE and glass particle FBE. Furthermore, the electrodeposition rate, power consumption and current efficiency are also reported.

(4:00 p.m.) FLUIDIZED BW ELECTRODEPOSITION OF CHROMIUM FROM DILUTE SOLU-

TIONS: Greg W. Gettinger, DepL of Chemical Engineering, Iowa State University, Ames, IA 50011, and Renato Ga Bautista, Dept. of Chemical & Metallurgical Engra, University of Nevada Reno, Reno, NV 89557. The recovery of hexavalent chromium from very dilute solutions in a fluidized bed electrochemical reactor is under study. The electrolytes that are being employed are solutions of chromic acid, sulfuric. acid and ferrous sulfate. The anolyte and catholyte are recirculated through separate reservoirs and the anode and cathode cells are physically separated by a sufficiently nonporous Vycor glass diaphragm. The current efficiency, power consumption rate and the deposition rate in the FBER were determined for a variety of operating conditions. The chromic acid concentrations in the catholyte were varied from 1-50 gm/liter. In all the catholytes used, the initial chromic acid/sulfuric acid ratio were 100/1. The partic~late electrode consisted of a 50 gram bed' of chromium particles of sizes ranging from 500-800 \lma

(4:30 p.m.) COMPUTER CONTROL OF METAL ELECTROREDUCTION CELLS:

(2 :00 p.m.) UPDATE OF GAS-AGITATION/CLOSE-SPACING IN ELECTROLYTIC l'IETAL PRODUCTION, WITH EMPHASIS ON ENERGY INTENSITY: W. W. Harvey,

4 Old Colony Lane, Arlington, MA 02174, Paul Ra Ammann, King George Drive, Boxford, MA 01921. Gas-agitation technology, as developed in the 1970's at Kennecott/Ledgemont, emphasized close face-to-face separation of electrodes in order to (a) reduce electrical energy consumption and (b) further improve mass transport. The general technology, with appropriate modifications t was applied to the major copper-bearing aqueous streams of the primary copper industry: waste-dump and vat-leach solutions, solvent extraction electrolyte (including a not previously published field

R. P. Singh,

J. H. Flint, and D. R. SadowaYt Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 8-109, Cambridge, MA 02139. Electrolytic metal reduction operations in aqueous and molten salt electrolytes have been studied previously by digital signal- analysis. The fast Fourier tranform of cell voltage (in galvanostatic operations) or cell current (in potentiostatic operations) is computed on-line in real time. The electrodeposition of manganese from molten MnCl2-alkali chloride electrolytes is being tested with respect to computer control of the deposition process. Electrowinning and electrorefining are being investigated as models for molten salt electrolysis operations. This work is supported by NSF under Contract CPE-Bl1664l.

TMS-AIME Annual Meeting Program - 23 ENVIRONMENTAL CONTROL II Sponsored by the TMS Light Metals Committee Monday, February 25, 1985 2:00 p.m.

Imperial Ballroom A Sheraton Centre

Session Chairmen: V. L. Bullough, Reynolds Metals Company, Carbon Products Division, Baton Rouge, LA 70809; Seymour Epstein, The Aluminum Association, 818 Connecticut Ave., Washington, D.C. (2:00 p.m.) UPDATE OF ALUMINUM ASSOCIATION STUDIES OF FLUIDIZED BED COMBUSTION OF SPENT CATHODES: Seymour Epstein, The Aluminum Association. (2:30 p.m.)

(2:25p.m.) IRON-NITROGEN AND MANGANESE-NITROGEN SYSTEMS: N. A. Gokcen, R. H. Nafziger, Albany Research Center, Bureau of Mines, U.S. Dept. of the Interior, Albany, OR 97321, and H. A. Wriedt, 148 Washington Street, Pittsburgh, PA 15218 Phase equilibria in iron-nitrogen and manganese-nitrogen systems are critically evaluated and the binary condensed-phase equilibrium diagrams are presented. The solubilities of nitrogen in solid and liquid terminal phases are obtained as functions of temperature and nitrogen gas-pressure in terms of the standard Gibbs energy change for 0.5N2 (g) + IN], where IN] is the atom fraction of dissolved nitrogen. -

(2:50 p.m.) PHASE DIAGRAMS AND CRYSTAL STRUCTURES IN THE TERNARY SYSTEMS TltANSITION METAL-ALUMINUM-NITROGEN

UPDATE OF MARTIN MARIETTA PYROSULFOLYSIS PROCESS FOR TREATING SPENT CATHODES.

J.e.

Schuster (University of Vienna, Vienna, Austria),

J. Bauer (INSA Rennes, France), H. Nowotny (University of

Connecticut, Storrs, CT)

(3:00 p.m.) UPDATE OF PYROHYDROLYSIS PROCESS FOR TREATING SPENT CATHODES. (3:30 p.m.) UPDATE OF THE USE OF SPENT CATHODES IN CEMENT KILN APPLICATIONS. (4:00 p.m.) A PROFITABLE & ENVIROMENTALLY ACCEPTABLE PROCESS FOR THE DESTRUCTION OF SPENT POTLINING & THE SUBSEQUENT PRODUCTION OF .AIF3 , CAUSTIC AND GRAPHITE: J. F. Bush, Aluminum Company of America, ALCOA Center, PA 15069

(4:30 p.m.) FUNDAMENTAL STUDIES OF PYROSULFOLYS'IS REACTIONS: Alvin F. Bopp and J.M. Brupbacher, Martin Marietta Laboratories, 1450 Rolling Road, Baltimore, MD 21227

s.

Pyrosulfolysis provides a means for destroying cyanide and recovering fluoride and energy from spent potlining. Initial pilot tests showed that the addition of steam and S02 does not hamper combustion stability and fluoride can be captured downstream. Laboratory runs were carried out in a bench-top reactor and a thermogravimetric analyzer (TGA). The data from the TGA experiments were used to generate a kinet ic rate 1aw which was appl ied to the bench top data. Despite scatter, there is agreement between the the two techniques. Using NaF as a model salt, the rate law can be written

-4£-

= k [S02]1. [H 20]·5 [0 2]0.

where Ea = 13.6 kcal /mol e. A 1aboratory-scal e fl uid-bed combustor has been constructed to test further the process chemistry. The results of these experiments are discussed.

G. R. FITTERER SYMPOSIUM ON NITROGEN IN METALS AND ALLOYS II Sponsored by the ASM-MSD Thermodynamic Activity Committee Monday, February 25, 1985 2:00 p.m.

(3:20 p.m.) KINETICS OF NITROGEN ABSORPTION AND DESORPTION BY LIQUID IRON AND IRON ALLOYS: T. P. Battle and R. D. Pehlke, Department of Materials and Metallurgical Engineering, The University of Michigan, Ann Arbor, MI 48109

ABSTRACT NOT AVAILABLE

~

Knowledge of the constitution of ternary TME-Al-N systems is of relevance for the evaluation of potential applications in high temperature ceramics and fusion reactor technology as well. The occurrence and crystal structure of te:cnary compounds is furthermore of interest for applications as abrasives and considerations in structure chemistl:Y. The ternary systems of aluminum and nitrogen with Sc,Ti,V ,Cr ,Mn,Fe,Co,Ni, Y ,Zr ,Nb,Mo,Ru,Rh,Pd,La,Ce, pr,Nd,Sm,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Bf,Ta,W and Re were investigated experimentally and the existing literature critically evaluated. An overview of the occurring phase equilibria and characterization of ternary crystal structures is presented.

Consulate Suite Sheraton Centre

Session Chairmen: J. F. Smith, Iowa State University, Ames, IA 50011; S. Ban-Ya, Department of Metallurgy, Tohoku University, Sendai, Japan 980 (2:00 p.m.) TIlE EFFECT OF TITANIUM ON TIlE NITitOGEN SOLUBILITY IN A COMPLEX LIQUID Fe-Cr-Ni Alloy: D. S. Shahapurkar, Cabot-Berylco Corporation, Reading, PA 15601, and M. Small, Pennsylvania State UniverSity, University Park, PA 16802 The influence of dilute additions of titanium on the so.lubility of nitrogen in the ternary alloy I (21%Cr, 33%Ni, 46%Fe) was studied over the range of 1450 - 1600· C. Experiments were performed with the titanium level in this alloy increased up to about 0.20 wt%. A similar study was conducted for a Fe-Cr-Ni alloy close to I. In both cases, it was found that Sleverts' Law for atomic nitrogen dissolution followed up to a pressure of nitrogen below 1 atmosphere I where a separate nitride phase was "fo-rmed. From x-ray analysis. this compound is believed to be essentially titanium nitride. Values for important thermochemical parameters have been derived for the effects of titanium on nitrogen solubility and nitride formation. It was observed. contrary to the results of other studies, that titanilDD tends to lower the solubility of nitrogen in both alloys of t his series. An analysis of this behavior is presented.

A summary presentation is made of rate measurement and kinetic analyses for absorption and desorption of nitrogen gas in liquid iron and iron alloys. Experimental techniques are compared and an error analysis is developed for measurement limitations. Kinetic models for absorption and desorption are critically assessed.

(3:50 P.M.) Break (4:00 p.m.) The Kinetics of Nitrogen Reaction with Liquid Iron and Iron Alloys P. C. Glaws and R. J. Fruehan, Dept. of Metallurgical Engineering and Materials Science, Carnegie-Mellon university, Pittsburgh,PA The rate of the interfacial reaction of nitrogen gas with liquid iron and iron containing Cr, C and 5 has been measured using the isotope exchange technique. The results are compared with nitrogen absorption rates as determined by conventional modified Sieverts experiments performed on the same experimental apparatus. The agreement between the rates derived from the two techniques under conditions of a chemical reaction controlled rate in the modified Sieverts technique, provides strong evidence of the dissociation of N2 on the surface as being the rate limiting step in the intrinsic chemical reaction mechanism. Results from the isotope exchange experiments on Fe-Cr alloys will be discussed, wi th the emphasis on the effect of Cr on the reaction mechanism.

(4:25 p.m.) RATE OF NITROGEN DESORPTION FROM LIQUID IRON AND IRON-CHROMIUM ALLOYS: S. Ban-Ya, F. Ishii, and Y. Iguchi, Department of Metallurgy, Tohoku University, Sendai, Japan, 980 The rate of nitrogen desorption from liquid iron and iron-chromium alloys was measured by using argon as carrier gas at 1600 0 C. The argon used was purified by passing through liquid calcium. The oxygen contents of pure iron were kept at about 30 to 40 ppm. The rate of nitrogen desorption from liquid iron was found to be second-order with an activation energy of 34 kcal/mol. The reaction rate in liquid iron-chromium alloys was also second-order for nitrogen content in metal. The rate of nitrogen desorption decreases with increasing chromium content. The effect of chromium on the rate was explained by the activity coefficient of nitrogen.

(4:45 p .... ) PANEL DISCUSSION BY AUTHORS. (5:00 p.,..) CLOSING Rf:)!ARKS:

Y. A. Chang, Department of Metallur-

lical and iUneral Engineering, University of Wisconsin, Madison, WI 53706; S. C. Singhal, Westinghouse R. & D Center, Pittsburgh, PA 15235; and N. A. Gokcen, Albany Research Center, Bureau of M1ne., U.S. Department of the Interior, Albany, OR. 97321.

24 - TMS-AIME Annual Meeting Program GENERAL PYROMETALLURGY II Sponsored by the TMS Pyrometallurgy Committee Monday, February 25, 1985 2:00 p.m.

Province Room Sheraton Centre

(3:40 p.m.) VACUUM R~INING OF COPPER ALLOY SCRAP, J. Krueger, Institut Fuer Metallheuttenwesen und E:l.ectrometallurgie der Rwth Aachen, Intzestr 3, D-5100 Aachen, \,est Germany

Srssion Chairmen: H. R. Traulsen, Lurgi GmbH, Gervinusstrase 17/19, D· E000 Frankfurt, West Germany; K. L. Bailey, Kennecott Process Tc·chnology, 1515 Mineral Square, Salt Lake City, UT 84112

No Abstract Available

(4:05 p.m.) SMELTING PROCESS UPDATE AT FALCONBRIDGE LIMITED SUDBURY OPERATIONS, R. R. Hoffman and G. H. Kaiura, Falconbridge Ltd., Sudbury Operations, Falconbridge, Ontario, canada

(2.l0 p.m.) BEHt,VIOUR OF MINOR ELEMENTS IN ONAHAMA SMELTER : H. Kohno, H. Asao, T. Igarashi, T. Shimizu, Onahama Smelting & Ref· ntng Co., Ltd., 1-1, Nagisa, Onahama, Iwaki-City, FukushimaPrj: "ecture, Japan

Imp!lri ties such as As, Bi, Sb etc, in copper concentrate are inc·~easing gradually and it becomes important to understand the behaviour of them in the copper smelting process. At Onahama Sme .ter, the dust from boilers, electrostatic precipitators of the reverberatory furnaces, and from the boilers of the CO:1"erters is ordinarily treated during the slag making stage of COtl"erter practice. Recently the tests for studying in more detail the behaviour of minor elements in smelting and converting proeess were preformed with recycling all kinds of dust into revnrberatory and converter furnaces. This paper presents the SOinf! information on the behaviour of impurities in practical opeJ'ation and results of our tests.

A new smelting process was started up in 197B at the Falconbridge Smelting complex to replace the previous sintering - blast furnace operati on. The new process consisted of a roasting-electric furnace operation to treat nickel copper sulphide concentrates from the milling operations. The installation included a sulphuric acid plant for the removal of sulphur dioxide from the roaster "off gas". The complex was designed to reduce sulphur emission to atmosphere, improve the working environment and improve productivity. This paper describes the major process improvements in metal losses, envi ronment impact and reI i abil ity. The status of current research and development investigations for further process efficiency is discussed as it relates to the major metals - nickel, copper and cobalt.

(2 :;!5 p.m.) CONCEPT OF A COMPUTER CONTROLLED COPPER REFINING PROCESS IN AN ROTARY F1JRNACE: G. Fleischer, kabelmetal Osnabruck; E. Custovic, Dr·. h.c.R.Kanunel, Technische Universitat Berlin; U.Lembke,Berliner Kt:pfer-Raffinerie Tr.e rotary furnace for copper refining with a capacity of 30 tons ar.d all facilities belonging to it are briefly discribed.Included ar:d specified are the data necessary for process control. There exist three categories of data measurements: l)data which can be measured continuously, for example the flow rates of fuel and combustion air as well as the off-gas temper a tUre . 2)da.ta which can only be measured periodically, for example the melt temperature and melt analysis. 3)da.ta which cannot be measured directly and therefore result out of calculation from 1.) or 2.), for example the mass of the slag. After having measured or calculated all data, the models for process optimization can be developed for each different process step, for example charging, melting, refining and tapping.The

~~~i~ ~~~~ge o~!tgfa t~~~dii~ri~~c~~f~o8f I~500b~0~~p~:~ny~a~: (2:~iO

a

p.m.)

DEVELOPMENT OF TOP BLOWN PEIRCE-SMITH CONVERTER PROCESS: Takayoshi Kimura, Seiichi Tsuyuguchi and Yutaka Ishii Niihama Metallurgical Research Laboratory, Sumitomo Metal Mining Co •. Ltd. 3-5-3, Nishibara-cho, Niihama city, Japan By 1lsing a 6 ton Peirce-Smith copper converter equipped with a top· blowing lance, pure oxygen or oxygen-enriched air is inj I!C ted through the top blowing lance, at the same time air is injl!cted through the conventional tuyers. The .high oxygenenriched copper converter operation was successful without severe refactory erosion at the tuyer line. The efficiency of the oxygen, the life of the lance, the distance between the tip of the lance and melt, spitting of the melt, and the melt adhering to the lance are discussed. Also cold dope was injected through the lance and it was observed that the amount of the carl'ing dust is very small compared with the conventional charging method. With this new method i t was very easy to contorol the liquid temperature.

(3:15 p.m.) EFFECT OF ANODE MILLING AT SAGANOSEKI SMELTER: T. i abe, K. Monzen, N. Oka, and K. Sakai , Saganoseki Smelter and Refinery, Nippon Mining Co. '. Ltd., Saganoseki, Ohitaken, Japan Sagenosek! Smelter and Refinery has applied own designed anode processing equipment which has the following three functions for improving a quality of the conventional anode. -

Pressing anodes to reform flatly Milling the bottom of lugs to make very smooth surface Rejecting substandard anodes in weight and thickness

Efficient results have been obtained from these. functions. -

Less power consumption due to decrease of contact resistance Less operators at tank house due to improvement of anodes verticality

(4:30 p.m.)

BEHAVIOUR OF SWIRLED LANCES IN SLAG MELTS 'A MODEL STUDY': M. Nilmani, University of Melbourne, Chem. Eng. Dept., Parkville V~ctor~a 3052, Melbourne, Australia; D. S. Conochie, Aberfoyle Ltd., Vlctorla 3000, Melbourne, Australia; J. M. Floyd, Ausmelt Pty. Ltd., P.O.Box 117, Upper Beaconsfield 3808, Victoria, Australia. Lances with swirlers have already been used successfully in non-ferrous smelting processes with the SIROSMELT system. In smelting and slag cleaning operations liquid baths have relatively high viscosities at the operating temperatures. In an attempt to model the gas dispersion in slag baths, gases have been injected in~o aqueous glycerol solutions through swirled lances. Use of sWlrlers has been found to provide improved gas dispersion in the liquid bath. .

HERBERT H. KELLOGG SYMPOSIUM: General I Sponsored by The Physical Chemistry Committee and The Copper, Nickel, Cobalt and Precious Metals Committee Monday, February 25, 1985 2:00 p.m.

Regency Ballroom Sheraton Centre

Session Chairmen: D. R. Fosnacht, Inland Steel Company, 3001 East Columbus Drive, East Chicago, Indiana 46312; S. Young, ARCO Metals Company, Tucson, AZ 85726 (2:00 p.m.) ELECTROCHEMICAL SENSORS FOR THE DETECTION OF SOa AND/OR S03: w. L. Worrell and Q. G. Liu, Department of Materials Science and Engineering, University of Permsylvania, Philadelphia, PA 19104. Solid-sulfate electrolyte cells have been recently developed to measure SOa and/or S03 in gases. After describing the principal guidelines used to develop these sensors, results with singlephase electrolyte cells are sunmarized. The single-phase electrolyte sensors with gas-reference electrodes are reliable, but voltage instabilities are observed with solid-reference electrodes. Because a solid reference offers distinct advantages, a novel two-phase electrolyte cell has been developed in our laboratory. This two-phase electrolyte sensor has exceptional reliability and long-term chemical stability.

(2:30 p.m.) EXTRACTION OF SILVER THROUGH COMPLEXATION IN TIlE VAPOR PHASE: J. P. Hager, Colorado School of Mines, Golden, Colorado; M. C. Rupert, Handy and Harmon, Fairfield, Connecticut; and W. A. May, AMAX Research, Ann Arbor, Michigan. The vapor pressure of silver chloride has been measured using a double-zone transpiration technique. Results are presented over a temperature range for which no measurements are presented in the literature. The enhanced volatility of silver chloride in the presence of iron chloride and potassium chloride, due to the formation of vapor complexes, has been measured. A several fold increase in silver chloride vapor pressure is possible under proper conditions. Gibbs free energies have been detet"Jllined for the vapor transport reactions. Laboratory kiln tests were also conducted to confirm the enhanced recovery of silver through the formation of vapor complex species.

TMS·AIME Annual Meeting Program. 25 (3:00 p.m.) CHLORINATION OF ALUMINA BY CO/C12 GAS MIXTURES*: Y.K. Rao and M.K. Soleiman, Metallurgical Engineering, FB-lO, University of Washington, Seattle, Washington 98195 The chlorination of alumina by gas mixtures containing CO and C12 has been investigated in the temperature range 750 to 950oC. The reaction kinetics have been determined by the thermogravimetric method. The effect of gas composition on the chlorination kinetics has been investigated. The results have been interpreted by means of a coupled surface reaction/mass transfer model. *Supported by the Office of Surface Mining, U.S. Department of the Interior, Washington, D.C. (3:30 p.m.) ECONOMIC CONSIDERATIONS IN MANAGEMENT OF R&D IN EXTRACTIVE METf,LLURGY: Dr. J. C. Agarwal, Amax Metal s Group, Two Greenwich Plaza, Greenwich, Connecticut Considerable amount of R&D is undertaken without regard to capital costs inherent in the extractive metallurgy plants. Elements of capital cost in various types of extractive metallurgy plants will be discussed. The second part will discuss the amount of R&D budqet a company should have in relationships to its ability to exploit the fruits of R&D.

kinetics of oxidation of iron in gas mixtures of argon, oxygen and chlorine at temperatures between 900 and 1200 K will be described and compared with the kinetics of oxidation of nickel and cobalt in similar envirorunents. This research is supported by the Department of Energy under Grant AC02 ER82 12093.

(2:20

~.m.)

VAPORIZATION OF ALLOYING ELEMENTS FROM STAINLESS STEEL MELTS·: P.A.A. Khan, M. Collur, A. Paul and T. DebRoy, Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pa.

Vaporization rates of various alloying elements from laser melted pools of USS Tenelon, AISI 201 and AISI 202 vari Ues of stainless steels are determined experimentally. The effects of variation of laser power and scanning speed are studied. During laser processing of alloys it is always a difficult task to determine the temperature of the molten pool since this region is surrounded by hot plasma. I t is demonstrated that the relative vaporization rates of various alloying elements can serve as an indicator of pool temperature. The composition of the laser irradiated material is determined by SIMS and EPMA. • Sponsored by the U.S. Department of Energy under grant # DEFG02-84ER45158

(4:00 p.m.) INTERFACIAL KINETICS IN THE DEOXIDATION OF LIQUID COPPER BY CO

(2:40 p.m.) G.R. Belton, BHP Central Research Laboratories, P.O. Box 188, Wallsend, 2287, NSW, Australia.

A.E. Lindemanis, Combustion Engineering Corp. Stamford, Connecticut, 06902.

The rate of deoxidation of liquid copper by CO at 1l00-1220°C has been studied by using a solid electrolyte cell to measure the oxygen concentration in an inductively stir,red melt under an impinging gas jet. At oxygen concentrations above about 0.01 wt pet and under conditions where mass transport does not influence the rate, the rate is a function of temperature and the pressure of CO only. It is deduced that the rate limiting step involves an Eley-Rideal mechanism in which CO, either as a gas or in a weakly adsorbed state, reacts with chemisorbed oxygen at near-full surface coverage. Rate equations are presented and previous studies are analyzed in the light of the findings of this work.

(4:30 p.m.) THE SIMULATION OF MELTING AND SOLIDIFICATION PROCESSES IN THE METAllURGICAL SCIENCES~A.D.Solomon, Oak Ridge Nat.lab.and A.S. Roy,Ben-Guri on Uni vers i ty of the Negev. In this paper we discuss the roles and methodologies available to us for simulating melting and solidification of metals. We discuss the solidification of pure materials and alloy systems, describing the key elements of modeling required. We describe the role of natural convection and some recent relevant research. Models of conti nuous casti ng processes are exam' ned and some results concerned with pulsed laser annealing are described. We close with a discussion of the utility of process simulation in industrial metallurgical settings.

*lhlS work was supported by the U.S. DOE Applied Mathematical Sciences Program

OBSERVATION OF IRON OXIDE REDUCTION BY CONTROLLED ATMOSPHERE ELECTRON MICROSCOPY: M-F. Rau, D. Rieck and J. W. Evan., Molecular and Materials Research Division, Lawrence Berkeley Laboratory and Department of Materials Science & Mineral Engineering, University of California, Berkeley, Berkeley, CA 94720

An environmental cell has been used wi thin a high voltage transmission electron microscope to examine the reduction of Fe 20 3 , Fe304 and FeO by hydrogen, 10SH 2 /90SAr, and carbon monoxide. The new phases formed have been identified by electron diffraction. Reduction by pure hydrogen appears to occur by topochemical reaction even on a microscale. At temperatures where FeO is thermodynamically unstable, its exposure to a reducing gas causes the formation of Fe304 even at temperatures where the rate of dissociation of FeO is t.oo slow to observe. Reduction rates were observed to be slower in carbon monox ide and in argon hydrogen mixtures than in pure hydrogen.

(3:00 p.m.) CATALYSIS OF THE BOUDOUA~D REACTION BY CYANIDES AND OXYCYANIDES OF SODIUM AND POTASSIUM: M. Alam and T. DebRoy, Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pa.

The cyanides and oxycyanides of sodium and potaSSium are formed during the operation of many metallurgical furnaces. The kinetics of Boudouard reaction with or without the addition of various alkali metal compounds to carbon are investigated in the temperature range 1173 to 1373K. The effects of partial pressures of CO and CO 2 and the nature and concentration of vaTious alkali metal compounds are examined.

* KINETICS I: FERROUS SYSTEMS Sponsored by the TMS Physical Chemistry Committee and the PTDlISS Monday, February 25, 1985 2:00 p.m.

Dominion B Sheraton Centre

Session Chairmen: J. F. Elliott, Dept. of Materials Science and Engr., Massachusetts lnst. of Technology, Cambridge, MA 02139; M. J. McNallan, Dept, of Civil Engr., Mechanics and Metallurgy, U. of Illinois at Chicago, P.O. Box 4348, Chicago, IL 60680

(2:00p.m.) THE EFFECT OF CHLORINE CONTAMINATION ON THE KINETICS OF OXIDATION OF IRON..AT TEMPERATIJRES BETWEEN 900 AND 1200 K: S. Y. Lee, M. J. McNallan, Department of Civil Engineering, Mechanics and Metallurgy, University of Illinois at Chicago, P.O. Box 4348, Chicago, IL 60680

The presence of chlorine during the oxidation of metals has been shown to dramatically affect the kinetics of the oxidation reactions. Chloride reaction products are volatile at high temperatures, and it is the presence of these volatile species which can affect the kinetics of fonnation of oxides. The

Sponsored by the American Iron and Steel Institute

(3:20 D.m.)

Break

(3:30 p.m.) FORMATION OF MAGNESIOFERRITE AND ITS EFFECT ON THE PROPERTIES OF IRON OXIDE PELLETS: V.S. Hegde and W-K. Lu, Department of Metallurgy and Materials Science, McMaster University, Hamilton, Ontario, Canada, LBS 4L7. In iron oxide pellets containing MgO, the formation of magnesioferrite solid solution (Mg,Fe)O.Fe203 during induration has been studied for different pellet compositions, induration temperatures and oxygen potential of the indurating atmosphere. The formation of magnesioferri te solid solution induces the reduction of Fe203 to Fe304 at high temperatures. The reverse reaction takes place during cooling. Continuous measurement of weight change is used to study the formation and decomposition of magnesioferri te solid solution. Tensile strength of specimens were measured after induration and compared, which showed the adverse effect of MgO on the strength of iron oxide pellets. The weakening mechanism is proposed to be the formation of Fe304 and/or spinel solid solution during induration.

26 - TMS-AIME Annual Meeting Program (3:50 p.m.) EFFECT OF IMPURITIES IN HIGH PURITY MATERIALS ON THE KINETICS OF CARBURIZATION AND DECARBURIZATION OF Guzman* and D.G.C. Robertson** *Department of Metallurgy arrl Materials Science, U.C. V. , Caracas,Venezuela.**Departrnent of Metallurgy and Materials Sc ience, Royal School of Mines, Lorn on ,Englam . T.IQUTD IRON: M.E.

rhe reactions of carburization and decarburization of iron droplets containing impurities in the ppm range WE're still ie:.l in atmcs pheres of CO/C02 d ilute:.l in C02 al oxygen potentials lower than the require:1 to form i ron oxides in the temperature range 1550 to 1650 °C and at total press ures of 40 and 65 atmcs pheres. The reactions were blocke:l or retarded by the formation of thin f Urns of oxid es . A two phas e s lag was id entif ie:i on the surface of the s pee imens, one very rich in Al,Mg,Ca and Si and the other one rich in Si and

Ti. (4: 10 o.m.) THE KINETICS AND MECHANISM(S) OF REDUCTION OF IRON OXIDE IN LIQUID SLAG BY CARBON IN IRON. K. Upadhya'" and 1.0. Sommerville,t

;"Department of CEMM, University of 111 inois at Chicago, Box 4348, Chicago, IL 60689 and tDepartment of Metallurgical Engineering, University of Toronto, Toronto, Canada. The reduction of iron oxide in di lute solution in CaO-A1203-Si02 slag by carbon in iron was investigated in a system which excluded graphite. The variables studied to elucidate the reaction mechanisms were iron oxide concentration in slag, carbon content of iron, sulfur content of iron, slag composition and ambient pressure. The results obtained are explained by postulating the existence of a gas fi 1m at the slag/metal interface. It is suggested that the rate controll ing step for iron oxide reduction by carbon under the present experimental conditions is a chemical reaction at the gas/metal 'interface. The rate constant for ]-2.5% FeO in slag and 2-4.3% carbon in iron at 1400°c as calculated from the present study is 3.0 x 10- 2 mol/min/cm 2 /atm. At higher values of iron oxide content in the slag, it is postulated that a chemical reaction at the gas/slag interface takes over as the rate I imiting step.

(4:30

p.m.)

KINETICS OF THE REACTION OF S10(g) WITH CARBON SATURATED IRON:.

excessive grain coarsening. Experiments on widely different steels demonstrate improvements in blunt-notch toughness and ductil e-britt1 e trans i t i on temperature associ ated wi th hi ghtemperature austenitizing treatments. * This work was supported by the Office of Naval Research, Contract No. N00014-81-K-0013. (2:30 p.m.) PRECIPITATION STRENGTHENING OF A MELT SPUN Fe-Ni AUSTENITIC STEEL BY TiB 2 • C.M. Michal, Dept. of Metallurgy and Materials Science,

Case Western Reserve University, Cleveland, Ohio 44106 and T.K. Glasgow and T. J. Moore, Processing Science Section, NASA Lewis Research Center, CLeveland, Ohio 44135 An Fe base alloy containing 33Ni, 2Al, 6Ti, 2B by wlo was cast as ribbon ,,-,40).Jm thick by ,,-,Smm wide using a dual "free-jet" variation of chillblock melt spinning against a Cu wheel. There was sufficient B and excess Ti present to form 'VlO via TiB 2 . Ribbon was annealed from 500-1200°c in vacuum. Microstructural variations were determined by combined optical, X-ray, EDAX, EELS and TEM analyses. Concurrently, mechanical properties were evaluated by hardness and tensile testing. Ground reduced-section, 12. 5mm gauge length tensile specimens were prepared with the aid of a jig fixture. The as cast austinite grain size was found to be 'V0.02-0.05).Jm, coarsening to "-'l.O).Jm after anneals between 900-l200°C. Below lOOO°C, Ni3Ti and TiB2 both precipitated. Above lOOO°C, TiE2 formed preferentially. As cast, the alloy had a room temperature UTS in excess of 2400 MPa with negligIble plastic ductility. After annealing at lOOO°C, the UTS at room temperature and 650°C were 1480 and 325 MPa, respectively, with significant plastic ductility.

(2:50 p.m.) MECHANICAL PROPERTIES OF RAPIDLY SOLIDIFIED TYPE 304 STAINLESS STEEL:* G. E. Korth and J. E. Flinn, Materials Science Division. EG&G Idaho, Inc .• Idaho Falls. ID 83415 Rapidly sol idified Type 304 stainless steel powder produced by the centrifugal atomization process was consolidated by either hot extrusion or shock compaction techniques. Tensile. creeprupture, and fatigue tests were performed on the extruded material after various preconditioning thermal treatments. Resulting mechanical properties were correlated with the changes in mi crostructure. Flow and fracture behavi or was compa red with conventionally prepared wrought material. Hardness and fracture mechanisms of the shock compacted material were examined.

B. Ozturk and R. J. Fruehan, Carnegie-Mellon University, Pittsburgh, PA. The reaction of SiO(g) with carbon saturated iron plays an important role in silicon transfer in the iron blast furnace. In the tuyere zone SiO(g) is generated from the reaction of coke with it's ash and the 5iO(g) reacts with carbon saturated iron droplets as they pass through the furnace. This reaction may also playa role as a gaseous intermediate reaction for the reduction of Si0 2 from slags by carbon dissolved in iron. The rate and controlling mechanism for SiO reaction with carbon dissolved in liquid iron was determined in the temperature range l823-1923K. A constant pressure of SiO(g) was generated by the reaction of CO with 5i0 2 ; the reaction of carbon with Si0 2 gave higher but decreasing pressures of SiO with time. The SiO(g) generated was then reacted with carbon saturated iron under conditions for which the gas phase mass transfer conditions are clearly defined. By a systematic variation of the appropriate variables it was demonstrated that the rate was controlled by gas phase transfer of SiO to the gas metal interface.

MECHANICAL BEHAVIOR OF RAPIDLY SOLIDI· FlED MATERIALS II: Iron and Nickel Alloys Sponsored by the TMS Mechanical Metallurgy Committee and the ASM-MSD Flow and Fracture Activity Monday, February 25, 1985 2:00 p.m.

Regency Foyer Sheraton Centre

Session Chairmen: Morris Cohen, Massachusetts Institute of Technology, Cambridge, MA 02139; Harry Lipsett, Air Force Materials Laboratory, Wright. Patterson Air Force Base, OH 45433

(2:00

p.m.)

STRUCTURE-PROPERTY RELATIONSHIPS IN RSP HIGH-STRENGTH STEELS:* J.B. Vander Sande, G.B. Olson, and M. Cohen, Massachusetts Institute of Techno logy, Cambri dge, MA 02139 Rapid solidification of ferritic, austenitic, and martensitic stee 1s vi a centri fuga 1 and inert gas a tomi zati on has been found to produce significant refinement of inclusion phases. The size, distribution, and thermal stability of these fine inclusions allow them to act as effective grain-boundary pinning particles in hot-conso 1i dated steels, account i ng for unusual res i stance to grain coarsening at high austenitizing temperatures. This allows for the improvement of sharp-crack fracture toughness by high austenitizing treatments without the reduction in blunt-notch toughness and tensile ductil ity whi ch may otherwi se accompany

*Research sponsored by the U. S. DOl Bureau of Mines (3: 10 p.m.) EFFECTS OF RAPID SOLIDIFICATION ON NICKEL ALLOY PROPERTIES: A REVIEW: A. F. Giamei, United Technologies Research Center, Silver Lane, East Hartford, CT 06108 Rapid solidification has been a subject of considerable interest for the past eight years. Academic, Industrial and Government research has been done on Ti, AI, Fe, Co and Ni alloys. The rapid solidification process leads to a substantial reduction in the amount or dimensions :of microsegregation and also reduces inclusion size and grain si~e. Metastable microstructures can be produced via Rapid Solidification Rate (RSR) rotary atomization or by melt spinning. Following particulate sizing, consolidation (Hot isostatic pressing or extrusion), warm working, directional recrystallization and heat treat~ ment, potentially useful high temperature properties can be derived for nickel base alloys. These will be discussed as they relate to alloy design, y/y' misfit, texture, anisotropy, etc.

(J :40 p.m.)

Break

(4:00 p.m.) IIBCHANICAL BI!IIAVIOi OF is Ni SUPI!IIALLOYS lI.i. 1&9tao.. .u S. C. Buna General Electric COilpany Corporate Relearch and Develo .. ent P.O. Box 8. Sch .... ct.dy, N." Yort 12309 Sch.a.ctady. N.... Yort 12345 lIaay studi .. h.ve b •• a porfona.d Oil is Ni ... torials relat.d to procellina. micro,ltructure. oh_iltry. and phale Itability. Muoh of the relearch "a. oarried out OD convention.l Iuperalloy compoIl tiolllproc .... d by as t.chlliqu... Addi tio ... l studi .. h.v. shOYIl that as procellinl can be uled to extend the achievable rani' of chemiltriel anc1 micro.tructure. beyonc1 the li.it. forced by ca.t or. "rousht procellin,. The b•• e of available literature concernillS tho .echlllicd behavior of is •• t.riall is .... ller. The intent of the pre.ent revie" il to detail the •• ch.nic.l behavior of luch DI.teri.11 .1 formed • • 1 "ell a. after con.olid.tion .nd/or thermal proce.linl. Paph.li. "ill be on atcaized powder, .e1t .PUD ribbon. low pres.ure pl •••• depo.itl and atcaization depolition Ni-ba.e .a teriall. Monotonic and cyclic re.ponse achieved "ill be dilcussed in tel'lll of potential perforaance. Thil c.n lerve a • • ba.il for future directionl of research.

TMS-AIME Annual Meeting Program - 27 (4:30 p.m.) IlBASURING lBE MECHANICAL PROPERTIES OF RAPIDLY SOLIDIFIED ALLOYS USING MELT SPUN RIBBON:' A.I. Tub. C.P. PII •• r. II:-M CbI"1 IIld s.C. BU81l8, General Electric Corporate Research and Development,

(3:00 p.m.) EFFECT OF MECHANICAL HISTORY AT 9ZZK ON THE SUBSTRUCTURE DEVELOPMENT IN ALLOY 800*, Wendell B. Jones, Sandia National Laboratories, Albuquerque, NM 87185

Schenectady, NY. Extensive use bas been made of mel t spinniua to study the microstructure and mechanical properties of alloys as processed by rapid lolidification. In this presentation, the validity of the tensile t •• t data will be discussed. It will be shown that the yield strelliths measured all mel t spun ribbon are highly reproducible. Furtller, the data agrees with that obtained on bulk 'specimens produced from plasma depoli tion and powder conso1148t10n. In contrast to the yield strength. the strain to failure and the ulti.ate te~.ile strength are hiShly seDli tive to the castinl conditions and specimen surface preparation. The strain to failure data can be used to rank the relative ductilities of the alloys but the measurements represent only minimum values for bulk speciIlenl. Example~ will be liven for several nickel-base superalloYI as well al for boron modified Ni 3 Al. • Work partially supported by the Office of Naval Research.

Samples of Alloy 800 hav~ been exposed at 9ZZK under four conditions: isothermal aging. creep loading. low cycle fatigue CLCF), and creepl fatigue with a hold period (C/F). Solution annealed material showed MZ3C6 precipitation in all cases, particularly as a nearly continuous grain boundary film. Intragranular carbide precipitation also occurred in all cases, butthe final morphology was history dependent. These carbides formed early and subgrain formation was not observed. Mill annealed material showed fewer changes with exposure to 9ZZK. No further precipitation occurred during isothermal aging while fine scale «0.05/lm) was observed after both creep and C/F testing. Well defined subgrains were produced only by LCF. The influence of these changes on creep deformation and cyclic hardening will be discussed. -This work supported by the U.S. Department of Energy under contract number DE-AC04-76DP00789 • (3:20 p.m.)

MECHANICAL PROPERTIES II TMS-AIME General Abstract Session Monday, February 25, 1985 2:00 p.m.

Monarch Sheraton Centre

Session Chairman: D. J. Michel, Carnegie-Mellon Univ., Pittsburgh, PA 15213

(2:00 p.m.) INFLUENCE OF HEAT TREATMENT ON MICROSTRUCTURE AND TENSILE PROPERTIES OF TI-6AL-4V-2Ni: C. G. Rhodes, Rockwell International Science Center, Thousand Oaks, Ca. Ti-6Al-4V-2Ni is a modification of Ti-6Al-4V developed by Wert and Paton* for superplastic forming applications. The modified alloy in the solution-treated condition exhibits superplastic behavior at l500F (816C) comparable to that possessed by conventional Ti-6Al-4V at 1700F (927C) without sacrificing room temperature tensile strength. The addition of nickel to titanium alloys can result in the formation of intermetallic compounds of titanium and nickel which are generally regarded as undesirable microstructural constituents because of ther detrimental influence on tensile ductility. This talk will describe the thermal conditions under which the compound Ti2Ni forms in Ti-6Al-4V-2Ni and its influence on room temperature tensile properties. The possible consequences of compound formation on superplastic forming applications will also be discussed. *J.A. Wert and N.E. Paton, Met. Trans., vol. 14A, 1983, 2535-44.

(2:20p.m.) EFFECT OF BETA HEAT-TREATMENT ON MICROSTRUCTURE AND FATIGUE CRACK PROPAGATION IN TI-6Al-4V: C. G. Rhodes, J. C. Chesnutt, and J. A. Wert, Rockwell International Science .center, Thousand Oaks, CA 91360 It has been shown in recent years that microstructural conditions of Ti-6Al-4V resulting from beta heat treatment or beta processing genera lly exhi bi t superi or fati gue crack propagati on res i stance compared to alpha/beta processed material. In the present study, three microstructural conditions were produced by heating above the beta transus temperature followed by various controlled cool ing and substransus heat threatment steps. Results of a thorough microstructural characterization and fatigue crack propagation behavior in laboratory air at R = 0.1 and 30 Hz will be presented. Fatigue crack propagation will be correlated with the mi crostructura 1 and fractographic data obta i ned. Sponsored by the Air Force Office of Scientific Research under Contract No. F49620-83-C-0055. (2:40 p.m.) FATIGUE CRACK GROWTH BEHAVIOR OF POWDER ALUMINUM ALLOY CW67: J. J. Kleek. F. H. Froes, Air Force Materials Laboratory, AFWAL!HLLS. Wright-Patterson AFB. OH 45433; and Young-Won Kim. Metcut-Materials Research Group, P. O. B1?x 33511, Wright-Patterson AFB. OH 45433

A second. generation high strength powder aluminum alloy CW67 developed by Alcoa has about a 30% improvement in yield strength along wi...th a 10% higher fracture toughness over conventional alloy 7975 in the T73 temper. The first generation powder alloy 7091 has also demonstrate~ improved properties over conventional ingot alloys except for FCC resistance which has shown to be inferior at low stress intensities under constant amplitude loading. However. under "Falstaff" spectrum loading co~ditions, the life of alloy 7091 is about 50% longer than ingot alloy 7050. In this study. both constant amplitude and spectrum loading FCG tests were conducted on alloy CW67. The FCG behavior will be correlated with the microstructure and compared to alloy 7050.

CREEP-FATIGUE BEHAVIOR OF STEAM-FILLED TUBULAR SPECIMENS OF ALLOY 800*, J. A. VanDenAvyle and Wendell B. Jones, Sandia National Laboratories, Albuquerque, NM 87185 Tubular specimens of Alloy 800 containing steam at a pressure of 15.2 MFa were cycled under axial strain control at 616K and 922K. Tubular specimen lives were similar for tests conducted in steam or air environments, showing little effect of internal pressure or steam environment. Lives were significantly less than solid bar tests conducted at equivalent strain ranges. Either tensile or compressive hold periods reduced cycles to failure at 922K. Fractography showed intergranular growth for tensile holds and transgranular growth for compressive holds. Crack initiation was greatly enhanced on inner tube surfaces for the compressive hold tests. Observed differences in fatigue lives are related to effects on crack initiation and propagation.

*This work performed at Sandia National Laboratories supported by the U.S. Department of Energy, Contract No. DE-AC04-7DP00789.

(3:40 p.m.) EVALUATION OF THE EFFECT OF CRACK CLOSURE ON FATIGUE CRACK GROWTH OF SIMULATED SHORT CRACKS: Jack Telesman and Douglas M. Fisher, NASA Lewis Research Center,eTeveTiiiia:-OR 44135 A test program was performed to determine the infl uence of crack closure on fatigue crack growth of short cracks. By the use of the standard compact tension specimen, test procedures were devised to evaluate closure loads in the wake of the crack behind its tip. The first procedure determined the magnitude of crack closure as a function of the fatigued crack wake by incrementally removing the contacting wake surfaces and measuring closure load at each increment. The second procedure used a low-high loading sequence to simulate short crack behavior. The results will be discussed in terms of the applicabilty of crack closure phenomena to explain short crack growth behavi or. (4:00 p.m.) DUCTILITY AND FRACTURE BEHAVIOR OF Ni -Cr-Ce ALLOYS: J. Kandra and F. CQsandey, Department of Mechanics and Materials Science, Rutgers University, P.O. Box 909, Piscataway, NJ 08854 Tensile tests as a function of temperature and .strain rate ranging from 4.6xlO- 5 to 4.6xlO- 2 9- 1 were performed on an 80 Ni-20 Cr alloy with Ce additions of 0, 66 and 180 at. ppm. It is observed that Ce has little effect on yield" point t work hardening behavior and saturation stresses. The maximum effects caused by Ce are observed for alloy ductilities. At the highest strain-rates, the strains to fracture converge toward a similar value for all alloys. However, ~t the lowest strain rate t fracture strain ranging from 0.30 for the alloy without Ce to 0.83 for the 180 Ce containing alloy are observed. These strain variations are accompanied by transitions in fracture modes from transgranular to intergranular. The role of Ce or fracture behavior will be discussed. Particular attention will be given for temperature, strain rate and alloying ~ffect8 on grain boundary sliding t fracture and deformation processes.

(4:20 p.m.) THE IMPACT TOUGHNESS AND FATIGUE STRENGTH OF AUSTEMPERED AISI 5150 ANO AISI 1060: D. L. Turner, Fisher-Barton, Inc., Watertown, WI, J. S. Salerno, IBM, Rochester. MN and F. J. Worzala, University of WiSCOnSin, Madison, WI The impact toughness and fatigue strength of AISI 5150 and 1060 in the austempered and quenched and tempered conditions have been investigated. A higher impact toughness was observed after austempering to high hardness levels. At low hardness levels, the

28 - TMS-AIME Annual Meeting Program yuenched and tempered structure was tougher. At hi gh hardness, intergranular embrittlement occurred on tempering. The au,tempered structures were not subject to the same embrittlement. The fatigue tests were c"rried out at intermediate hardness levels. The endurance limit of the quenched and tempered structure was slightly higher. At the same time, superior lowThe cyel e fat i gue res i stance was achi eved by a"stemperi ng. results were rationalized in terms of carbide morphology, packet size and internal stresses. (4:40 p.m.)

accomplished through the design and fabrication of several demonstration articles, including a F-l8A vertica] stabilizer actuator panel and the T-38 main landing gear door. The concept used to produce the SPF/DB sandwich structures combines into a one-step operation. the diffusion bonding of two core sheets, the superplastic forming of the two face sheets, and the diffusion bonding of the core sheets to the face sheets. The paper will analyze the bonding integrity and core configuration verification by ultrasonic and radiographic evaluation. Finally, weight and cost of the SPF/DB technique will be compared to the conventional methods of producing titanium and aluminum structures. *This work was supported by Northrop ManTech Technical Activity funds

COMPUTATION OF THE HARDNESS OF CARBON STEELS* R.M. FISHER,

Center for Advanced Materials, Lawrence Berkeley Laboratory. University of California, Berkeley. CA. 94720

The linear "law of mixtures" that is commonly used to predict or explain the strength of composites and "dual-phase", i.e., ferrite-martensite steels, can also be utilized to compute a very good estimate of the hardness of a variety of carbon steel products. Input parameters are simply the carbon and alloy content and the cooling rate from which the volume fraction and the hardness of the austenite decomposition product and the hardness of the ferrite phase are determined on a semi-empirical basis. This approach is particularly useful for evaluating the sensitivity of finished steel products to processing variables. *This work is supported by the Director,Office of Energy Research, Office of Basic Energy Sciences,Materials Sciences Div. of the U.S. Dept. of Energy under Contract No. DE-AC03-76SF00098.

(5:00 p.m.) APPARENT ACTIVATION VOLUME OF POLYCRYSTALLINE ALUMINUM, C. Y .. Tsai

and D.J. Quesnel, Dept. of Mech. :8ngrgo and Materials Science Program, University of Rochester I RPchester, NY 14627.

(3:00 p.m.) THE CYCLIC PRESSURE DISTRIBUTION AT AN EXPLOSIVELY WELDED ALUMINUMSTEEL INTERFACE: A. Szecket, O.T. Inal and D.J. Vigueras, Center for Explosive Technology Research, New Mexico Institute of Mining and Technology, Socorro, NM 87801 The pulsating nature of the pressure during explosive welding has been substantiated both by experimental evidence and previous theoret i ca 1 predi cti ons. For further veri fi cat i on of thi s phenomena, an experiment was undertaken utilizing aluminum to steel explosive welds with and without an i ntermedi ate n i cke 1 depos it on the stee 1 base plate. In the initial experiments, an aluminum flyer plate was welded to a mild steel base plate with the weld exhibiting a straight interface and no discernible formation of Fe-Al intermetallics. The formation of the Fe-A1 intermetallics were then induced through anneals of the weld at 550 C for periods of 2, 4 and 8 h followed by metallographic and microhardness characterizations. The distribution of the intermetallic, especially in the shorter duration anneals, clearly reveal the aformentioned pulsating nature of the explosively induced pressure. The second phase of the experiments consisted of electrodeposited of a thin (NO.013 mm) layer of nickel onto the mild steel base plate prior to the explosive joining. The cyclic distribution of poc~ets of nickel in the straight Fe-Al interface observed 1n the welds 1S taken as a further verification of the pulsating nature of the pressure waves in explosive welding. (3:30 p.m.)

Apparent activation volume was measured over the temperature range -20°C to lOOoC. Strain rate change test, hysteresis loop analysis and stress relaxation were performed in an MTS system over the strain rate range 5xlO- S to SxlO- 3 sec- 1 • It is fOWld that apparent activation volumes I evaluated by different experimental methods have different values. The difference between the largest and the smallest is more than three orders of magnitude. The competition between dislocation density and velocity is the dominating mechanism during the deformation process. Discussion in terms of Orowan equation as well as possible microstructural mechanisms corresponding to the variation of activation volume will be presented.

METALLURGY OF JOINING OF MATERIALS II Sponsored by TMS Physical Metallurgy and Solidification Committees Monday, February 25, 1985 2:00 p.m.

Washington Suite Sheraton City Squire

Session Chairman: Marty Glicksman, Renssalear Polytechnic Inst., Troy,

NY

A WAVY VERSUS A STRAIGHT HlTERFACE IN THE EXPLOSIVE WELDING OF ALUMINUM TO STEEL: A. Szecket, O.T. Inal, D.J. Vigueras and J. Rocco, Center for Exp 1os i ves Techno logy Research, Socorro, NM 87801 Although wavy interfaces produced in explosive welding have been considered ductile and strong, our experiments relating to the welding of aluminum (1100) to mild steel base plates indicate that a straight interface at the weld exhibits better mechanical properties and heat treatment behavior. The Fe-Al intermetallics, observed, metallographically; at the melt pockets of the vortices of each weld, reveal an adiabatic temperature rise associated with a wavy interface that render rather poor adhesion properties for the explosively produced welded joints. Systematic anneals and the subsequent microstructural and mechanical property characterizations of the straight interface in the Al-mild steels welds, on the other hand, exhibit no intermetallic formation initially and anneals of up to 8 h at 520 C do not seem to lead to the initiation of such alloying at these explosively joined materials. In this second effort we systematically characterize structural and mechanical property features of straight interfaces explosively generated in A1/mild steel welds and compare these clads to corrrnercially produced wavy interfaces in the joining of these two materials. The study conclusively exhibits the superior properties of the straight interface in explosive joining of specific materials. (4:00

p.m.)

BREAK

(2:00 p.m.) SOLID-STATE BONDING OF TUNGSTEN-RHENIUM ALLOYS: T. G. Nieh, Metallurgy Laboratory, 0/93-10, B/204, Lockheed Palo Alto Research Laboratory, 3251 Hanover Street, Palo Alto, CA 94304 Ni has successfully been usSd as an interleaf material to join W-26Re between 900 and 1400 C. The bond strength was found to depend on the temperature and stress at which the bonding process was conducted. It was also found that Ni reacts with the parent metal and forms a Ni-W-Re ternary compound. The formation of the compound causes significant embrittlement in the parent material. The compound first nucleates at the grain boundary and then grows into the grain. Quantitative studies of the growth kinetics of the ternary compound and the effect of the compound on the bond strength wi 11 be di scussed. Joining of W-26Re by diffusion bonding has also been successfully demonstrated. A brief discussion of the bonding parameters, e.g., surface conditions, temperature and applied pressure will be presented.

(4: 15 p.m.) EXPLOSIVE WELDING OF Ti-318 TO MILD STEEL SUBSTRATES: O.T. Inal, A. Szecket, D.J. Vigueras and H-r. Pak, Center for Explosives Technology Research, New Mexico Institute of Mining and Technology, Socorro, NM 87801 The unique specific strength and corrosion resistance of Ti-318) (Ti-6% Al-4% V) have rendered this alloy corrrnercially very desirable for aerospace appl ications although the thermomechanica1 treatments necessary for the attainment of a (ex + S) phase mixture and the base cost of the titanium metal make this alloy to be overpriced. The cladding of thin sheets «15 mm) of this alloy, on the other hand, on surfaces that require the enhanced properties would reduce the cost of its use and make it fe'lsible for commercial application. The study to be presented is the characterization of a straight interface produced in the explosive joining of Ti-318 a1ioy to a mild steel base plate. The techniques of metallography (optical and SEM and transmission electron microscopy were utilized in the structural characterizations while microhardness bending and tensile testing procedures were used to evaluate mechanical properties of the explosively produced welds. The interfaces were a.1so tested, using SEM and the energy dispersive X-ray attachment of this unit, for the presence of alloy formation at these welded jOints.

(2:30 p.m.) DIFFUSION BONDED STRUCTURES OF TITANIUM ALLOY:'

B. W. Kim,

Northrop Corporation, Aircraft Division, Hawthorne, CA 90250 The result 5 are discussed of an on-gOing research and development program to implement in production titanium sandwich structures that involve super plastic forming (SPF) and diffusion bonding (DB). This program will demonstrate the production feasibility and the repeatability of the SPF/DB process in a product ion environment. The program is being

(4:45 p.m.) EXPLOSIVE WELDED SINGLE CRYSTAL COPPER PLATES: Han-ryong Pak, O.T. Ina1, O.J. Vigueras and A. Szecket, Center for Explosive Technology Research, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801 Explosive welding is a technique through which various metal and alloy sheets are bonded. Although the. variety of explosively welded products are increasing the metallurgical effects of such bonding remains virtually unknown. In the study presented, single crystal

TMS-AIME Annual Meeting Program - 29 copper plates were chosen as a model material to elucidate some of the metallurglca1 phenomena that take place at a dynamically welded interface. Copper plates (app. size: 130 x 40 x 3-4 mm) in a single crystal fonn, grown by Bridgman technique, were explosively welded using an ANFO powder explosive in a parallel stand-off configuration. Bonded interfaces thus produced were both straight and wavy in nature. Tensile tests were made of samples cut out of the bonded interface as well as the shock-wave hardened copper matrix of the adjoining sections. Fracture and defonnation properties were examined by means of optical, scanning and transmission electron microscopy. Data obtained from these analyses will be used in the comparison of the wavy versus the straight bonded interfaces and their similarities as well as differences will be reported. Subseq'Jent annealing properties will also be studied and compared for the two interfaces.

MICROBIOLOGICAL EFFECTS ON METALLURGICAL PROCESSES I Sponsored by the TMSISME HydrometallurgylChemical Processing Joint Committee and the TMS Physical Chemistry Committee Monday, February 25, 1985 2:00 p.m.

Commonwealth Suite Sheraton Centre

Session Chairmen: L. A. Haas, Twin Cities Res. Ctr., U.S. Bureau of Mines, Minneapolis, MN 55417; J. A. Clum, Chern & Met. Engr., U. of Alabama, University, AL 35486

(2:00 p.m.) MICROBE-MINERAL INIERACTIONS IN THE LEACENG OF COMPLEX SULFIDES: K.A. Natarajan, Dept. of Metallurgy, Indian Institute of Science, Bangalore 560 012, India, and 1. Iwasaki, Mineral Resources Research Center, Univ. of Minnesota, Minneapolis, MN 55455. Alternative processing techniques are needed for dlfficult-tobeneficiate complex sulfide ores. Initial bulk flotation followed by selective (bacterial) leaching of the bulk concentrate could serve as viable hydrometallurgical routes in the processing of many multi-metal sulfide~. This paper discusses microbe-mineral interactions of interest in the le.aching of complex sulfides with respect to: (a) Direct bacterial attachment and its role in mineral dissolution, (b) Role of galvanic interactions in selective oxidation. Bacterial leaching test$ conduc ted on are and bulk concentrate saJ;Ilples of a copper-nickel sulfide and a lead-zinc-copper sulfide, using Thiobacillus ferrooxidans, are discussed.

(2:30 p.m.) EFFECTS OF OJ<.'YGEN MASS TRANSFER ON CHALCOPYRITE LEACHING BY THIOBACILLUS FERROOXIDANS*: O. Rego Minteiro and A.E. Torma, Dept. of Metallurgical and Materials Engineering, R&D Division, New Mexico Institute of Mining and Technology, Socorro, NM 87801.

The study investigated the extraction of copper from a chalcopyrite flotation concentrate using an adapted strain of T. ferrooxidans and a batch reactor. The rate of oxygen mass transfer was optimized using sodium sulfite solutions and the rate of oxygen consumption was measured by the dynamic out-gassing method during bacterial leaching. A direct relationship was found between the rates of oxygen consumption and copper extraction. The minimum oxygen requirement for unconstrained bacterial growth was determined. The power requirements of the process were calculated for the optimum leaching conditions. The apparent activation energy of chalcopyrite oxidation by T. ferr00xidans was estimated from the data of Warhurg respirometer studies. A flowsheet has been proposed for the bioextraction of copper from chalcopyrite flotation concentrate. *This study was supported in part by a DOl Grant No. G1124135.

(3:00 p.m.) CONTRIBUTION TO THE BIOLEACHING STUDY OF COMPLEX PYRITIC ORES: Jean Frenay, Jacques Wiertz, and Corneille Ek, University of Li~ge, Department of Non-Ferrous Extractive Metallurgy, Liege, Belgium.

Bacterial leaching tests have been carried out on Portugese pyritic ores containing zinc, copper, lead and silver as valuable elements. Both indigenous and isolated strains of Theobacillus ferrooxidans were used. During t}:le tests the factors pH, Eh and dissolved oxygen were measured and related to the leaching activity of the bacteria. Different means to estimate or determine the real bacteria concentration were examined. The influence of nutrient media and particle size has been evaluated. The role of galvaniC couples was studied by electrical linking of mineralogical samples of pyrite, sphalerite and chalcopyrite. Leach residues were examined by optical microscopy to follow the mineralogical alterations during the leaching. The results show a rather good leaching of the sphalerite. However, the dissolution of copper from chalcopyrite is much more difficult, 50% recovery never being obtained. Competing processes are compared by a kinetic analysis.

(3:30 p.m.) FATE OF SULPHIDE SULPHlJR IN BACTERIAL OXIDATION OF SULPHIDE MINERALS: !L.~ Kandemir, Murdoch University Mineral Science, Perth, W.A., 6150, Australia. An experimental study of the bacterial oxidation of naturally occurring high-purity sulphide minerals (ZnS, FeS 2 , Fel_xS, CuFeS2' CuZS, CuSFeS4) is presented using a mesophilic strain of T. FerrooKidans. As well as metal analysis and solution pH, partitioning of sulphide sulphur into elemental sulphur and sulphate ions has been monitored as a function of leach time. Partially oxidized sulphide substrates have been characterized e t regular time intervals by X-ray diffraction methods and extr:...cellular organic compounds reporting into leach solution have been identified by thin layer chromatography. The significance of the results in selective flotation of sulphides, coal desulphurisation, agglomeration is discussed.

(4:00 p.m.) THE SILVER CATALYZED BIOLEACH PROCESS FOR COPPER CONCENTRATES: R.W. Lawrence, A. Vizsolyi, R.J. Vos, R.P. Hackl, and A. Bruynesteyn, B.C. Research, Vancouver, B.C., Canada, V6S ZLZ.

A process for copper extraction from chalcopyrite and quantitative conversion of sulphide sulphur to elemental sulphur instead of sulphate, in a silver-catalyzed biological leach, will be discussed. Ini tial chemical activation of chalcopyrite concentrate with silver thiosulphate occurs in the presence of cupric sulphate. The activated concentrate is then biologically leached at an oxidation potential below 680 mV SHE, at ambient temperature and a tmospheric pressure to produce copper in solution and elemental sulphur. Copper is recovered by solvent extraction and electrowinning. Silver catalyst is recovered in high yield, together with unreacted chalcopyrite, follOWing sulphur removal, for recycle to the activation stage. Economic aspects of the process and its possible applications are discussed.

(-+:30 p.r::t.) Jiscussion.

MODELING THE EFFECTS OF ENVIRONMENT ON DEFORMATION AND FRACTURE II: Mechanisms and Atomic-Level Models Sponsored by the ASM Technical Activity, "Computer Simulation in Materials Science" Monday, February 25, 1985 2:00 p.m.

Diplomat Room Sheraton Centre

Session Chairmen: John H. Holbrook and Alan J. Markworth, Battelle, Columbus Laboratories, Columbus, OH 43201

(2:00 p.m.) FUNDAMENTAL THEORY OF FRACTURE: Standards, Gaithersburg, MD.

R.M. Thomson, National Bureau of

This lecture will highl ight the broad aspects of a theory of fracture in materials which are considered to be fundamental to an understanding of material toughness, and especially of those dramatic changes in toughness associated with changes of basic fracture mechanism at the crack tip. The respective roles of the atomic structure and bonding at the crack tip, external environment, the shape of the tip, and dislocation shielding will be explored. New results on mixed mode loadings and time dependent effects wi 11 be presented.

(2;35 p.m.) DYNAMIC MODELING OF CRACK PROPAGATION: David M. Cooper and Timur Halicioglu, NASA-Ames Resarch Center, Moffett Field, CA

94035 A molecular dynamic technique based on the Nordsieck-Gear algorithm has been used to model the formation and propagation of a crack in both two and three dimensional lattices. Simulations were performed for systems containing up to 10,000 particles with· each of the particles treated discretely. Both perfect crystals and crystals with existing cracks were modeled. In this study, a uniaxial load with progressively increasing intensity was applied to the system until a slip or crack occurred (perfect crystal) or until the crack propagated (crystal with existing crack). The effect of hydrogen on the crack propagation was investigated. A semiempirical potential function comprising two-body and three-body interactions was used to model the interaction of H atoms with BCe iron. The parameters of the potential were obtained by fitting the results of an all-electron effective core potential calculation of Fen-H interaction.

30 - TMS-AIME Annual Meeting Program (3: 10 p.m.) THE INFLUENCE OF FILMS ON NEAR CRACK TIP DEFORMATION AND FRACTURE:* K. Sieradzki and G. J. Dienes, Brookhaven National Laboratory, Upton, NY 11973 and A. Paskin, Queens College of CUNY, Flushing, NY 11367

Brittle fracture is known to occur in ductile metals in certain gaseous and aqueous environments. These environments almost always form reaction products in the form of thin solid films on the metal surface. Molecular dynamiC simulations were used to study the behavior of cracks coated with thin films in 2D triangular Lennard-Jones and Johnson solids. The important parameters investigated included elastic modulus, film-substrate misfit, and film thickness. The major result is that films with a larger lattice parameter than the substrate promote dislocation generation at the film-substrate interface while films with a sma ller la t tice pa rame ter inhi bi t crack tip dis loea tion generation and promote brittle fracture. *This work supported by U.S. Department of Energy, under Contract No. DE-AC02-76CH00016 at BNL and at Queens College by the National Science Foundation under grant number DMR/830l775.

boundar1es in the Cu Au phase and interphase boundaries between Cd 3 AU and disordered phase are reported and special features are discussed. This work was partly supported by U. S. Army Research Office (2:45 p.m.) ELECTRONIC STRUCTURE AND STABILITY 0'"' HOME-ROTHERY PHASES: U. Mizut9.ni* and T.B. Massalskit, *Dept. of Crystalline Materials SC"ier..ce, Faculty of Engineering, Furo-cho, Chjkusa-Ku, Nagoya l..t64) Jar-an; tDept. of Me+.allure:iclil Engineerine ann Mat.er5_als ScienC'e, C'arneg~e-Hellon Universit::{, Pittsburgh, PA 15213. r.the ~tabil:ity of the well known Hllme-Rothery pr..asE's which arA mostly based nn the noblp. metals haR bepn invariably linked to the electron concentration and through it to the related Fermi surface considerations and the density of states. Recentl;.", some of these parameters have been explored j n detail w:i.th many different tec:h>")iques, not only in cryst~lline HumlC"-Rothery phases, but also in the so-called. uHllJTle Rothery met.allic gla~sesu. P. brief Furyey l·rill be pre~ented of the more rec~nt res'. . .lts on the ~lectronic structure of Hurne-Rothery phases j ncluding the stabilj ty arguments related to t,he OCC'lJrr""nce of mete,llic glasses,

(3:45 p.m.) VACANCY MOTIONS IN AN ALUMINUM BICRYSTAL:

P. S. Ho and T. Kwok,

IBM Watson Ctr., Yorktown Hts., NY 10598, T. Nguyen, C. Nitta and ~, MIT, Cambridge, MA 02139 Vacancy jumps in a L: = 5 tilt boundary of Al have been observed by molecular dynamics simulation using an empirical interatomic potential function and a pseudopotential. An extensive study was made of the minimum energy (zero temperature) structure, to be used as initial configuration for subsequent simulations at elevated temperatures. An analysis of the distribution of the ob.::;erved vacancy jumps to various sites in the grain boundary core will be presented. Comparison of present data to previous resul ts for a bcc structure (a-Fe) and the sensitivity of the observed kinetics to details of the potential function will be discussed. To circumvent the difficulty of acquiring atomic jump statistics over a sufficiently long time period, a method of Monte Carlo simulation is implemented which makes use of the transition probabili ty between discrete sites which is generated by molecular dynamics. As an extension of this work, the motion of impurity particles in the presence of a grain boundary will be studied.

(3:30 p.m.) MAGNETISM IN AU-FE SOLID SOLUTIONS: Paul A. Beck, Dept. of Metallurgy, University of Illinois, Orbana, lL, 6180l. Information on the magnetic properties of f.c.c. Au-Fe solid solution alloys, as revealed by experimental studies of the magnetization, of the Mossbauer spectra and of neutron magnetic scattering, is reviewed. Based on this information a self consistent picture of the spin structure of these alloys is presented which qual itatively accounts for the observed properties as a function of temperature, and of alloy compositi on. (4:15 p.m.) INFLUENCE OF ATOMIC ORDER ON ELECTRONIC PROPERTIES OF CUX ALLOYS:

C.L. Foiles, Michigan State Univ., East Lansing, MI. When X == Pd, Pt, or Au, these alloys can exist in two conditions-atomically disordered (U) or atomically ordered (G).

(4:20 p.m.) ATOMISTIC MODELING OF THE INTERACTION OF MOLECULAR HYDROGEN WITH IRON SURFACES: * Alan J. Markworth and Luis R. Kahn, Bat telle,

Columbus Laboratories, Columbus, OH

43201.

The embrittlement of metals exposed to a hydrogen-containing atmosphere begins with the interaction of hydrogen molecules with the metal surface. Atomistic calculations of this interaction were carried out, for an iron surface, using a non-pairwiseadditive Fe-H potential that was obtained using the London-EyringPolanyi-Sato formalism. Effects of surface defects (vacancies, adatoms, ledges) and of surface stresses on the energetics and on other features of this interaction were evaluated. The results are discussed in this presentation together with their implications relative to hydrogen embrittlement.

*This research was supported by the National Science Foundation under Grant DMR82-17945.

a

PROCESSING I: DISSOLUTION AND PROCEE CONTROL Sponsored by the TMS Physical Chemistry Committ and the PTDlISS Monday, February 25, 1985 2:00 p.m.

PHASE DIAGRAMS, ALLOY PHASE STABILITY AND THERMODYNAMIC ASPECTS OF NOBLE METAL ALLOYS II: Theory of Stability, Electronic and Magnetic Structure Co-sponsored by TMS Committee on Alloy Phases, ASM Alloy Phase Diagram Data Committee and ASM-MSD Thermodynamics Committee Monday, February 25, 1985 2:00 p.m.

Versailles Terrace Sheraton Centre

Session Chairman: W. B. Pearson, Departments of Physics and Chemistry, University of Waterloo, Waterloo, Ontario, N2L 3G1

(2:00 p.m.)

PHASE DIAGRAM AND APB, IPB CALCULATIONS OF Au-Cu-Ag SYSTEMS, Ryoichi Kikuchi, Hughes Research Labs., 3011 Malibu Canyon Rd., Malibu, CA 90265 Solid state phase diagram calculations of Au-Cu and Au-Cu-Ag will be reported. The cluster variation method was used with the tetrahedron as the basic cluster. The results agree well with experiments. Monte Carlo calculations of the same system will be commented on. Also calculations of antiphase

In the U

condition the alloys are totally miscible, have a FCC structure and their electronic properties show a smooth variation with alloy conc.entration. Over wide concentration ranges near the stoichiometries of 3: 1, 1: 1 J and 1: 3 transformation to a G condition occurs. The resultant crystal structure and the affect of atomic order upon the electronic properties vary with the elements and the concentrations. The CuAu system has been studied extensively and data for the CuPd and the CuPt systems have become sufficient to document some trends in electronic properties. A detailed summary of electronic properties--stressing electrical conductivity, thermopower, Hall effect, magnetic susceptibility, and optical properties--will be presented and several trends in behavior will be discussed.

Dominion Sheraton Cent

Session Chairmen: J. W. Evans, Dept. of Materials Science and MineJ Engr., U. of California, Berkeley, CA 94720; J. H. Poveromo, BethlehE Steel Corp., Homer Research Lab., Bethlehem, PA 18015 (2:00 p.m.) "FERRIC CHLORIDE LEACHING OF SPHALERITE-AN ELECTROCHEMICAL

APPROACH", G. W. Warren, H. Henein, Z-M. Jin*, Dept. of Metallurgical Engineering and Materials Science, Carnegie-Mellon University, Pittsburgh, PA 15213, *Chengdu University of Science and Technology, Chengdu, Sichuan, THE PEOPLE'S REPUBLIC OF CHINA.

Previous studies have shown that the kinetics of dissolution of sphalerite in ferric chloride solutions are controlled by an electrochemical, charge-transfer, surface reaction. The reaction is one-half order with respect to Fe 3+ and has an activation energy of 58.4 kJ/mole. The electrochemical nature of this reaction system has been further investigated by separating the individual, anodic and cathodic half cell reactions using a dual-cell apparatus. The effect of solution variables (Fe3+/Fe2+ ratio, Fe 3+ concentration, and Cl- concentration) On the polarization curve for each half cell were then independently measured. In addition the mixed potential and mixed current were measur~d as a function of electrolyte composition. Results indicate that CI- participates directly in the anodic reaction. This is consistent with leaching experiments which indicate an order of 0.25 with respect to [CI-] at lower concentrations changing to zero order at higher concentrations. Electrochemical measurements are compared .with leach~ng experiments in similar electrolytes and an analytlcal model .1S provided which accounts for the observed effects of [Cl-].

TMS-AIME Annual Meeting Program - 31 (2:25 p.m.) "A STUDY OF THE KINETICS OF Ag 2S ELECTROCHEMISTRY IN H2SO"

SOLUTIONS", D.W. Price, B. Drouven*, C.W. Warren, Dept. of Metallurgical Engineering and Materials Science, Carnegie-Mellon University, Pittsburgh, PA 15213, *Preussag AG, Coslar, West Germany. The electrochemisty of AgZS in H2 S0 4 solutions is described by cyclic voltammetry, supported with potentiostatic and galvanostatic studies. The anodic portion of the Ag 2 S polarization curve shows an increase and subsequent passivation of current density. The initial increase in current is explained by the oxidation of A..g 2 S to Ag+ and gO. A two-step charge transfer limiting mechanism is used to model this portion of the polarization curve. At higher overpotentials, passivation occurs due to the deposition of Ag 2 S04 on the electrode surface, which is correlated with a paralinear model of film growth. Rotating disk electrode studies show diffusion control at high overpotentials. The diffusion coefficient for Ag+ calculated from these data is consistent with literature values and can be used to estimate current levels at high overpotentials.

(2:50 p.m.)

KINETICS OF DISSOLUTION OF ZIRCONIUM AND COLUMBIUM IN LIQUID STEEL: P.G. Sismanis and S.A. Argyropoulos,Dept of Mining and Metallurgical Eng., McG~ll University,

3450 University St., Montreal, Quebec, CANADA, H3A 2A7 The rate of dissolution of Zirconium and Columbium in liquid steel has been studied under carefully controlled experimental conditions. The tests involved immersion of pure Zirconium and Columbium cylinders in 65 kg baths of qui scent and agitated steel. A microprocessor-based facility was used to monitor the dissolution in a 'dynamic-way'. It was found that the exothermicity of mixing plays an important role on dissolution kinetics. The dissolution of Zirconium proceeds faster than the dissolution of Columbium. This phenomenon was explained on the basis of higher heat of Mixing which Zirconium exhibits when it was dissolved in liquid steel than Columbium. Experimental results for ferrozirconium and ferrocolumbium dissolution in liquid steel will also be presented.

(3:15 p.m.) "THE EFFECT OF Ag+ON THE ANODIC ELECTROCHEMISTRY OF CuFeS

and the melting of scrap. Permissable ranges of power arc voltage, and phase angle are defined. The implications in terms of computer applications, electrode positioning control, electrode consumption, power supply, and supply circuit perturbations are also explained.

(4:30 p.m.)

DEVELOPMENT OF A REFINED FERRO-CRROMIUM-NICKEL MASTER AlLOY FOR HIGH-ALLOYED STEEL PROCESSES:* w. Dresler, Laurentian University, Sch. of Engineering, Sudbury, ONT., Canada. The utilization of low grade North American chromites requires beneficiation leading to a 100% agglomerated ore concentrate for the reduction in submerged arc furnaces. Under these conditions, high C and Si contents must be tolerated in the FeCr alloy· in order to keep the Cr losses within economic feasibility. A process for refining this high-C Cr alloy is described when e.g. lowcost NiO sinter and 02 are applied at ratios of Cr to Ni close to two. The activity raising effect of Ni on C in liquid FeCr permi ts efficient C removal down to ranges of low-C ferro-alloy quality while Cr losses are minimized. Experimental results are supported by thermodynamic interpretations. This process can advantageously be adapted to stainless steel production technology. The low C and Si contents of the FeCrNi alloy additions will substantially reduce the 02 treatment periods and the refractory wear of the vessels. *This work is supported by Natural Sciences and Engineering Research Council of Canada.

PROCESSING METHODS AND PROPERTIES OF ADVANCED CERAMIC MATERIALS II Sponsored by the TMS Chemistry and Physics of Metals Committee Monday, February 25, 1985 2:00 p.m.

Georgian Ballroom B Sheraton Centre

Session Chairmen: F. V. Nolfi, Jr., U.S. Dept. of Energy, ER-131, GTN, Washington, DC 20545; R. O. Scattergood, Dept. of Materials Engineering, Box 7907, North Carolina State University, Raleigh, NC 27695-7907 IN

H2 SO SOLUTIONS", D.W. Price, B. Drouven*, G.W. Warren, Oept. of Metallurgical Engineering and Materials Science, Carnegie-Mellon University, Pittsburgh, PA 15213, *Preussag Ag, Goslar, West

(2:00 p.m.)

Germany. Chalcopyrite leaching processes are catalyzed by small additions

of Ag+ to the leaching solutions.

X-ray diffraction shows evi-

dence of a Ag 2 S intermediate on the chalcopyrite surface. Cyclic voltammetry has been· used to investigate the effect of Ag+ on the electrochemistry of CuFeS in sulfuric acid electrolytes. In addition anodic and cathoaic half reactions were decoupled USing a dual cell apparatus. Experiments were conducted for CuFeS 2

anodes in H2S04 electrolytes with a Fe 2+/Fe 3+ couple as the cath-

ode. An increase in corrosion current density occurs as Ag+ concentration in the anolyte increases. The studies show that the Ag+ catalyzes the anodic reaction and not the Fe 3+ reduction. Above lO-2M Ag+, however, corrosion current decreases, due to Ag2S04 deposition on the mineral surface. Mass balances were conducted from potentiostatic experiments with CuFeS 2 in H2 S0 4 ' Ag+ electrolytes. Current efficiency data is subsequently used to explore possible mecbamisms of silver catalysis.

(3:40 p.m.)

ADVANCED CERAMIC PROCESSING METHODS H. Palmour III, North Carolina State University, Raleigh, NC From the orocessing viewpoint, many advanced ceramic materials wi 11 be complex. Not only wi 11 the app 1 i cat ions be very demanding; but economic mass production of a variety of intricate shaoes, sizes and types wi 11 be needed. They wi 11 have to be created and realiably densified from "reluctant" constituents that are typically refractory, hard, and often less-than-ideal in terms of purity and uniformity. Some of the problems--and some of the demonstrable successes--being encountered in upgrading and/or augment i ng estab 1i shed cerami·c process methods to better meet the challenging demands embodied in new applications of advanced ceramic materials are considered. Amonq them are novel methods for powder production and/or condi t i oni ng, cl eaner milling/blending practices, attaining uniformity of compaction in green ware, better control of binder burnout, and the design of rational, thouch often nonl inear, heat treatment schedules for rate controlled densification of oolyphasfc ceramic materials, i ncl udi ng those whi ch sinter in the presence of 1i qui d ohase.

MICROPROCESSOR CONTROL OF METALLURGICAL FURNACES: S.A. Argyropoulos, B. Closset and o. Albaharna, Dept. of

M~n~ng

and Metallurgical Eng., McGill University,

3450 University St., Montreal, Quebec, CANADA, H3A 2A7 Using microprocessor systems which were developed in Metallurgical lab, automatic control was implemented for two metallurgical ,furnaces. The first furnace was a resistance furnace and it was· used to study the phase diagram of Aluminum Strontium. The second was an induction furnace and it was used to measure the microexothermicity of additions in liquid metals. Real time software was developed through which the microprocessors control tbe furnace operations. In this paper hardware and software aspects of furnace control will be presented along with some operating examples.

(4:05 p.m.)

THE ELECTRICAl CHARACTERISTICS OF ARC SMELTING FURNACES: J. Persson, Lectromelt Corporation, Pittsburgh, PA

A fundamental mathematical analysis of single- and threephase arc-smelting furnace circuits is depicted in the form of curves developed on a computer monitor. The number of curves is restricted to highlight phenomena that are significant in power and process control for the smelting of silicon alloys, ferro chromium and refractories,

(2:45 p.m.) THE RELIABILITY OF CERAMICS: THE ROLE OF TOUGHNESS: A.G. Evans, Department of Materi a 1s Sci ence and Mi nera 1 Engi neeri ng, UniverSity of California, Berkeley, CA 94720 The reliability of ceramics is predicated on the minimization of flaws by process control, the development of enhanced fracture toughness and the app 1i cat i on of nondestruct i ve test methods. This presentation describes the role of toughness in the development of rel iable cerami cs. Four predomi nant tougheni ng mechani sms are ope rat i ve in cerami c systems: trans format i on toughening, microcrack toughening, deflection toughening and fi ber tougheni ng. Trans format i on and mi crocrack tougheni ng involve crack shielding. Such toughening mechanisms are temperature and particle size sensitive. Transformation toughening is the more potent of the crack shielding mechanisms, primarily because of the non-damaged character of the transformed materi al ahead of the crack tip. Deflection toughening exhibits less potent i a 1 than trans format i on tougheni ng, but has the advantage that the toughness is retai ned 1:fl el evated temperatures and is particle size insensitive. Fiber toughening is unique amongst the tougheni ng mechani sms, in that complete mat ri x fractu re may precede final failure.

(3:25 p.m.)

Break

32 - TMS-AIME Annual Meeting Program (3:35 p.m.)

(2:40p.m.) "EFFECTS OF PARTICLE SIZE ON THE SURFACE COMPOSITION OF A Ni-Pd

HIGH TEMPERATURE CREEP OF STRUCTURAL CERAMICS: Robert F. Davi s, North Carolina State University, Dept. of Materials Engineering, Box 7907, Ra 1 ei gh, NC 27695-7907.

ALLOY", David O. Groomes*, Paul Wynblatt, Dept. of Metallurgical Engineering and Materials Science, Carnegie-Mellon University, Pittsburgh, PA 15213, *General Electric Company, Battery Business Division, Gainesville, FL 32607. Thin films of a Ni-l a/o Pd alloy, ranging in thickness from 5 to 100 A, were deposited onto alumina substrates by R-F sputtering. The films were subsequently heat treated to produce small particles of the alloy with average sizes in the range 300 to 1000 A. The surface composition of aggregates of small particles was determined by Auger electron spectroscopy after equilibration of the samples at about 650°C. Average particle sizes were determined by analysis of photomicrographs taken by a variety of electron microscope techniques. The results show a strong dependence of surface composition on particle size. The significance of these results will be discussed in the light of current models relating surface composition to particle size.

As a result of the current need for a wide variety of structural material s for various appl ications at high temperatures, cons i derab 1 e interest has developed concern i ng creep phenomena in high melting point ceramics. The focus of the review will be an investigation of the effects of bond type, crystal structure and microstructure on the kinetics and mechanisms of creep in, and the app 1 i cabil i ty of, cerami c materi a 1 s often cons ide red for employment under stress at elevated temperatures. The materials to be considered include MgO, transition metal carbides (e.g., TiC x and NbC x ) , A1203' SiC and Si 3N4 •

Research supported by the National Science Foundation under

(4: 15 p.m.)

grant DMR-8116864.

ENVIRONMENTAL EFFECTS ON THE PROPERTIES OF NON-OXIDE CERAMICS, R.E. Tressler, Penn State University, 201 Steidle Building, University Park, PA 16802 The 1oad-beari ng capabi 1i ty of non-oxi de cerami cs in corrosi ve enviroments depends in a complex wayan the applied stress, the time of stress application and the corrosion-induced microstructural changes in the ceramic. The static fatigue limit is the fundamenta 1 parameter whi ch determi nes the upper 1 imi t of applied stresses or stress intensities which can be supported by a given material for long campaigns. Our recent studies of oxidation effects on the fatigue limit at elevated temperatures of sintered silicon carbide and reaction sintered carbide will be discussed along with studies from the literature.

(3:00 p.m.) KINETIC MECHANISMS FOR S AND Sb SEGREGATION TO FREE SURFACES IN Ni-l wt % Sb AT 700·C:* C. L. White, Oak Ridge National Laboratory, Oak Ridge, TN, and W. Losch, PEMM/COPPE, Universidade Federal de Rio de Janeiro, Brazil Results from scanning Auger electron spectroscopy (SAES) analyses of Ni-l wt % Sb containing 30 wt ppm S that indicate different mass transport mechanisms for segregation of sulfur and

antimony to the free surface at 700·C. Polycrystalline specimens were heated in the SAES analyses chamber, and the distribution of Sb and S were mapped after various heating times. Antimony appears to saturate on the surface withing a few minutes, and its distribution is consistent with mass transport

by lattice diffusion.

Sulfur, on the other hand, initially

appears only where grain boundaries intersect the free surface and then slowly spreads over the surface. This observation pro-

vides direct and graphic evidence for the role of short circuit

SURFACES AND INTERFACES

diffusion in surf ace segregation phenomena.

TMS-AIME General Abstract Session Monday, February 25, 1985 2:00 p.m.

Imperial Ballroom B Sheraton Centre

Session Chairman: A. Joshi, Lockheed Research Labs., D/9310, Bldg. 204, 3251 Hanover Street, Palo Alto, CA 94304

(2:00 p.m.) RECOVERY AND RECRYSTALLIZATION OF PIM ALUMINUM ALLOY 7091: Youn~-Won Kim. Metcut-Materials Research Group. P.O. Box 33511. rlght=t'aRerson AFB. OH 45433 and W. M. Griffith. Air Force Wright Aeronautical Laboratories. Materials Laboratory. AFWAL/MLLS. Wright-Patterson AFB. OH 45433

PIM aluminum alloy 7091 was studied to determine its recovery and recrystallization characteristics that occur in extruded material after cold working. When consolidated and extruded. this precipitation hardened alloy is characterized by fine grains and finely dispersed powder surface oxide breakups. Extruded material was annealed fully to produce coarse ("'1 ~m) precipitates and then rolled at room temperature to various reductions. Both fully annealed and cold-worked specimens were heat treated isochronally and isothermally. Their annealing response was monitored by hardness measurements and by OM and TEM observations. The results are compared with those from the counterpart conventional alloy 7075. The role of oxide breakups on recrystallization and the effects of cold work amounts on the recrystallized grain size will be discussed.

(2:20 p.m.) RECRYSTALLIZATION OF VERY DILUTE TERNARY COPPER ALLOYS·: K. T. Kembaiyan and Bernard Gallois, Stevens Institute of Technology, Hoboken, NJ 07030 Softening temperatures and activation energies for recrystallization in the systems Cu-Mn-Te, Cu-Ni-Sb and Cu-Ti-Se have been measured by conventional time-temperature anneal ing methods. Certain of these alloys which contain less than 100 ppm total additions exhibit Significantly higher softening temperatures than would be expected from a consideration of the individual binary systems while preserving electrical conductivities of the order of 100% lACS. The highest recrystall ization temperatures are observed for specific ratios of metalloid to metallic solute concentration. The results of the macroscopic measurements and of Auger spectroscopy conducted on fractured specimens will be used to discuss possible mechan isms of the synergi s ti c interact ions between the so 1 utes. ·Supported by the International Copper Research Association.

*Research sponsored by the Division of Materials Sciences, U.S. Department of Energy under contract DE-AC05-840R21400 with the Martin Marietta Energy Systems, Inc. (3 :20 p.m.) ON THE MEASUREMENT OF SURFACE FREE ENERGIES OF SOLIDS:· J. H. Schneibel, Metals and Ceramics Division, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, TN 37831; and L. Martinez, Institute of Physics, National University of

Mexico, A.P. 20-364, 01000 Mexico, D.F., Mexico. A method for measuring surface free energies y of cavitated

polycrystalline solids by analyzing distributions of cavity radii is described. After annealing at low tensile stresses, y can in principle be determined independently of the kinetics of cavity growth or sintering. The influence of internal stress distributions on the accuracy of the suggested technique is modeled and discussed.

*Research sponsored by the Division of Materials Sciences, U. S. Department of Energy under contract DE-AC05-840R21400 with the Martin Marietta Energy Systems, Inc.

(3:40 p.m.) CHARACTERIZATION OF SURFACE RESIDUES ON WATER-ROLLED ALUMINUM SHEET:

M. G. McKimpson, AReO Metals, Arlington Heights, IL

An investigation was undertaken to characterize the nature and origin of the surface re.sidue which forms on M-IIOO aluminum sheet rolled using a commercial waterbase lubricant. This residue was investigated using optical and electron microscopy, X-ray diffraction, Auger microscopy and chemical analysis. These results show that the residue consists primarily of residual lubricant and wear debris, rather than corrosion products forme.d by reaction with the water present. A qualitative model for the deposition of this residue on the surface of the sheet is proposed.

(4:00 p.m.)

*

'IHE NAWRE OF SURFACE SEGREGATICN IN 'IEmARY SYSTEMS: T. J. Licata and J. M. Sanchez, Heruy Kn.mlb School of Mines,

CoiUiiib1a Un1versity, Roan 1124, New York City, New York

10027.

The phenarenon of surface segregation in tel'l1aIY systems is

studied using a regular solution rrodel based on nearest neighbor pair interactions. The appearance and classification of concentration oscillations close to the surface are discussed in tenns of ~ijering' s eight categories of tel'l1aIY regular solutions. Several exper:iJrental systems are treated to illustrate the trends observed in the results of the rrodel calculations.

* This

work was supported by the National Science Foondation

TMS-AIME Annual Meeting Program - 33 (4:20 p.m.)

(9:40 a.m.)

CALCULATION OF ION IMPLANTATION PROFILES UNDER PREFERENTIAL SPUTTERING: M. Rangaswamy and D. Farkas, Dept. of Mats. Engg., Virginia Poly tech. Inst. & State Univ., Blacksburg, VA 24061 Concentration versus depth profiles were calculated for ion implanted materials taking into account the preferential sputtering he c lculation was based on numerical of one of the elements. solutions to the diffusion equations. The method took into account the lattice dilation due to implantation and the diffusion processes that result from the depletion of the preferentially sputtered component at the surface. FOI· low diffusivity values the effects of preferential sputtering were found to be confined to the surface; but as higher diffusivity values were used the effect on the total retained dose at steady state became significant.

TMS-AIME Annual Dinner/ Awards Reception/Show 6:00 P.M. Monday, February 25, 1985 Hilton Hotel

TUESDAY AM ADVANCES IN TITANIUM WELDING III: Process Advances Sponsored by the TMS Titanium Committee Tuesday, February 26, 1985 8:30 a.m.

Jefferson· Suite Sheraton City Squire

ELECTRICAL PROPERTIES AND DEOXIDIZING POTENTIALS OF FLUORIDE-BASED FLUXES FOR ELECTRO SLAG AND SUBMERGED ARC WELDING OF TITANIUM: A. Block-Bolten, J. Landers and D. R. Sadoway, Massachusetts Institute of Technology, Cambridge, Massachuset ts. A flux suitable for electroslag welding titanium must be optimized with respect to two properties: electrical conductance and deoxidation potential. A low electrical conductance causes the generation of adequate heat at moderate operating currents to weld thick section material. A high deoxidation potential causes the flux to become active in refining oxygen out of the molten weld metal. The compounds that are expected to deoxidize best are not the same ones that are expected to decrease electrical conductance. In this study a totally new electrical conductance cell has been constructed. The electrical conductance of CaF2-based melts is being measured as a function of composition and temperature. Deoxidation experiments consist of arc melting titanium buttons and candidate fluxes on a water-cooled copper he2rth. Chemically pure titanium when arc melte~ under optical grade fluxes consisting of various combinations of C&F., MaF. and SrF. typically gave oxygen levels of 700 - 1100 ppm and nitrogen levels below 100 ppm.

(10:15 a.m.) CONTACT TIP WEAR IN GAS-METAL ARC WELDING OF TITANIUM. K. T. Ulrich, T.W. Eagar, Rm. W59-224, M.I.T., Cambridge, HA 02139 When titanium wire is used in gas-metal arc welding, copper contact tips wear more rapidly than when ste-l wire is used. This wear is accompanied by arcing between the base plate and the contact tip instead of between the base plate and the filler wire, a phenomenon called "burnback." Burnback requires a complete shutdown of the welding operation and is therefore an expensive problem. Experiments were run to understand the mechanism of contact tip failure. The results of these experiments reveal that the low thermal conductivity of titanium causes melting to occur at the sliding electrical contact junction between the filler wire and the contact tip. Melting and subsequent free:1ing of titanium at the contact point can either bui!d up and cause jamming of the filler wire in the contact tip or can cause adhesion of a chunk of titanium to the filler wire thai then abrades the copper contact surface. The mechanism leading to the jamming of wire in the contact tip led to burnback in several of the experimental cases.

Session Chairmen: B. A. MacDonald, Office of Naval Research, Code 431, 800 N. Quincy Street, Arlington, VA 22217; W. A. Baeslack III, Department of Welding Engineering, The Ohio State University, Columbus, OH 43210

(10:50 a.m.) (8:30 a.m.) A REVIEW OF TITANIUM WELDING PROCESSES: D. F. Hasson, Dept. of Mechanical Engineering, U. S. Naval Academy, Annapolis, MD 21402 The efficient and cost-effective util ization of conventional and advanced titanium alloys in structural appltcattons has required the advanced development of several welding processes. These developments have been promoted to a great extent by the high reactivity of titanium as compared to other commonly-welded structural metals, but also by titanium's unique physical and metallurgical properties. This review wf11 discuss the current state-of-the-art of welding processes for titanium, concentrating on arc and beam welding processes. Recent advances in processes designed to weld thicknesses ranging from thin sheet to heavy plate will be discussed. The presentation will deal· primarily with advances in the U. S., however, work conducted abroad will al so be considered.

INCREASING CONTACT TIP LIFE DURING GAS METAL ARC WELDING OF ~i:!~~: ~ ru~&!e and W. E. Lukens, DTNSRDC, Code 2815, Gas metal arc welding is an electric arc welding process in which a consumable electrode is continuously fed to the weld pool. Current is supplied to the wire electrode from a copper contact tube through which the wire passes prior to exiting the welding torch. While transferring current to the wire, the contact tube must withstand heat .radiated from the arc as well as abrasion from the moving wire. These two phenomena may result in the premature failure of the contact tube through burn back , the

~!t~~!am~;~!r s o~ft~~e f~~*~~c~i~~b:ngo~~e d~~~;~~~ ;~~e~h~r shielding

tao mfxture on the continuous

wear.

service life of the

~m:~~~u ~o~~~~t i~~g:tM~;e~i~m, ~:: ~m!daI~0:e6~69f-~t

to 0.140-in. Shielding gas was either 100% Ar, 75% Ar: 25% He, !lr 70% Ar: 30% He. Results indicate that contact tube service life increases nonlinearly with increasing bore diameter, achieves a plateau, and then decreases nonlinearly, suggesting a minimum and maximum bore diameter working range. With the introduction of helium into ·the Shielding· gas the continuous service life of the contact tube appears to increaae at a faster rate than with pure argon. Theae phenomena and their causes will be discussed.

(9:05 a.m.) WELD METAL GRAIN REFINEMENT BY ELECTROMAGNETIC STIRRING: W. E. Lukens and R. DeNale, DTNSRDC, Code 2815, Bethesda, HD 20084 The proposed mechanisms which operate to refine weld metal grains when the weld pool or welding arc is subjected to motioo imposed by a magnetic field include reduction of weld metal thermal gradients, melting off of secondary dendrite arms, and dendrite tip fragmentation. According to the theory of constitutional supercooling, the first proposed mechanism will promote dendrite growth, which is the solidification mode required for grain refinement by both periodic remelting and tip fragmentation. These mechanisms were investigated in the Ti-6Al-4V alloy by periodically remelting the solidification front through electromagnetic arc deflection, and by generating weld pool motion to create increased shear between solid and liquid at the interface. Thermal gradients in the weld pool were measured. Factors related to alloy system which affect mode of solidification, such as slope of the liquidus and solute distribution coefficient are discussed in terms of

grain refinement.

(11 :25 a.m.) COMPARISON OF PULSED AND CONTINUOUS LASER WELDING OF TITANIUM ALLOYS: Robert Webb and Richard J. Coyle, Jr. AT&T Technologies, Engineering Research Center, P.O. Box 900, Pri nceton, New Jersey 08540 The aim of this work was to optimize the mechanical integrity of the weld zones in several titanium alloys formed by both pulsed and continuous laser welding. Both 90-degree butt joints and overlapped geometries were studied with respect to metallurgical behavior, tensile and shear strength, changes in ductility and microhardness, and corrosion resistance. Three different laser types were utilized, namely: pulsed Nd:YAG, pulsed CO 2 and continuous CO 2 ; all at average power levels up to several hundred watts. At such laser power levels, weld zones with one to two millimeter penetration were ac~ievable. Both overlapped spot and continuous seams were formed in which mechanical strength exceeded that of annealed base alloy materials. It was further shown that computer numerical weld simulation techniques could model the ovserved thermal behavior in both fusion and heat affected zones. Results of comparative experimental and computer-modelled behavior in several titanium alloys are presented in this paper.

34 - TMS-AIME Annual Meeting Program ALUMINA & BAUXITE II: Bayer Process Development Sponsored by TMS Light Metals Committee Tuesday, February 26, 1985 8:30 a.m.

Royal Ballroom B Sheraton Centre

Session Chairmen: Carlos M. Padial, Martin Marietta Aluminum, Box 165 Kingshill, St. Croix, Virgin Islands 00850; Joseph L. Anjier, Kaiser Aluminum, P.O. Box 1031, Baton Rouge, LA 70821

(8:30 a.m.)

MASS TRANSFER STUDIES ON WET OXIDATION OF BAYER LIQUOR - PILOT PLANT EVALUATION: P. J. The, F. S. Williams and J. D. Guthrie, Aluminum Company of America, Alcoa Technical Center, Alcoa Center, Pennsyl vani a 15069 A pi lot scale investigation has been conducted to obtain data on the oxygen absorption accompanied by oxidation of organic compounds in Bayer spent liquor. Such studies will be of value for the design of wet oxidation equipment. The effects of oxidation temperature, total operating pressure, and oxygen and liquor rates on the overall oxygen transfer coefficient, Kr,a, have been studied. A 7.6 cm (3.0 in.) diameter nickel colOmn, packed with 1.2 cm (0.5 in.) monel raschig rings, was used in these experiments. The rate coefficient was found to be significantly affected by oxidation temperature. Below the loading range the mass flow rate of o.xygen had a less significant effect. For scale-up procedure a mathematical model predicts that for the same oxidation condition, the controlling vari ables requi red to produce the same oxygen transfer rate are liquor superficial velocity and column height. (9:00 a.m.) LIQUOR PURIFICATION - WET AIR OXIDATION J. Matyasi, Almasfuzito Alumina Plant, Hungary P. Siklosi, ALUTERV-FKI J Budapest Hungary S. Ziegenbalg, FNE, Freiberg, CDR

(10:30 a.m.) BAUXITE RESIDUE PROPERTIES AND THE REHABILITATION OF MUD LAKES By L. K. Walker, R. J. Parker, S. J. Gibson, Golder Associates West Perth, Western Australia. A detailed geotechnical programme has been undertaken at Alcoa's Kwinana refinery since 1978 to define the engineering properties of bauxite residues with respect to strength, permeability, grading and consolidation characteristics. The definition of these parameters has enabled engineering analyses to be performed for planning the rehabilitation of red mud lakes. Aspects covered by the analyses include dewatering by various methods, long-term settlement prediction for planning of drainage works, and calculations of bearing pressures and differential settlements for planning of light industrial developments. Future directions indicated by the results achieved to date are outlined.

(11:00 a.m.) EURALLUMINA PROGRESS IN PROCESS PRECIPITATION CONTROL OF ALUMINUM TRIHYDRATE: S. Perra, Eurallumina S .p.A., Portoscuso, Sardinia, Italy. Since Eurallumina start-up in 1973 up to now, preCipitation control at Eurallumina may be divided in two main ages: before and after population balance control. With the introduction of population balance control and at fill caustic concentrations of 195 TC, in the precipitators there was a decrease of particles and an increase of weight average diameter. On the contrary, in t~e classification area we observed nucleation and a decrease of the weight average diameter. The importance of these conclusions are: (a) even during fines crises the precipitation parameters are maintained more steady and at the maximum allowed by plant equipments, (b) knowing the origin of the crises (mainly in classification) we may concentrate the efforts to achieve a better performance in the ,area where the problem arose.

(11 :30 a.m.)

The trend towards stricter specifications for hydrate and alumina as well as improved energy effiCiency of higher concentration process liquor has resulted in the need for process liquor purification.

FURTHER ADVANCES IN THE FILTRATION OF ALUMINA TRIHYDRATE: Ronald F. Nunn and Robert M. Talcott, Dorr-Oliver Incorporated, 77 Havemeyer Lane, Stamford, CT 06904.

Short descriptions are given for liquor purification processes developed in Hungary and GDR including: hydrate wash water evaporation and crystallization of its carbonate and oxalate content; salting out evaporation of spent liquor, and ignition of the organics-rich sodium carbonate; wet air oxidation of spent or strong liquors, crystallization of its carbonate and oxalate content and treatment of the resulting salts. Pilot and commercial plant results are included.

As part of an on-going program we reported last year on an

extensive study of the effect of process and operating variables on the filtration - washing of alumina trihydrate in Bayer plants. Further leaf tests have explored hydrate filtration under conditions much less than ideal and added substantiation to previous results.

(9: 30 a. m. )

Various modifications have been made on field units in line with indicated improvements, giving confirmation of predicted performance.

RESIDENCE TIME DISTRIBUTION STUDIES IN PREDIGESTION DESILICATORS: L. N. Schooler, Reynolds Metals Company,

Benefits obtainable with various dewatering aids have also been detemined.

Corpus Christi, Texas:- - - - Desilication studies in the laboratory are typically conducted in batch systems with known residence time

distributions

(RTD).

Plant

scale

unit

operations

are

accomplished in continuous reaction vessels. These vessels may be either mixed or unmixed vessels. The true RTD's of particles in these systems are seldom known. A tracer technique has been developed which can be used to measure the RTD I S in either pilot or plant scale reaction vessels. This technique can be used to determine the benefit that may be derived from additional mixing or to determine the minimum level of mixing necessary to approach stirred tank reactor performance.

CARBON TECHNOLOGY II Sponsored by the TMS Light Metals Committee Tuesday, February 26, 1985 8:30 a.m.

Georgian Ballroom A Sheraton Centre

Session Chairmen: P. G. Campbell, Alumax of South Carolina, P.O. Box 1000, Goose Creek, SC 29445; M. F. Vogt, Kaiser Aluminum & Chemical Corporation, P.O. Box 1600, Chalmette, LA 70044

(10:00 a.m.) SAFETY RELIEF SYSTEM FOR MEDIUM PRESSURE DIGESTION PLANT: By K. Fort. Swiss Federal Institute of Technology, Zurich Institute of I::n-ergy Technology.

The satety reliet systems for digestion plants have to be designea for large flows of boiling liquids. The task is to calculate the required orifice area of rel1ef valves for digestors, flash vessels and discharge piping.ln must cases the flow is limited by the phenomena of critical (sonic) velocity, which is for tlashing mediums astonishingly small. The d1fferent components of the digestion area are analyzed for the critical case. W1th the USE of modern microprocessors for interlockIng the risk of activating the relief devices 1S reduced. The outlined pr1nciples are illustrated on the example of the Interalumina digestion plant which has been success tully started up in early 1983.

(8:30 a.m.) HEAT TREATMENT STUDIES OF ANODE AND CATHODE CARBONS: S. R. Brandtzaeg, H. A. f/Jye, Institute of Inorganic Chemist;Y:University of Trondheim, N-37034 Trondheim-NTH, Norway, Ardal Sunndal Verk A.S., N-5875 Ardalstangen, Norway. Four different anthracites, Three petrol cokes and One pitch coke have been identically heat treated under controlled conditions. The temperatures and holding times were varied in the region 1400-2800 o C and 40-1640 minutes, respectively. Analysis of chemical and physical properties showed considerable differences between the different anthracites and the different cokes. A model is used to describe the electrical conductivity of anthracites. Changes in electrical conductivity of petrol cokes is found to correlate with the puffing effect.

TMS-AIME Annual Meeting Program - 35 (9:00 a.m.)

THE PROBLEM OF SECONDARY QI DETERMINATION: G.R. Rdmovacek, Koppers Company, Inc., Monroeville, PA, P.E. Plantz, Leeds & Northrup, St. Petersburg Since heat treated and straight distilled pitches do not perform exactly the same in the carbon plant, it is important that the carbon plant operators have a sensitive analytical tool available for the assessment of the degree of heat treatment to provide them a guideline for measures to be taken when pitches produced by di'fferent operations are switched. Secondary QI is formed by liquid phase heat treatment of pitch. It is different from primary QI formed by vapor phase cracking of tar vapors. Secondary QI is formed by the same process as mesophase, which is partially solub1e in qui no 1i ne and, therefore, not the same as secondary QI. Six pitches with known concentration of secondary QI were analyzed on the concentration of mesophase, and the isolated QI were analyzed on C/H ratios and on particle size distribution by low angle forward scattering light from a lazer· beam projected through the sample. The results indicate which of these procedures has the greatest chance of meeting the needs of carbon plant operators. (9:30 a.m.)

CALCINING PETROLEUM COKE IN OXYGEN FIRED ROTARY KILNS: D. R. Ma son, Reynolds Meta 1s Company, Ba ton Rouge, LA. and Harold C. Rolseth, Union Carbide Corporation, Tarrytown, N. Y. Decontrol of natural gas prices and the rapid rise of fuel costs in the last few years have greatly added to the expense of rotary kiln operation. A method of injecting pure gaseous oxygen has been developed whereby petroleum coke volatiles and solids are effectively burned to maintain kiln temperature control without a resulting loss of overall coke recovery. This paper reviews the history of the development of oxygen firing, the comparative anal'ysis of coke produced by identical kilns (calcining a split of green coke) fi red by natural gas and oxygen and an overview of projected savings in fuel costs. (10:00 a.m.) A NOVEL MErHOD FOR QUANTIFYING TYPE3 OF QUINOLINE INSOLlJll1E!3

IN PITCH: K.E.T0rklep and M.Sorlie, EIkem als, R&D Center, N-4620

VAGSBYGD,Norw"¥.

The quality of SOderberg anode peate is significantly affected by the presence of primary and secondary quinoline insolubles (QI) in the binder pitch, but their determination is problematical. Existing methods quantify secondary QI (mesophase) by a tedious and unreliable microscopic examination, or it is estimated from a C/H analysis. No method for the direct determination of primary QI has been reported. We have found that microwave radiation is absorbed by pitch in direct proportion to the content of primary QI, while the pitch matrix and mesophase spheroli tes appear to be completely transparent to microwaves. By combining a precision laboratory microwave unit with a simple differential calorimeter, we have determined directly the amount of primary QI in anode pitches from several producers, and also mesophase as total QI - primary QI. The method is non-destructive, fast, accurate and simple. Total equipment costs in the preliminary series of investigg.tions were about 00$ 3000·

(10:30 a.m.) Rt:ACTIVITY TESTING OF ANODE CARBON MATERIALS: G. J. Houston,

H. A. 0ye, Institute of Inorganic chemistry, University of Trondheim, N-7034. Trondheim-NTH. Norway.

A range of carbon samples taken from typical anode materials has been tested, in a laboratory-scale test apparatus, for their likelihood to contribute towards the excess anode consumption. 0 Reactivities were meas\.PI'ed in a flowing stream of CO 2 at ca.950 C and, separately, in a flowing stream of air at ca.500 o C:-The results indicate that when reactivities are measu-;ed by these methods, the main detectable influence is that due to the presence of catalytic anode impurities. The strong catalysts Na (for the C/CO

z

reaction) and V (for the C/0 2 reaction)

exerted the main effects, whereas the presence of other known catalytic impurities were of minor importance at the concentrations encountered.

ENERGY REDUCTION TECHNIQUES IN METAL ELECTROCHEMICAL PROCESSES III Sponsored by TMS-AIME Electrolytic Processes Committee Tuesday, February 26, 1985 8:30 a.m.

Versailles Ballroom Sheraton Centre

Session Chairmen: Thomas J. O'Keefe, Dept. of Metallugical Engineering, MRC, University of Missouri Rolla, Rolla, MO 65401; Douglas J. Robinson, DREMCO, 8832 E. Holmes, Tucson, AZ 85710

(8:30 a.m.) ELECTRODEPOSITION OF ALLOYS:

M.F. Mathias and T.W. Chapman,

Chemical Engineering Department, University of Wisconsin, Madison, WI. The composition, structure, and uniformity of electrodeposited alloys depend on bath chemistry, transport effects, and electrode kinetics. Experimental and theoretical techniques have been developed to study the interactions of these effects with plating conditions and to determine critical system parameters. A rotating disk electrode is used to form deposits and to evaluate polarization effects, and microscopic analyses, including STEM, ar·e done to characterize the deposits. Results are presented for zinc-nickel deposits on steel.

(9:00 a.m.) MECHANISM OF NODULE INHIBITION IN THE ELECTROREFINING OF COPPER:

T.N. Andersen, Kennecott-Process Technology.and F.A. Olson, Department of Metallurgy. University of Utah. A principal cause of anode-cathode short circuits and cathode contamination in copper electrorefining is nodules. which originate from suspended conductive particulates (e. g., anode slimes) that get entrapped or occluded in the cathode deposit. A laboratory study was conducted to determine the effect of process parameters on the initiation and early growth of nodules. These parameters included diffusion layer thickness, temperature. current density and concentration of the typical addition agents (thiourea. animal protein or glue. and chloride ions). An accelerated test method was applied wherein the nodulation was induced by suspending copper powder or commercial refinery slimes in the test cell. A great variation in nodulation was produced over the ranges of the variables encountered in tankhouse operation. The results show a complex synergism among the parameters, and indicate that multiple processes are in effect ~hich include control by both inhibition and mass transport of Cu + ions. These results will be discussed in light of fundamental electrochemical properties of the system (e. g .• polarizat ion curves) and existent theories of levelling.

(9:30 a.m.)

EFFECT OF ELECTROLYTE IMPURITIES AND ALUMINUM CATHODE DIP PRETREATMENT ON ZINC DEPOSIT ADHESION. R. Kal1l11el and Mustafa Goktepe, Technische Universitat Berlin, Strasse des 17. Juni 135, 1000 Berlin 12, BRD. With test cells using tankhouse electrolytes and stripping apparatus the i nfl uence of the electro lyte impuriti es 1ead, cadmi um, cobalt, nickel, tin and antimony on the adhesion behaviour of the zi nc depos its on a1umi num cathodes has been determi ned. I nvestigations with the aim to control and adjust the zinc deposit adhesion even under critical electrolysis conditions reveal that for favourable stripping performance sufficient reduction of the adhesive strength can be achieved by a simple and inexpensive dip pretreatment of the aluminum cathodes in aqueous solutions e.g. with sodium resinate as parting addition. (10:00

a.m.)

Break

(10:30 a.m.) INFLUENCE OF MORPHOLOGY ON CADMIUM CEMENTATION FROM ZINC SULFATE

ELECTROLYTE: T. J. O'Keefe. M. Blaser. J. Cuzmar, K. Jibiki, O. Mirkovic. Dept. of Metallurgical Engr .• MRC. University of Missouri Rolla. Rolla, MO 65401. Impurities present in zinc sulfate electrolyte used for electrowinning can often have a major influence on the product obtained. Because of this. it is necessary to minimize the concentration of undesirable impurities such as cadmium, copper. cobalt and nickel. Cementation processes using zinc dust as the reducing agent are most commonly used to remove the impurity ions. The present study involved an evaluation of the influence of certain electrolyte components on the morphology of the cementation residue obtained. Tests were conducted on both a batch laboratory scale as well as on a larger, industrial mini-plant. which was designed to approximate continuous plant operations. The importance of the morphology of the cementation product on the physical condition and handling characteristics of the residue is discussed. It was also found that the physical characteristics of the solids influenced the reaction rate for impurity removal and the quantity of zinc dust required for the reaction.

36 - TMS-AIME Annual Meeting Program (11:00 a.m.)

(9:30 a.m.)

INFLUENCE OF ATOMIZ!lV ZINC ALLOYS AND OF ANTIMONY VALENCE STATE,; ON IMPURITY REMOVAL FROM ZINC ELECTROLYTE BY CEMENTATION: Robert C. Kerby, CornineD Ltd., Trail, B.C., Canada VIR

ELECTROCHEMICAL EVALUATION OF ZINC SULPHATE ELECTROLYTE CONTAINING COBALT, ANTIMONY AND ORGANIC ADDITIVES: Thomas J. O'Keefe and 1'1ark W. l~ateer, Materials Research Center, University of Missouri-Rolla, Rolla, Missouri 65401.

4L8. Addi (ions of Sb(V) or SbF 6 - to zinc electrolyte were more effective than Sb(lll) additions in promoting the removal of cobalt and nickel from solution by cementation, particularly wh'=!l1 atomized zinc alloys containing 0.1 to 2 wt% lead were used. Alloying additions such as aluminum, aatimony or iron to atomized zinc reduced the effectiveness of atomized zinc in removing impurities from solution. The detrimental effects could be moderated somewhat by the addition of lead to the zinc alloys. The effects of atomized zinc alloys and antimony valence states were less pronounced for cadmium and copper cementation from zinc electrolyte than for cobalt and nickel cementation.

( 11 : 30 a. m.

The effects of cobalt, s-napththol, glue and antimony on the polarization behavior of acid zinc sulfate electrolytes were studied using cyclic voltammetry. It was found that s-naphthol was beneficial in reducing the detrimental effects of cobalt while antimony and excess glue were each harmful. An optimum initial overpotential was found to 'exist which minimizes the harmful effects of cobalt for the given solution. Monitoring the rise in current on a zinc deposit potentiostated at a potential just slightly cathodic to equilibrium was used to indicate optimum conditions. A two-additive system was shown to be desirable in order to control cobalt and antimony containing electrolytes. The structure of the deposits was examined using scanning electron microscope techniques.

(10:00 a.m.)

INFLUENCE OF COPPER ON CURRENT-AND ENERGY-EFFICIENCES OF THUM ELECTRO-REFINING CELL FOR SILVER: B.K. Chadwick and Y.K. Rao, Department of Material s Science and Engineering, University of Washington, Seattle, WA 98195.

THE INFLUENCE OF LiF AND BATH RATIO ON PROPERTIES OF HALL CELL ELECTROLYTES: S. Young and R. O. Loutfy, ARCO Metals Company, Research and Development, Primary Metals R&D, Tucson, Arizona 85726.

The effect of adding copper to the electrolyte in the Thum electro-refining cell for silver hos been investigated. The copper contents ranged from 2.8 gpl to 56.9 gpl. As the copper concentration is increased, while keeping the silverconcentration constant, the energy efficiency of the cell improves markedly: as copper content rose from 2.8 gpl to 15.8 gpl, the energy consumption fell from 3.14 kwh/kg silver to 1.09 kwh/kg silver. The effect on current efficiency, however, is very s 1i ght. Hi gh copper-contents result in the contamination of the cathode silver product. Optilljum operating conditions that ensure minimum energy consuption and entail negligible product contamination have been identified.

The effect of LiF additions on liquidus temperature and ~lectrical conductivity over a wide range of cryolite bath ratios (1.0 to 1.5 weight ratio) was investigated. Results did not agree with multiregression ~ations reported by Dewing and Choudhary over the entire region. New regression equations were developed. Reasons are given for the differences. The models are used to discuss the economic implications of LiF additions to Hall cell electrolytes.

(10:45 a.m.) ELECTROLYTIC EXTRACTION OF MAGNESIUM FROM COMMERCIAL ALUMINUM ALLOY SCRAP: B. L. Tiwari, R. A. Sharma and B. J. Howie, Electrochemistry Department, General Motors Research Laboratories, Warren, MI 48090

HERBERT H. KELLOGG SYMPOSIUM: Hydrometallurgy and Electrochemistry Sponsored by The Physical Chemistry Committee and The Copper, Nickel, Cobalt and Precious Metals Committee Tuesday, February 26, 1985 8:30 a.m.

An electrolytic process, based on a three-layer concentration cell, to extract magnesium from aluminum alloy scrap has been developed. The process was tested at 1025K with two cells of different sizes: 0.6 kg and 5 kg feed aluminum. In both cells, the magnesium content of commercial aluminum scrap was selectively reduced from 1.1 to less than 0.1 wlo, at anodic current denSity as high as 1.1 A/cm 2 with current efficiency exceeding 85%. Magnesium was recovered in the form of sal tcoated globules. Comparison of performance for the two cells suggests that the process has scaleup potential.

Regency Ballroom Sheraton Centre

Session Chairmen: P. Duby, Columbia University, New York, NY 10027; W. P. Opie, AMAX Base Metals, R&D, Inc., 400 Middlesex Ave., Carteret,

NJ 07008

(8:30 a.m.) CONTRIBUTION TO CHLORIDE HYDROMETALLURGY: R. Winand, Universite Libre de BruxelJes, Ecole Poly technique, Faculte des Sciences Appliques, Avenue F.-D. Roosevelt, 50, 1050 Bruxelles, Belgium. The paper gives a synthesis of research work performed in the department during the last ten years and dealing with copper, cobalt and manganese electrodeposition in chloride aqueous solutions. Special emphasis is given to electrocrystalJization. Properties of the electrolytes, such as solubility limits, electrical conductivity, kinetic potential - pH diagram and complex ions stability are discussed in connection with leaching, purification of the electrolyte, and metal recovery. When possible, kinetic parameters and probable electrode mechanisms are given. Problems that are still to be ,Solved are also listed.

(9:00 a.m.)

COUPLED DIFFUSION IN THE LEACHING OF METALS: Milton E. Wadsworth, The University of Utah, Salt Lake Clty, Utah. Professor Kellogg early recognized the electrochemical nature of cyanidation. This paper reviews this work and extends his concepts to a variety of metals which involve coupled electrochemical diffusion proces·ses. The experimentally observed sharp transition from anodic to cathodic rate control can be explained by considering mixed potentials and diffusion limiting overvoltages. Similar results have been observed for other metals as well, including silver and copper.

(11:15 a.m.) THE FORMATION OF ANODIC FILMS ON PURE TIN AND ALLOYS IN STANNOUS SULPHATE ELECTROLYTES. Roland Kammel, Technische Universitiit Berlin, Strasse qes 17. JUnl 135, 1000 Berlin 12; Uwe Landau, Fa. Schempp & Decker GmbH & Co. Industriegalvanik KG, Am Stichkanal 6, 1000 Berlin 37; Bernhard Szesny, Fa. Hermann C. Starck Berlin, Werk Goslar, 0-3380 Goslar 1; West Germany. Stannous sulphate electrolytes are widely used today in electrolytic tin production. During the electrolysis so called black mud sl imes are formed on the anode surface which lead to an increase in ce ll-vo ltage. I n order to prevent excess i ve ce ll-vo ltages or even oxygen evolution the slimes have to be removed periodically. In modern electrolytic tin refineries automatic anode brush machines are employed to remove the mud at least every two days. Studies in laboratory scale have been performed about the effect of different impurities on the rate of mud formation on pure tin and tin alloys in stannous sulphate electrolytes. Organic additives have shown to be capable to decrease the rate of slime formation.

TMS-AIME Annual Meeting Program - 37 HYDROMETALLURGY/CHEMICAL PROCESSING I Sponsored by the Joint TMSISME Hydrometallurgyl Chemical Processing Committee Tuesday, February 26, 1985 8:30 a.m.

Senate Suite Sheraton Centre

Session Chairpersons: Gary A. Kordosky, Henkel Corporation, 1844 W. Grant Rd., Suite 104, Tucson, AZ 85745; John E. Pahlman, U.S. Bureau of Mines, 5629 Minnehaha Avenue South, Minneapolis, MN 55417

(8:30 a.m.)

It has been found that by reacting manganese dioxide with coal in an acidic solution, the tetravalent manganese is reduced and taken into solution. 'TIle reaction was strongly temperature dependent and the fastest rates were aChieved close to the boiling point of the solution. In the case of hydrochloric acid, the rate was faster than with sulphuric acid, and no oxidation of the chloride ion to chlorine was observed.

LIGHT METALS: SPECIAL SESSION-ECONOMICS, ALUMINUM SUPPLYIDEMAND AND ENERGY Sponsored by the TMS Light Metals Committee Wednesday, February 27, 1985

CYANIDE/THIOCYANATE REACTIONS ASSOCIATED WITH GOLD METALLURGY:

s. L. McGill and J. L. Hendrix, Generic Mineral Waste Treatment Center, Mackay School of Mines, Un i versity of Nevada, Reno, Nevada. Conditions and rates of reactions for the formation of thiocyanate from various sulfur species were investigated by the

Generic Waste Treatment and Recovery Center.

Constant

stirred, constant temperature reactors were used to react several individual sulfur species as well as some complex gold ores with pH buffered cyanide solutions. Cyanide distillation and the ferric nitrate thiocyanate determination methods were employed as analytical procedures. The effects of concentration of reactants, pH and temperature as well as inhibiting or catalytic effects of adclitives are presented.

(8:55 a.m.) ItDEVELOPMENT OF THE Me LAUGHLIN GOLD MINE FLOWSHEET," by Michael H. Conway, Davy McKee Corp . , San Ramon, CA, and John R. Turne y , Homestake Mining Co., Golden, co. Pressure oxidation of 3,000 tpd o f gold ore is required fo r hig h gold recovery at the McLaughlin Mine. As McLaughlin will be the first operating cormner c i al mine at this s cale requiring pressure oxidation of all of the ore, munero us case studies were necessary. The case studies concentrated on process requirements, capital cost, and operating cost. To fa c ilitate completion of the case studies a computerized heat and material bala nce s y stem was used for proc e ss evaluation. The results of the compute rized balances i n conjunc tion with capital and operating cost estimates were used to optimize the flowsheet and equipme nt.

2:00 p.m.

Royal Ballroom A Sheraton Centre

Stssion Chomnan: Helge Forberg, National. outhwlre Aluminum Company, Box 500. HawesviUe, KY 42348

THE FOLLOWING PAPERS WI LL BE PRESENTED BY : The Dynamics of Primary Aluminum Business - (Some will make it and some wi 11 not. Growth of demand and supply versus BNP.) Robin G. Adams, President, Resources Strategies, Inc .,300 V. No. Pottstown Plke, Exton, PA 19341 Effect of Increasing Power Prices of Primary Aluminum Producers (Changes which are taking place in the U.S. and abroad. The near and long-tenn effect these changes will have on the primary producers in the world.): Robert F. J. Butler, (Retired Former Director of Energy Affairs, 210 Walslnq Dr., Rlchffiond, Virginia 23229 Aluminum Market Outlook- Where the growth and demand will be and where the metal will come from in the next 5-10 years: Stewart Spector, President, The Spector Report, Inc., P. O. Box 467, Hewlett,NY 11557 Aluminum Recycling - The economic potential and limitations: James M. Creel III, Dir. of Technology & Quality Control, Reynolds Met~, P.O.Box 27003, Richmond, Virginia 23261 Planning for Change - Potential and problems facing the alumi num indo Kenneth J. Calhoun, Manager of Economics Analysis, Aluminum Co. of MI. 1501 Alcoa Building, Pittsburqh, PA

This p aper reviews dev e lopnent of the computer simulation, five major case studies, and the overall McLaughlin flowsheet.

MATERIALS ASPECTS OF SEMICONDUCTOR MA· TERIALS AND DEVICES I: OXYGEN IN SILICON Sponsored by the TMS Ad Hoc Electronic Device Materials Committee

(9:20 a.m.)

Tuesday, February 26, 1985 8:30 a.m.

NEW TECHNOLOGY FOR RECOVERY OF SILVER AND MANGANESE FROM MANGAN-

IFEROUS SILVER ORES, Clem~nt K. Chase, Joseph M•. Keane, K D Engine ering Co., Inc., Tucson, Arizona. Since the dawn of cyanidation leaching techniques for precious metals, certain manganese-bearing silver ores have been a probleql due to low silver extractions . Since simultaneous occurrence of silver and manganese is common in nature, this situation has made many otherwise ~ttractive silver deposits unecono· mic in the past. New knowledge and technology promise to change the economics of processing such ores. This paper discusses recent developments and presents an additional bibliography!

(9:45 a.m.)

i3reak

(10:10 a.m.) THE EFFECT OF FOREIGN IONS ON REOOX POTENTIAL OF THIOUREA

SOLUT10NS:* B. Pesic, University of Idaho, College of Mines, Moscow, 1D 83843 Thiourea a s a l i xiviant for precious meta:t.s, gold and silve r, is gaining a n inc reased interest. In prac tice , the a c cumulation of various ions in solution could affect the leaching condi tions, The redox po tential is one of the condi tions, and it wa s decided to be e xamined, The redox potential o f thiourea solutions, in sulfuric acid medium, was e xami~ed in function of concentration of the followin~ cations : Fe 3, Fe+2, Cu 2, Cu+1, Mn+2, Zn+2, Ni+ 2 , Ag+, Co+ , Cr+ 2 , and Na+,+The most. dramatic effect was found from the presence of Cu 2, Addit10n of thioure a in a solution wi th constant initial cation concentration reduced the redox potential in a l l cas es except with Cu+ 2 , 1tThis work was supported by Nationa l Science Foundatio n

(10:25 a.m.) TIlE USE OF COAL AND LIGNITE TO DISSOLVE MANGANESE DIOXIDE IN

ACIDIC SOLUTIONS: H.A. Hancock~ Department of Mining and MetallUrgical Engineering, Technical University of Nova Scotia, Halifax, Canada and D.J. Fray, Department of Metallurgy and Materials Science, University of Cambridge, Cambridge CB2 3QZ.

Princess Ballroom Sheraton Centre

Session Chairman: L. C. Kimerling, AT&T Bell Laboratories, 600 Moun· tain Ave., Murray Hill, NJ 07974 (8:30 a.m.) SOLID STATE REACTIONS OF OXYGEN IN SILICON:J. R. Patel, AT&T Bell Laboratories, Murray Hill, NJ 07974 The problem of oxygen in silicon has provided formidable and faSCinating challenges in both research and technology . Dissolved i n s~licon, oxygen is electrica lly neutral. Only upon heating is the incredibly complex behavior of oxygen in sil icon manifest . This talk surveys reactions in the solid state as crystals are heated through critical temperature ranges. At the very low end of the temperature scale (IOOe K) oxygen can trap vacancies to form the well- known A center. Proceeding up in temperature at 450°C we encounter the fonaation of donors, whose nature and origin still provides an active and exciting field of research . At these and higher temperatures ('\..650°C) we obtain the first direct microscopic evidence of ribbon-like defects and amorphous clusters, which give way at still hisher temperatures (BOO-IOOO·C) to a rich variety of defects such as platelike preCipitates, prismatic loops and stacking faults. At the very highest temperatures ('\..1200eC) we observe giant stacking faults and large polyhedral precipitates. It is a matter of some practical importance that the defects introduced influence both the mechanical properties of silicon and device proceSSing parameters.

(9:10 a.m.) OXYGEN IN SILICON:. DEFECT STRUCT RES AND PROPERTIES: James W. Corbett and Lawrence C. Snyder, SUNY/Albany, Albany, NY 12222-:-

Although it has been thirty years since Fuller et a1. first discussed the thermal donors in silicon, the identUication of the attendant defect structures and properties has not been completed. Recent years, however, have seen great advances and these will be reviewed, including IR, EPR, DLTS, and theoretical work. The emerging picture reveals a hierarchy of d ouble donors; this succession arises from an electrically active core to which is added a succession of oxygens. The proposed models f or the c ores will be surveyed. We will discuss how the recent kinetic studies of Suezawa and Sumino, the incis i ve DLTS measurements of Benton et ~., and the studies of other oxygen-related defects by Lindsttl:5m !:l~. sharply limit the acceptable models for the thermal donors.

38 - TMS-AIME Annual Meeting Program (9: 50 a.m.)

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(10:05 a.m.) THE SOLUBILITY AND DIFFUSION OF OXYGEN IN SILICON: L C. Mikkelse~, Xerox Palo Alto Research Center, Palo Alto, CA Reliable values of the solubility and diffusivity of 0 in Si are prerequisite to tne modeling of oxide precipitation and denudation-internal gettering. These parameters were determined from secondary ion mass spectrometry profiles on (100) and < 111) FZ and CZ Si wafers treated in H2 '80 and 180 2 at 600-1350°C. The diffusivity was found to depend primarily on temperature, whereas the "solubility" was also a function of the oxidizing ambient, increasing in Ule same sense as the linear oxidation rate constant, i.e., both are higher in steam ambients and for <111) orientations. The excess oxygen is metastable since it readily out-diffuses after removal of the oxidizing ambient and does nut produce defects revealed by preferential etching. In the absence of precipitation, 0 in-diffuses similarly in CZ and FZ wafers. Finally, the diffusivity of recoiled-O is enhanced in implantdamaged Si, but that of dissolved 0 is unaffected by backside damage. The present results are compared with those determined by other tech· niques and with values USed in modeling oxygen-related phenomena in Si.

(10:45 a.m.) OXYGEN PRECIPITATION IN SILICON: PHENOMENA, KINETICS, MECHANISM, AND EFFECTS, S. M. HUt IBM General Technology Division, Hopewell Junction, NY ~ The precipitation of oxygen in silicon is a very complex process affected by many factors. Oxygen often precipitates nonuniformly in striated patterns, even though its initial concentration may be very uniform. On the other hand J the temperaturetime-transformation curves tend to indicate a homogeneous process of nucleation. In $equential thermal processings, a high-temperature pre-annealing irreversibly retards the precipitation kinetics, whereas a low-temperature preannealing enhances it. An oxidizing ambient tends to retard the precipitation relative to annealing in inert ambients such as nitrogen, argon, and vacuum. All these phenomena are consistent with a nucleation model in which small vacancy clusters participate in the process, and explainable by a strain effect of phase change. The effect of oxygen precipitation on devices, internal gettering, and mechanical properties of the silicon substrates will also be discussed.

MECHANICAL BEHAVIOR OF RAPIDLY SOLIDIFIED MATERIALS III: Aluminum Alloys Sponsored by the TMS-Mechanical Metallurgy Committee and the ASM-MSD Flow and Fracture Activity Tuesday, February 26, 1985 8:30 a.m.

and .:Jging temperature and time. Detailed microstructural studies have shown that sr-rength is controlled by the volume fractions, sizes, and ~p.1cings of precjpitated 8; ('/\]3Li) and 1'1 (A121.iCu) p<1rticles. Ductilities of RSP AI-3I.i al10ys arc strongly influC'llcl'd by
Dou~~las

Indep('t1dl~nt

(9:20 a.m.) DEFORMATION BEHAVIOR OF PM Al-Li and Al-Li-Zr ALLOYS, Frank W. Gayle and John B. Vander Sande, Massachusetts Institute-or-Techno logy, Cambri dge, Massachusetts 02139. The present study focusses on deformation behavior of Al-Li and Al-Li-Zr extruded powder metallurgy alloys. The alloys, Al-2.3Li-1.1Zr and Al-2.2Li-0.1Zr, age harden through the precipitation of A13Li (Ii'). The Ii' precipitates in the low-Zr alloy in the expected fine-scale spherical morphology, however in the high-Zr alloy Ii' precipitates preferentially surrounding a very finely distributed A13(Li,Zr) phase (of the same L12 structure as Ii') which is present after a normal solution-heattreatment. The increased strength and ductility of the high-Zr alloy is attributed to differences in microstructure. The mi crostructure is di scussed before and after tens il e testi ng including the effect of Zr'on dislocation behavior. Tensile test results are presented. (9:40 a.m.) THERMOMECHANICAL PROCESSING OF A RAPIDLY SOLIDIFIED Al-Li-Mg-Zr ALLOY POWDER. S. Abeln and G. J. Abbaschian, 1-faterials Science and Engineering, University of Florida, Gainesville, FL 32611 Rapidly solidified Al-3%Li-5.5%Mg-0.2%Zr powder was hot extruded in vacuum, and its response to solution and precipitation heat treatments, and rolling deformation was examined. The results indicated that the majority of strength arises from high volume fraction of homogeneously distributed 0"', but this also results in heterogeneous planar slip due to the coherent nature of 0" and hence low ductility. The ductility remains low in the overaged conditions as the remaining 0'" is still sheared. On the other hand, the ductility and uniform deformation of the alloy was greatly enhanced when it was processed by a special technique. The elongation, Y.S., and T.S. of the material processed by the new technique were 5.5%, 38, and 61 Ksi, respectively, as compared with 2.2%, 48, and 65 Ksi for the conventionally peak-aged material. Research sponsored by the office of Naval Research under Contract No. N00014-81-K-0730, and the University of Florida.

(10:00 a.m.)

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Regency Foyer Sheraton Centre

Session Chairmen: G. J. London, Naval Air Development Center, Warminster, PA 18974; N. J. Grant, Massachusetts Institute of Technology, Cambridge, MA 02139

(8:30 a.m.) MICROSTRUCTURE AND FRACTURE BEHAVIOR OF RAPIDLY SOLIDIFIED ALUMI NUM ALLOYS: R. L Lewi s, Lockheed Palo Alto Research Laboratories, Palo Alto, CA 94304, and LA. Starke, Jr., University of Vir9inia, Charlottesville, VA 22901. PIM consolidation of RSP is being used to produce new Al-Li alloys having high modulus and low density. RSP Al-Li-Cu-Mg alloys having a good combination of mechanical properties have been developed. However, rapid solidification offers no advantage over cheaper ingot metallurgy processi ng if so 1i d so 1ubil i ties are not exceeded at the sol ut i oni zi ng temperature. I n order to take maximum advantage of the effect of lithium on density, a recent study has used rapid solidification to produce Al-Li alloys that exceed so 1ubi 1ity 1i mits. Two other approaches, one of which involves additions of Zr in excess of 0.4 wt.% and one of which involves Be additions, are also being examined. These alloys can only be produced by rapid solidification of particulate and PIM consolidation. This paper will describe the microstructures and mechanical properties of all of these low density a 1umi num alloys and will correlate thei r fracture behavi or with thei r mi crostructural features. (9:00 a.m.) HICROSTRUCTURE-HECHANICAL PROPERTIES CORRELATIONS IN RAPIDLY SOLIDIFIED Al-3Li ALLOYS:* P. J. Heschtcr, R. J. Lederich, P. S. PaD, und J. E. O'Neal, NcDoonell Douglas Research Laboratories, P. O. Box 516, St. Louis, flO 63166. Yield and ultimate tensile strengths of ,rapid solidification processed (RSl') Al-3Li-0.2Zr, A1-3Li-JHg-0.2Zr, and Al-3Li-2Cu-O.SZr alloys are strongly dependent on solution-treatment temperature

(10:10 a.m.) TENSILE AND MICROSTRUCTURAL PROPERTIES OF EXPLOSIVELY COMPACTED RAPIDLY-SOLIDIFIED AI-Li ALLOY POWDERS:' T. C. Peng, S. M. L. Sastry, J. E. O'Neal, and R. J. Lederich, McDonnell Douglas Resea.rch Laboratories, St. Louis, MO 63166. Rapidly solidified AI-lLi and Al-3Li alloy powders were explosively compacted into 2.5-cm-diameter cylinders under various explosive parameters. The as-compacted and heat-treated specimens were tested for tensile strength, Young's modulus, ductility, and hardness and examined for microstructural modifications. Similar studies were conducted on specimens prepared from extrusions. Mechanical properties from both the explosively compacted and extruded samples are compared and analyzed in terms of the observed microstructural features. *Research conducted under the McDonnell Douglas Independent Research and Development pr~grarn.

(10:30 a.m.) MECHANICAL PROPERTIES AND MICROSTRUCTURE OF NEil RS ALUMINIUM ALLOYS: M. J. Couper and R. F. Singer, Brown Boveri Research Center, CH-540S Baden, Switzerland One approach which can be taken in the development of aluminium alloys with improved high temperature strength is to combine RSR processing with element additions which have low diffusivity and low solubility in aluminium (e.g. Fe, Co, Mo, Ni, rare earths, etc.). The initial requirement is to, develop a microstructure of finely dispersed, stable, intermetallic particles. This paper will report on recent attempts to develop new alloys meeting the above criteria and the improvements in mechanical properties obtained. The alloys were compacted from RS powders produced at the Brown Boveri Research Centre on recently described equipment for ultrasonic, inert gas atomization. The high temperature strength and long term stability of alloys are compared with those obtained in the AI-Fe-Ce and AI-Fe-Ho systems.

TMS-AIME Annual Meeting Program - 39 (9:15 a.m.)

(10:50 a.m.) CHARACTERIZATION OF A1-Fe-Ce PLATE/SHEET PRODUCTS, S.L. Langenbeck, Materials and Processes, Lockheed-California Company, Burbank, CA 91520, G.J. Hildeman and D.K. Denzer, Alcoa Technical Center, Alcoa Center, PA 15069, and W.M. Griffith,

AFWAL/MLLS, WPAFB, OH

45433

Dispersion strengthened powder metallurgy aluminum alloys are being developed for structural applications up to 650°F. This research is being conducted under an AFWAL Materials Laboratory Contract, F33615-BI-C-S096, with Lockheed-Californa Company as prime contractor. The subcontractor, Alcoa! has conducted a rolling study of their AI-Fe-Ce alloy. Using extruded stock,

rolled sheet (0.040 and 0.125 inch thick) and plate (0.500 inch thick) products were fabricated. Mechanical property testing included room and elevated temperature tension, room temperature tension after long time elevated temperature exposure, creep, and fracture toughness. Exposure and test elevated temperatures were 300°F I 450°F and 600°F. Room temperature strength and ductility exceeds the property goals of 75 ksi ultimate, 65 ksi yield and 5% elongation. Results of the mechanical property evaluation will be presented. "

STRESS RELIEF CRACKING IN NUCLEAR PRESSURE VESSEL STEELS:* C. J. McMahon, Jr., D. H. Gentner and J-X. Sun, Department of Materials Science and Engineering, University of Pennsylvania,

Philadelphia, PA 19104 A study of the susceptibility to stress relief cracking in a large number of production heats of the two principal grades of steel used in U.S. nuclear reactors (A533-B and AS08-2) has been completed. Several heats of the forging grade used in European reactors (AS08-3) were also included. It was confirmed that the A.508-2 steel is considerably more susceptible to SRC than the other two steels, and this difference has now been established quantitatively. It is shown that the AS08-2 steel Ii es in a ccmple tely di ffe rent range of susceptibili ty, wi th no overlap with the other two steels. The reasons for this difference are now understood and can be explained on the basis of composition. These reasons will be discussed. *This work was supported by EPRI under contract No. RP 2060-4.

(9:45 a.m.) (11:20 a.m.) ASSESSMENT OF DURABILITY AND DAMAGE TOLERANT BEHAVIOR FOR PM 2124 AL ALLOYS, *D. J. Chellman. Lockheed-California Co .• Burbank. CA 91520 and H. G. Paris. Alcoa Technical Center. Alcoa Center. PA 15069 Significant improvements in the combination of strength and fracture toughness have been recently demonstrated for PM 2124 Al alloy e::trusions. This class of PM Al alloys was designed to meet durability and damage tolerant requirements as well as elevated temperature service to 350°F. The present work addresses the notched fatigue and fatigue crack growth behavior to two PM 2124 Al alloy compositions involving Zr additions. Various testing conditions were employed in the evaluation of the heat treatment extrusions. The experimental results were compared to a baseline 1M 2124 Al alloy extrusion in addition to previous work on 8 NASA funded program. Constant amplitUde fatigue life of the PM 2124 Al alloys was greater than the 1M counterpart for Kt =2. 7 specimens. In contrast to PM 7XXX Al results. the fatigue crack: growth behavior was Similar for the PM Al alloys above 5.0 x 10- 7 in./cycle. Differences in the alloy microstructures were employed to interpret the observed property results. I

EFFECT OF DYNAMIC STRAIN AGING ON MECHANICAL AND FRACTURE PROPERTIES OF IRRADIATED FERRITlC Dirk J. Oh and K. Linga Murty, N. ~:E~~~t: u~~~~r~it~~n~aleigh, N.C. 27695-7909.

~~~~~r!a~ 1d~~~~6~ili;dw~~d I ~~~di!~~aego~di ~I;~s s ~~e !x!~i~~e the effects of interactions between interstitial impurities and radiation induced defects. Both the lower yield stress and

~~g~r ~ l ~~~~ ;gn all ~~~~e :emK~r~~~~~r!~~i~~ s~go~! n~g6~f 3~§Q. c ~~~ ld

stress did not always increase wlth fluence due to the intervention of dynamiC straln aging. With intreasing fluence, the degree of locking of the dislocatlons by interstitials decreased, the critical temperature for dynamiC strain aging increased and the temperature range of jerky flow narrowed. It is shown here that

~g:n e ~~d~~t i~n d~~b~t~ t i~~:~~ ~~~~y t ~~g d~~t t~~;~a~~d m~I: lde~~~:ngth as well as ductility at elevated temperatures following radiation exposure. Limited "amount of data collected to date on A533B class 1 pressure vessel steel material revealed unstable flow at elevated temperatures. The impact of these results on synergistiC effects of dynamic strain aging and radiation-induced defects on radiation embrittlement of nuclear pressure vessel steels and pressurized thermal shock phenomena (PTS) will be discussed.

*Research sponsored by NASA-LaRC Program on High Temperature

Al Alloys.

(11:40 a.m.) RAPIDLY SOLIDIFIED Al-Fe-Mo AND Al-Be ALLOYS: R.D. Field, J.W. Zindel, D.C. VanAken and H.L. Fraser, Dept. of Metallurgy and the Materials Research Laboratory, Univ. of Illinois, Urbana, IL.

(10:30 a.m.) THE PWR PRESSURIZED THERMAL-SHOCK IS5UE,* R. D. Cheverton, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831

Rapidly solidified alloys of Al-9Fe-2Mo and Al-2.5B (wt%) have been produced by melt-spinning in He. Microstructures in both alloys have been characterized using analytical electron microscopy. The Al-Fe-Mo alloy displays a refined cellular mi crost ructure wi th fi ne part i cl es of i ntermeta 11 i c phase in the intercellular regions. The Al-Be alloy possesses a refined dispersion of Be precipitates in an a-Al matrix. Ribbon which has been reduced to particulate by rotating knives may be extruded at 350°C to form bul k specimens from whi ch test specimens are taken. Results from mechanical testing both at room temperature and 350°C' will be p resented and di scussed in re 1at i on to the compacted mi crostructu re.

In recent years there has been concern that a specific category of postulated transients might challenge the integrity of PWR pressure vessels. If sharp, crack-l ike defects exist on the inner surface of the vessel, in a region where the radiation-induced reduction in fracture toughness is high (opposite the core), the combined pressure and thermal loadings might result in extensive propagation of the flaws during such transients. The occurrence of several pressurized thermal-shock (PTS) transients and a growing awareness that the radiation damage rate in the reactor vessel is perhaps greater than previously expected prompted the Nuclear Regulatory Commission (NRC) and the nuclear industry in 1980 to intensify their studies of the PTS issue. These studies include the development and validation of fracturemechanics methods of analysis for reactor pressure vessels, the measurement of material properties associated therewith, postulation of PTS transients for specific plants, and estimates of the frequency of vessel failure. A number of remedial measures, such as changing the design of the fuel loading to reduce the radiation damage rate, have been imp I emented. . . *Research sponsored by the U.S. Nuclear Regulatory CommiSSion.

MECHANICAL FAILURE MODES IN NUCLEAR MATERIALS I: Analysis and Experience Sponsored by the TMS-ASM-MSD Nuclear Metallurgy Committee Tuesday, February 26, 1985 8:30 a.m.

Monarch Suite Sheraton Centre

Session Chairmen: J. C. Bilello, Department of Materials Science, State University of New York, Stony Brook, NY 11794; J. R. Weeks, Department of Nuclear Energy, Brookhaven National Laboratory, Upton, New York 11973 (8:30 a.m.) FRACTURE MECHANICS-APPLICATION TO MATERIALS USED IN THE NUCLEAR INDUSTRY: Stephen D. Antolovich, Director, Fracture and Fatigue Research Laboratory, Georgia Institute of Technology, Atlanta, Georgia 30332-0100 Materials used in the nuclear industry are generally characterized by moderate strength along with high ductility and high toughness. Typical examples are 304 and 316 stainless steels, 2 1/4Cr-IMo and 9Cr-IMo steels as well as some F e-Ni base alloys such as IN 718. These materiqls are used in wrought and welded conditions and are subjected to moderate temperatures and cyclic loads, including thermomechanical cycling. Analytical formalisms used to characterize fracture, creep, and creep/fatigue interactions will be reviewed. Included will be LEFM, J intearal and C approaches. Their ranges of applicability will be defined and -life prediction models using these methods and incorporating microstructural effects will be presented~

(11:15 a.m.) MECHANICAL FAILURE OF THE VENT HEADER CRACK AT EDWIN I. HATCH UNIT #2:* Carl J. Czajkowski, Brookhaven National Laboratory, Department of Nuclear Energy, Upton, New York 11973

A metallurgical failure analysis was performed on pieces of the cracked vent header pipe from the Edwin I. Hatch Unit #2 Nuclear Power Plant. The general conclusions drawn were: 1) the material of the vent header met the mechanical and chemical properties of ASTM A516 Gr. 70 material and the microstructures were also consistent with this material; 2) the fracture faces of the cracked pipe were predominantly brittle in appearance with no evidence of fatigue contributIon; 3) the NOH (Nil Ductility Transition Temperature) for this material is approximately -60°; and 4) these observations suggest that an impingement of low tempe rature nit rogen (caused by a fau 1ty torus inert i ng sys tern) induced a thermal shock In the pipe which, when cooled below its NOTT, cracked in a brittle manner. *Research sponsored by the U.S. Nuclear Regulatory Commission, Region II.

40 - TMS-AIME Annual Meeting Program METALLURGY OF JOINING OF MATERIALS III Sponsored by TMS Physical Metallurgy and Solidification Committees Tuesday, February 26, 1985 8:30 a.m.

Washington Suite Sheraton City Squire

Session Chairman: John Perepezko, Univ. of Wisconsin· Madison, Madison, WI 53706

(8:30 a.m.) MICROSTRUCTURAL TRANSFORMATIONS IN RAPIDLY SOLIDIFIED Cu-Mn-SiBASE ALLOYS USED AS FILLER METALS: A. Rabinkin, F. Reidinger and J. Marti, Allied Corporation, Morristown, NJ 07960.

A family of new alloys based on the Cu-Mn-Si ternary eutectic was recently developed as general purpose brazing filler metals. The alloys also contain, small additions of silver, indium, tin and zinc. These alloys are produced as due tile ribbons by rapid solidification (RS) technique analogous to that of amorphous metals. It is shown by means of STEM and X-ray diffraction analysis that RS results in a microstructure with submicron grain size. The matrix is either a metastable b.c.c. a-bronze or a 9R martensite: In both cases small ("'0.1 ~m) crystals of the MnSSi3 phase are randomly distributed in the matrix. The appearance of martensite in the copper-base alloys after RS is observed for the first time. The quenched a-phase isothermally transforms into 9R martensite after a few weeks at room temperature. During heating of the as-cast ribbons, the B-phase first transforms near 120°C into the 9R martensite which subsequently, near 300°C, decomposes into a copper-base f. c. c. phase and MnsS13 crystals of increased size. Specifics of the microstructure of steel to steel joints brazed with the new Cu-Mn-Si base and conventional silver-base alloys are also examined.

(10:45 a.m.) AN INVESTIGATION OF THE WELD HEAT-AFFECTED ZONE TOUGHNESS OF A NINE PERCENT NICKEL STEEL: John P. Balaguer, Rensselaer Polytechnic Institute, Troy, New York 12181.

The weld heat-affected zone toughness of nine percent nickel steel weldments at cryogenic temperatures was investigated. The material was thermally treated using a Gleeble to produce syn":' thetic weld heat-affected zones. Toughness of this steel, subj ec ted' to three different thermal cycles, was measured using the Charpy V-notch impact test. It was found that the material subjected to severe thermal cycling still met the ASTM toughness requirements for this steel at liquid nitrogen temperatures. The upper shelf energy for this steel was lowest for an intermediate thermal cycle of lOOO°C peak temperature. The retained austenite content of this material, under varying conditions of thermal treatment, was determined using standard X-ray diffraction techniques. It was found that toughness increased as the amount of retained austenite increased. Retained austenite was also measured using the Magne-Gage, and these data were correlated with the X-ray diffraction results.

MODELING IN PROCESS METALLURGY II: HEAT TRANSFER Sponsored by the TMS Physical Chemistry Committee and the PTDI/SS Tuesday, February 26, 1985 8:30 a.m.

Dominion A Sheraton Centre

Session Chairmen: D. Apelian, Dept. of Materials Engr., Drexel V., Philadelphia, PA 19104; H. Henein, Dept. of Metallurgical Engr. and Materials Science, Carnegie-Mellon V., Pittsburgh, PA 15213 (8:30 a.m.)

(9: 00 a.C1.) JOINING OF plM Al-3Li-BASED ALLOYS:* R. J. Lederich, P. J. Heschter, and J. E. O'Neal, McDonnell Douglas Research Laboratories, St. Louis, MO 63166.

The diffusion kinetics of eutectic bonding of rapid-solidification-processed AI-3Li alloys were investigated. Surfaces to be joined were cleaned by argon ion milling and' coated with a - 0.5 ).lm thick Cu layer. The coated surfaces were placed in contact. heated above the AI-Cu eutectic temperature (547°C), and isothermally bonded for varying time periods. Microstructural development during bonding was followed by optical and scanning electron microscopy and energy dispersive x-ray analysis, and interpreted on the basis of formation and decomposition of a thin eutectic liquid layer at the bond interface. Bond integrity was evaluated by lap-shear mechanical testing, and bondability of Al-Li alloys by this method was demonstrated. *Research conducted under the McDonnell Douglas Independent Research and Development program.

(9:30 a.m.) TEMPERATURE DEPENDENT MECHANICAL PROPERTY MODELING OF 1. C. DEVICE SOLDER CONNECTIONS: M. A. Burke, W. J. Reichenecker and D. G. Thompson, Westinghouse R&D Center, Pittsburgh, PA.

The isothermal stress-strain and stress relaxation data for continuous and hold time cycling of 63-37 solder alloy have been generated at -55°C, room temperature and l05°C. The deformation behavior at the three temperatures has been compared and the effect of including the temperature variation of mechanical properties upon the finite element modeling of solder interconnectors in Ie assemblies will be discussed.

(10:00 a.m.)

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(10: 15 a.m.) THE WELDING METALLURGY OF 12Cr-1Mo STEELS: J. C. Lippold, Sandia National Laboratories, Livermore, CA 94550.

The l2Cr-lMo steels are a class of martensitic stainless steels which have become increasingly popular as a replacement for aus teni tic stainless steels. While mechanical properties of the l2Cr-lMo steels are at least comparable to the austenitics, the weldability of these steels is generally considered to be inferior due to the preheat and postweld heat treatments which must be performed. During fusion welding of these steels, the fusion zone and portions of the heat-affected zone form untempered martensite. In addition, a small amount of delta ferrite is usually present along solidification boundaries in the fusion zone and at prior austenite grain boundaries in the adjacent HAZ. Both the untempered martensite and the residual delta ferrite significantly influence the properties of the weld region. The effect of postweld heat treatment on the various weld regions will be discussed in detail. Both the SEM and the STEM have been used to study the fracture and transformation behavior, respectively.

A Model of RST Using the Single Roll Technique E. Gutierrez and J. Szekely, Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139

Through the statement of the laminar Navier-Stokes equations and the differential thermal energy balance equation a mathematical model has been developed to describe heat and fluid flow phenomena in the single roll rapid solidification process. The meniscus formed is predicted from first principles and the theoretically predicted ribbon thickness is in good agreement wi th measurements.

(9:00 a.m.)

HEAT TRANSFERTO SUBMERGED LANCES INJECTING GAS AND PARTICLES", G.A. Irons, McMaster University, Hamilton, Ontario CANADA Experiments were conducted in which nitrogen and sil ica (30, 130 and 450 ).IIl1 diameter) were injected into liquid lead through a submerged lance instrumented wi th 4 thermocoup1 es. Ana1ysi s of the data provided heat transfer coefficients for the inner and outer surfaces of the lance in both bubbling and jetting flow regimes. These coeffi c i ents were in reasonable agreement wi th theoretically calculated ones. A two-phase model to calculate gas and particle velocities and temperatures as they move down the lance was developed. The heating of the particles was only a few degrees, yet because of the high solids loading this is a substantial heat demand which can cause lance plugging. (9:30 a.m.)

RIBBON FORMATION DURING MELT SPINNING, V. Laxmanan, Department of Metallurgy and Materials Science, Case Western Reserve University, Cleveland, Ohio 44106.* In two previous papers* a simple model for ribbon formation duri ng melt spinning of crysta 11 i ne alloys (based on uni di rectiona1 heat flow analysis) was presented by the author. Both these papers assumed "ideal" cooling, that is, an infinite heat transfer coefficient between the substrate and the melt puddle. However, the heat flow problem was rigorously correlated with the results obtained from dendritic solidification theory. This paper will consider the influence of a finite heat transfer coeffi ci ent on the predi cted va 1ues of ri bbon thi ckness, ri bbon surface temperature and wfiee1 surface temperature. * AIME Annual Meeting, Feb. 1984; Fall Meeting, Sept. 1984. (10:00 a.m.)

Sreak

(10:15 a.m.) Plasma-Mel t Interactions in Plasma Furnaces G. Backer, J. McKelliget and J. Szekely, Department of Materials Science and Engineering, MassachUsetts Institute of Technology, Cambirdge, MA 02139 A mathematical model has been developed to represent two dimensional axy-syrrunetric heat and fluid flow in plasma jets impinging onto solid and molten metal surface. The theoretical predictions are compared with measurements obtained in a 50kW plasma furnace.

TMS-AIME Annual Meeting Program - 41 (10:45 a.m.)

(9:40a.m.)

WIRE FEEOING PROCESSES IN STEELMAKING:*: Frank Mucciardi, Enzo Palumbo, McGill Unfversity, Montreal, P.Q., Canada, H3A 2A7. Both analytical and empirical analyses of three of the most important \.ire feeding systems will be presented. These systems comprise the feeding of aluminum, calciUm, magnesium and alloys thereof. It will be shown that the depth of penetration of an aluminum wire is directly proportional to its diameter and velocity and inversely proportional to the melt superheat. Moreover, a mathematical model that simulates the heat transfer during the feeding of an aluminum wire will be described. In terms of the addition of volatile reagents such as calcium and magnesium, powder injection techniques are currently used to a much greater extent than wire feeding. One of the reasons for this is that researchers have been unable to develop suitable wires that are both economical and efficient. Moreover, to be competitive such wires would have to minimize fume generation as well as pyrotechnics. Our findings indicate that wire feeding techniques for volatile reagents can be successful if the mass {low raye of the reagent and the velocity of the wire are d~~~~~gea?'. A technique by which this can be achieved will be

CHARACTERIZATION OF CARBON-FIBER/ALUMINUM COMPOSITES BY SURFACE SPECTROSCOPIES. R. N. Lee. F. Santiago and M. K. Norr. Naval Surface Weapons Center. Whi te Oak. S11 ver Spri ng. MD 20910 It is generally recognized that many mechanical properties of C/Al Composites depend critically on the composition and atomic distribution on and around the carbon fibers. The presence of oxygen and the segregati on of a1umi num alloy components in an interphase region between the fiber and matrix are known to be of particular importance to the mechanical properties. Analysis of the interphase region shows it to be a mixed phase of oxides and metal rather than purely spinel. Moreover, a significant amount of chI ori ne is found in the compos ite. The impl i cati ons for mechanical properties, corrosion resistance and the eva 1uati on of compos i te wi re wi 11 be di scussed. (10:00 a.m.)

Break

(10:30 a.m.) 113E OF ROBOTIC TECHNIQUES IN NDE OF METAL MATRIX CO~IPOOITES, R. A, BLAKE AND R. B. PIPES, CENTER FOR COMPOSITE MATERIALS, 'iiiiIVERS"iT'iOF DELAWARE., NEWARK, DE 19716.

NONDESTRUCTIVE EVALUATION IN METAL MATRIX COMPOSITES Sponsored by the Jt. TMSIASM-MSD Composites Committee Tuesday, February 26, 1985 8:30 a.m.

Province ~oom Sheraton Centre

Aspects of metal matrix composite material inspection are presented with emphasis toward the solution of inspection difficulties through robotic techniques. Dynamic focusing and innovative scanning methods are presented for depth of field 1 improvement along with image enhancement procedures which aid the observer in the detection and recognition of flaws wi thin the material.

(10:50 a.m.) DETECTION OF FAILURE MODES IN BORONI ALUMINUJl MONOLAYER THROUGH ACOUSTIC EMISSION.

Session Chairmen: S. G. Fishman. Office of Naval Research. Arlington. VA 22217 (8:30 a.m.)

M. Madhukar and J. Awerbuch Department of Mechanical Engineering and Mechanics Drexel University Philadelphia. Pennsylvania 19104

Introduction

(8:40 a.m.) NONDESTRUCTIVE TESTING OF SiC/AI and Gr/Al, C. W. Anderson. Naval Surface Weapons Center, Silver Spring, MD Potential material defects for both SiC/AI and Gr/Al are reviewed along with the capabil ities and 1imitations of nondestructive methods for defect detection. In SiC/AI the primary concerns address the detection of porosity and poor blending of constituents. Such defects can be detected in simple shapes by a combination of ultrasonic attenuation, ultrasonic velocity and eddy current testing. Defects of concern in Gr/Al include poor infiltration, incomplete consolidation. and elastic modulus variations. Specialized radiographic, ultrasonic velocity and eddy current test methods have been developed to detect such anomalies in Gr/Al. In all instances the specific geometry of the item under test is the most significant factor in the successful appl ication of nondestructive testing technology.

. X-RAY TECHNIQUES FOR QUALITY ASSURANCE OF METAL MATRIX WIRES:

(9:00 a.m.)

E. P. Munt%, J. R. Linn and G. F. HaWkins, The Aerospace Corp., P.O. Box 92957, Los Angeles, cA 90009. An X-ray technique has been developed which can detect voids and composi ti on changes in metal matri x wi res. The techni que util izes a liquid which has the same X-ray absorbtion characteristics as that of the wire. The wire is x-rayed while it passes through a cell filled with the liquid. This completely cancels any diameter changes in the wire. The signal from the X-ray detector is constant unless a void is present in the wire. Calibration techniques and typical data will be presented. *Th1 s work was supported by the Naval Surface Weapons

This study concentrates on monitoring damage initiation and progression through acoustic emission in boron/aluminum laminates subjected to quasi-static tensile loading. Emphasis is placed on detection and identification of the major failure mechanisms associated with failure of boron/aluminum composites: fiber breakage. matrix plastic deformation and interfacial failure. Acoustic emission source intensity Signatures such as amplitude, energy, duration, rise-time, frequency spectrum, and counts per event are analyzed for [0]. [90], and [45] monolayers as well as for [0/90]2s and [±45l2s laminates and constituents (fiber and matrix) • ·work sponsored by the Air Force Office of Scientific Research

(11 :10 a.m.) CHARACTERIZATION OF SiC PARTICLES REINFORCED ALUMINUM COMPOSITES

BY SURFACE ACOUSTIC WAVES, John M. Liu, Materials Evaluation Branch (R34), Naval Surface Weapons Center, Silver Spring, MD 20910 It is k.nown that SiC particles reinforced aluminum composites exhibi t many of the deformation characteristics of conventional aluminum alloys. We have applied ultrasonic wave propagation techniques for the measurement of the elastic and plastic behavior of these composites at a number of deformation stages along their stress-strain curves. In order to facilitate an interpretation of the measured ultrasonic wave velocity changes by means of the elastic and plastic deformation characteristics in these composites, we have developed non-contact electromagnetic acoustic transducers, generating and receiving acoustic surface waves. OUr techniques should be useful for investigating cracks and deformation structures originating from the surface on these composites.

Center (11:30 a.m.)

(9:20 a.m.) UL'lWISCNIC NIlE (F METAL MA'nUX PLATES AND 'ruBE'S BY USE (F LI\MB

WAVES: Robert W. Reed, United Technologies Research Center, East Hartford, cr. The acceptance of Jl'etal matr ix composites (!!MCs) for cr i tical applications requires the developnent of NIlE methods capable of not only detecting defects but also assessing constitutive material properties. Ultrasonic Lamb waves are used to evaluate the structural integrety and elastic moduli of metal matrix composite (MMe) plates and tubes. The lowest order aymJl'etric mode Lamb waves are generated and received by electromagnetic acoustic transducers (E2!ATs). Novel signal processing techniques are used to provide accurate velocity and attenuation values independent of transducer lift-off variations. The attenuation data, obtained by non-contact scanning of an E2!AT array, are ussful for defect detection. The velocity data are used to determine values of elastiC moduli. Representative data are presented for unidirectional and crossply graphite/aluminum !!MC plates and tubes. Resulting modul i are canpared to those obtained by mechanical Jl'eans.

NONDESTRUCTIVE EVALUATION OF METAL MATRIX COMPOOITES II: Scott W. Schramm, Jane W. Adams, lIT Research Institute, Chicago, I~

b1i6i:6."

The objective of the investigation was to apply nondestructive evaluation (NDE) methods to identify potentially harmful casting defects in FP/magnesium composites; establish detectability and reproducabili ty limits of NDE applied to FP /magnesi um composites; and establish relationships between casting defects and failure modes of FP/magnesium composites. The material investigated was ZE4lA magnesium alloy reinforced with FP (aluminum oxide) fibers. Twenty-seven coupons (four coupons of each of five flaw types and seven miscellaneous coupons) were evaluated using ultrasonic scanning, wave propagation velocity, and wave attenuation inspection techniques. After the detectabili ty and reproducability NDE inspections were completed, tensile and/or bend specimens were machined from the parent coupons, strain gaged, and statically loaded to failure. Hicrographs were made of the fracture surfaces for comparison with the NDE records. It was found that ultrasonic scanning using a 20 MHz compression wave focused transducer operated in the pulse-echo mode generating an analog C-Scan proVided 100% detectabili ty and reproducabili ty of the intentionally flawed coupons.

42 - TMS-AIME Annual Meeting Program OTHER LIGHT METALS Sponsored by The TMS Light Metals Committee Tuesday, February 26, 1985 8:30 a.m.

Georgian Ballroom B Sheraton Centre

Session Chairmen: S. K. Das, Arco Metals Co., 2700 First National Tower, P.O. Box 32860, Louisville, Kentucky 40232; J. C. Agarwal. Amax Metals Group, P.O. Box 1700, Greenwich, Connecticut 06836

(8:30 a.m.) "MAGNES[UM - rTS STATUS AND FUTURE OUTLOOK" - Dr. A. H. Schultz and Dr. R. Neelameggham, AMAX MagneSltJT1 Corporatlon, 238 North 2200 West, Salt Lake City, UT 84116 and Dr. J. C. Agarwal, AMAX Metal S Group, AMAX Center, Greenwich, CT 06836 An overview of the magnesium industry is presented as regards historical constJT1ption/production data. The present situation is reviewed while the outlook for the future of this versatile metal is forecast. Areas of emerging growth are presented as is its relationship with aluminum. (9:00 a.m.)

PHASE DIAGRAMS, ALLOY PHASE STABILITY AND THERMODYNAMIC ASPECTS OF NOBLE METAL ALLOYS III: Thermodynamic Aspects Co-sponsored by TMS Committee on Alloy Phases, ASM Alloy Phase Diagram Data Committee and ASM-MSD Thermodynamics Committee Tuesday, February 26, 1985 8:30 a.m.

Versailles Terrace Sheraton Centre

Session Chairman: J. D. Livingston, Corporate Research and Development, General Electric Company, Schenectady, NY 12301

(8:30 a.m.)

MAGNESIUM BY THE MAGNETHERM PROCESS -

FUSED SALT REFINING:

determine the effect of certain variables on the sulfation rate. Results show that the sulfation rate improved with increased acidity, temperature, and agitation. as well as with decreased particle size and percent solids. Under some conditions, over 98 pct of the titanium was rapidly converted to water-soluble sulfates. These observations suggest that acid sulfation can provide a feasible first step in processing perovskite concentrates.

PROCESS CONTAMINATION AND

Kenneth A. Bowman, ALUMINUM COMPANY OF

AMERICA, Smelting Process Development Division, Alcoa Technical Center, Alcoa Center, PA

15069

The crude magnesium produced by the Magnetherm Process must be refined to make a commercial product. Samples of the crude product taken before and during the refining step were analyzed by X-ray fluorescence and by scanning electron microprobe. The main impurities are oxide inclusions containing varying combinations of magnesium, aluminum, calcium and silicon. Additionally, aluminum, calcium and silicon are found as metallic impurities dissolved in the magnesium. The contamination sources have been identified as raw materials fed to the reduction furnace, the process slag and products of undesirable side reactions. These are entrained in the magnesium vapor stream transporting from the reduction furnace to the condenser. A major source of MgO contamination appears to be oxidation of the magnesium product prior to refining. Fused salt refining is shown to successfully produce commercial purity magnesium.

(9:30 a.m.) SURVEY OF LITHIUN RESOURCES - WORLDWIDE: * Jack S. Whisnant and James B. Holman. Lithium Corporation of America, Bessemer City, North Carolina 28016

SYSTEMATIC ASPECTS OF THE THERMODYNAMICS OF LIQUID ALLOYS OF NOBLE METALS AND TRANSITION METALS: O. J. Kleppa and Letitia Topor, James Franck Institute and Department of Chemistry, University of Chicago, Chicago, Illinois 60637. A review is presented of thennochemical data recently obtained in our laboratory for two different families of liquid alloys: (1) the binaries formed among the noble metals copper, silver. and gold; (2) the liquid solutions of first row transition metals in copper and gold. The results are compared with predictions derived from the semi-empirical model of Miedema et ale For both families of alloys comparisons between the 'new enthalpy data and excess Gibbs energies reported in equilibrium or e.m.f. studies provide new insight regarding the excess entropy of mixing.

(9:20 a.m.) PHASE RELATIONSHIPS AND STABILITIES OF THE a, THE 8 AND VARIOUS MARTENSITIC PHASES IN BRASSES. M. Ahlers, Centro Atomico Bariloche, 8400 Rio Negro, Argent1na. Starting from the long range ordered bcc 8 1 phase it is possible

to obtain by a martensi tic transformation various close packed phases. From the temperatures or from the applied stresses at which the phase changes occur, it is possible to determine

experimentally the enthalpy and entropy difference between the

corresponding phases and compare them with theoretical models. From a preceived shortage of lithium resources as recently as a decade ago, and perhaps partly as a result of those preceptions, it now appears that a more immediate problem is a shortage of markets. Within the last decade several new lithium-bearing pegmatites have been discovered. drilled and/or brought into production. Clay resources have been explored and the basic. extractive metallurgical work done. One major brine resource has been brought into production, and the development of another is foreseen. These and other efforts have advanced down the time axis the conversion of resources both to and toward a reserve status. Sufficient resources (from a world or domestic perspective) exist to meet the high-side estimates of projected ,demand for all foreseeable uses. The location, status and estimated quantities of lithium for these resources are reviewed.

For single crystal of Cu - Zn and Cu - Zn - Al alloys of adequate compositions it is possible to obtain an 18R, fct and hex single

crystal. starting from one sample of a B phase single crystal. For this reason these alloys have been studied in some detail. The experimental results concerning the enthalpy and entropy differences are presented. They are analyzed in terms of the nearly free electron contribution, the configurational contribution to be described by pair interchange energies, and tbe vibrational component. The results are then applied to the discussion of the a and 8 equilibrium phases.

(10:10 a.m.) ELECTRONIC AND STRUCTURAL DISORDER IN INTERMETALLIC COMPOUNDS OF Ca, Na, AND K WITH Au.* R. Alqasmi and J. J. Egan, Brookhaven National Laboratory, Upton, New York 11973.

(10:00 a.m.) LITHIUN RECOVERY FROM VARIOUS RESOURCES: Robert J. Cinq-Mars, Lithium Corporation of America, P. O. Box 795, Bessemer City. North Carolina 28016. There are many natural resources for lithium. The processes to recover lithium are very dependent on the type of natural resource. The variety of types of resources and the accompanying mineralogy determine the degree of difficulty of the extraction process. This paper will review the basic flow sheets. unit operations and raw materials for commercial and proposed processes to recover lithium from known pegmatites, geothermal brines, evaporites and clays.

(10:30 a.m.) TITANIUM RECOVERY FROM PEROVSKITE: M. B. Shirts, L. J Froisland, A. E. Petersen, and D. K. Steele, Salt Lake City Research Center, Bureau of Mines, U.S. Department of the Interior, 729 Arapeen Drive, Salt Lake City, UT. Domestic perovskite (CaO·Ti02) ores represent a Significant unutilized titanium resource. The Bureau of Mines investigated sulfuric acid-perovskite concentrate reactions as a method of converting the titanium to water-soluble sulfates. Batch studies were conducted in an agi tatar-equipped gla~s vessel to

Thermodyn8.LDic Illeasurements using a coulometric t1 tration technique with CaF2 solid electrolytes were Illade on the binary alloy systems Na-Au, K-Au, and Ca-Au. Results giving the range of homogeneity and Gibbs energy of forlllation for several interlnetallic compounds in these systems are reported. The therLllodynalllic results combined with appropriate atomic models yield the type and degree of disorder for the coaapounds NaAu5, NaAu2, KAuS, KAu2, KAu, CaAUSI Ca2Au9, C8ZAu7, and CaAu20

*This work was supported by the Division 'of Chemical Sciences, U.S. Department of Energy, under Contract No. DE-AC02-76CH00016.

(11:00 a.m.) A THERMODYNAMIC DESCRIPTION OF TERNARY Fe-Cu-Ni AND A CALCULATION OF SP[NODALLY DECOMPOSED STRUCTURES: Ying-Yu Chuang, R. Schmid' and Y. Austin Chang, Dept. of Metallurgical and Mineral Engrg .. Univ. of I~isconsin-Madison, Madison, WI 53706 An equation is proposed to calculate the thermodynamic properties of the 1 iquid and fcc phases in Fe-Cu-Ni from those of the three binaries. The fcc-L equilibrium and the fcc miscibility gap

TMS-AIME Annual Meeting Program - 43 calculated from these thermodynamic properties agree well with data available in the literature. Based on the thermodynamic properties of the fcc phase, the stabil ity of the system with respect to infinitesimal composition fluctuations is described. The easiest direction for compositional fluctuation is defined by the one with the largest negative curvature of the Gibbs energy surface. Along this direction, zero-time wavelength at initial stage of spinodally decomposed alloy structure may be cal cu1 ated. 'Now with Technical University, Clausthal-Zellerfeld, Germany

PHYSICAL METALLURGY OF ELECTRICAL STEELS I Sponsored by the TMS Ferrous Metallurgy Committee Tuesday, February 26, 1985 8:30 a.m.

Consulate Suite Sheraton Centre

Session Chairman: E. T. Stephenson, Research Department, Bethlehem Steel Corp., Bethlehem, PA 18016 (8:30 a.m.) CHARACTERIZATION srUDIES OF HIGH SILICON NONORIENrED ELECTRICAL SHEEl': R. R. Judd and H. Hu, U. S. Steel Corporation, Technical Center, Monroeville, PA. A characterization study of nonoriented, rv3 percent silicon steel during its commercial processing has been conducted. The microstructure and texture of the steel at various stages of the processing treatments from hot band to O.OlB-inch-thick annealed sheet were closely examined. Moreover, the effects of normalizing hot-rolled band, in the range of 1650 to 1800°F (899 to 982°C), on the microstructure and crystallographic texture of the hot band, the cold-rolled and annealed sheet, and on the magnetic properties of the annealed sheet were also studied. The relative prominence of the texture components, [001] <130) and [554 J <225>, of the annealed sheet is expected to be influential to its magnetic properties.

(9:00 a.m.) THE EFFECT OF ABSOLlITE SULFUR CONTENT AND MANGANESE TO SULFUR RATIO ON THE MAGNETIC PROPERTIES OF COLD ROLLED LAMINATION STEELS: K. C. Liao, R&D Dept., National Steel Corp., Weirton, WV. The effect of absolute S content and MntS ratio on the magnetic performance of cold rolled lamination steel was investigated in eleven low C steels. The test results indicated that MntS ratio rather than the absolute S content was the dominant factor influencing the core loss when the MntS ratio was below a certain range. At higher MntS ratios, the effect of the MntS ratio was greatly reduced and in turn the absolute S content was the major factor. The influence of the absolute S content and the MntS ratio on the permeability was not as well defined as that observed for the core loss. The permeability was seen to be affected mainly by the Mn content. An optimum range of Mn was a prerequisite for optimum permeability. (9:30 a.m.) THE EFFECT OF THERMOMECHANICAL HISTORY UPON THE MICROSTRUCTURE AND MAGNETIC PROPERTIES OF NON-ORIENTED SILICON STEELS: G. Lyudkovsky and P. D. Southwick, Inland Steel ResearCli' Lilioratones East Chicago, IN 46312

A study has been conducted to evaluate the effect ·of the hot rolling conditions on the precipitation behavior of MnS and A1N, on the microstructure, texture and, subsequently, magnetic properties of non-oriented sil icon steels. TEM work showed that MnS particles act as nucleating sites for dissolved A1N by providing an interface on which to precipitate. It was established that for the steels studied decrease in reheat and a correspon.ding increase in coiling temperature results in better texture and subsequently better magnetic properties of the fihal product. These phenanena were exp1 a ined based on the effect of steel composition and heat roll ing history on the recrystallization behavior in the hot band and continuously annealed strip. Regression equations relating magnetic properties to hot roll ing parameters were developed. (10:00 a.m.) FACTORS AFFECTING THE FINAL GRAIN SIZE OF DECARBURIZED LAMINATION STEELS: A.R. Marder, Research Department, Bethlehem Steel Corp., Bethlehem, PA 18016. A study was made of the effects of carbon content, strain, initial grain size, carbide morphology, annealing time and temperature on the final grain size produced after the decarburization anneal. The results show that columnar grains only form in higher carbon (0.05/0.06% C) steels with low initial grain sizes «20 \.lm) when decarburized at 1450 Q F (788°C). Equiaxed grains, however, are obtained in low carbon (0.02/0.03% C) lamination steels for all processing conditions. It was found that the formation of both equiaxed and columnar

final grain size (GS f ) was dependent upon percent strain (£). initial grain size (GS.). and carbide distribution (D ) according to the follo,}ing regression equations (all ~rain size measurements in urn): GSf(columnar grain) = 204+0.9GS .-12.3£+37.S D 10gGSf(equiaxed grain) = 2.1S1+0.02 GS.-O.03S c £-O.0005GS .. £ -O.0002(GS i ) +O~079Dc 1

2

(10:30 a.m.)

A STUDY ON TEXTURE, PROPERTIES AND FORMING MECHANISM OF DECARBURIZED COLUMNAR GRAIH IN ELECTRICAL STEEL He Li-jum, Fei Da-rum and Liu Pu-ru, Silicon Steel Plant of WISCO, Wuhan, China. The SiliCOn-free electrical steel sheet containing phosphorus presents a coarser decarburized columnar grain with a larger amount of (lkO) texture, so that, an excellent properties of product with B50 =1.8T, P15/50=4.5W/Kg, soft and somewhat brittle ln its mechanical properties can be achieved. The necessary condition for forming the decarburized columnar grain is diffusion of carbon accompanied by a phase change in one dimension. The sufficient condition is that the migration rate of the grain boundary VB is higher than the growth rate of the decarburized layer VD. In this paper the effect of compositions, annealing temperature and atmosphere for decarburizing and original state are discussed. (11:00a.m.) KINETICS OF CEMENTITE A,'ID E-CARBIDE PRECIPITATION IN SILICON

STEELS. C.M. Michal, Department of Metallurgy and Materials Science, Case Western Reserve University, Cleveland, Ohio 44106 and J. A. Slane, Republic Steel Corp. Research Center, Independence, Ohio 44131. The kinetics of carbide precipitation in a fully processed 2.3 wt. % silicon electrical steel with carbon contents of 0.016 to 0.004

wt.% were investigated over the temperature range from room temperature to 750°C. The size, morphology and distribution of the carbide phases as a function of aging time and temperature, were determined by combined optical and transmission electron microscopy techniques. The 1.5 T core loss was also evaluated and correlated with the changes in precipitation. Distinct C curves were observed for the formation of grain boundary cementite at temperatures above 400°C and s-carbide at temperatures be1crw 300°C. Grain boundary cementite had a relatively small effect on core loss. The large increases in core loss that accompanied s-carbide precipitation maximized a~ specific aging times and temperatures depending on the carbon content of the steel. The influence of silicon on carbide preCipitation is discussed.

(11 :30 a.m.) GRAIN GROWTH AND MAGNETIC PROPERTIES OF RAPIDLY QUENCHED SILICON STEEL RIBBONS: K. 1. Arai and K. Ohmori, Research Institute of Electrica 1 Communication, Tohoku Uni versi ty, Sendai 980, Japan

Grain growth, grain texture and soft magnetic properties of 6.5 mass% silicon-iron ribbons prepared by a rapidly quenched roller method were observed, when the ribbons were annealed at high temperatures in a vacuum atmosphere. When the annea 1 ing temperature was around 973K, the primary recrystal1 ization was found near the middle part of the ribbon thickness, and the grain size increased with increasing the annealing temperature. When the ribbons were annealed at 1373K, the grains whose (l00) planes were parallel to' the ri bhon surfaces grew, and all ri hbion surfaces were covered with these grains after 1 hour anneal ing. When the annealing temperature was kept above 1473K, the grain with (110) plane grew and all ribbon surfaces became parallel to (110) plane.

POWDER METALLURGY OF REFRACTORY METALS Sponsored by the TMS Refractory Metals Committee Tuesday, February 26, 1985 8:30 a.m.

Commonwealth Room Sheraton Centre

Session Chairman: C. C. Wojcik, Teledyne Wah Chang Albany, P.O. Box 460, Albany, OR 97321

(8:30 a.m.) CONSOLIDATION OF MOLYBDENUM POWDERS BY HOT ISOSTATIC PRESSING: J. C. Runkle & J. A. Rice, Industrial r~aterials Technology, Andover, MA 01810 It is we 11 known that fi ne molybdenum «10 urn \ powders can be hot isosSatically pressed to full density at temperatures as low as 1400 C. On the other hand, 1 arger di ameter powders such as those produced by the plasma rotating electr8de process cannot be consolidated to full density at even 1500 C and 207 MPa (30,000 psi). In this study, the densification of molybdenJm was studied at

44 - TMS-AIME Annual Meeting Program pres8ures up to 310 MPa (45,000 psi) and temperatures up to 1600 C as a function of mean particle size. The resulting information was used to generate time/temperature/pressure/particle size deformation maps. Sin(...e consolidation of metal powders by hot isostatic pressing proceeds by plastic deformation the cont r i but i on of the pres sure is much more pronounced than in si mp 1 e pressure assisted sintering of ceramic powders. Nearly full density was achieved by hot isostatic pressing large diameter particles at 310 MPa (45,OCO psi). This result is important because it wi 11 allow more research on new Mo alloy made by prea 11 oyed powder meta 11 urgy methods. (9: 00 a.m.)

fcc single crystals, including pure copper and copper-cobalt and aluminum-copper alloys, will be reviewed. Particular attention will be paid to the effects of nonuniform lattice rotations caused by necking in promoting localized shearing. The theoretical part of the talk will be concerned with recent numerical simulations of finite strain deformation of single crystals including studies of necking and shear band formation. These simulations will be compared to experimental results. In particular, the predictions for lattice rotations and geometrical softening effects in localized shearing will be compared to the experimental results on lattice rotations obtained from x-ray diffraction. The talk will be concluded with a brief discussion of the iJllplications of nonuniform lattice rotations and geometrical softening in single crystals insofar as these phenomena affect polycrystalline behavior.

I(,',)ECT10N MOLDED COUJMH[lJN THRUST CHAMBER MANUfACTURING DEMON-

STRAT [ON; J. R. Wooten, Rockwc 11 Internat ional Corp. /Rocketdyne Division, Canoga Pi1rk, CA 91304 Thl' reproductibility of the injection·molding process to manufacture columbium allqy rocket engine components has been demonstrated. One hundred injection molded (Un CB-IOTa-10W attitude control t'ogine thrust chambers were sintered and evaluated. Prior to the fabrication of the chambers, a process optimization

study was perforrn('J, an ace chamber was designed for 1M, and a production mold ""a.s designed and built. A key achievement was [0 reduce thl' durat ion of vacuum sintering IN Cb-IOTa-IOW ,hdmlwrc..; ff(lln !bl) hours to 40 hours. The physical, mechanical and dim,'nsiC>l1a! .pc(Ji'ertit's were reproduced conSistently when the' sLart.Lng po\"d('r~ and processing parameters were utilized.

(9: 30 a. m. ) PRODUCTION UF P/t-l NET-SHAPE COLUMBIUM ALLOY COMPONENTS: Glenn C. Culbertson and Gerald 1. Friedman, TRW Aircraft Comp9nents Group, Cleveland, Ofl. A number of complex hollow components have been produced via HIP of spherical (CI03) columbium alloy powder. The microstructure and mechanical properties of this fully-dense PIM material have b('f'll shown to be equivalent to wrought product. The plM process routing has demonstrated significant cost savings as compared to the establ ished forge plus machine routing. The PIM routing includes: assembling sheet metal containers and ceramic cores, tilling thC' annulus with PREP C-IOJ powder, evacuating, sealing, and HIP, fol1o'..Jed by decanning and core removal. The core is !.Hoduced via a TRW proprietary process which makes it easy to rc~movl' after HIP. The fact that both the core and the powder collapse (densify) during HIP makes it difficult to arrive at design dimensions on the first try; one or more iterations is usually needed to achieve a net shape.

(10:00 a.m.) DEPENDENCE OF POWDER TYPE AND PROCESSING ON STRUCTURE AND PROPERTIES OF HIP PM NIOBIUM ALLOY C-103.; C. D. Himrnelblau and M. Kibrick; Lockheed r1issiles and Space Co.; Sunnyvale, CA. Ni obi um alloy C-103 powders produced by the Hydri de"Dehydri de and Plasma Rotating Electrode processes have ·been Hot Isostatically Pressed at various pressures, temperatures, and times. The degree and unifonnity of densification are dependent on pressure as well as temperature. The hi gh temperature mechanical behavior is influenced by processing and microstructure in ways that are not always predictable or explainable. Anomolies in impact properties have been observed. The weldabil ity of PM C-103 is strongly dependent on the content of dissolved and adsorbed gases and volatile elements. Extensive metallographic, surface, and compositional studies have been made to rationalize the mechanical test and processing behavior of the material. (10:30 a.m.) EVALUATION OF POWDER METALLURGY PROCESSED ZIRCALOY 2 AND ZIRCALLOY 4; C. C. WQjcik, Teledyne Wah Chang Albany, Albany, OR.

Zircaloy 2 and ZiFcaloy 4 were produced from Hydride-Dehydride powders. Fully dense samples were produced by cold isostatic pressing, sintering and hot isostatic pressing. The resultant microstructures and purity will be discussed and compared with conventional wrought material. Co-rrosion performance of the PIM materials was also determined in high pressure steam. Tensile properties were measured at room temperature and 316°C. Weldability and the 8ffects of impurities on weldability wi'll also be discussed.

SHEAR LOCALIZATION I Sponsored by the TMS Shaping & Forming Committee Tuesday, February 26, 1985 8:30 a.m.

Colonial Room Sheraton City Squire

Session Chairman: David Bourell, Mechanical Engineering Dept., ·University of Texas at Austin, Austin, TX

(8:30 a.m.) SHEAR LOCAUZATION IN CRYSTALLINE MATERIALS: R. J. Asaro, Box D,

Di vision of Engineering, Brown University, Providence, RI 02912 Experimental and theoretical aspects of shear band formation in ductile single crystals will be discussed. Experimental studies of shear band formation in single phase and precipitation hardened

(9:00 a.m.) THE

INFLUENCE OF TEXTURE ON

INSTABILITIES:

U.

F.

Kocks.

M.

G.

Stout, Los 'Alamos National Laboratory, Los ALamos, NM 87545, G. R. Canova, LPMM, F-57045, Metz Cedex, France and D. E. Helling, Stanford University, Stanford C.A. 94305 Even relatively mild textures can according to a well-developed theory of polycrystal plasticity, cause vertices in the macroscopic, large-strain yield surface. At such vertices, large fluctuations in the direction of the strain rate may occur upon small fluctuations in local stress. If straining in these accidental directions leads to softening, then localization of flow should begin and be sustained. Observations of shear instabilities during rolling can be quantitatively explained on this basis. Predictions of similar instabilities in equibiaxial stretching have the potential of rationalizing localized necking in this mode. Both the existence of the vertices and their correlation to instabilities will be checked by multi-axial testing of textured tubes. This work is supported by the Office of Basic Energy Sciences, Divis:1,.on of Materials Sciences, U. S. Department of Energy.

(9:30 a.m.) CONSTITUTIVE BEHAVIOR AND LOCALIZATION IN RATE DEPENDENT

POLY CRYSTALS : A. Needleman, Box D, Division of Engineering, Brown University, Providence, RI 02912 Implications of texture development a'!1d. path dependent strain hardening for the development of instability modes are discussed based on a rate dependent Taylor type polycrystal model. Although attention is focussed on nearly rate independent mat,e:rial behavior, accounting for material rate sensitivity overcomes the problem of non-uniqueness in the choice of "active" slip systems in the rate independ~nt theory so that unique predictions are obtained. Predicted lIyield surfaces" following finite pre-straining are discussed with reference to implications for polycrystal modeling. The polycrystal t s stiffness to a relatively abrupt change in loading path is determined which is key for bifurcation type phenomena such as shear band initiation. The theoretical framework also pemits a direct calculation of localized necking and shear band instability modes for polycrystals modeled as collections of individual grains.

(10:00 a.m.)

Break

(10:10 a.m.) METALLOGRAPHIC ASPECTS OF SHEAR BAND DEVELOPMENT IN ROLLED METALS: M. Hatherly. University of New South Wales, Sydney, Australia The shear bands observed in metals at high strains are characteristic of the microstructures in which they form and characteristic. therefore, of the basic deformation processes responsible for the development of that microstructure. The characteristics of the various types of shear bands will be described and their role in the nucleation of recrystallized grains discussed. Shear bands are significant features in the development of roll ing and recrysta 11 ization textures and recent work in thi s area will be described. This will include current attempts to determine the texture within a shear band, the contribution of shear band formation to hot roll ing textures and the effects of changes in strain path on shear band development and texture in heavily deformed fcc meta 1s.

(10:40 a.m.) STRUCTURAL STUDIES OF STRAIN LOCALIZATION: J.D. Embury and A. Korbel. Department of Metallurgy and Materials Science. McMaster University, Hamilton. Canada and P. Martin, Los Alamos National Laboratory, Los Alamos, NM Results will be presented to indicate the differences in the degree of strain local ization in 1100 Al, Al-Mg and overaged Al-Cu alloys. Detailed surface observations have been conducted to determine the strain bearing mechanisms operative in these materials at various strain levels and TEM studies have been performed to detennine the structure of the localized shear bands formed in Al alloys during rolling deformation.

TMS-AIME Annual Meeting Program - 45 (11 :10 a.m.) STRAIN LOCALIZATION IN Ti ALLOYS:' Mellon University, Pittsburgh, PA

J. C. Williams, Carnegie-

Strain localization has been observed in a variety of Ti alloys with resulting reductions in ductility, toughness and hot workability. The occurrence of strain localization depends on microstructure and deformation temperature. This talk will review the occurrence of strain localization in a variety of Ti alloys and discuss possible ways to mitigate it. The trade-off between strain localization and other property trends will also be discussed.

when the surface is covered by a monolayer of adsorbed impurity. Both genera 1 and 1oca 1 i zed corros i on may be caused, dependi ng on the impurity concentration in the bulk and on the surface. The mecha~isms of these effects are discussed. These results have been obtained by combining electrochemical, radiochemical, AES and ESCA Ineasurements. (11 :00 a.m.) SURFACE ANALYTICAL TECHNIQUES AND THE STtJDY OF CORROSION FATIGUE MECHANISMS: S. Suresh, Division of Engineering, Brown University, Providen
SURFACE ANALYTICAL TECHNIQUES FOR CORROSION STUDIES I: Overview and Applications Sponsored by the TMSIMSD Corrosion and Environmental Effects Committee

Recent studies of the fatigue behavior in a number of engineering alloys reveal that the formation of corr.osion deposits on the fracture surfaces has a pronounced effect on the rate of subsequent crack growth through the development of crack closure. This presentation will provide an overview of some of the recent advances in corrosion fatigue, where measurement of the extent of protective films using surface analytical techniques led to the identification and quantification of novel mechanistic processes. Specific examples of environmental effects in a number of alloy systems will be discussed.

Tuesday, February 26, 1985 8:30 a.m.

(11:30 a.m.)

*Thi5 work has been partially supported by the Office of Naval Research.

Diplomat Sheraton Centre

Session Chairmen: S. M. Bruemmer, Battelle Pacific Northwest Labora· tories, Richland, WA 99352; A. Joshi, Lockheed·Palo Alto Research Laboratory, Palo Alto, CA 94304 (8:30 a.m.) SURFACE ANALYSIS TECHNIQUES TO STUDY CORROSION - AN OVERVIEW: A. Joshi, Lockheed-Palo Alto Research Laboratory, Palo Alto, Ca 1iforni a 94303. Most reactions and corrosion processes begin to occur at solid surfaces and can be effectively studied using surface analytical techniques such as AES, XPS, SIMS and ISS. There are numerous aspects of corrosion/reactions which can be uniquely obtained by appropriate usage of these techniques and include: nature and compositions of passive films, early stages of reactions, intergranular corrosion and surface modifications. The basic principles of these techniques will be discussed as well as the merits and limitations in applying them to corrosion studies. (9:10 a.m.) GAS PHASE OXIDATION STUDIES USING SURFACE ANALYSIS TECHNIQUES: N.S. McIntyre and. T. C. Chan, Surface Science Western, University of Western Ontario Lond(;m, Canada N6A SB7

X-ray photoelectron spectroscopy (XPS) is a Burface-sensitive technique capable of yielding significant chemical information about corrosion and oxidation films on metals. A complementary surface technique, Auger Electron Spectroscopy (AES), lacks some of the chemical specificity of XPS. but is much better equipped to probe microscopic regions of a surface. For example, this micro-analytical capability has contributed significantly to an understanding of the role of grain boundaries in surface oxidation processes. Both techniques are being used in this laboratory to study the growth of thin oxides on alloy 600 and Ni-18% Cr alloys oxidized at 600 C under low pressures. The oxidation behavior of such alloys is heavily influenced by the methods of surface preparation and polishing.

(9:50 a.m.) AQUEOUS CORROSION STUDIES USING XPS AND AES: M.T. Thomas, Battelle Pacific Northwest Labor'atories, P.O. Box 999, Richland, \lA. Corrosion in aqueous environments is one of the major causes of material failure. X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES) can provide detailed information concerning corrosion film chemistry and composition homogeneity. Such information is helpful in determining the controlling mechanism for either passive film formation or continued corrosion and failure. A series of examples will be given to demonstrate the app1 itations of XPS and AES to aqueous corrosion problems which will include passive film formation on amorphous stainless steel and sea water corrosion of condenser tubing.

SOME APPLICATIONS OF SURFACE ANALYTICAL TECHNIQUES TO THE STUDY OF CORROSION IN MICROELECTRONIC FABRICATION: S. Thomas, Semiconductor R&D Laboratories, Motorola, Inc., Phoenix, AZ.

The continual scaling down of device dimensions in integrated circuits has necessitated new developments in material technology and processing techniques. These new developments have also led to new failure modes or to increased occurrence of established ones. Proper characterization of material properties and failure modes is an important facet of the successful implementation pf' new device technology and assuring reliability. To aid the microelectronics analyst who requires good spatial and depth resolution and elemental sensitivity for the analysis technique, a number of powerful surface and near-surface analytical techniques are available today. The more commonly used techniques include SEM, AES, ESCA, SIMS. This paper reviews, with illustrative examples, the application of the above analytical techniques to the study of corrosion encountered in microelectronic fabrication and operation.

THERMODYNAMICS I: ACTIVITY AND FREE ENERGY MEASUREMENTS . Sponsored by the TMS Physical Chemistry Committee and the PTDlISS Tuesday, February 26, 1985 8:30a.m.

DominionB Sheraton Centre

Session Chairmen: R. J. Fruehan, Dept. of Metallurgical Engr. and Materials Science, Carnegie Mellon U., Pittsburgh, PA 15213; G. J. W. Kor, U.S. Technical Center, U.s. Steel Co., One Tech Center Rd., Monroeville, PA 15146

(8:30 a.m.) DIRECT DETECTION OF EQUILIBRIUM BETWEEN a-Fe AND Fe 3 c:* M. C. Lee and G. Simkovich, The Pennsylvania State University, University Park, PA.

Equilibrium between a-Fe and fe3C was determined as a function of temperature (673K to 723K) by measuring the electrical conductivity of Fe3C as a function of carbon activity. The Fe C utilized was formed at 723K from fine a-Fe particles and H2 1CH4 gas mixtures. Pellets of Fe3C were then pressed and, on occasion, sintered. These pellets were brought to equilibrium with a H2 /CH 4 gas mixtures and the electrical conductivity measured utilizing a Kelvin bridge arrangement. Conductivities were essentially constant as a function of carbon activity until the a-FeFe3C equilibrium activity was reached at which point decomposition of the Fe3C provided a change in the conductivity. Calculations of the free energy of formation of the Fe 3C were made utilizing these measured equilibrium carbon activities.

*This

work was supported by the Materials Division of NSF under NSF Grant No. DMR-8203104.

(10:30 a.m.) SURFACE ENRICHMENT OF IMPURITIES ON NICKEL AND NICKEL BASE ALLOYS DURING THE CORROSION PROCESS AND CONSEQUENCES ON THE CORROSION BEHAVIOR: P. Marcus, and J. Oudar; 'Laboratoire de PhysicoChimie des Surfaces Ecole Nationale Superieure de Chimie de Paris 11, rue Pierre et Marie Curie, 75231 Paris Cedex 05 - France. We have shown that bulk impurities, sulfur and phosphorus, segregate on the surface of nickel and nickel base alloys during anodic dissolution. The early stages of the enrichment and the further evolution have been characterized. Two dimensional (adsorbed 1ayer) and three dimens i ona 1 compounds (such as sulfi des) are formed on the surface during the corrosion process. These products markedly modify the electrochemical and corrosion behavior of the metal and alloys. The passivation is inhibited

(8:55 a.m.) THE EFFECTS OF ADDITIONS OF A1203 AND CaO TO THE K20-Si02 SYSTEM ON THE ACTIVITY OF K20 IN THE LIQUID PHASE OF THE SYSTEM, 9001150 0 C: D. D. W. Smith and J. F. Elliott, Dept. of Mats. Science and Engrg., Massachusetts Instltute of Technology, Cambridge, MA 02139 The change in the activity of K20 with the additions of CaO and A1203 separately in the liquid field of the binary K20-Si02 system has been measured with an electrochemical cell. Additions of up to 10 wt. pct. of each compound were made. Alumina has very little effect, and CaO decreases the activity of K20 as is to be expected as lime is basic.

46 - TMS-AIME Annual Meeting Program (9:20 a.m.) PHYSICAL CHEMISTRY OF THE Na 2 0-TiO z SYSTEM AT 1227-1570K:* I\.~ Lin, Department of Materials Science and Metallurgical Engineerin~g, Mail Location fl12, University of Cincinnati, Cincinnati, OH.

The activity of NaZO in the NaZO-TiO Z system at temperatures between 1227 and 1570 K has been determined applying cells of the following arrangement. Pt (s), 02 (g) Na 2 0-W0 3 melt

Na+ solid electrolyte

I Na))-TiO z mixture 0 (g), Pt(s)

With the help of the NaZO-TiO Z phase diagram, the free energy of formation of compounds, such as NaZO'6Ti0 2 (NaZTi6013), has been evaluated. Due to the relatively basic property of the NaZO-TiO Z mixtures, fused silica could not be used to measure the properties of the mixture containing liquid. Experiments on solid mixtures

using fused silica as the electrolyte showed severe devitrification on the surface bf the electrolyte in contact with the Na 20-TiO Z cathode material. *This work was supported by Herman Schneider Fund and University Research Council, University of Cincinnati.

(9:45 a.m.) FORMATION OF SECONDARY INCLUSIONS IN DIRECTIONALLY SOLIDIFIED STEELS: D-C. Hu, 18M, General Tech. Div., Hopewell Junction, NY l2533,~ F. Elliott, Dept. of Materials Science and Engrg., Massachusetts Institute of Technology, Cambridge, MA 02139 The morphologies of manganese and iron sulfides and silica that fonn in Fe-Mn-Si-O-S-Ni alloys during solidification are reported. Eight mm diameter rods of the liquid alloy were solidified in a 8ridgeman-Stockbarger apparatus in which the quench medium was liquid gallium at 35 0 C. Ten percent nickel was added to all alloy compositions to permit identification of the dendrite structure in the casting. The liquid was contained in a thin-walled alumina tube. The location, composition, and physical form of the inclusions were investigated. The dendrite structure at high fractions solidified influenced strongly the shape of the secondary inclus ions.

in the ferrite iron according to log ae = 3.61757 + log Ye, which had been determined from the solubi 1 i ty of carbon in the pure iron-carbon alloy. The isoactivity lines were established from the experimental results for Fe-f\.1o-C system. The activity coefficient of Mo in the ferrite phase is determined as log ¢C = 3.61757 - 36.97YMo. The Mo/Fe ratio in the precipitated carbides and the phase equilibria in the Fe-f\.1o-C system are discussed.

The research has been supported by the- National Science Foundation through Grants D~lR-8105026 and mlR-830S732 (Equipment).

ISS/PTD Luncheon 12:00 Noon Tuesday, February 26, 1985 Sheraton Centre Hotel Embassy Suite

TMS-AIME Extractive Metallurgy Luncheon 12:00 Noon Tuesday, February 26, 1985 Sheraton Centre Hotel Imperial Ballroom A Speaker: John Elliott AISI Distinguished Professor & Professor of Metallurgy Massachusetts Institute of Technology Topic: "Metallurgy - An Evolving Techr,ology"

(10:20 a.m.) DETERMINATION OF THE LITHIUM CONTENT OF MOLTEN ALUMINIUM USING A SOLID ELEcrROLYTE: P.C. Yao and D.J. Fray, Department of

Metallurgy and Materials Science, University of Cambridge, Camb ri dge CB 2 3Qz. A lithium probe has been developed for the determination of the lithium content of molten aluminium alloys. The electrolyte is a two-phase mixture of Li3P04 and Li4Si04 to give an overall composi tion of Li 3.6510. 6PO. 4°4' This electrolyte was fOWld to be slightly attacked by pure liquid lithium but no attack was detected in the aluminium-lithium melts. However, exposure t~o high humidity caused the electrolyte to degrade. A satisfactory reference electrode was found to be decomposed Li2Ti 307 consisting of Li4TiS012 and Ti02. An activity versus composition plot showed that Henry's law was obe"ed and the activity coefficient was 0.17 at 984 K and 0.26 at 1050 K.

(10:45 a.m.) EQUILIBRIA BETWEEN CARBON AND OXYGEN IN MOLTEN IRON IN CO/COZ ATMOSPHERES: M.E. Guzman* and D.G.C. Robertson** *Department of Metallurgy and Materials Science,U.C.V., Caracas,Venezuela.**Department of Metallurgy and Mater ials Science, Royal School of Mines, Lord on ,Englan:l . The effect of carbon on the activity coefficient of oxygen was determined by equilibrating CO/CO Z gas mixtures with mol ten iron at temperatures of 1550,1650 and 1750 °c and at total press ures up to 80 atmos pheres in a high pressure levitation apparatus. The results confirmed that the activity coefficient of oxygen increas es with the increas e of carbon concentration in liquirl iron according with tne equation logf o =0.06(± O.OZ)wt%C. The carbon-oxygen product relative to 1 atmos phere part ial press ure of carbon monoxirl e d ecreas ej with the increas e of carbon concentration extrapolation at very low carbon concentration gave the value O.OOZ in the temperature range used in this work. I

(11:10 a.m.) niER~iODYNA~IlCS A~D SOI.IJBILITY 0, CAPBiDES TN THE FF.RRTTIC FF.-~10-C ALLOYS AT 712°C: H. \\;aua,. Department of Materials & Metallurgical Engineering, Uni\"er-sl~of II-lichlgan, Alln Arbor, 11-11 48109. Phase equilibria ill the ferritic Fe-Mo-C system containing 0 to 2.9Ya~1O have been studied at 712°C. The 0.5 mm thick foj I samples of Fe, Fe-Mo and Fe-C alloys Y·;ere scaled into a quartz tube under adjusted hydrogen pressure and equi librated. The quenched specimens were analyzed for total l?oC) and (°011-10) in the ferrite matrix, and (?-o[llo) in the preclpitatod carbides. The carbides were extracted from the ferrite matrix and identified by the X-ray diffraction. The carbon actiVIty was determined from the carbon content

TMS-AIME Extractive Metallurgy Lecture 1:45 P.M. Tuesday, February 26, 1985 Sheraton Centre Hotel Imperial Ballroom B Lecturer: Leslie R. Verney Consulting Engineer Union Miniere S.A. Brussels, Belgium Topic: "Developments in Copper Extractive Metallurgy'"

TUESDAY PM ADVANCED MATERIALS AS POTENTIAL REPLACEMENTS FOR CONVENTIONAL SUPERALLOYS Sponsored by the TMS-AIME High Temperature Alloys Committee Tuesday, February 26, 1985 2:00 p.m. .

Province Suite Sheraton Centre

Session Chairmen: Ronald C. Gebeau, Carpenter Technology Corp., P.O. Box 662, Reading, PA 19603; P. K. Wright, General Electric Co., Materi· als Technology Laboratory (M87), Evandale, Ohio 45215

(2:00 p.m.) RESEARCH PROGRESS ON THE 82 ALUMINIDES: J.. R. Stephens, NASA Lewis Research Center, Cleveland, OH 44135. A research effort is under way at NASA Lewis Research Center to explore the potential of the 82 aluminides as structural material alternatives to conventional superalloys currently used in

TMS-AIME Annual Meeting Program - 47 gas turbi ne engi nes. Emphasi sis bei ng pl aced on the equi atomi c Fe, Co, and Ni aluminides. The aluminides are of interest because of their high melting points (NiAl and CoAl), their potential for good oxidation resistance, they exist over a broad range of composition, have large solubilities for third element alloy additions, have relatively low densities, and low cost (FeAl and NiAll. Research focuses on initial processing techniques such as ingot melting, powder metallurgy, rapid solidification, and thermomechanical processing; high temperature deformati on-primarily compress i ve creep; compos i ti ona 1 effects wi thi n the B2 binary aluminides; third-element alloying addition effects on high temperature strength and oxidation resistance; and near room temperature ductility as i nfl uenced by process i ng, alloying, and grain size. This paper will summarize the results obtained to date.

(2:30 p.m.) ADVANCE:S IN HIGH TEMPERATURE TITANIUM ALLOYS AND TITANIUM-MATRIX COMPOSITES: G. E. Eichelman and F. H. Froes, Air Force Wright Aeronautical Laboratories, /;,aterlals 'LabOratory, AFWAL/MLLS, Wright-Patterson AFB, CH QSQ33 Titanium and titanium alloys offer an attractive combination of mechanical properties for use in demanding applications. This includes use in applications at elevated temperatures, up to SSooC (10000F). These properties can be further enhancea by use of reinforcing fibers which can greatly increase properties such as modulus of elasticity. This paper will aiscuss recent advances in high temperature titanium alloys using both ingot metallurgy and powder metallurgy/rapid solidification approaches. In combination with fiber reinforcement (SiC, BORSIC, B4 C/B) these advances allow the titanium al loy fami Iy to compete with superalloys in demanding applications. This presentation will place the present status of high temperature titanium alloy development In a historical perspective and project possible future advances.

the unique property combinations lead to significantly enhanced systems performance. This paper will briefly review the properties of the silicon nitride, silicon carbide and zirconium oxide families of ceramics. With this background, examples of current applications of high performance ceramics in gas turbine and diesel engine applications, and metal cutting and shaping applications will be provided.

ADVANCES IN TITANIUM WELDING IV: Applications Sponsored by the TMS Titanium Committee Tuesday, February 26, 1985 2:00 p.m.

Jefferson Suite Sheraton City Squire

Session Chairmen: J. A. Hall, Henderson Technical Laboratories, TIMET, P.O. Box 2128, Henderson, NV 89015; I. L. Caplan, David W. Taylor Naval Ship Research and Development Center, Code 2812, Annapolis, MD 21402

(2:00 p.m.) PRACTICAL WELDING CONSIDERATIONS FOR INDUSTRIAL APPLICATIONS:

P. L. Cahill, R. L. Kane, Titanium Industries Incorporated,

Fairfield, NJ. Economic restraints dictate choice of welding techniques and procedures for the majority of industrial applications of titanium. Factors which effect these choices will be analyzed. Technological variables of type of welding when applied to different fabrication and erection conditions will be discussed. Examples will be discussed.

(2:35 p.m.) (3:00 p.m.)

Break

EXPLOSIVELY CLAD TITANIUM FOR INDUSTRIAL APPLICATIONS:

D. Brasher, A. Hare,

(3:15 p.m.) ADVANCES IN IN SITU COMPOSITES: F. D. Lemkey, United Technologies Research Center, East Hartford, CT. During the twenty-five years since R.W. Kraft's original efforts to produce an entirely new class of anisotropic eutectic materials, i.e., in situ composites,there has been an explosion of their technological development. Some of this work has led to commercial applications (e.g., novel electrical, magnetic, and optical devices) while others have involved sustained and substantial efforts to replace conventional superalloys in gas turbine engines. Transfer from laboratory scale to precision investment casting has been achieved to produce components for engine testing. The engine test results and present status of 73C, NITAC-14B, COTAC-744, y/y'+6 and y/y'+Cr3C2 eutectic superalloys will be reported. In addition, the newer uses of in situ composites, e.g., electrostatic atomizers, strengthened conductors, electron emitters, will be discussed as they relate to high temperature materials application.

North~est

Technical, Sequim,

WA.

Explosively cladding of titanium allows more thorough utilization of the desirable industrial properties of titanium. Explosive bonded Grade 1 titanium to copper and to aluminum bimetallics along with titanium as a diffusion barrier in trimetallic systems will be discussed.

(3:10 p.m.) FABRICATION AND I;ELDING OF TITANIUM FOR INDUSTRIAL APPLI-

CATIONS: C. S. Young, N. E. Weirick, Astra Metallurgical, Wooster, OH. Fabrication and welding techniques for Ti for industrial equipment will be discussed. Procedures that ensure high quality will be described. Cleaning, joint design and preparation, fit up, shielding, and post-weld treatment will be discussed in terms of quality control requirements.

(3:45 p.m.) (3:45 p.m.)

FABRICATION OF EXPLOSION BONDED TITA-'HUM CLADS - 20 YEARS'

ADVANCES IN CERAMIC MATRIX COMPOSITES: Karl M. Prewo, United Technologies Research Center, Silver Lane, East Hartford, CT 06108 In the past many attempts have been made to utilize monolithic ceramics in place of superalloys for high temperature applications. In

EXPERIENCE:

A. Pocalyko, Du Pont Company, Coatesville, PA.

Explosion bonded titanium clads were introduced in 1964. Since then, literally hundreds of vessels and tube sheets have been fabricated from such clads. Cladding, joining, forming and use experiences are described.

each of these cases the area of major concern has been the low

failure strain of the ceramic and its tendency for brittle failure. This presentation will describe the recent progress made to

overcome this brittleness problem through the use of fibers to reinforce and toughen ceramic matrices. It will be shown that even

though both the reinforcing fibers and the matrices are by themselves low failure strain "brittle" materials, the resultant

composites can be extremely fracture tough. The silicon carbide fiber reinforced glass and glass-ceramic systems will be discussed in

detail to describe the general types of properties which can be achieved. Strengths in excess of 100,000 psi at temperatures of up to 1000·C will be presented along with evidence of toughness that is well beyond that typical of monolithic> ceramics. It will be shown that fabrication procedures permit the direct production of parts with complex shapes, without the need for machining.

(4:15 p.m.) ADVANCES IN MONOLITHIC CERAMICS:

R. N. Katz, Army

Materials and

Mechanics Research Center, Watertown, MA 02172. Modern high-performance ceramics possess unique combinations of properties which make them attractive candidates for many applications in severe envirorunents. In many of these applications

(4:20 p.m.) WELDING, BRAZING AND REPAIR APPLICATIONS IN TITANIUM AEROSPACE STRUCTURES: .R. H. Witt and A. C. Lofsten, Grumman Aerospace Corporation, Bethpage., NY 11714. Stringent demands for higher performance supersonic aerospace vehicles have caused the aerospace industry to make significant advances. in material and process usage for the design and fabrication of critical structures. This paper is concerned with current applications of titanium welded, brazed and repaired aerospace structures. The selected applications are concerned with joining titanium in various gages ranging from sheet to heavy p'late and forgings in secti"ons up to 2 to 3 inches thick. Major applications discussed in this paper relate to fusion welding the center wing box and wing outer panels on the F14, the main forward spar on the X-29 aircraft and the MX missile shroud. Tube welding and braxing hydraulic lines on the F14 and resistance welding applications on the E2, C2 and F14 aircraft are also addressed. The. importance Of iryspestion and re~air are also discussed. Part1cular emphas1s 1S glVen to repalr of weldments and discrepantly machined parts that would otherwise be scrapped resulting in large cost penalties.

48 - TMS-AIME Annual Meeting Program ALUMINA & BAUXITE III: Bayer Process Fundamentals Sponsored by TMS Light Metals Committee Tuesday, February 26, 1985 2:30 p.m.

Royal Ballroom, B Sheraton Centre

Session Chairmen: Joseph L. Anjier, Kaiser Aluminum, P.O. Box 1031, Baton Rouge, LA 70821; Carlos M. Padial, Martin Marietta Aluminum, Box 165 Kingshill, St. Croix, Virgin Islands 00850

(2:30 p.m.) THE KINETICS OF GIBBSITE EXTRACTION IN SYNTHETIC LIQUORS. W. E. Wahnsiedler, Alcoa, Alcoa Technical Center, Alcoa Center, PA A series of experiments was performed to measure the rate of extraction of Gibbsite from three Alcoa bauxites: Trombetas, Suriname and Kwinana. The bauxi tes were crushed and screened before extraction and the rates were measured as functions of digest temperature (lOS-143C) and initial particle size (average initial radii between 0.000089 m and 0.00056 m). The results were found to be reasonably well represented by a model in which the rate of extraction at each particle is assumed to be proportional tn the active surface area (as measured by B.E. T. apparatus) and to the extent of the difference between the asymptotically approached liquor alumina concentration and the current liquor alumina concentration. The rate constants were fit to on Arrhenius equation to account for temperature variation. The Arrhenius activation energy for extraction was found to be 6.7 + 1.3 k cal/mole Al 2 0 3 for Suriname bauxite and 5.4 ~ 1.6 k cal/mole Al')O for Kwinana bauxite. Particle size distributions in the residue showed size degradation unaccounted for by extraction. ~his is believed to be due to breakage and disintegration of the residue after extraction.

(3.00 pm.) 'cE INFLUENCE OF MINERALOGY ON THE DISSOLUTION KINETICS OF I;JBBSITE: G,I.D.Roach, Plcoa of Australia Ltd., Kwinana, '~'estern Aust~

n,e

dissolution of sized particles of naturail y occurring and synthetic gibbsites (hydrate from the Bayer process) in sodium I'lydroxide solutions at temperatures from 65°C to 150°C were studied. The dissolution rates varied by more than an order of magnitude with gibbsite type; natural gibbsite had the fastest rate, a result of its higher porosity and surface area. For the synthetic gibbsites, a linear Arrhenius plot was obtained and the activation energy of 105 kJ.mol- 1 agreed with that of previous workers. For the natural gibbsite, the plot was not linear; the dissolution rate was less sensitive to temperature at the higher temperatures. The effect of particle size on dissolution rate also depended on gibbsite type, there was a marked effect for synthetic gibbsite but little for natural gibbsite. A dissolution model based on the differences in mineralogy of the gibbsites is proposed to explain the observed temperature and particle size effects. (3:30 p.m.) THE HEAT OF DISSOLUTION OF GIBBSITE AT BAYER DIGESTION TEMPERATURES: J.M. Langa; Alumina, Chemicals and Ceramics Division; Alcoa Technical Center; Alcoa Center, PA 15069 The heat of react i on of gi bbs ite in caust i c sol ut i on has been reported by various sources; the average value being 140 kcal/kg Al O. Although this value has been determined from solublity 6r 3 calorimetric data at normal Bayer precipitation temperatures, it has been widely used in Bayer Process mass and energy calculations at digestion temperatures. However, using correlations for gibbsite and Bayer liquor heat capacity, and National Bureau of Standards heat of formation data, the heat of dissolution of gibbsite at Bayer digestion temperatures (145°C) has been calculated at 200 kcal/kg Al O~. This paper describes the theoretical thermodynamic treat~e~t and the experimental verification (by calorimetry) of this higher val ue. (4:00 p.m.) THE EFFECT OF IMPURITIES ON CALCIUM IN BAYER LIQUOR: P. J. The, and T. J. Sivakumar, Aluminum Company of America, Alcoa Technical Center, Alcoa Center, Pennsylvania 15069 An experimental invest i gat i on has been conducted to study the effect of liquor composition on the calcium content of Bayer liquor. Laboratory and plant data show that the presence of organi c compounds and sodi um carbonate in 1 iquor si gnifi cantly affect the calcium content in liquor. Calcium concentration increases with i ncreasi ng organi c carbon and sodi um carbonate concentrations. Not all organic compounds in Bayer liquor have the same effect on the solubility of calcium. Laboratory studies show that at low temperature digest conditions (143°C) organic compounds with di-, tri- and tetracarboxylate groups, slightly affect the calcium solubility in varying degrees depending on their concentrations. Humic material and organic compounds with 5-hydroxyl groups significantly increase calcium so 1ubil i ty in these 1i quors. In a 11 cases, hi gh temperature digestion (235°C) resulted in very low calcium concentration in liquor for all the impurities investigated except for humate.

(4:30 p.m.) STRUCTURE AND DECOMPOSITION MECHANISM OF SODIUM ALUMINATE LIQUORS By ~, ALUTERV-FKI, Budapest, Hungary Research coordinated by ALUTERV-FKI with freshly prepared liquors has established that characteristic concentration ranges exist in the Na 2 0-Al Z0 3 -H 0 system which can be related to the hydration state the aluminate species. The variation of the amount of hydration water and of OR ions set free as a result of the coupling of AIOH 4 - ions has been measured. The structure of the dimers has been determined by low-angle X-ray analysis, and the size of the larger structures by light scattering measurements. The processes going on in the liquor phase and on the surface of seed crystals, the agglomeration of the crystals and the effect of various impuritites (carbonate, sulfate, chloride, organics) on the decomposition process have been investigated in the presence of seed. The effect of sodium aluminate liquor concentration and impurities on product grain size and attrition index can be understood from this study.

of

(5:00 p.m.) Properties of Scale in Bayer Process K. Yamada, M. Yoshihara & S. Tasaka Sumi tOiii'OAluminium Smelting Co., Research Institute of Inorganic Materials, Niihama, Japan Scales such as sodalite, gibbSite, boehmite and sodium oxalate are formed in Bayer process. Scale formation conditions and removing methods of scales are presented in this report. Sodali te scale on the heat exchange surface in a digestion process reduces the heat transfer coefficient. This dec:-,e~se of heat transfer coefficient was related to the desilication rate.

ALUMINUM REDUCTION TECHNOLOGY III: Modeling Sponsored by TMS Light Metals Committee Tuesday, February 26, 1985 2:30 p.m.

Royal Ballroom A Sheraton Centre

Session Chairmen: R. D. Zabreznik, Kaiser Aluminum & Chemical Corp., P.O. Box 1600, Chalmette, LA 70044; S. Jacobs, Aluminum Company of America, Alcoa Center, Pittsburgh, PA 15069 (2:30 p.m.) A PHYSICAL MODEL FOR ELECTROMAGNETICALLY DRIVEN FLOW IN HALL CELLS, Huai-Chuan Lee and J. W. Evans, Department of Materials Scienoe & Mineral Engineering, University of California, Berkeley, Berkeley, CA 94720 Various mathematical models have been developed for electromagnetically-driven flow of electrolyte and metal in Hall cells; attempts have been made to relate the flow to design or operating practice. Experimental confirmation of effects predicted by these models has been hindered by the difficulty of performing measurements on cells and the expense of making changes to actual operating cells. A "cold" physical model has been developed at Berkeley which is aimed at both testing mathematical models for electromagnetically-driven flow and providing an opportunity for experimentally determining the effect of changes in cell design or operation. The model is imperfect in that it uses only one liquid (Wood's metal), but that liquid moves with velocities of 1-2 cmlsec, in rough agreement with the predictions of a mathematical model when the model dimensions and physical properties are used. The effect of such changes as replacing an anode is being studied using the model. (2:55 p.m.) MAGNETICS AND METAL PAD INSTABILITY.

N. Urata, Kaiser Aluminum

& Chemical Corporation, P. O. Box 877, Pleasanton, CA 94566

A method to evaluate the metal pad instability was developed. The electrolyte and the molten metal were treated as a two-layer fluid whose interface· is electromagnetically disturbed. An interfacial wave equation with the electromagnetic force term in it was solved along with an equation for the electrical current distribution. The result showed that the instability was governed by the distribution pattern of the vertical component of the magnetic field rather than its absolute intensity. Based on the result, an alteration was. made to our prototype 200 kA cell bus configuration, which led to an improvement of the

metal pad stability. (3:20 p.m.) HEAT LOSSES OF DIFFERENT POTS:

W. Schmidt-Hatting, Swiss Aluminium Ltd., Primary Aluminum, CH-8034 Zurich, J .M. Blanc, J.C. Bessard, R. V. Kaenel, Swiss Aluminium Ltd., R&D, CH-3965

Chippis For reducing electrical energy consumption, it is important to know the heat losses the pot shell suffers through its boundary

TMS-AIME Annual Meeting Program - 49 surfaces. These losses are determined by calculation and measurement. Multi-dimensional, mathematical computer models, which have been verified by a series of measurements on production pots, are available for the calculations. The results of the calculations and measurements are compared with one another. The individual heat losses are discussed in function of the chosen lining, the pot1ife and the kind of servicing. The use of the methods of calculation for dimensioning new pots is shown.

(3:45 p.m.)

microohm-meter.) In a1dition , green coke anodes had low carbon consumption in a bech-scale test cell and were more resistant to air burning than calcined coke anodes.

(3:00 p.m.) EFFECTS OF MIXING VARIABLES AND MOLD TEMPERATURE ON PREBAKED ANODE ~ALITY: David Belit.kus. Alcoa Laboratorie •• Alcoa Center, PA lS069 Bench-scale work was carried out to determine effects of mixing

THE HYDRODYNAMICS OF THE HALL-HEROULT CELL - AN OVERVIEW: Daniel K. Ai, Aluminum Company of America, Alcoa Technical Center, Alcoa Center, FA 15069 The hyd:rodynamics of the Hall-Herault cell, in recent years, has attracted a great deal of attention, essentially due to the need of: 1) better basic understanding, and 2) improved computer control. While many interesting hydrodynamic problems have already been tackled, an overall view is still missing. The

complexity of the flow field is believed to be the deterrent. Specifically, the problem requires. as reflected by the many phenomena in the cell, an interdisciplinary treatment involving the following domains: Electromagnetism and MHD; Electrochemistry; Wave Motion and Stability;' Turbulence; Heat and Mass Transfer; Two-Phase Flow. To make matters worse. the problem 1s intrinsically unsteady in nature. In this paper. various

phenomena will be described with the aid of dimensional analysis and the characteristic features. in particular the unsteady kind J will be discussed.

(4: 10 p.m.) CATHODE COLLECTOR BAR TEMPERATURE AND CURRENT PICKUP: R. F. Boivin, P. Desclaux and J. P. R. Huni, Alcan International Ltd •• Jonquiere, Quebec, Canada, G7S 4K8 Ten thermocouples and voltage probes were built in along a cathode collector bar in a large-amperage aluminum electrolysis cell. After the initial transient associated with start-up. the temperatures along the bar are found to be quite uniform.

showing a dip of only about 80·C at the end of the block.

The

highest temperature along the bar, on the other hand. Is not at the center of the cell but near the quarter points. The correlation between bath and collector bar temperatures is extremely good. An analysis of the voltage data shows a steady evolution, during the first six months at least, of the current pickup

along the bar. The last third of the bar picks up at least half of the total current. This experimental study was paralleled by a theoretical study with computer models of various complexities. Some comparisons of measured data and theoretical results are given along with some suggested interpretation of the phenomena.

(4:35 p.m.) CllRRENT EFFICIEOCY l\ND ALUMINA CONCENTRATION: B. Lillebuen and T. Mellerud, Norsk Hydro a.s, Res. Centre, 3900 Porsgrunn,

time on quality of prea.ed and vibrated prebaked anode •• Effect. of coke and pitch preheating and mix and mold temperatures were determined also. Green and baked apparent den.ities of pre. sed anode. increased by 0.02 Mg/m 3 on increasing mixing time from S minutes to 60 minutes. Most of the density increase occurred and baked anode electrical resistivity minimized after 30 minutes of mixing. Coke and pitch preheating had little effect on the bench-scale pressed anodes. A mold temperature 30·C over the pitch softening point (cube-in-air) improved pressed anode properties compared with a mold temperature 10·C over the softening point. Vibrated anode properties were optimum with a lS...,.inute mixing time. With long er mixing times. properties were greatly degraded. A mix and mold temperature 40'C over the pitch softening point was optimum for vi bra ted anode •• (3:30 p.m.)

MIXING AND LABORA'lDRY Bl\KING OF SOEIlERBERG PASTE: P. Stokka, Norsk Hydro a.s, Res. Centre, 3900 Porsgrurm, Norway. A new method for laboratory baking of Soederberg paste is described. The method is based on heat treatnent of the paste before the actual baking. The gas trapped. in the coke pores during the mixing is thereby allowed to expand, penetrate and escape fran the paste. After the heat treatment the paste is baked under a pressure of 40 g/an2 • The density thus obtained in laboratory baked sanples is close to what is found in plant arodes. The effect of coke preheating tenperature and the mixing tenperature on paste flowability and the percent of pitch necessary to reach a certain flowability is deronstrated. The paper also describes how the mixing tenperature is used to obtain a stable anode top in dry anode operation. (4:00 p.m.) ANODES MADE WITH 86 PERCENT BUTTS: M. C. Fon~, R. Carneiro, E. De Bango, Aluminio Del Caroni, S. A. (Alcas8, Zona Industrial Matanzas 8016, Ciudad Guayana, Venezuela. Anodes with 86% butts for aluminium reduction pots were made and tested in Alcasa. Total of 6000 anodes were made with 24% coarse, 34% medium , 42% fines all from butts. Pitch was 14%. After baking in a Riedhammer baking furnace on 36 hours cyc Ie, the anodes were rodded and tested in the aluminium reduction pots. Results were 0.722 gross and 0.497 net carbon consumption. Pot operation gave a metal quality of 99.83%(4A), ampere

efficiency of 89.47%. with 1,063 ki los per pot day at 147.59 KA.

_yo

A reaction JTCde1 for the back reaction between carbon dia>tal- and gas-solubilities, gas bubble sizes, and the physical-chernical data for the cell electrolyte, we have calculated how the current efficiency should vary with the concentration of dissolved alunina in the electrolyte. These calculations are then utilized in a qualitative discussion of currmt efficiency behaviour in laboratory cells and different types of plant cells.

CARBON TECHNOLOGY III Sponsored by the TMS Light Metals Committee Tuesday, February 26, 1985 2:30 p.m.

Georgian Ballroom A Sheraton Centre

Session Chairmen: P. G. Campbell, Alumax of South Carolina, P.O. Box 1000, Goose Creek, SC 29445; Curtis J. McMinn, Reynolds Metals Company, Reduction Laboratory, P.O. Box 1200, Listerhill (Sheffield), Alabama 35660

ENERGY REDUCTION TECHNIQUES IN METAL ELECTROCHEMICAL PROCESSES IV Sponsored by TMS-AIME Electrolytic Processes Committee Tuesday, February 26, 1985 2:30 p.m.

Versailles Ballroom Sheraton Centre

Session Chairmen: Paul F. Duby, Henry Krumb School of Mines, 905 S.W. Mudd Bldg., Columbia University, New York, NY 10027; William W. Harvey, 4 Old Colony Lane, Arlington, MA 02174

(2:30 p.m.) SAVING ENERGY BY USING FUEL CELLS OR ANODE DEPOLARIZATION: * G. M. Cook and M. Krumpelt, Chemical Technology Division. Argonne National Laboratory. Argonne, IL 60439. Some existing and proposed metal electrowinning plant sites have by-product .... terial. available that can be used to reduce the

(2:30 p.m.) PROPERTIES OF BENCH-SCALE GREEN COKE ANODES: Quyen C. Nguyen Aluminum COmpany of America, Alcoa Laboratories, Alcoa Center)

PA 15069. In order to increase the fundamental understanding of the carbon electrode binding, green coke was used as filler in replacement of calcined coke. Due to the reactivity of green coke with binder during baking, high performance bench-scale green coke anodes can be made successfully with green cokes and patroleum resids and/or pitch binder. Since the carbon aggregate particles were chemically bonded to one another in the green coke anodes, their physical properties were better than those of regular 3 calcined coke3anodes (e. g., baked apparent dens i ty: 1. 66g/ cm vs. 1.53 g/cm ; electrical resistivity: 45 microohm-meter VS. 60

need 'for purchased energy. For example, hydrogen can be used to reduce the energy consumption of electrowinning processes by

depolarizing the anode. thereby reducing cell potential by about 0.8 V/cell. Alternatively. it might be u.ed in a fuel cell to generate dc electricity and heat at high efficiency. Electricity can be produced by a fuel cell with an efficiency of about 45 to SO%. compared to about 30 to 32% for conventional generating equipment. Furthermore. the heat produced i. readily available at temperatures which vary from about lSO·C for pho.phoric acid fuel cell. to SSO to 800·C for advanced high temperature fuel cell systems. This paper examines the increased complexity that these techniques impose upon the electrowinning process, assesses the extent of energy savings that are available, and provides insight into the impact on capital and operating costs. *Worlt .upported by USlDOE under contract No. W-3l-l09-ENG-38.

50 - TMS-AIME Annual Meeting Program (2:55 p.m.) CHARACTERIZATION OF CATALYTIC DEPOLARIZATION KINETICS:

_T.W. Chapman, and S.-C. Yen, Chemical Engineering nepartment, U---n-i-;ersity'of i-Jisconsin, Madison, WI.

studied. Experiments were carried out to test the advantages of separating the anolyte from the catholyte by an iooexchange membrane. The selection and the design of a suitable electrode are discussed in relat ion to the economics of the process.

HERBERT H. KELLOGG SYMPOSIUM: General II Sponsored by The Physical Chemistry Committee and The Copper, Nickel, Cobalt and Precious Metals Committee

Cell voltage and power consumption in electrolytic processes may be reduced by replacing a high-voltage electrode reaction by one that occurs more readily, that is, at lower potential, for either thermodynamic or kinetic reasons. The polarization characteristics of candidate reactions may be readily determined by measurements on a rotating disk electrode. Transport-reaction models have been developed to allow determination of rate parameters from polarization curve data, and these also provide a basis for predicting depolarization effectiveness. Examples include anode depolarization by sulfite, catalyzed by either ferrous or iodide, and cathode depolarization by oxygen. catalyzed by cupric in either chloride or ammonia solution.

Session Chairmen: S. E. Khalafalla, Bureau of Mines, 5629 Minehaha Ave. South, Minneapolis, MN 55417; B. L. Tiwari, General Motors Research Laboratories, Warren. Michigan 48090

(3:20 p.m.)

(2:30 p.m.)

AN INVESTIGATION OF SULFITE ION OXIDATION AS AN ALTERNATIVE ANODIC REACTION IN FLUIDIZED BED ELECTROWINNING OR OTHER HIGH RATE ELECTROLYSIS CELLS: K. A. Spring and J. W. Evans, Dept. Mat. Sci.

Min. Engrng .• Univ. of Calif.. Berkeley, Berkeley, CA

94720.

The oxidation of sulfite ion to sulfate ion appears to offer attractions as an anodic reaction for cells operated- at high current density such as those used in the fluidized bed electroclepnsition of metals. In the present investigation several anodes were tried in a cell where the anolyte was aqueous ammoniurr: sulfite solution and copper was electrowon from acidified 3CjtlCOUS cupric sulfate solution onto a fluidized cathode. The cell vol tage was determined as a function of current density and :1 porous anode consisting of reticulated vitreous carbon with a ll';Jd coating was found to yield low cell voltages as did a DSA "m(lue. The former anode did not evolve oxygen in the current dens i tv range up to 5500 A/m2 whereas the lat ter showed the 00c-,-·t of evolution as the current density was raised. Below 3,'i00 sulfite ion oxidation using the reticulated vitreous ,'arbun anode resul ted in cell voltages below those of convent i,mal commercial cells for copper e1ectrowinning. (3: 45 P .;n. ) REDUCTION OF ENERGY CONSUMPTION IN ZINC ELECTROWINNING BY ANODE DEPOLARIZATION WITH ORGANIC ADDITIVES: D. Buttinelli -

Department of Chemical Engineering, University

of

Roma - Italy

Power requirements in zinc electrowinning can be reduced by substituting an other anodic reaction for oxygen evolution or by the use of D.S.A.; however these routes are not without their drawbacks: expensive plant modifications and higher anode manufacturing cost. Another viable alternative is the anode polarization reduction by organic additives. Preliminary laboratory tests showed .that low concentrations (O.OOSO.IM) in the electrolyte of some organic compounds, such as ethanol, acetic ac., ethylene glicol are effective in decreasing anode polarization and overall cell voltage by 100-200 mV. Energy saving up to 6% should be so obtained. Other advantages include lower Pb contents in cathode zinc and lesser amounts of Mn0 2 anodic slime. Results of laboratory and semiindustrial pilot tests will be discussed.

(4: 10 p.m.) SAVING ENERGY DSA FOR Ni AND Zn ELECTROWINNING--A LABORATORY STUDY:* Y. X. Liu, L. H. \olu and B. L. Yuan. Central-South Insti-

tute of Mining to Metallurgy, Changsha, Hunan 410012, CHINA. Four types of dimensionally stable anodes (DSA) which could be used in sulfate solution for Ni and Zn electrowinnine have been studied. These DSA were Ti!TiO,-RuO, (Il; Ti!SbDx-SnO'/MnO, (II); graphite-based Ti02-Ru02 (III) and ceramic-based Ti02-Ru02 (IV). Anode(III) had the best electrocatalytic activity and the lowest oxygen overvoltage. The overvo1tage increasin,2 order was as follows: III
(4:35 p.m.) FUEL-ASSISTED METAL ELECTROWINNING:

Paul Iluby, Henry Krumb

School of Mines, Columbia UniverSity, New York, N.Y. A significant reduction in energy consumption for aqueous electrowinning can only be achieved by modifying the chemistry of the system. One approach consists of leaving the cathodic process unchanged and replacing the anodic oxygen evolution by the oxidation of a soluble fuel. This paper reviews and updates some laboratory results obtained with methanol and with sulfur dioxide. The application of this concept to the electrowinning of copper, zinc and manganese was investigated. The influence of impurities and the effect of periodic current reversal on both the anodic and the cathodic reactions were

Tuesday, February 26, 1985 2:30 p.m.

RECOVERY OF

FLUORIT~

Regency Ballroom Sheraton Centre

AND BYPRODUCTS FROM THE FISH CREEK OEPOSIT,

EUREKA COUNTY, NEVADA.* D. G. Foot, Jr., F. W. Benn, and J. L. Hui,1tt, Salt Lake City Research Center, Bureau of Mines, U.S.Department of the Interior, 729 Arapeen Drive, Salt Lake City, tIT. The Bureau of Mines investigated flotation methods for recovering fluorite and byproduct beryllium from the Fish Creek deposit of Nevada. The preferred method includes (1) fluorite rougher and cleaner flotation, (2) desliming at 2011m, (3) muscovite flotation, (4) silicate flotation, (5) hypochlorite wash of silicate concentrate, and (6) beryllium rougher and cleaner flotation from the silicate concentrate. Laboratory results showed that over 94 pet of the fluorite was recovered in a concentrate containing 96 pct CaF2~ Beryllium flotation produced concentrates containing in excess of 5 pct BeO with recoveries over 70 pet. A IOO-lb continuous flotation unit was operated to demonstrate this procedure.

(3:CC 1'.111.) FIRE-REFINING OF CHLORIDE-LEACH COPPER, R. R. Bhappu and W. G. Davenport, Department of Metallurgical Engineering, University of Arizona, Tucson, AZ 85721 The coppers which are electrowon from industrial chloride leach solutions are considerably more concentrated in impurities than the coppers produced by electrorefininCj or electrowinning from sulphate solutions. This paper describes an experimental study of pyrometallurgical techniques for purifying this copper. Three basic techniques have been examined: (i) vaporization, possibly assisted by chlorine which is inherently present in the copper; (ii) halogenation and (iii) oxidation. The experiments were carried out between 873 K and 1423 K in the solid (as received) state and in the liquid state. The results indicate that: a) Bi and Pb can be removed to below 1 ppm by vaporization but Fe cannot:" b) halogenation with Freon 12 gas is effective in removing Bi , Pb and Fe to below Ippm; c) oxidation is effective in removing Fe but not Bi or pb. Mechanisms are discussed and proposals for a purification process are outlined.

(3:30 p.m.) PYROHYDROL YS I S OF NICKEL CHLOR I DE SOLUTION I N A 30- INCH DIAMETER FLUIDIZED-BED REACTOR, Mahesh C. Jha, Bruce J. Sabacky, Gustavo A. fleyer, AMAX Extractive-R&D,---rnc:-; Golden, CO 80403 and A~IAX Zinc Cnmnany, East St. Louis, IL 62202. AMAX has developed a chloride refining process to produce pure nickel and cobalt metals from mixed sulfide precipitates. Metal chloride solutions, generated in a hydrochloric acid leaching step and purified in a solvent extraction circuit, are converted to metal oxides and HCl gas by pyrohydrolysis. A pilot plant consisting of a 30-inch diameter fluidized-bed reactor and other ancillary units was designed, constructed, and operated for over one year. Process design was aimed at minimizing energy consumption, maximi zi ng conversi on effi ci ency, and achievi ng s imp1i ci ty of opera t i on and contro 1. The opera t i on provi ded va 1uabl e information on process sca 1e-up parameters, process-control strategies, and materials of construction. Several process variables such as bed temperature, bed height, solution composition, solution feeding system, oil combustion system, and fines recycle system were investigated to determine their effects on the process efficiency and physical and chemical characteristics of the product.

(4:00 p.m.) 1985 UPDATE ON TIN SMELTING AND REFINING TECHNOLOGY: T. S. Mackey, Key Metals and Minerals Engineering Corp. and Partner, Thomas S. Mackey,P.C.,Attorneys, Texas City, Texas, USA.

A technical review is made of prior, current and possible future worldwide practice for the pretreatment, smelting and refining of tin metal. Special emphasis is placed on processes, reagents, such as reducing agents, and equipment used in the extraction and purification of tin metal from high and low grade tin concentrates and residues. Applications of electric smelting, and possible plasma arc smelting in the future are covered. Prices, production and consumption, and commercial and technical developments are reviewed in some detail.

TMS-AIME Annual Meeting Program - 51 HYDROMETALLURGY/CHEMICAL PROCESSING II Sponsored by the Joint TMSISME AIME HydrometallurgylChemical Processing Committee Tuesday, February 16, 1985 2:30 p.m. Session Chairpersons: Patrick R. Taylor, Department

Senate Suite Sheraton Centre of Mining E~gineer:

ing and Metallurgy, University of Idaho, Moscow, Idaho 83843; James L. Hendrix, Department of Chemical & Metallurgical Engineering, University of Nevada, Reno, Reno, NV 89557

(2: 30

The ollerall respective reactions for these two mechanisms <1re: CuFeS z + CuS0 4 + 2CuS + FeSO 6CuS + 3CuS0 4 + 4H 0 + 5 Cu 4 S

+

(I) (2)

4H SO

Sulfide ion was proposeJ to be tfie Brate c~ntiolling species for the product layer d'iffusion mechanism. The effects of particle size. temperature, pH, cupric ion concentration, and ferous ion concentration on the leaching kinetics were examined. The higher temperatures of the autoclaves greatly enhanced the reaction rate due to the high·actlvation energies. Additions of ferrous sulfate were found to alter the product layer structure slightly which then enhanced the sulf 1'\" diffusion and il('celf'rated the reaction.

(4:20 p.m.) "OXYGEN PRESSURE LEl\CllING or GOLD ORES WITH l\ NOVEL MIX!';R," lJy Lawrence M. Litz, LilKle Div., Union Carbide Corp, 'l'urrytown, N.Y.,

r. m.)

.:lnu John E. Litz, lIazen Research, Inc., C;olden, CO.

PREVENTION OF AGGREGATE FORMATION DURING OXIDATION PRESSURE L~:ACHING: A. E. Petersen, Salt Lake City Research Center, BuHlnes, U.S. Department of the Interior, 729 Arapeen Drive, Salt Lake City, UT.

Sulfur-bound aggregates, formed during oxidation pressure leaching of pyritic concentrates, can caU8e severe operating difficulties. This paper describes research conducted on a' laboratory scale which resulted in a selective pressure-leach technique that solubilizes the rnetA..l values for recovery and prevents aggregate formation. The method primarily involves (1) avoiding pyrite overgrinding and (2) leaching with low partial pressures of oxygen. Data are presented for cobal t ite-bearing concent rates. Over 90 pct of the cobal t and nickel were extrlicted, leaving unaggr~gated residues containing iron arsenates and pyrite.

Laboratory and pilot scale oxyyen pressure leachinq tests of refractory gold orcs have been made usinq the Union Carbide Advanced Gas Reactor. Datu is presented which proj ects higher reaction rates dt lower mixinrJ power requi rements and at lower pressures and temperatures than is required in conuncrcii,ll .:lutoclaves utilizinq conventionul mixers. The imporved I)erformuncc is ilttributed to iln increilsed volumetric mixin(J intensity within the unit's droJ.ft tube. Other positive feoJ.tures of t.his new design arc the avoidance of oxyqen spoJ.rqer below the liquid surfoJ.ce and oJ. very high oxygen utilizution factor.

KINETICS II: NONFERROUS SYSTEMS Sponsored by the TMS Physical Chemistry Committee and the PTDlISS Tuesday, February 26, 1985 2:30 p.m.

(2:55 p.m.) KIH..!.L'IC~~

l;F l.i.G,..,JlLU L-...A.CHTL:~ LEO' JF1:..L~i(I L'i:: COrCETi'fRA.c;:;: 4 Venkatachalam =el S.::. Jomc.n, Clept. of Hetallurgic::l-Tngg.-;-T:I'"Y., Bombay

Dominion B Sheraton Centre

Session Chairmen: T. DebRoy, Det. of Materials Science and Engr., The Pennsylvania State U., University Park, PA; H.Y. Sohn, Dept. of Metallurgy and .Metallurgical Engr., U. of Utah, Salt Lake City, UT 84112

The kin" tic3 of dissolution of sphaleri te concentrate

in H2:JJ4 under an overpressure of oXY,ren has been studied. l'!1e effect of tem;>eruture, oxy::err nartial uressur~, U!j. ~ution, 1-12::04 corlcentr;~tic)l1, percent solids, par,~cle ;j~"e of concentrate and ad,lition of ferric su19hnte on the percent8/e of extr~ction of zinc has been investi guteu. 1'emperOoC, the a9:oarent activ!'tion enerry is found to be 6.2.52 kcal per mole. About 95·/. zinc cO\.del be leached in 4.5 ho~r::;. 'file kinetics and mechanism of ~eaching has been cl~::,;cll~sed. (3:2Q p.m.)

AQUEOUS PRESSURE OXIDATION OF ARSENOPYRITE: V. Papanqelakis and G. P. Demopoulos, Deot. of Mining & Met. Eng~., McGill Univ., 3450 University St., r~ontreal, Quebec H3A 2A7, Canada Arsenopyrite along with pyrite are the most common host minerals of refractory gold. To effect gold recovery from these sources the mineral structure has first to be broken down - altered. Oxidation roasting used to be the principal method applied for the purpose of rendering gold accessible to subsequent cyanidation. However due to environmental restrictions pressure leachinq aopears to be the best alternative pretreatment process for refractory gold especially for that associated with arsenic containing materials. In a number of these refractory ores, qold has been found to be specifically associated to arsenopyrite and not to pyrite. This of course opens the interesting possibility for selective aqueous oxidation of the fonner with apparent economic benefits. Previously nublished data indicate in fact that.o~idation 0 arsenooyrite can be affected under relatlvely ~l~d condltlOns «120 C) in contrast tg pyrite wh~re strong oXldlzlng condltlOns are required (180-200 C). In view of the qreat potential pressure leaching has as pretreatment process for auriferous refractory arsenical ores a detailed study of the aqueous oxidation of arsenopyrite was undertaken, which constitutes the subject matter of this presentation. The kinetics and products fonned under various pressure leaching conditions will be described and pertinent high temperature Eh-pH dia~rams wi 11 also be presented.

6

(3:45 p.m.)

(2:30 p.m.) REDUCTION OF CUPROUS SULFIDE (CU2S) WITH H2 AND HZ-He MI XTURES: Hamld Bagherl and Y. K. Rao, Department of Matenals Science & Engineering, FB-IO, University of Washington, Seattle, WA 98195. The kinetics of reduction of CU2S fines with H6 and H2-He gas mixtures were determined in the range 450-1040 C using thennogravimetry. The study with H2-He gas mixtures was 1 imited to three temperatures: 450, 500, and 550°C. The rate constant values derived from the experimental results were plotted in an Arrhenius manner. At moderate temperatures (450-655°C) the activation energy for the reduct i on process was found to 13.9 kca limo 1e. At elevated temperatures, due to mass-transfer effects, the activation energy declines to 9.3 kcal/mole. The morphology of the copper product was examined by SEM. In the range 450-750°C, the copper product consisted of fibers and loops. But at higher temperatures (850-1020°C), sintered spongy copper was formed.

(2:50 p.m.) DEOXIDATION OF LIQUID COPPER BY INJECTION OF CARBON PARTICLES: Y. W. Chang. T. W. Chia, M. J. McNallan, Department of Civil Engineering, l'-Iechanics anti Metallurgy, University of Illinois at Chicago, P.O. Box 4348, Chicago, IL 60680 Oxygen can be removed from liquid copper by reaction with solid carbon particles. The kinetics of the process can be accelerated by the injection of inert gas to stir the melt and to remove the reaction products. An apparatus has been constructed in which approximately 20 kg of liquid copper can be reacted with a form of high purity, low reactivity carbon (DESULCO, ohtained from Superior Graphite Co.). Carbon particles are floated on the surface of the mel~, and the metal can be injected with gas or gas-particle mixtures. The effects of vC!-rying the flow rate of gas, the chemistry of the gas and the particle size of the carbon on the rate of deoxidation are described. This research is supported by the National Science Foundation under Grant ePE 81 15342.

Break (3: 10 p.m.)

(3:55 p.m.)

TEMPERATURES: R. D. Peterson and M. E. Wadsworth, DepartJllent of Metallurgy, University of Utah, Salt Lake City, Utah

VAPORIZATION OF SnO FROM SILICATE MELTS*: A, Patankar, G.Simkovich and T. DebRoy, Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pa,

A hydrometallurgical approach to the conversion of chalcopyrite to various copper sulfide compounds has recently gained interest. A kinetic study of this conversion leaching reaction was ma.de at temperatures above 373 K (100°C) using autoclaves. A mixed kinetic model consisting of surface reaction control and product layer diffusion control was found to fit the experimental data.

The vaporization of stannous oxide from SnO-Si0 2 melts was studied in the temperature range lSOO-1600K. Rxperiments were conducted under helium, nitrogen and CO-C0 2 mixtures. The rates of vaporization of SnO were found to be proportional to the diffusivities of both the monomeric and polymeric form of SnD i~ the inert gases. The rate controlling step in the

CONVERSION OF CHALCOPYRITE TO COPPER SULFIOES AT ELEVATED

52 - TMS-AIME Annual Meeting Program vaporization was found to be the transport of the oxide vapors

(both monomeric and polymeric SoD) through the gas boundary layer even though the vaporization rates were insensitive to changes in the gas flow rate.

* Sponsored by the National Science Foundation Under Grant# CPE-B120B74. (3:30 p.m.) THE PHYSICAL CHEMISTRY OF THE REDUCTION OF A1203(S) BY CARBON, 1700-1900 0 C: R. J. O'Malley, Alcoa Technical Center, Alcoa Center, PA 15069; R. A. Frank and J. F. Elliott, Dept. of Materials Science and Engrg., Massachusetts Institute of Technology, Cambridge, MA 02139

MATERIALS ASPECTS OF SEMICONDUCTORS AND DEVICES II: MISCELLANEOUS TOPICS Sponsored by the TMS Ad Hoc Electronic Device Materials Committee Tuesday, February 26, 1985 2:00 p.m.

Princess Ballroom Sheraton Centre

Session Chairman: S. Mahajan, Dept. of Metallurgical Engineering & Materials Science, Carnegie-Mellon Univ., Pittsburgh, PA 15213

(2:00 p.m.) 'Surface Layer Spinodal Decomposition in Inl_xGaxAsyPl_y and

The kinetics of the reaction for the reduction of alumina by carbon is being studied. The experiment's variables are temperature, surface area of the alumina phase, activity of aluminuln, and partial pressure of carbon monoxide. The activity of aluminum is reduced by dissolving the product metal in a copperaluminum bath. The rate of the reaction is followed by the rate of evolution of CO, the loss in section of the alumina specimen, and the change in composition of the copper-aluminum bath. The liquid bath is stirred by the evolution of gas from the liquid metal-alumina interface, but gas phase reduction also occurs. (3:50 p.m.) REDUCTION OF CUPROUS SULFIDE WITH CO+C02 GAS MIXTURES IN THE PRESENCE OF LIME: M. Moinpour and Y. K. Rao, Department of Materials Science & Engineering, FB-10, University of Washington, Seattle, WA 98195. The reduction kinetics of cuprous sulfide with CO+C02 gas mixtures In the presence of lime are investigated in the range 850-1000°C "s i ng a thermogravimetric set-up. The effects of temperature, CO-partial pressure, and catalyst (K2C03) additions on the reduction kinetics are determined. The results are helpful in formulating the mechanism of carbothermic reduction of cuprous sulfide in the presence of lime.

Inl_xGaxAS Grown by Hydride Transport Vapor Phase Epitaxy. S.N.G. Chu, S. Nakahara, K.E. Strege, and W.D. Johnston, Jr. AT&T Bell Laboratories Murray Hill, New Jersey 07974 Composition modulation in Inl_xGaxP l-y quaternary and Inl..-xGaxAs ternary alloys are observed by TEM in layers grown on the (001) InP substrate by hydride transport vapor phase epitaxy A quasiperiodic fine contrast oriented along the [100] and [010] directions is found in all samples encompassing a composition range of 0.20 < x < 0.53 and 0.37 < y < 1. Contrary to the results of Lau;-ois-et al., complet; mi-;ing at compositions outside the miscibility gap predicted by thermodynamics for bulk c.rystals is not observed. Furthermore J TEM diffraction contrast experiments on the (110) cross-sectional view of planar and nonplanar expitaxial layers reveal a columnar structure oriented along the growth dire~tion. This observation together with the presence of fine scale composition modulations are consistent with the occurrence of surface spinodal decomposition.

(2:30 p.m.) EFFECTS OF COMPOSITION MODULATIONS ON ELECTRICAL PROPERTIES OF InGaAsP EPITAXIAL LAYERS: H. Launois and M. Quillec, Centre National d t Etudes des Telecommunications t 196 rue de Paris 92220 Bagneux, FRANCE.

(4: 10 p.m.)

lnxGal_xAsyPl_y epitaxial layers, emitting in the 1.2-l.5~m

KIIBTICS OF Cu 0 ,RSJUCTIOt, FRO}! LL/UI::J SUGS: V. L. Prabl:u and R. G. Reddy, onspt. of Chemical So Metallurgical l:ngrg., Hackay School of Hines, University of Nevada-Reno, Reno, NV 89557

grown at two temperature ranges, i.e., (i) 630-660 oC (set I)

Studies on reduction of CUO 5 from liquid secondary copper smelting slags were investigat~d. The experiments were performed under argon atmosphere in a resistance heated furnace using a graphite lined alumina crucible. Reduction kinetics of CuO were studied for temperature range from 1500 to 1600 k and p 5 to 8.0 pct. initial copper oxide in the slag. The reaction kinetics follows first order with respect to concentration and are controlled by an interfacial chemical reaction. The calculated activation energy for the reduction process was 46.55 k cal/mole.

8

regime and lattice matched to (001) InP substrates, have been

and 740°C (set II), by liquid phase epitaxy.

The set I samples

exhibit lower Hall mobility than the set II.

We suggest that

this difference could arise from the absence of composition modulations in set II samples, but not in set I.

(3:30 p.m.) (4:30 p.m.) THE KINETICS AND MECHANISM(S) OF REDUCTION OF NICKEL OXIDE IN LIQUID SLAG BY CARBON IN IRON. K. Upadhya* and 1.0. Sommerville,t ;':Department of CEMM, University of Illinois at Chicago, Box 4348,

Chicago, IL 60680 and tDepartment of Metallurgica! Engineering, University of Toronto, Toronto, Canada. The reduction of nickel oxide in dilute solution in CaO-Al203-Si02 slag by carbon dissolved in iron was investigated in a system which exluded graphite. The variables studied to elucidate the reaction mechanism were carbon content of iron', nickel oxide concentration in slag, slag/metal interfacial area and pressure inside the crucible. The results obtained are exp.lained by postLllating the existence of a gas fi 1m at the slag/metal interface. It is proposed that the fast reduction stage for nickel oxide takes place predominantly by an exchange reaction:

(NiO) + [Fe] = (FeO) + [Ni] (FeO) + [C] = Fe + CO(g)

(il (ii)

The exchange react ion (i) is thought to be mass transport controlled in the gas bubbled stirred slag phase. However, the rate controlling step for the reaction (i1) is a chemical reaction at the gas/meta I j nterface.

(4:50 p.m.) THE RATE OF FORMATION OF SiO(g) BY THE REACTION OF CO WITH SILICA AND SILICATE SLAGS:' B. Ozturk and R. J. Fruehan, Carnegie-Mellon University, Pittsburgh, PA. Silicon monoxide gas (SiO) plays an important role in silicon transfer in the blast furnace. !t has been speculated that the reaction mechanism for the reduction of silica in blast furnace type slags involves the formation of SiO as a gaseous intermediate. In the present work the rate of formation of SiO(g) by the reaction of CO with pure silica or silicate melts has been investigated. Using spheres of SiO Z for which the gas phase mass transfer conditions are clearly def~ned, it is found that the rate is controlled by a chemical reaction at the surface. The rate was independent of flow rate, of the dilution gas (Ar or He) and was significantly slower than calculated for mass transfer. Measurements have also been made on A1 2 0 3 - Si0 2 liquid slags.

ION IMPLANTATION DAMAGE AND SEMICONDUCTORS: J. Narayan, Carolina, Research Triangle Engineering, North Carolina

ITS ANNEALING PHENOMENA IN Microelectronics Center of North Park and Department of Materials State University, Releigh, NC 27650

This talk consists of two parts. In the first part, we discus'S the details of ion-solid interactions in semiconductors. Theoretical and experimental results on ion range and depc.1tited damage energy are presented, and the effects of ion implantation parameters and annealing phenomena are ex~ined. High resolution electron microscopy is shown to provide extremely useful information on the natl.lre and atomic structure of cascades, and the process of amorphization. In the second part, novel methods of annealing of ion implantation damage to recover electrical properties of semiconductors for advanced device applications are discussed.

(4:00 p.m.) THE ROLE OF THERMAL STRESSES IN DISLOCATION GENERATION DURING the LEC GROWTH OF GaA. and InP. A.S. Jordan, AT&T Bell Laboratories, Murray Hill, NJ 07974. In contrast to Si, Czochralski growth of low dislocation density single crystals of GaAs and InP cannot be accomplished exclusively by means of suitable seeding and necking procedures. Modeling of liquid encapsulated Czochralski (LEC) pulling together with experimental observations lends strortg support for the view that excessive thermal stresses are the predominant source of dislocation generation in compound semiconductors. Brief outline of the analytically tractable quasi-steady state heat transfer! thermal stress model will be pre~ented. It will be shown that by employing realistic estimates for the required high temperature physical property values (thermal conductivity, elastic constants, critical resolved shear stress, etc.), dislocation density contour maps and the threshold for defect fomation, which are in accord with experimental findings, can be determined. The promising practical avenues to suppress dislocation generation in these materials via impurity hardening and temperature gradient reduction are consistent with the theoretical predictions.

TMS-AIME Annual Meeting Program - 53 MECHANICAL BEHAVIOR OF RAPIDLY SOLIDIFIED MATERIALS IV: Titanium Alloys, Intermetallic Compounds, and Amorphous Materials Sponsored by the TMS Mechanical Metallurgy Committee and the ASM-MSD Flow and Fracture Activity Tuesday, February 26, 1985 2:00 p.m.

Regency Foyer Sheraton Centre

Session Chairmen: J. C. Williams, Carnegie-Mellon University, SChenley Park, Pittsburgh, PA 15213; H. Kimura, The Research Institute for Iron, Steel, and Other Metals, Tohuku University, Sendai, Japan

that undergo a eutectoid decomposition of the beta phase were rapidly solidified into ribbons by melt-spinning. The RS ribbons were aged at sub-eutectoid temperatures for varying times. In order to compare the aging response of RS materials with that of the same alloys produced by ingot metallurgy (1M) approach, swaged alloy samples were solution treated in the beta phase field and similar aging treatments were. carried out. Microstructural characterization of both types of material was performed by optical microscopy, SEM, and TEM techniques. The age hardening behavior of the alloys was studied by measuring microhardness values.

(3:30 p.m.) (2:00 p.m.) MECHANICAL BEHAVIOR OF RAPIDLY SOLIDIFIED TITANIUM ALLOYS: * S. M. L. Sastry, T. C. Peng, and J. E. O'Neal, McDonneil Douglas Research Laboratories, St. Louis, MO 63166. The major benefits of rapid solidification processing of titanium L loys demonstrated thus far include the formation of segregationless supersaturated solid solutions with Si, Ni, B, C, and rare earth element additions, large volume fractions of uniformly distributed, fine « 0.1 ~m) incoherent dispersoids with rare earth element and rare earth oxide additions, novel alloy mixtures with Li and Mg additions, snd fine grains. These microstructural modifications have been found to produce large increases in modulus and strength in several titanium alloys. The presentation will review the formation of the beneficial microstructures in cotmnercial pure Ti, as well as binary, ternary, and quaternary titanium alloys and the mechanical properties of different titanium alloys as influenced by the unique microstructural features resulting from rapid solidification. *This review was prepared under the McDonnell Douglas Independent Research and Development program.

STRUCTURE AND PROPERTIES OF RAPIDLY SOLIDIFIED INTERMETALLIC COMPOUNDS: I. Baker and E.M. Schulson, Thayer School ov Engg., Dart-

1!10uth Coli ege, NY 03755; N. S. Sto 1off, Mats. Engg. Dept., Rensselaer Poly tech. Inst., Troy, NY 12181 The application of various rapid solidification techniques to intermetallic compounds is reviewed. Melt-spinning has been employed for Ni-Al-X alloys which fom metastable L12 type superlattices, as well as for Ni Al+B, feAl, NiAl and dispersion strengthened Fe 3Al and Ti3Al. The arc-hammer technique has been applied to several long range ordered alloys of type (Fe,Co,Ni)3V as well as to Ni 3Al+B. Microstructures and mechanical properties of these alloys are described. Several aluminides and Ni Mo also have been prepared by rapid solidification of powders. Microstructural studies of the rapidly solidified alloys, utilizing optical microscopy, X-ray diffraction and both scanning and transmission elec tron microscopy are reviewed. The relationship between and structure of rapidly solidified powders and the mechanical properties of consolidated polycrystalline aggregates will be discussed.

(4:00 p.m.) MECHANICAL BEHAVIOR OF RAPIDLY SOLIDIFIED MATERIALS: Davis, Allied Corporation, Morristown, NJ 07960.

(2:30 p.m.) A STUDY OF MECHANICAL BEHAVIOR OF Ti-Al(Sn)-La AND Ti-Al(Sn)-Er ALLOY SYSTEMS.' C.S. Chi and S.H. Whang, 3'11 Mugar, Barnett Institute, Northeastern University, Boston MA 02115 Recent studies by different authors show that at high temperatures, Ti alloys containing La Or Er exhibit ex·cellent mechanical strength and stability resulting from stable dispersoids. However, the mechanical properties that differentiate the two alloy systems are not known. In present experiments, splat foils, ribbons and bulk alloys consolidated by HIPing will be prepared. Age hardening behilvior of these alloys will be investigated in conjunction with mic/,ostruct·ural characteristics by TEM, which includes the structure identification of dispersoids at this stage. Effects of high temperature annealing will be studied by hot hardness tester and TEM. All results frOm different types of specimens will be discussed with respect to thermal history and particle coarsening.

Lance A.

Metallic glasses have been the subject of curiosity and fascination for slightly over 20 years now. Early research efforts focussed on the glass formation process, on investigations of structure and on thermal transformation behaVior. With the availability of ribbon-like "samples," studies of mechanical properties were facilitated. The mechanical properties of glassy alloys are of interest on a number of counts. For example, by contrast with the properties of inorganic glasses and crystalline metals; they provide insight into the mechanics of materials, in general. Some of their properties are unique: in particular, they behave as elastic-perfectly plastic materials and, hence, provide a "test-bed" for model mechanics studies. Mechanical behavior dictates the need for fine control of the ribbon making process; the occurrence of inhomogeneous deformation renders post-quench cold forming processes ineffective. Finally, the performances of metallic glasses in magnetic applications depend on the control of magnetoelastic properties. Each of these subjects will be considered, as we review the fundamental mechanics of glassy alloys.

'Research sponsored by the Office of Naval Research.

(4:30 p.m.) (2:50 p.m.) MICROSTRUCTURE AND MECHANICAL PROPERTIES OF RAPIDLY SOLIDIFIED TiAl-Er ALLOYS: D.G. Konitzer and H.L. Fraser, Dept. of Metallurgy and Mateials Research Laboratory, Univ. of Illinois, Urbana, IL. Alloys taken from the Ti-Al-Er system (up to a composition correspondi ng to Ti 3A 1) have been rapi dly sol di fi ed us i ng two processing techniques, namely melt-spinning and laser spin atomization. The microstructures of these materials have been characterized and it has been found that it is possible to develop a refined dispersion of Er203 particles by subsequent heat treatment. The ribbons are reduced to particular by use of rotating knife blades and SUbsequently consolidated by hot isostatic pressing. The results of mechanical tests at ambient temperature and 750·C will be presented and discussed in terms of the microstructure of the rapidly solidified alloys.

(3:10 p.m.) AGE HARDENING BEHAVIOR OF RAPIDLY SOLIDIFIED TITANIUM-EUTECTOID FORMER ALLOYS: S. Krishnamurthy and F. H. Froes, Air Force Wright Aeronautical labOratories, AFWAL/MLLS, Wright-Patterson AFB, OH '15'133; D. Eylon, Metcut-Materials Research Group, P.O. Box 33511, Wright-Patterson AFB, OH '15'133; I. Weiss, Wright State University, School of Engineering, Dayton, OH 'IS'I3S The benefits of rapid solidification (RS) processing of titanium-base alloys containing eutectoid forming additions is being Investigated, Ti-Cr-AI and Ti-Cu alloys with compositions

SHEAR BAND REVERSAL AND ANNEALING EMBRITTLEMENT OF ANi-BASE AMORPHOUS ALLOY:* Xingguo Cao** and J. C. M. Li, Materials Science Program, University of Rochester, Rochester, 11Y 14627. Shear bands produced by bending before annealing could be reversed if isothermally annealed or continuously heated before the onset of embrittlement. The activation energy for the onset of embrittlement is 69-72 kcal/mole similar to that of crystallization, 67-78 kcal/mole, if the latter is evaluated at the same x-ray first peak height. The activation energy of crystallization based on Kissinger plots of DSC data is erroneous, since samples at the onset or peak of crystallization in the thermogram do not have similar x-ray first peak heights. It seems that whatever structural modification is inside the shear bands is stable during annealing until embrittlement and that the embrittlement is related to the inCipience of crystallization.

*Work supported partially by DOE through DE-AC02-76ERO-2296. Amorphous alloys were supplied by Allied Corporation through L. A.. tlavis. **Visiting scholar from Luoyang Institute of Technology, Luoyang, Henan, Ch ina.

54 - TMS-AIME Annual Meeting Program (4:50 p.m.)

(3:30 p.m.)

EMBRITTLEMENT OF METALLIC GLASSES: T. W. Wu and F. Spaepen, Division of Applied Sciences, Harvard University, Cambridge, MA 02138. Ductile fracture of metallic glasses is accompanied by extensive local plastic flow. Brittle fracture is promoted by a number of factors: composition, low temperature, high strain rate, and, most characteristically, annealing (below the crystallization temperature). We will present the results of an extensive study on the embrittlement of amorphous Fe79.3B16.4Si4.0CO.3, including bending tests (both at elevated and low temperatures), tensile tests, fractography and x-ray small angle scattering. The bend tests were ideally suited for determining the ductile-to-brittle transition temperature, TD-B. The combination of tensile testing and fractography allowed us to observe the ductile-to-brittle transition as a function of strain rate. The x-ray small angle scattering showed no measurable change in microstructure corresponding to the embrittling annealing conditions; only when small crystals were known to be present was a change in small angle scattering observed. The relation between the embrittlement well characterized relaxation phenomena in metallic glasses, such as a large viscosity increase, will be discussed.

MECHANICAL FAILURE MODES IN NUCLEAR MATERIALS II: Hydrogen and Environmental Effects Sponsored by the TMS-ASM-MSD Nuclear Metallurgy Committee Tuesday, February 26, 1985 2:00 p.m.

Monarch Suite Sheraton Centre

ENVIRONMENTALLY-ASSISTED CRACKING OF NUCLEAR POWER PLANT COMPONENTS

R.L. Jones, J.T.A. Roberts, and J.D. Gilman, Electric Power Resear. Institute, Palo Alto, CA. Corrosion cracking of structural components in light water reactors has caused significant forced outages with associated high costs for repairs and replacement power. Typically, materials-related capacity factor losses have averaged 5% per plant in recent years. Very few components have escaped some form of corrosion damage; cracking has been observed in fuel and control rods, piping, valves, he~t exchangers, pumps, and turbines. This paper provides a review of environmentally-assisted cracking in light water reactor componeqts and identifies remedial actions based on stress, environment, and material improvements.

(4: 15 p.m.) MECHANISM OF STRESS CORROSION CRACKING OF SENSITIZED INCONEL ALLOY 600 IN SULFUR BEARING ENVIRONMENTS. R. Bandy and R. L. Sabatini, Brookhaven National Laboratory, Upton, New York. ',fhe mechanism of stress corrosion cracking (see) of sensitized Inconel 600 (nominally 75% Ni, 15% Cr, 8-10%Fe) is investigated in 1.3% boric acid solution containing small amounts (ppm level) of sodium thiosulfate (Na2S203) or sodium tetrathionate (Na2S406). Results indicate that sec occurs only when the sulfur concentration exceeds an apparent threshold level, which however, varie~ with the severity of the test methods such as, slow strain rate, constant load or constant deflection tests. The see is intergranular and occurs only when the sensitizing heat treatment leads to chromium depletioq along the grain boundaries below a critical value as determined by analytical electron microscopy. The role of pH and the electrochemical potential on the crack propagation rate is described. At certain potentials, the crack propagation rate 1s very high (-llJm/s or higher) perhaps due to a mechanical component of crack growth.

Session .Chairmen: J. R. Weeks, Department of Nuclear Energy, Brookhaven National Laboratory, Upton, New York 11973; J. C. Bilello, Department of Materials Science, State University of New York, Stony Brook, NY 11794

(2:00 p.m.)

MECHANISMS OF HYDROGEN EMBRITTLEMENT IN MATERIALS OF INTEREST TO THE NUCLEAR INDUSTRY: H.K. Birnbaum, University of Illinois, Department of Metallurgy and Mlnlng Engineering, Urbana, IL. Hydrogen embritt1ement and the related phenomena of stress carras i on crack i ng has been, and cant i nues to be, a problem in many areas of the nuclear industry. The premature fracture at low stress levels which characterizes these environmental phenomena occurs in hydride forming material (eg. alloys based on Zr, Ti, and the Group Vb metals) and in non-hydride forming systems such as the stainless steels, Ni based alloys, and high strength steels. Recent research has clearly shown that while the phenomena which characterize this type of failure are similar in the different types of systems, the mechanisms of hydrogen related fracture are very di fferent. These recent results and the insights they have engendered will be reviewed. It will be shown that the solutions to problems of envi ronmenta 11y related fracture wi 11 have to be rather different in the various types of systems.

(2:45 p.m.) KINETICS OF HYDROGEN-INDUCED SLOW CRACK GROWTH IN STAINLESS STEELS:"T.P. Perng and C.J. Altstetter, Dept. of Metallurgy, Univ. of IllinoIs, Urbana, IL. 61801 Gaseous hydrogen- induced s I ow crack growth behav i or in aus ten it ie, ferritic, and dual phase (a/y) stainless steel alloys was investigated over the temperature range 0-200 0 C. The experiments were conducted in pure hydrogen, hydrogen/argon, and in the presence of water vapor. The partial pressure of hydrogen varied from 10 kPa to 100 kPa (0.1 "'2.0 atm). In general, typical three-stage crack growth behavior was observed. Over a certain temperature range the threshold stress intensity (Kth) values and the crack growth rates in the second stage (da/dt) II were found to increase with temperature. The presence of water vapor appeared to block the entry of hydrogen and thus reduced the values of (da/dVII but had 1 ittle or no effect on the Kth values. Increasing hydrogen fugae i ty increased (da/dt}11 and reduced the Kth va lues. Separate gas-phase hydrogen permeation experiments for the same materials with pure hydrogen or hydrogen/water vapor were also carried out. The crack propagation kinetics will be compared and rationalized with the diffusion and permeation parameters of these alloys.

"Work performed under NSF Grant DMR-83-03421.

0.15 p.m.)

Break

METALLURGY OF JOINING OF MATERIALS IV Sponsored by TMS Physical Metallurgy and Solidification Committees Tuesday, February 26, 1985 2:00 p.m.

Washington Suite Sheraton City Squire

Session Chairman: R. Schaefer, National Bureau of Standards, Washington, DC 20234

(2:00 p.m.) EPMA/AEM STUDY OF MORPHOLOGICAL STABILITY OF ~-V PHASE INTERFACES IN Ni-Cr-Al ALLOYS: S. M. Merchant, M. R. Notis and J. 1. Goldstein, Department of Metallurgy and Materials .Engineering, Lehigh University, Bethlehem, FA 18015 An understanding of interfacial stability in qiffusion-bonded s tr~c tures is importan t in order' to obtain integral mul tiphase produc ts. Requirement of such knowledge is cri tical in the formation and/or degradation of aluminide coatings on superalloy components that are formed by reaction diffusion between the coating ~nd the substrate. The Ni-Cr-Al system provides a basis to simplify the complex chemistry of most Ni-based superalloys. In this investigation, the morphological stability of interfaces in solid-solid diffusion couples consisting of a cOlIIllon terminal ~ (Ni-50 alo Ai) end member and a series of V (pure Ni and Ni-Cr) alloys isothermally annealed at 1150 o C, was examined using optical metallography and electron-probe microanalysis. The transition from a stable or planar to an unstable or non-planar interface with a y end member at_Ni-40 a/o Cr, was followed using measured diffusion paths, interface compositions and microstructural information gathered about the appropriate. interfaces. Pre I iminar.y results from diffusion couples annealed for short periods of time and analyzed using analytical electron microscopy will also be discussed.

(2:30 p.m.) WELDING OF AUSTENITIC ALLOYS FOR CRYOGENIC SERVICE E. Dalder, Lawrence Livermore National Laboratory, P.O. 1/5511 (L-643), Livermore, CA 94550 ABSTRACT UNAVAILABLE

TMS·AIME Annual Meeting Program. 55 (3:00 p.m.) THE WELDABILITY OF RARE-EARTH TREATED TYPE 304L AUSTENITIC STAINLESS STEEL: Ernest F. Nippes and Doreen J. Ball. A comprehensive study of the solidification behavior, hot-cracking susceptibility, and weld penetration in autogenous GTA weldments of a well-prepared set of nine heats of Type 304L austenitic stainless steel was undertaken. In particular, the effect of rare-earth additions on hot cracking was investigated. The Varestraint test was used to study the hot-cracking susceptibility of the Type 304L heats which were investigated. Utilizing 100% argon shielding~ hot cracking was eliminated in welds of heats containing either extremely low-sulfur contents or optimum levels of rare-earth additions which formed rare-earth sulfides. The optimum rare-earth contents were determined to be in the range of 0.53 to 0.69 weight ratio of rare earths to sulfur. The Marangoni effect appeard to control the depth/width ratios of weldments by controlling the direction of weld-pool flow. Weld pools with low, concentrations of surface-active elements (5,0) exhibit a negative surface-tension gradient, an outward weld-pool flow from under the elec trade to the pool edge, and a low depth/width ratio. Thus, weldments which contained the optimum rare earth to sulfur ratio for minimizing hot cracking and good weld-pool depth/width and volume characteristics.

(3:30 p.m.) SENSITIZATION DEVELOPMENT IN THE HEAT AFFECTED ZONE DURING WELDING OF AUSTENITIC STAINLESS STEEL:* S.M. Bruemmer, B.W. Arey, R.E. Page, and D.G. Atteridge, Pacific Northwest Laboratory, Richland, WA. Austenitic stainless steel may become sensitized and susceptible to intergranular stress corrosion cracking during welding. Degree of sensitization measurements have been performed using the electrochemical potentiokinetic reactiviation (EPR) test as a function of distance from the weld fusion line on several instrumented 14 in. and 24 in. diameter pipe welds. Heat affected zone sensitization will be correlated to measured temperatures and s trai ns on a pass- by-pass bas is. A model will be presented for the prediction of heat affected zone sensitization as a function material composition, initial condition and thermomechanical history. Model predictions will be compared to experimental data. *Work sponsored by the Materials Engineering Technology Division, U.S. Nuclear Regulatory Commission.

rate constant was proportional to flow rate and the substrate concentration in the reactor varied with influent substrate concentration. The model allowed prediction of metabolic constants and included terms for both constant and growth rate dependent maintenance energies.

(2:55 p.m.) MICROBIAL COAL DESULFURIZATION: J. Murphy, E. Reistenberg, D. Marek, R. Mohler, C. Rischeid and D. Skidmore, Dept. Chemical Engrg., Ohio State Uniyersity, Columbus, OH 43210. Microbial desulfurization is a promising method for pre-combustion sulfur removal from coal. The technical and economic feasibility of the process were investigated in this work, using thermophilic bacteria (Sulfolobus aCidocaldarius) to leach sulfur from finely ground coal. Both batch and semi-batch operations, using aerated, thermal, acidic coal slurries, were tested. simulation of large scale processes involved using non-sterilized slurries with no added nutrients. Flow conditions, temperature variation and dilution were studied. Experiments were also conducted to investigate a method for water clean-up after microbial leaching by using aluminum, calcium and iron ions for sulfate precipitation. After cleaning, the liquor conformed to environmental standards.

(3:20 p.m.) BIOTECHNOLOGY IN THE PROCESSING OF GOLD: Yosry Attia. John Litchfield, and Luther Vaaler, BATELLE, Columbus Laboratories, 505 King Avenue, Columbus, OH 43201. The past experience with organisms in processing gold is reviewed. The use of microorganisms for liberation of gold from sulfide ores as a substitute for fine grinding is discussed. The possibility of accumulation of gold from solutions, such as gold from cyanide solutions, is explored as a potential replacement for such processes as carbon-in-pulp or ion exchange. The improvement in engineering technology and kinetics needed to scale-up from laboratory experiments to production scale are outlined. Cost estimates are presented showing that biotechnology can result in improved profitability for the industry.

(3:45 p.m.)

(4:00 p.m.) A STunV OF HFAT-AFFFCn:n

zn~F CR.~CKING

IN CAST ALLOY 718:

Y. L.

Tsay and W. A. Baeslack III, Department of Welding Engineering, The Ohio State University, Columbus, OH 43210 Heat-affected zone hot cracking in cast Alloy 718 has been studied via the Spot Varestraint test and hot ductil ity testing using a Gleeble 1500 System. Sensitivity to HAl hot cracking is correlated with data obtained for identically-tested wrought material and with the results of previous studies. Detailed analysis of the initial and as-tested cast microstructures using opti ca 1 and el ectron mi croscopy/ana 1ys is techni ques i ndi cate that a significant enrichment of niobium at grain boundaries promotes liquation cracking. Origins for this enrichment in the cast material appear to be the liquation of Laves phase and the solidstate dissolution of carbides, possibly enhanced by grain boundary mobility. Crack enhancement due to the constitutional liquation of carbides has not been confirmed in the cast alloy. This work was supported by the General Electric Aircraft Engine Business Group, Evandale, OH

MICROBIOLOGICAL EFFECTS ON MET ALLURGICAL PROCESSES II Sponsored by the TMSISME HydrometallurgylChemical Processing Joint Committee and the TMS Physical Chemistry Committee Tuesday, February 26, 1985 2:30 p.m.

Commonwealth Suite Sheraton Centre

Session Chairmen: J. A. Clum, Chern. & Met. Engr., U. Alabama, University, AL 35486, and L. A. Haas, Twin Cities Res. Ctr., U.S. Bureau of Mines, Minneapolis, MN 55417

(2:30 p.m.) KINETICS OF FERROUS IRON OXIDATION BY ATTACHED BACTERIA: Paul L. Wichlacz, EG&G Idaho, Inc., Idaho Falls, Idaho 83415. --The kinetics of ferrous iron Fe(II) oxidation by bacteria were studied in bench scale rotating biological contactors (RBC). Oxidation efficacies of better than 80% were obtained over the range of Fe (II) mass loadings tested (0.14 to 2.34 mg Fe (II) / cm 2 /hr). The amount of oxidation and the rate depended on a combination of influent and bulk fluid Fe(I!) concentration, as well as flow rate. A model describing attached bacterial growth and oxidation rate as a saturation function of substrate utilization was developed and tested. The maximum oxidation

A STUDY OF A PROPOSED DUMP LEACH OPERATION AT BOUGAINVILLE COPPER LTD. - PAPUA, NEW GUINEA: A. Bruynesteyn. B.C. Research, Vancouver, B.C., canada, and P. Piercy, Manager Milling, Bouga1nville Copper Ltd., Papua, New Guinea The paper describes the results of a field study designed to evaluate the potential for a commercial dump leaching operation as well as a subsequent pilot plant testing program carried out to evaluate the leaching characteristics of the prevalent Panguna Andesite and Biotite Grandiorite leach ores. The paper discusses how the results of the pilot tests were used to evaluate the proposed dump leach process.

(4:10 p.m.) MICROSIAL EFFECTS ON IN SITU LEACHING: Steven E. Follin, Twin Cities Research Center, U.S. Bureau of Mines, Minneapolis, MN, Marylynn V. Yates, Dept. of Microbiology and Il1'IT1unology, Univ. of Arizona, Tucson, AZ. James A. Brierley and Corale L. Brierley, Advanced Mineral Technologies, Inc., Socorro, NM 87801. In situ leaching to recover uranium from low-grade deposits in sandstone formations can only be effective if the formation retai ns its permeabil i ty duri ng 1each i ng. To invest i gate the hypothesis that leaching-stimulated microbial growth can cause plugging, samples from well casings and submersible pumps were obtained from four in situ mining sites. Chemical and microbiological analyses were performed. Bacillus species. micrococcus species, pseudomonads. and xanthomonads were i sol ated from these samples. A mixed culture of these organisms inoculated into a uranium core being leached in the laboratory caused a substantial decrease in permeabil ity. Injection of hydrogen peroxide restored the permeability to its initial value. These results suggest that periodic injection of hydrogen peroxide into production wells may ~~~~~ii~~~robial plugging in wells and the immediate surrounding

(4:35 p.m.)

Discussion

56 - TMS-AIME Annual Meeting Program MICROSTRUCTURE PROPERTY RELATIONSHIPS TMS-AIME General Abstract Session Tuesday, February 26, 1985 2:00 p.m.

Dominion A Sheraton Centre

Session Chairman: R. J. Arsenault, Metallurgical Materials Laboratory Chemical Engineering Building, University of Maryland, College Park, MD 20742

microscopy and SEM have been ~mployed to document the structures before and after HIPing. In addition~ the HIPing on the nature and distribution of porosity has evaluated by photomacrography, standard stereological and high precision density measurements.

microeffect of been techniques

(3:20 p.m.) Effect of Particle Size Distribution on Sintering of Tungsten:,* B.R. Patterson, J.A. Griffin, V.D. Parkhe and S.M. Bonds, Department of Materials Engineering, School of Engineering, University of Alabama in Birmingham, University Station, Birmingham, AL

(2:00 p.m.)

35294

THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF THE REACTION ZONE IN THE AL-LJ ALLOY/ALUMINA SYSTEM: W. H. Hunt, Jr., Dept. of Metallurgical Eng. & Materials Sci., CMU, Pittsburgh, PA and D. J. Bray, Alcoa Tech. Center, Alcoa Center, PA.

The sintering behavior and microstructure of tungsten powder compacts have been found to vary Significantly with the width of the lognormal powder size distribution, In a, at constant mean powder size. Narrow size distributions (lna = 0.14) produce the most uniform pore structures and densify the most rapidly. The widest

The purpose of this work was to examine the microstructure and mechanical behavior of the metal-ceramic reaction zone phase often found in the Al-Li alloy/alpha alumina system, namely t-LiA10 2 , as part of an effort to study the overall mechanical behavi or in metal mat ri x compos ites. Thi s was approached from two points of view. One was the production of bulk t-LiA10 2 followed by microstructural analYSis and mechanical testing. A parallel series of experiments encompassed reacting the Al-Li ",ot.al and alpha-alumina ceramic to form in-situ reaction zones of ;orious thickness, then obtaining mechanical properties of the -psuHant composite. Comparison between the microstructures, ~prhanical properties, and failure modes of the bulk t-LiA10. ncd the (-LiA10 2 formed as an actual reaction zone product are ·raoe. The impact of the reaction zone mechanical behavior on that of an Al-Li matrix/alumina fiber composite is considered.

distributions (Ina

(2:20 p.m.) Drs:n"'-TIO~

DISTRIBUTIONS IN DEFORMED SiC/AI COMPOSITES'

and R. J. Arsenault, Metallurgical Materials Laboratory, '?~:.-:-:-:T..-.~ of Maryland, College Park, MD 20742 H.

T,

r,:-::-,:~:

A series of 0, 5, 20 V% sic/6061 AI alloy composites, containing platelet and whisker SiC, were divided into two -batches: 1. Annealed at 803 K for 12 hrs and furnace cooled. 2. Heat treated to T6. The samples were fractured in tension at room temperature. A series of slices were taken perpendicular to the tensile axis a.s a fune'tion of distance away from the fracture surface. In all cases the dislocation density was extremely high in the slice which included the fracture surface (10 13 cm- 2 ). In the 0 V% sample thE' density decreased with distance away from the fracture surfae'e, However, in the 20 V% sample, slices taken 0.3 mm, i.e. one slice thickness, away from the fracture surface had almost the same density as the undeformed samples. *This research supported by the Office of Naval Research under

Contract Nn. NOO0l4-82-K-0493.

(2:40 p.m.) DEFORMATION IN SiC/AI COMPOSITES DUE TO THERMAL STRESSES" Y. Flom, and R.J. Arsenault, Metallurgical Materials Laboratory, University of Maryland, College Park, MD ?07h2 Plastic strains and the extent of the plastic zone due to differential thermal expansion were experimentally determined in a AISiC composite. The combined plastic shear strain Yc s at the AlSiC interfl3.ce for furnace cooled, air cooled and queEc~ed samples was found to be 1.32%, 1. 23% and 0.99% respectively. Profiles of y were plotted vs. distance from the interface and compared wr~ftStheoretical distribution of effective strain E. Theoretical plastic zone radius p = 2.3 x (particle radius) was found to be slightly less than Observed. Plastic defonnation on heating half of the thermocycle was found to be at least equal to the deformation on cooling half. Gradual disappearance of the slip bands was observed on heating to high temperatures with then total vanishing around 773 K. AI-SiC bond strength was found to be one of the important factors controlling the degree of plast ic deformation arOlmd SiC during thermal loading. *This research was supported by the Office of Naval Research under

=

0.75 and 1. 0) sinter more rapidly than the

narrow d,istribution initially, but less rapidly during the later stages. The intermediate width distributions have the lowest densification rates at all stages of sintering. The above effects can be related to differences in the microstructural parameters among specimens with different values of In a.

'This research is suppqrted by NSF-DMR-8306261.

(3:40 p.m.) EFFECTS OF SPINNING AND CONSOLIDATION CONDITIONS ON MICROSTRUCTURES AND 'MECHANICAL PROPERTIES IN a-TI ALLOYS CONTAINING RARE EARTH METALS.- C.S. Chi, Y.Z. Lu and S.H. Whang, Barnett Institute, Northeastern University, Boston MA 02115. Recently, pilot scale melt spinning of Ti alloys has been d~veloped at Northeastern University. These melt spinning

processes are very effective in generating fine and uniform microstructure combined with increased solubility of novel solutes. oI-Ti alloys containing rare earth metals will be spun into ribbons and flakes under various processing conditions. These precursor materials will be conSOlidated through .HIPing and

hot extrusion.

Microstructural characteristics of precursor and

consolidated alloys will be studied by TEM with respect to spinning conditions and consolidation parameters. Effects of

these conditions and parameters on microstructural refinement and interface bond characteristics will be investigated. "Research sponsored by the Office of Naval Research.

(4 :00 p.m.) MICROSTRUCTURE REFINEMENT OF Ti-l0V-2Fe-3AI ALLOY BY LOW TEMPERATURE EXTRUSION: Y. R. Mahajan, Air Force Wright Aeronautical Laboratories, Materials Laboratory, AFWAL/MLLS, Wright-Patterson AFB, OH 45433; I. A. Martorell, Westinghouse Electric Corporation, Advanced Energy Systems Division, Box 10864, Pittsburgh, PA 15236; D. Eylon, MetcutMaterials Research Group, P.O. Box 33511, Wright-Patterson AFB, OH 45433; T. F. Broderick and F. H. Froes, Air Force Wright Aeronautical Laboratories, Materials Laboratory, AFWALIMLLS, Wright-Patterson AFB, OH 45433 Microstructural refinement for titanium alloy Ti-l0V-2Fe-3AI was explored using low temperature extrusion of hot pressed powder and wrought material. Billets were extruded at 540°C and 625°C. The as-extruded microstructure for both materials consists of very fine alpha precipitates in the matrix of fine beta with grain size of 1-2 ~m. The beta grains are surrounded by lenticular grain boundary alpha. The extruded samples were aged at various temperatures. The microstructures were examined using optical, SEM, TEM, x-ray diffraction, and microanalysis techniques. The resulting microstructures and properties will be discussed in detail.

(4:20 p.m.)

Contract No. N00014-82-K-0493.

NEW DIE CASTING ALLOY WITH HIGH DAMPING CAPACITY: r~~~~ and A.Sakono-oka, Mitsubishi Metal Corp. Central Research Institute, Ohmiya Japan

(3:00 p.m.) HIPING OF AI-Si ALLOYS:

C.C. Chama and P.R. Howell, Department

of Materials Science and

Engineering~

Penn State Univ., Unive,rsity

Park, PA Pores are one of the main defects present in castings. ThesQ pores degrade the mechanical properties of a casting even when present on a microscopic scale. In certain instances, porosityfree castings are needed for special applications. The most suitable method that has been proposed for reducing porosity in castings 1s HIPing (Hot Isostatic Processing). In this study, the effects of HIPing on the microstructure and macrostructure of two commercial AI-S1 alloys have been investigated. Alloys containing up to about 11% porosity have been HIPed at various combinations of temperature (520 and 530°C), pressure (10,000

to 20,000 psi) and HIP times (15 minutes to 2 hr).

Light

Zn-AI binary alloy at the eutectoid point has been known to have a high damping capacity, but it has not been utilized because of its low strength. Authors have developed Zn-AI alloys for die casting (Trade Mark Cosmal-Z) by alloying it with Si, CU and Mn to strengthen without lowering the inherent damping capacity. Among these ZM-II contains 22%AI and ZM-3 does 40%AI respectively. ZM-II has superior strength and damping capacity at room temperature and ZM-3 does at a little higher temperature as far as lOO°C. In addition both alloys have good castability in die casting, therefore thin walled die casting is possible in contrast to existing Al die casting alloys. The damping capacity has a tendency to increase with lowering .frequency and inceasing temperature.

TMS-AIME Annual Meeting Program - 57 (4:40 p.m.)

structures, lattice spacings and thermodynamic parameters) in nearly all of the binary systems based on Au. In connection with some of the systems there has been much research activity over the past 10 years related to specific features; for example, structures resulting from rapid quenching, or various ordering reactions, magnetic interactions or thermodynamics. Among these several systems appear to be of particular interest. The miscibility gap in the solid solution range of Au-Pt alloys is so close to the solidus boundary that the form of the liquidus boundary appears to be affected. In Au-Pb and Au-Bi systems, several of the equilibrium phases are likely to be unstable at low temperatures. Complex experimental results reported in Au-Ge alloys can be interpreted by suitable free energy considerations. Other systems of interest which will be discussed are Au-Rh t Au-Ru and Au-W.

QUASI TWO-DIMENSIONAL SOLIDIFICATION OF ZINC COATING DURING THE HOT-DIP GALVANIZING PROCESS: Yong-Wu Kim, Inland Steel Company, Research Laboratories, 3001 East Columbus Drive, East Chicago, IN. The surface quality of hot-dip galvanized steel 1s very much dependent upon its solidification behavior. In this study, the effects of bath composition, cooling rate, and nucleating agents on the solidification morphology of zinc coating during the hot-dip galvanizing process were investigated. Many unique characteristics inherent with this quasi two-dimensional solidification process are presented and discussed. These include: (I) a significant undercoaling to enable grains to grow at the interface between the coating and steel substrate, (2) the effect of the lead content in the spelter for the growth of spangle, (3) the effect of nucleating/cooling agents on the growth direction, and finally (4) many interesting surface structures of the galvanized steel.

(3:10 p.m.) THERMODYNAMIC ASSESSMENT OF THE IRON NOBLE-METAL PHASE DIAGRAMS. Lydon J. Swartzendruber, National Bureau of Standards, Gai thersburg, Maryland 20899

(5:00p.m.) SOLUTE STRENGTHENING AND PRECIPITATION KINETICS OF A1N IN Mo HSLA STEELS; D. Anderson and M.G. Akben, McGill University, Montreal, Quebec. ThE: effect of Al and N addition on thE: high temperaturE: flow behaviour of a series of four 0.071. C, 1.25i, Mn and 0.20k Si steels ....'as investigated. A plain carbon and a 0.20% Mo steel were tested as reference materials. To thE:: latter, 0.08% Al ",as added with 0.005 and 0.010~ N. The influence of (i) Al and Mo in solid solution and (ii) All\' precipitation on the dynamic recrystallization kinetics ~as studied.' To distinguish these effects, compression tests were carried out in the temperature range 875 to 92S D C at constant strain rates varying frOID 5 x 10- 5 to 5 X 10- 1 5- 1 • The precipitation kinetics of All\' at the t~o levels ~ere determined from the mechanical test data and are compared to those reported in the literature. The presence of Mo delays the onset of precipitation. This is attributed to the increased solubility of A1N in austenite due to the decrease in the activity coefficients N and probably Al as ~ell. ThE recrystallization retarding effect.s of Al and Mo in solution are about equal (per 0.1 at.. %) when added alone. They are less effective than h'o and Ii, but more than V. \<."hen Al and Mo are added jointly, there is a synersistic effect, poss'ible explanations of ~hich are discussed.

PHASE DIAGRAMS, ALLOY PHASE STABILITY AND THERMODYNAMIC ASPECTS OF NOBLE METAL ALLOYS IV: Assessment of Phase Diagrams Co-sponsored by TMS Committee on Alloy Phases, ASM Alloy Phase Diagram Data Committee and ASM-MSD Thermodynamics Committee Tuesday, February 26, 1985 2:00 p.m.

Versailles Terrace Sheraton Centre

Session Chairman: Y. A. Chang, Department of Metallurgical and Mineral Engineering, University of Wisconsin, Madison, WI 53706

binary systems are similar in that they all have a miscibility gap in the solid state. In Fe-Ag. the miscibility gap extends to a very high temperature in the liquid state. The predl cted differences in the interactions

of the noble metals with ir'on in the liquid and solid states will be discussed.

(3:45 p.m.) SYSTEMATICS OF THE BINARY RARE EARTH-SILVER AND ~OLD SYSTEMS:· K. A. Gschneidner, Jr., and F. W. Calderwood, Ames Laboratory, Iowa State University, Ames, IA 50011 The variation as a function of the lanthanide atomic number of the stoichiometries, melting and transformation pOints, crystal structures, and lattice parameters of the various intermetallic compounds forms the basis of a study of the systematics in the RAg and R-Au binary systems. The variation of a given property as a function of the atomic number of the lanthanide metal gives us Bome insight concerning the chemical and physical nature of the compound series being examined. In addition departures from a smooth regular variation suggests that a valence change may have occurred in the cases of Ce t Sm, Eu and Yb, or that a physical property value is in error. The use of systematics is quite important in the critical evaluation of the known phase diagrams, and for estimating data when no experimental phase diagram is available. *Supported by USDOE, Office of Basic Energy Sciences, Division of Materials Sciences, under Contract No. W-740S-ENG-82.

(4:20 p.m.) STABLE AND METASTABLE EQUILIBRIA AND THERMODYNAMIC PROPERTIES OF TITANIUM-NOBLE METAL SYSTEMS:' Joanne L. Murray, National Bureau of Standards, Metallurgy DiviSion, Gaithersburg, MD 20899

(2 :00 p.m.) CRITICAL EVALUATION AND THERMODYNAMIC MODELLING OF SELECTED COPPER BASED BINARY ALLOYS:" D.J. Cha~rabarti + and D.E. Laughlin, ++ +Alcoa Technical Center,' Alcoa Center, PA 15069; HDepartment of

Metallurgical Engineering and Materials Science, Carnegie-Mellon Uni versity, Pittsburgh, PA 15213 The relationship between the thermodynamic properties of alloys and their phase equilibria can be utilized for the critical

evaluation of, binary systems. We show how limited available experimental thermodynamic data' can be used to del' i ve the most likely phase boundaries in systems with conflicting reports.

In

cases where no thermodynamic data is available, the known phase diagrams can be utilized for thermodynamic modelling to derive

parameters for the different phases, which in turn can reproduce the phase diagram consistently. Comparisons of these parameters with known experimental data often indicate reasonably good agreement. Using these parameters the phase equilibria in unreported regions of the phase diagram can be predicted.

Analytical expressions which describe the Gibbs energy of phase formation for the iron noble-metal binary phases have been constructed by an evaluation of available thermodynamic and phase diagram information. These functions can be used to calculate the phase diagrams and successfully represent both the experimental phase boundaries and the exper'imental thermodynamic information. They can also be used to estimate the metastable extensions of the phase boundaries. The three

Finally, we

include a discussion of the effect of magnetiC ordering on miscibility boundaries. "This work was sponsored by INCRA and by the OSRD of NBS.

(2:35 p.m.) PHASE RELATIONSHIPS AND THERMODYNAMIC MODELING IN SEVERAL BINARY SYSTEMS BASED ON GOLD H. Okamoto and T.B. Massalski, Department of Metallurgical Engineering and Materials Science I CarnegieMellon University I Pittsburgh, PA 15213 Recently, we have completed a detailed evaluation of the phase diagrams and related ancillary data (such as metastable

Recent reassessments of the Ti-Cu. Ti-Ag and Ti-Au phase equilibria and thermodynamic properties will be presented and compared. Calculations of the stable phase diagrams from optimized Gibbs energy function~ will be presented, and they will be related to the metastable and constrained equilibria occurring in these systems.

"This work was jOintly supported by the Office of Naval Research and the Metallurgy Division of NBS through the Office of

Standard Reference Data.

58 - TMS-AIME Annual Meeting Program PHYSICAL METALLURGY OF ELECTRICAL STEELS II Sponsored by the TMS Ferrous Metallurgy Committee Tuesday, February 26, 1985 2:00 p.m.

Consulate Suite Sheraton Centre

Session Chairman: A. R. Marder, Research Department, Bethlehem Steel Corp., Bethlehem, PA 18016 (2:00 p.m.) Nt~

INf~R~~TION

eN

HIGH >'Chl',lABIlITY S5nak fVlishra, Ir,on & Steel,

The

form~tion

C.

DEVlLQP~tNT

TeXTURl

LRAI,~-UFiIlf,TllJ

D~rrr.Elnn*

&:

K.

I~

SILlCul~

l.ucke*,

R[GUL~H

AND

SHll.S

R&D Centr:-:o

for

Steol Authority of India, Ranchi-8:'4002 of th~ Go~s tExtur~ in Fe-3% 51 ~as been

stu~i~d using th~ crystallit~ urientRticln distribution functinn tEchnique. Textural chdnges throuqh vHrious ~tages of proce~sing have been invBstigatpd for st~els with MI'~ as well as with a cor:binal.iQn of MnS and AIN as grain ~r[J~,th inhibilor. In bath cases the genesis

of the final sharp cube-an-edge texturr see~s to ,lip in t~e qrains ~lready present i, the Goss posit inn in tre 5urfaCF layers of the hut-roJlpd strip. The major ~ifference in t~e mFchanisrr of Gass texturp formation in t~e two steels is with respect to the rrlationship between the strene,ths of the ~ OJ <001> end <1127 components t~rough succesRiv~ processing

1

t11:3-

}2Erat~i~~7~~s~.~,-~~~____~__~_~~~__~_____~~~~. *Irlstitut far AIIge~eine MetaJlkunde 2nd Meta]]~hysik A ...:chlon, r fiG.

(2:30 p.m.)

ORIGIN AND DEVELOPMENT OF THROUGH- THE- THICKNESS VARIATIONS OF TEXTURES IN THE PROCESSING OF GRAIN ORIENTED SILICON STEEL. M. Matsuo, Y. Suga, and T. Sakai, Nippon Steel Corporation, R&D Laboratori es, Japan. In the production of high penneability grain oriented silicon steel, through-the-thickness variations of texture in the hot rolled sheet make an important contribution to perfection of secondary recrystallization. In particular large grains at a depth of 20 to 25% of the thi ckness are though t to provi de for the source of potenti a 1 nuclei for secondary recrys ta 11 i zati on. Fonnation of the Goss orientation in the subsurface of hot rolled sheets has been studied by rolling in a high speed mill equipped with means for quenching at a given time as short as 10 ms. The Goss grains are found to originate from heav:y shearing defonnation due to the high friction in hot rolling and develop by a process of in situ recrystallization and grain growth. The effects of the inhomogeneous texture are followed in the subsequent process in tenns of providing source of the nuclei and preparing surroundings for growth of the viable nuclei.

(4:00 p.m.) THE STUDY OF DESULFURIZATION KINETICS IN GRAIN-ORIENTED 3% SHe: T. H. Shen, Allegheny Ludlum Steel Corporation Research Center, Brackenridge, PA 15014, U. S. A. The desulfurization kinetics in grain-oriented 3% SiFe have been studied by using the model proposed by Swift et a1. The model assumes the desulfurization is diffusion controlled and the sulfur is present as dispersed MnS particles. Some modification on the model in the second stage of the desulfurization has been made. The desulfurization experiments were conducted at temperatures ranging from 1171 °c to 899°C in a dry hydrogen atmosphere with the thickness of samples ranging from 0.325 mm to 0.138 mm. Since there are wide variations among the published sulfur solubility data in 3% SiFe, the theoretical calculations showed good agreement with the. experimental results only when the sulfur solubility data published by Brown was used. This is different from the solubility data used in Swift's calculation. The effect of an MgO coating on desulfurizatian has also been studied.

(4:30 p.m.) EFFECTS OF DECARBURIZATIDN AND NORMALIZING HEAT TREATMENTS IN BORON SILICON-IRON ALLOYS: H.G. Lee, H.B. 1m and Y.G. Kim, Korea Advanced Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul, J( orea To clarify the role of carbon in secondary recrystallization in boron silicon-iron alloys, heats containing from 0.024 to 0.07% C at the hot band stage were prepared. Complete secondary recrystallization and high magnetic induction were observed in the heats containing 0.04 and 0.05% C when normalized for 5 min in the temperature range from 600°C to 1l00°C. The heat with 0.024% C developed no secondary recrystallization. Hot bands containing 0.04 0.07% C initially, then, oxide decarburized to obtain hot bands wi th various amounts of carbon content. All the decl3rburized specimens developed strong (110)[001] texture, contrary to previously reported, and high magnetic induction. Thus it can be concluded that the carbon plays an importa:1t role in melting and solidifying process to develop strong (110)[001) texture in boron silicon-iron allo"/s. Possible role of carbon and the effect of heat treatment will be presented.

RECOVERY PROCESSES IN THE SECONDARY METALS INDUSTRY Sponsored by the TMS Copper, Nickel, Cobalt and Precious Metals Committee Tuesday, February 26, 1985 2:30 p.m.

Georgian Ballroom B Sheraton Centre

Session Chairmen: J. E. Hoffmann, Extractive Met., Exxon Minerals Co., 5630 Guhn J«I., Houston, TX 77040; S. D. Hill, Salt Lake City Res. Center, U.S. Dept. of the Interior, Bureau of Mines, 729 Arapeen Dr., Salt Lake City, UT 84108

(3:00 p.m.) FORMATION OF GOSS ORIENTATION NEAR THE SURFACE OF 3% SILICON STEEL DURING HOT ROLLING ; Y. SHIMIZU, Y. IIDA, U. NISHIIKE, Y. ITO, Research Lab. KAWASAKI STEEL Corp. Mizushima Kurashikishi, Japan. The influence of hot rolling reduction, rolling temperature rolling speed, lubrication and initial orientation on the formation of Goss orientation near the surface of 3% silicon steel was studied. Strong aggregation of Goss component was observed at the reduction of over 85% in any initial orientation. Stronger Goss texture was obtained in the specimen rolled at higher speed in the range of 6 SOm/min and at lower rolling temperature in the range of 800 1100 C. It was found that Goss orientation was formed not by recrystallization during hot rolling but by slip rotation near the surface. The high friction between roll and sheet characteristic to hot rolling was very important for this texture formation.

(3:30 p.m.) HIGH TEMPERATURE GRAIN GROWTH DURING SLAB REHEATING OF ORIENTED 3% Si-Fe MADE USING CONTINUOUS CASTING. J. W. Schoen, ARMCO Inc., Research & Technology, Middletown, Ohio 45043 Studies were made into the process behind the excessive grain growth which is observed in continuous cast slabs of both regular and high permeability oriented 3% Si-Fe during reheating from 1230·C to 1400·C. These large grains are undesirable because of the greater difficulty incurred in obtaining the suitably uniform and fine primary grain size desired prior to the final high temperature anneal during which the (1100)[001] texture is developed. It was found that the driving force for the growth is the subgrain structure which develops due to the strains of solidification and cooltng during continuous casting, however. the temperature at which growth initiates is related to the austenite-ferrite phase relationship. The grain growth begins when the austenite which forms during slab reheating decomposes to form highly perfect ferrite which then grows by consuming the strained preexisting (as-cast) ferrite matrix.

(2:30 p.m.) POTENTIAL OF SPENT CATALYSTS AS A SOURCE OF CKITICAL META\.S: R. E. Siemens, B.W. Jong, and J.H. Russell, Albany Research Center.-~of Mine's, U.S. Department of the Interior, Albany, OR. Under a Bureau of Mines contract to determine if spent catalysts represented a significant resource of critical metals, it was reported that about 27 million pounds of such metals as Co, Ni, V, W, Mo, Cr, Fe, Cu, and Zn are consumed annually by industrial catalyst users and that less than half of this amount is recovered and recycled. The Bureau initiated a research effort for recovering valuable metals from spent hydroprocessing, hydrogenation, and high-temperature shift catalysts. Characterization studies suggested that efficient extraction with conventional techniques would be difficult. However, 60 to 99 pct of the critical metals were extracted from spent hydroprocessing catalysts by anhydrous chlorination at 300 to 500 0 C or by ammoniacal sulfate, sulfuric acid, or caustic leaching. Sodium carbonate roastirig at 600 0 C, followed by water leaching, resulted in the extraction of 92 pct Cr from a spent high-temperature shift catalyst.

(2:55 p.m.) METAL RECOVERY FROM PERMANENT MAGNET ALLOY GRINDING SLUDGE: J. L. Holman and L. A. Neumeier, Rolla Research Center, Bureau of Mines, U.S. Department of the Interior, Rolla, MO. A technique was devised for treating Co-Ni bearing permanent magnet grinding sludges to remove contaminants and permit recovery

of an alloy powder believed sui table for recycling. Several magnet producers use elemental sulfur to hold magnets during grinding, resulting in sulfur and sulfate-sulfide contaminants in the sludge. Lubricating oil and grinding wheel binder produce carbon contamination. To render the sludge metallica recyclable, sulfur and carbon must be decreased to low levels since alloys, such as Alnico, have low tolerance for these elements. The patented technique, devised in bench-scale experiments, comprised: (1) treatment with organic solvent to remove a major portion of the elemental sulfur and oil; (2) drying, light grinding, and

TMS-AIME Annual Meeting Program - 59 magnetic separation to remove a major portion of the grinding media; (3) contr'olled oxidation-roasting to remove residual sulfur and carboni and (4) hydrogen reduction of metal oxides. The powder product contained about 0.01 pct S, 0.06 pet C, and 30 pct Al 2 0 3 • When adding the product to an experimental Alnico melt, the alumina floated to the slag.

SHEAR LOCALIZATION II Sponsored by the TMS Shaping and Forming Committee Tuesday, February 26, 1985 2:00 p.m.

Colonial Room Sheraton City Squire

Session Chairman: Lee Semiatin, Metalworking Section, Battelle's Columbus Laboratories, 505 King Ave., Columbus, OH 43201 (3:20 p.m.) Recovery of Copper from Secondary Copper B.F. Slags By V.L. Prabhu and R.G. Reddy Department of Chemical and Metallurgical Engineering" MaG:kay School of Mines, University of Nevada - Reno Reno, Nevada 89557 Industrial slags were treated by high temperative techniques for the recovery of copper' in alloy phase for the conditions of: 1. temperature, 2. carbon addition, 3. stirring the liquid bath, and 4. the CaO flux addition to the liquid bath. The results showed that copper recovery in alloy phase increased with increase in temperature, carbon addition, CaO flux addition and stirring of the liquid melt. The maximum copper recovery obtained was 85% at l350o C, 88% at 8% carbon addition, and "85% at 2% CaO flux addition. The results obtained have been compared with the recovery of copper from other industrial smelting slags and discussed.

(2:00 p.m.) ADIABATIC SHEAR DURING HIGH STRAIN RATE DEFORMATION * Harry C. Rogers, Department of Materials Engineering, Drexel University,

Philadelphia, PA

191Q4.

Deformation-induced thermal effects playa major role in strain localization during high strain rate deformation of metals. Such strain localization is generally in the form of bands of intense local shear. A brief general review of this phenomenon is given. The role it plays in metalcutting and high rate metal forming process will be emphasized. Band generation and band properties are discussed in terms of deformation conditions and material microstructure. The predicted influence of material variables such as rate of strain hardening, thermal softening rate, over-all strength level and strain-rate sensitivity are compared with the results of recent experiments. Som~ thoughts and observations on the interplay of dynamic ductile fracture with adiabatic shear straining will also be presented.

* Funding

for the author's own research in this area has been frotn the U. S. Army Research Office.

(3:45 p.m.) CHLOR1DE BASED DISSOLUTION OF lIARDFACE ALLOY GRINDING WASTE: L. D. Redden, S. M. Giroux, R. D. Groves, and D. C. Seidel, Salt Lake City Research Center, Bureau of Mines, u.S. Department of the Interior, Salt Lake City, UT. Dissolution studies were undertaken to develop a rapid method for digesting hard face alloy grinding waste. A laboratory method was devised which included solvent degreasing and dissolution in hot hydrochloric acid sparged with chlorine gas. Satisfactory dissolution was also achieved by leaching separately with hydrochloric acid or aqueous. chlorine; however, these two leaching systems produced liquors not amenable to subsequent processing due to a high tungsten concentration. Leaching with both hydrochloric acid and chlorine gas precipitated tungsten almost quantitatively, producing a suitable liquor for cobalt, nickel, and chromium recovery.

(2:30p.m.) STRAIN LOCALIZATION IN t'ETALS n~FOR"~D BY SHOCK LOADING.* Rohde, Sandi a National Laboratories, Livermore, CA.

~

Flyer plate techniques have been used to deform metals in well controlled uniaxial strilin shock compression conditions at strain rates of about 106 sec-I. These loading conditions caused various material s to deform by several mechanisms including inhomogeneous slip band formation, by twinning, by homogo:neous dislocation generation and motion, and phase transformatlon. The relationship between the unique shock loading conditions and deformation mechanisms will be discussed with emphasis on strain localization. *This work supported by U. S. Department of Energy. (3:00 p.m.)

(4:10 p.m.)

SHEAR- LOCALIZATION IN

DISSOLUTION OF NICKEL FROM A SUPERALLOY SCRAP BY A.C. S. V,nkat~halam and S. Malvi, Dept. of Met. Engg., t.t . . Bo ay - 400 076. Nickel and Platinum group metal. can be conveniently dissolved in acids by A.C. electrolysis. In this work, the electrochemical dissolution of nickel from a Ni base superalloy scrap by A.C. is reported. HCl was used as the electrolyte. The influence of current density, concentration of· HCl, frequency of A.C., and time of electrolysis on the dissolution of Ni was investigated. The current efficiency for Ni dissolution increased with increasing current density initially and subsequently decreased. Higher acid concentration increased the dissolution of Ni-. A decrease in the dissolution of Ni occurred with increasing frequency of A.C. and with the progress Of. electrolysis. Co dissolution was found to be negligible. ELECTROCHEMI~L

(4:35 p.m.) RECOVERY OF NICREL AND OTHER HETALS FROM NICREL ALj,OY SCRAP: Hi-jun Shiao, Mao-sen Lin, and Wei-jun Lan, Department of Nonferrous Metallurgy, Northeast UniverSity of Technology, Shenyang, Liaoning, China. A pilot-plant procedure treated alloy scrap containing 30-60%

Ni, 0.5-15% Cr, and 0.1% Co to recover nickel and other metals. Alloy scrap was melted in an electric furnace and cast into an anode plate for electrolysis in a chloride

electrolyte.

Effective electrolytic conditions were 200-250

amps per square meter, 60-65 0 C, a 4- to

-4.~

pH catholytic

solution containing 60-65 gIl nickel, and a 2- to -3 pH

~IACHINING:

R. Komanduri, General Electric

Corporate Research and Development, Schenectady, NY. Shear-localization occurs in high-speed machining of some of the difficult-to-machine materials [titanium alloys (0.-6 type),

nickel-base superalloys and hardened alloy steels (>300 BHN)]. The effect of crystal structure, hardness and thermo-mechanical properties of the work materials, and cutting speed on shearlocalization will be discussed. The mechanism of shear-localized chip formation will be presented.

(3:30 p.m.)

Break

(3:40 p.m.) ANALYSIS OF STRAIN LOCALIZATION IN A HIGH-ENERGY-RATE FORGING* T. C. Lowe, J. C. Lippold, J. C. Swearengen, Materials Department, Sandia National Laboratories, Li verroore, CA 94550 Manufacture of a high strength 304L stainless steel component by high-energy-rate forging of a cylindrical blank has been hindered by damage due to strain localization. Experiments were performed to study the effects of blank size, alloy composi tion, soak time, and forging temperature on the strain localization process. The forging process was also studied in a companion finite element analysis. Results show that blank size and forging temperature have significant effects upon the strain localization tendency. Larger blanks are more unstable due to greater constraint in the minor straining direction. Higher forging temperatures cause greater strain localization due to the variation ?f the work . hardening coefficient with temperature. Using thlS understandlng, it has been possible to suggest changes to the forging process which should avoid damage due to strain localization.

---------------------------------------------------------i~~~~-;~pported by U.S.D.O.E.

anolyte solution. Purified anolyte was prepared by removing

chromium hydroxide which was precipi tated by adding a Na2C03 solution at pH 4.2- to -4.6. Iron was eliminated with chlorine gas by vigorously aerating the solution to oxidize

the iron and precipitate ferric hydroxide at pH 4.8- to -5.0. Cobaltic hydroxide was also precipitated with the iron. Activated carbon and anion exchange resins were used to remove trace amounts of copper, chromium, zinc, and organic matter. After pH adjustment, the remaining purified solution was used for electrolysis in the cathode compartment where nickel was recove red.

(4:10p.m.) THE INFLUENCE OF MODE OF DEFORMATION ON STRAIN HARDENING OF IRON

AT LARGE STRAINS: A. Razavi, Dept. of Materials Engineering, Drexel University, Philadelphia, PA 19104; and G. Langford, Lehigh Testing Laboratories, 4029 New Castle Avenue, Wilmington, DE 19899 The strain hardening of interstitial-free iron was measured for plane strain elongation (strip drawing) up to natural strain of £=4. For comparison, the same material was also axisymmetrically

60 - TMS-AIME Annual Meeting Program elongated (wire drawn) to £=8. The two strain hardening rates are indistinguishable up to £;=;2, but the strain hardening of strip drawn material decreases thereafter, and becomes strongly negative at highest strain. New strain paths were applied to previously monotonically elongated wire to measure plastic properties of deformed wire in new sense of straining. Flow characterization of wire to strip strain path changes shows persistent work hardening rate after the orthogonal change in strain path deformation. The difference in work hardening of iron after monotonic elongation and strain path changes will be further discussed.

(3: 10 p.m.)

(4:40 p.m.)

SHEAR LOCAL! ZA TI ON I N ALUMINUM SHEET FORMING, R. Akeret, A1usuisse Research and Development, Neuhausen am Rheinfall, Switzerl and Failure in bending and stretch forming of aluminum alloy sheet is often connected with shear bands. The initiation and propagation of coarse sl ip steps appears to be controlled by the crystallographic orientation of the individual grains at the sheet surface, their size and misorientation at the grain boundaries. As coarse slip steps increase in length, the energy for their further propagation increases, so that harder obstacles can be overcome. Concurrently, the average orientation of a coarse slip step approaches the direction perpendicular to the major strain. If this direction coincides with the direction of mechanical fibering, ridging will develop at the sheet surface, resulting in lower formability. Fibering has usually been attributed to stringers of hard second phase particles. The present results show that textural and grain size segregation in stringers or in elongated colonies is 1a rge 1y respon sib 1e for the direct i ona 1 i ty of formi ng pro pert i es in aluminum sheet materials.

SURFACE ANALYTICAL TECHNIQUES FOR CORROSION STUDIES II: Aqueous Corrosion Sponsored by the TMS/MSn Corrosion and Environmental Effects Committee Tuesday, February 26, 1985 2:00

p.~.

t~me in both alloys. A lower oxidation rate was observed for the Inconel alloy 690 than for the Inconel 600. The elemental form of Ni was found near the solution-oxide interface for both alloys; whereas elemental Fe and Cr were not found until a significant amount of material was removed by sputtering. The microstructure of the corrosion film on Inconel 600 alloy, as found by scanning transmission electron microscopy, consisted of thick, loosely aggregated, accicular particles, whereas the film on the Inconel 690 alloy consisted of uniformly thin platelets.

Diplomat Sheraton Centre

Session Chairmen: S. M. Bruemmer, Battelle Pacific Northwest Laboratories, Richland, WA 99352; A. Joshi, Lockheed-Palo Alto Research Laboratory, Palo Alto, CA 94304

(2:00 p.m.) COMPOSITION AND STRUCTURE OF PASSIVE FILMS ON STAINLESS STEEL J. B. Lumsden, Rockwell International Science Center, Thousand

Oaks, CA 91360; D. A. Harrington and A. T. Hubbard, University of California, Santa Barbara, CA The structure and chemistry of films which form on the clean, annealed (Ill) surface of a Fe-17Cr-13Ni stainless steel single crystal have been analyzed using LEED, XPS and AES. Films were formed by exposing the surface to 02. water vapor and liquid water. All films formed at room temperature were amorphous. The composition analysis indicated a duplex film. The surface was composed of iron oxide following exposure to 02, and a hydrated iron oxide following exposure to water. The film adjacent to the surface was an oxide of chromium. Heating the crystal following or during exposure to gases produced an ordered film and a change in composition.

This work was supported by the National Science Foundation, Grant No. DflR-821352!.

(2:25 p.m.) EVIDENCE OBTAINED BY XPS OF A BI-POLAR FIXED CHARGE INDUCED MECHANISM OF PASSIVITY IN SIS: C.R. Clayton, A. Brooks, Y. Lu; Department of Materi a 1s Sci ence and Engi neeri ng, Stonybrook, NY. Variable angle XPS has been used to evaluate the inner and outer regions of the duplex passive films fonned on a series of Fe-Cr, Fe-Cr-Ni, Fe-Cr-Ni-Mo alloys in hydrochloric and sulfuric acid. Cr'+ has been observed ina 11 pass i ve films and is found to operate as a cation selective species. X-ray decomposition of Cr'+ species has been observed and will be discussed. (2:50 p.m.) COMPOSITION AND STRUCTURE OF THE CORROSION FILM ON Ni-Cr-Fe ALLOYS 600 AND 690 IN PWR·PRIMARY WATER: S. K. Hwang, Westing-

house R&D Center, pittsburgh, PA; G. P. Airey, C.E.G.B., Gloucester, England; and R. J. Jacko, Westinghouse R&D Center. The chemical and metallurgical characteristics of the corrosion film formed on_ two nickel-base alloys were studied after exposure's of up to 3000 hours in a simulated primary water environment of a pressurized water reactor at 360 Q C. Auger electron spectroscopy and X-ray photoelectron spectroscopy were used to demonstrate that the corrosion film was a multi-phase oxide which consisted of Cr203, Fe304 and NiO in the order of dominance. Additionally, considerable amounts of AI, Si and Mg were found near the oxidemetal interface. The oxide film thickness increased with exposure

ESCA STUDIES OF ZINC PHOSPHATE TREATED COLD ROLLED STEEL: S.P. Clough and J.S. HalllTlond, Perkin-Elmer, Physical Electronlcs Division, Eden Prairie, MN F.G. Katje, Whirlpool Corporation, Research and Engineering Center, Benton Harbor, MI. Zi nc phosphate is a commonly used surface pretreatment for painted applications of cold rolled steel used to inhibit corrosion and enhance paint adhesion on the metal surfaces. A systematic investigation using ESCA to characterize the surface chemistry of a zinc phosphate treated steel after selected processing steps has identified changes in surface chemistry at each s~ep. The removal of ionic contaminants, changes in hydration and the incorporation of a Cr containing skin have been quantitatively measured with ESCA. These changes have not been identified using bulk analysis techniques.

(3:30 p.m.) SCANNING AUGER MICROPROBE, ELECTRON STIMULATED DESORPTION AND X-RAY PHOTOELECTRON SPECTROSCOPY USED TO STUDY THE CORROSION OF CAST AL-CU-SI ALLOYS: J.A. Psioda, K.L. Guyer, H.F. Hillery,

Union Carbide Corp., Tarrytown, NY and L. Salvati, Perkin Elmer, Physical Electronics Div., Edison, NJ. Cast AI-Cu-Si alloys are being used increasingly to reduce the weight of automotive engine components. The as-cast microstructure is heterogeneous, however, and in aqueous environments localized corrosion can occur at discrete phases. To follow the corrosion process, techniques are required that combine surface sensitivity and high spatial resolution. Local attack during anodization was studied with high resolution SAM. ESD was used to probe for the low atomic number species which are often driven away by electron beams and missed by Auger alone. The desorbed materia.l is ionized by the electron beam and detected with a quadrapole mass analyzer attached to the SAM. Average composition and chemical state of the surface was determined by XPS. Techniques are demonstrated for two AI-Cu-Si alloys where a reduction iIi uniform anodization and an increase in local attack followed the addition of chlorides to the electrolyte.

(3: 50 p.m.) AES STUDY OF SURFACES PRODUCED BY SELECTIVE DISSOLUTION IN AL-CU ALLOYS:* D.Y. Jung and M. Metzger, University of Illinois at Urbana-Champalgn, Urbana, 1L. The evolution of surface structure in sulfuric acid was examined in depth profiles for single-phase alloys from 0.06% to 2.0% Cu and the results interpreted with the aid of concurrent TEM and electrochemical observations. At -0.5 V(SCE), an immune potential for copper, a dispersion of small copper particles on the substrate and an underfilm enrichment were present. At -0.1 V(SCE), there was a s i gni fi cant di sso 1 uti on current for copper; underfi 1m enrichment was still present but evidence of particles only in the 2.0% Cu alloy. The basi c enri chment step was taken to be the formation of a pure alumina film over the alloy; a copper signal from within the film in one alloy was attributed to trapped copper fragments not visible by TEM. Mechanisms of copper loss from the electrode were proposed. *Supported by the National Science Foundation through the Materia 1s Research Labora tory.

(4:10 p.m.) USE OF SURFACE BEHAVIOR DIAGRAMS TO DETERMINE HYDRATION INHIBITOR PROPERTIES FOR IMPROVED DURAB IL lTV OF ALUMI HUM ADHESIVE BONDS: G.D. Davis, J.S. Ahearn, and J.D. Venables, Martin Marietta Laboratones, Baltimore, Maryland 21227 Treatment of Al adherends with hydration inhibitors markedly improves durabil ity of adhesi ve bonds. Honethe 1ess, in wedge tests the crack propagates at the adhesive-adherend interface, indicating that improvements may be possible. Accordingly, we studi ed adsorption of inhi bi tors and hydration of treated surfaces using XPS surface behavior diagrams. Water initially present is displaced during adsorption by an inhibitor IOOnolayer. Hydration of these surfaces is limited by inhibitor dissolution. In wedgetests using the best inhibitor, the crack propagates at the interface prior to hydration. By contrast, failure in adherends not treated occurs as the oxide hydrates. We have identified cri teri a for i nhi bi tors des i gned to improve bond performance: displacement of water and occupation of all active sites, formation of strong inhibitor-surface bonds, insolubility of the inhibitor-Al complex in aqueous solutions, compatibility with the adhesive, and coupling to the adhesive.

TMS-AIME Annual Meeting Program - 61 (4:30 p.m.)

CORROSION BEHIIVIOR OF AMORPHOUS FILMS FABRICATED BY ION BEAM MIXING: R.S. Bhattacharya, A.K. Rai, J.R. Twist, P. P. Pronko; universa 1 Energy Sys terns, 4401 Day tonXeni a Road; Dayton, OH. Amorphous TiNi fi lms were fabricated by high (MeV) energy ion beam mixing of alternating thin films of Ti and Ni deposited on Ni substrates. The corrosion resistance of these layers were studied in 1 M nitric acid solution using potentiodynamic polarization technique. Results indicate a significantly improved corrosion behavior for the ion beam mixed TiNi films compared to the as-deposited films. The structure of the ion-beam-mixed TiNi films was observed to change from amorphous to polycrystal ine during anneal ing studies as the anneal ing temperature was increased. The thickness and composition of the passive oxide layer which formed by anodic polarization on the ion beam mixed TiNi films was examined using Ion Scatteri ng Spectroscopy (I SS) and Auger El ectron Spectroscopy (liES).

WEDNESDAY AM ALUMINA & BAUXITE - IV: Instrumentation and Control Sponsored by TMS Light Metals Committee Wednesday, February 27, 1985 8:30 a.m.

Royal Ballroom B Sheraton Centre

Session Chairmen: Dan Macfie, British Alcan Aluminium Ltd., Burntisland, Fife, Scotland; W. L. Love, Aluminum Company of America, Alcoa Technical Center, Alcoa Center, PA 15069

(8:30 a.m.)

ACCURATE ANALYSIS OF BAUXITE SAMPLES BY AN XRF FUSION f1ETHOD, F. East, Al can International Limited, Kingston Laboratories, Ki ngs ton, Ontari o. Calcined bauxite samples are fused at 10000C with 90% Li?Ba07/ 10% LiF in the proportions 1 to 6. The molten mixtures are cast as homogeneous and transparent glass disks which can be submitted directly to X-ray fluorescence (XRF) analysis. Up to 6 samples can be prepared at the same time with a Claisse fluxer, for a total preparation time of about 5 minutes per sample. Advantages of the fused disk over the powder briquette method are as follows: Increased accuracy and large reduction in matrix effects. 1) Universality, since mineralogical differences between 2) deposits are el iminated. Standard.ization with synthetic reference samples made of 3) pure compounds. (9:00 a.m.) ANALYTICAL INSTRUMENTATION FOR AVAILABLE ALUMINA AND SOLUBLE SODA ANALYSES: Charles K. Matocha, Alcoa Technical Center, Alcoa Center, PA 15069

Available Alumina - Instrumentation has been developed to automatically control the reaction temperature for the IOO-mL caustic digest of bauxite for determination of available alumina. Thermocouple feedback from the two digest vessels controls gas heaters which maintains the sought reaction temperature. The lOO-mL reaction vessels used with this instrument have been commerically established. Soluble Soda - Soluble soda content of wet hydrate can be monitored in a production environment by measuring the conductivity of a leached sample. The Alumina Soluble Soda Analyzer - ASSA - is used off-line for this determination. The successful application of this instrument along with salllpling procedures and correlation of conductivity to the laboratory determination are discussed.

(9:30 a.m.)

USE OF CONDUCTIVITY TECHNIQUES TO FOLLOW Alz03 EXTRACTION AT SHORT DIGESTION TIMES, G.D. Fulford, Al can Internati onal Limited, Kingston Laboratories, Klngston, Ontario. A connnercially available electrodeless electrical conductivity probe has been calibrated to give an empirical relationship: conductivity = f (caustic concentration, alumina/caustic ratio, causticity, temperature, solids concentration) over a wide range

of the variables. If the initial caustic concentration, causticity and solids concentration in a digest are known, simultaneous 'measurement of temperature and conductivity (at time intervals of as little as 0.25 s) permits ratio to be determined while a normal gibbsite digest is in progress. Some preliminary laboratory applications to the study of the extraction of alumina at very short times are presented. (10:00 a.m.)

Break

(10:30 a.m.) AUTOMATION MEASUREMENT OF MUD INTERFACE LEVEL:

V. N. Parikh,

C. E. Phillips, Kaiser Aluminum and Chemical Corp., Gramercy,La. A simple and reI iable sensor probe has been developed to automatically measure mud-liquor interface level in Bayer plant mud thickeners. Mud-liquor interface level is an important factor in mud thickener process control used to determine flocculant dosage and underflow pumping rates. A siphon action passes the process I iquor through a sensor probe consisting of a glass tube, lamp and photodiode. The photodiode voltage varies with the absorption of 1 ight by the process I iquor. The presence of mud in the 1 iquor greatly increases the amount of 1 ight absorbed. The level of the sample point at the time of the photodiode voltage change is equal to the interface level. Monitoring of the sensor operation and operator interface are done by a Fox 3 computer. The process I iquor is not in di rect contact wi th the sensor probe resulting in longer life compared to the instruments presently available in the industry. The automatic measurement of interface level allows closer process monitoring while decreasing the required amount of manpower.

(11 :00 a.m.) MODERN CONTROL INSTRUMENTATION AND PROCESS MANAGEMENT IN BAYER PLANTS

P. McIntosh, Technical Manager, Queensland Alumina Limited E. L. Barker, Chief Instrument Development Engineer, Kaiser Aluminum & Chemical Corporation. Oakland, Ca. Successful implementation of modern microprocessor based control instrumentation and computer based process management systems offers the potential for large raw material and energy cost savings in Bayer plants. These benefits cannot only be gained in new plants but also from modernization of existing plants. This paper reviews the hierarchial control available with modern systems. The management, hardware selection, system design, maintenance and support requirements for successful implementation are covered.

(11 :30 a.m.) USE OF MICROPUTER FOR DIRECT DIGITAL CONTROL AND OPERATOR INTERFACE: W. H. Jeffcoat and R. E. Fleming, Kaiser Aluminum

and Chemical Corporation, Gramercy. louisiana The successful use of low cost microcomputers for realtime process control can be cost effective if the I imitations of the computer are understood. The application discussed here is a ten loop batch process which uti I ized the microcomputer for operator interface and direct digital control of the chemical process. Key points leading to the success of the project are: a)

CRT based control system was needed to give control room operator step-by-step instruct ions.

b)

The microcomputer and associated 1/0 was cost effective when compared to panel mounted controllers.

c)

Microcomputer operating syster,l allowed for multitasking. However, the ope rat i ng sys tem does not have an on-1 i ne ed i tor

d)

The number of loops (ten) made it impossible for large

manufacturers of CRT based digital control systems to compete due to price.

62 - TMS-AIME Annual Meeting Program ALUMINUM REDUCTION TECHNOLOGY IV: Modeling and Analysis . . . Part B Sponsored by TMS Light Metals Committee Tuesday, February 26, 1985 2:30 p.m.

Royal Ballroom A Sheraton Centre

Session Chairmen: R. D. Zabreznik, Kaiser Aluminum & Chemical Corp.,

P.O. Box 1600, Chalmette, LA 70044; D. M. Macmillan, Alcan Interna· tional Ltd., C.P. 1250, Jonquiere, Quebec G7S 4L2 (8:30 a.m.) EFFECT OF OPERATING CONDITIONS ON THE DISSOLUTION OF PRIMARY AND SECONDARY (REACTED) ALUMINA POWDERS IN ELECTROLYTES: A. N. Bagshaw/G. Kuschel, M. P. Taylor, S. B. Tricklebank and B. J. Welch, Dept. of Chemical and Materials Engineering,--rne University of Auckland, Auckland, New Zealand. This paper focuses attention on the dissolution characteristics of various alumina powders in 1 ithium modified and conventional electrolytes. The study encompassed a range of primary and secondary (reacted) aluminas as well as some laboratory prepared specimens. The range enabled independent assessment of the importance of alpha content and L.O.1. Results for additions to baths with 1 imited superheat were consistent with earlier findings that indicated heat transfer played an important role under those conditions. Aluminas with a higher transition content (e.g. low alpha) dissolved faster. A more dramatic increase in dissolution rate is achieved by using aluminas which release volatiles in the bath. These are consistent with heat trans fer control a lthough mass trans fer contro 1 is not precluded. There is nothing to suggest the dissolution of alumina is retarded in lithium baths.

(9:00 a.m.) SULPHUR CONTAINING COMPOUNDS IN THE ANODE GAS FROM ALUMINUM CELLS, A LABORATORY INVESTIGATION. R. Oedegard, S. Roenning, A. Sterten, and J. Thonstad Laboratorles of Electrochemistry and SINTEF, The Foundation of Scienti fie and Industrial Research at The Norwegian Institute of Technology, Trondheim, Norway

(985 0 C)

Anode gas from a laboratory electrolysis cell was sampled without any contact with oxygen and analyzed by gas chromatography. Prebaked anodes with 1-2 wt~o sulphur were used. Apart from CO 2 and CO the following gas species were found: CS 2 , H2 S, COS and S02' For CO /CO ratIOS that are normal for aluminum celrs (4-5) the major sutphurous compound was COS. The total sulphur content in the anode gas was high at the beginning of electrolysis with a new anode, and it decreased gradually during 2-3 hours reaching a steady state in accordance wi th the mass balance. Thermodynamic calculations for the equilibria between CO 2/CO and the various sulphurous gas species will be presented and compared wi th the experimental resuI ts.

(9:30 a.m.) INFLUENCE OF BATH DENSITY IN ALUMINIUM ELECTROLYSIS Halvor Kvande and Helge R¢rvik, Ardal og Sunndal Verk a.s., N-5875 Ardalstangen, Norway. The bath d€nsity is an important physico-chemical parameter in aluminium electrolysis. In order to prevent mixing and achieve good separation, the density difference between bath and m~3al preferably should be larger than about 0.20 9 cm . The bath density also affects the solution of alumina. The present paper reviews literature data for the density of various cryolite melts. A theoretical equation has been developed for calculation of the density as a function of bath temperature and composition. The results and the practical application of this equation are discussed. (10:00 a.m.)

Break

(10:30 a.m.) CURRENT EFFICIENCIES -- RELATING FUNDAMENTAL STUDIES TO PRACTICE: Grjotheim, Institute of Chemistry, University of Oslo. Norway; W. E. Haupin, Alcoa Laboratories, Alcoa Center, Pennsylvania 15069; B. J. Welch, Department of Chemical and Materials Engineering, Unwerslty of Auckland, Auckland, New Zealand Better understandi ng of bath chemi stry and mathemat i ca 1 mode 1i ng of magnetic fieldS, fluid flow and current efficiency has lead to modern cell s havi ng current effi ciencies greater than 95%. Precise evaluation of the various models has been hindered by the difficulty of maintaining control in operating cells for a sufficient time to substantiate the predicted performance. In this review, these models are critically compared and examined for their implication on applying the knowledge to older cells and determining what the maximum possible current efficiency is likely to be in the future. For the latter, attention will need to be focused on other secondary reactions previously considered to be unimportant. ~.

(11 :00 a.m.) ON ALUMINA PHASE TRANSFORMATION AND CRUST FORMATION IN ALUMINUM CELLS R. Oedegard, S. Roenning, S.Rolseth, and J. Thonstad, Laboratories of Electrochemistry and SINTEF, The Foundation of

Scientific and Industrial Research at The Norwegian Institute ofT echnology, Trondheim, Norway The catalytic effect of fluorides on theY~ t:l.-AI 20 phase transformation was studied by keeping alumina samp1.es with addition of different fluorides (2wU~) for 30 minutes at various temperatures. After heat treatment the Ct-AI 20 3 content was analyzed by means of X-ray diffraction. The phase transformation occured within a narrow temperature range ( 50 0 ) and the characteristic temperatures increased in the order AlF 3 (800 0 C), cryolite (880), NaF(935), CaF 2 (980), no additive (1040), NaOH( 1115). Aluminum hydrate snowed higher transformation temperatures than alumina. Dry scrubber alumina was transformed at about 785 0 C. During phase transformation an alumina network is formed wich reinforces the crust on top of cryolite bath. Such strengthening was not observed when the initial content of a -A179o was above 5m~ or when the temperature was be low BBlJ C..

(11:30 a.m.) A NEW

TREATMENT

FOR

VOLTAGE

INSTABILITY

IN

HORIZONTAL

STUD

CELLS: A. C. Brant Filho, presented by P. Venugopalan, Alcan Aluiminio do Brasil Nordeste S.A., Aratu Works, Caixa Postal 30.553, 01000 Sao Paulo, SP, Brazil

In horizontal stud Soderberg cells J the effective area of the anode is less than the projected plan area because of discontinuities of the anode face due to the void volume which occurs as a result of pulling of contact studs. This causes an effective variation of about 10% in anode current density through a stud pulling cycle. A method has been developed to modify the computer process control logiC to allow for this variation, based on the monitoring of the noise level of the voltage signaL

CARBON TECHNOLOGY IV Sponsored by the TMS Light Metals Committee Wednesday, February 27, 1985 8:30 a.m.

Georgian Ballroom Sheraton Centl

Session Chairmen: P. G. Campbell, Alumax of South Carolina, P.O. B.

1000, Goose Creek, SC 29445; B. J. Racnas, Aluminum Company America, Alcoa Laboratories, Alcoa Center, PA 15069 (8:30 a.m.) DEVEIDFMENr OF AN OPI'IMlZED RCa.! TEMPERATURE CATIUlE RAMMING

PASI'E: W. R. Hale, Kaiser Aluminun & Chanical Corporation, Tacoma, Washington 98421, and 1. Sobolev and E. Panusch, Kaiser Aluminum & Chanical Corporation, Pleasanton, California 94566. During recent years, aluninun producers have shoNn increasing interest in cathode ramning pastes that can be applied at ambient tenperatures. Such pastes offer installation flexibility, econanical hahdling, and less fume emissions than conventional hot pastes. To meet this interest, Kaiser Aluminum & Chanical Corporation has developed an optimized roan temperature cath:Jde ranming paste. Based on modifications of the c~nents used in hot pastes of proven perfonnance, the paste offers high baked density; low fune emissions, convenient ambient temperature application, and gcod storage stability. Plant perfonnance to date has been excellent.

(9:00 a.m.)

POTLn:ING FAILURE MODES: ti. Benial!lin!&l.J.. Consultant 144 Woodshire Dr., Pittsburgh, Pa. 15215 In aluminum s~elting cells inprovements in pot1ining life,must deal with specific modes of failure observed in a particular potline. To aid in decisions on making changes in design, materials or operation the types of failure must be identified. Types of failure may be classified by their location: in the bottom lining, Sidelining, shell and collector straps. Each failure mode is described along with the causes and sugeested remedies. (9:30 a.m.) AN INVESTIGATION OF INTERACTION OF THE ALKALI AND ALKALI-EARTH METALS WITH THE CARBON-GRAPHITE METERIALS: N. A. Kaluzhsky,

V. Ya. N'ikitin, VAMI Institute, Stredmye Prospect 86, 199026, Leningrad, USSR. Methods and results of investigation of action of alkali and alkali-earth metals with various carbon materials used for pot lining are given. The study showed that alkali earth metals penetrate into inter layer space of carbon materials. This penetration may occur at certain temperatures both from molten metal and its vapours. Interaction of alkali earth metal is followed by the same temperature regularity as that of alkali metals. Carbon and graphite materials adsorb fewer atoms and molecules at higher temperatures and upon reheating to high temperatures adsorbed alkal i earth metals are driven out. Major features of action of alkali earth metals as compared with alkali metals with carbon and graphite meterials are shown.

(10:00 a.m.) QUALITY INSPECTION PROCEDURES FOR PREBAKE CATHODE BLOCKS: Tu-Lung

Weng, Kaiser Aluminum & Chemical Corporation, Pleasanton, CA This paper describes quality inspection procedures developed at Kaiser Aluminum & Chemical Corporation reduction plants. These

TMS·AIME Annual Meeting Program· 63 procedures are used to examine prebake cathode blocks supplied by new manufacturers, fabricated with different materials, and/or made by modified processes. The inspection procedures employ ultrasonic velocity and electrical resistance measurements, and are performed in two sequential steps: First, a thorough examination of a limited number of blocks to diagnose any problem areas that may exist and, second. a simplified, directed test aimed at quickly inspecting the rest of the blocks. A study of blocks supplied by two vendors is presented. In the first instance, the initial diagnostic work shows the blocks to be acceptable and, hence, no further inspection is "necessary. In the second instance, the ends of the blocks exhibit high electrical resistances--due to underbaking. Here, selective electrical resistance measurements are made on all the remaining blocks to determine their acceptability.

(10:30 a.m.) EVOLUTION OF THE CATHODIC OHMIC DROP DURING THE ELECTROLYSIS IN THE ALUMINIUM CELL: Ch. Michel, Rand D, Societe des Electrodes et Refractaires Savoie, 69631 Venissieux, France. The cathodic ohmic drop of an aluminium cell is not correlated to the cold electrical resistivity of the carbon blocks before use. The evolution of the electrical resistivity has been followed in a test cell at 975°C as a function of the time. The anisotropy of the materials has been taken into account. This evolution is correlated to the sodium penetration but this phenomenum is different from and faster than the well known graphitisation at low temperature. When the electrical resistivity is stabil i zed, the di fference between carbons conta i ni ng 1ess than 40 % of graphi te is very sma 11. The mai n factors whi ch determi ne the cathodic ohmic drop are the speed of the sodium penetration (mos tly duri ng the fi rst months of operati on) and the qual i ty of the contact between the collector bar and the carbon. Parameters which determine the speed of the sodium penetration and the quality of the contact are discussed. (11 :00 a.m.) THE EFFECTS OF PITCH AND FORMULATION VARIABLES ON PROPERTIES OF RAMMING PASTE FOR PREBAKE CATHODES: D. Jurie, Comaleo Aluminium (Bell Bay) limited, Bell Bay, Tasmania, 7252, Australi.a.

The failure mechanisms of both the monolithic and prebaked reduction cells were found to be related to the shrinkage tendency of the ramming paste during baking. Monolithic pots developed extensive bakeout cracks which led to accelerated failure rates while prebaked pots tended to have excessive bath leaks between the block ends and the perimeter pack. This also led to premature failures. The shrinkage tendency of ramming paste was found to be influenced by the formulation variables such as granulometry, pitching level and temperature of mixing, but particulary the composition of binder pitch. Highest shrinkage during baking, highest sodium disruption, and the lowest potlives were obtained with pitches having less than 15 percent beta resin. Optimization of formulation variables and beta - resin content of pitch led to reduction of shrinkage tendency and an irqprovement of potlives.

(11:30 a.m.) HOW TO IMPROVE THE PIG IRON SEALING OF COLLECTOR BARS IN CATHODE MATERIALS Italo Letizia, Elettro Carbonium S.P.A. ~ Narni, Italy

The investigation shows the decreasing of the contact voltage drop when preheating of cathode carbon block and metallic bar is carried out at suitable temperatures and in conditions which do not alter the original structure of the cathode carbon block. The wing cracks (WC) in the cathode carbon block can be avoided by modifying the slot geometry and decreasing the casting temperature of pig iron. The corner cracks (CC) are reduced if thermal gradients in the cathode carbon block during the preheating and the cooling processes are kept within ve"ry narrow range.

CAST SHOP TECHNOLOGY I Sponsored by the Light Metals Committee Wednesday, February 27, 1985 8:30 a.m.

Georgian Ballroom B Sheraton Centre

Session Chairmen: Paul Breneke, Coors Container Co., 17755 W. 32nd Ave., Golden, CO 80401 and Clark Weaver, Alcan Smelters & Chemicals Limited, P.O. Box 1500, Jonquiere, Quebec, Canada G7S 4L2 (8:30 a.m.) AN IMPROVED SYSTEM FOR SCRAP MELTING IN REVERBERATORY FURNACES, David V. Neff, Metaullics Systems, Solon, Ohio. A new scrap melting systems SAMS (patent applied for) has been developed which provides for continuous melting, high capacity, is flexible and insensitive to scrap variation, and is highly efficient in terms of melt rate and metal recovery with minimal dross generation. The system is designed to be used in conjunction with a molten metal circulation pump. Operating parameters predicted by a water model simulator produced strong correllative results in actual melting furnace operations in Europe and in the U.S. Consistently high melting rates have been achieved and were limited only by available heat input into the furnace. Excellent metal recoveries have been obtained with a variety of scrap materials including UBC, painted siding, oily turnings, non-

de1acquered shredded scrap, and dross and skimmings. The total system is available under license and offers the user significant cost savings in furnace operations. (9:00 a.m.) MAGNESIUM REMOVAL FROM M1!LTKD SCRAP ALUMINUM, F. DIMAYUGA, J. HERBERTSON and R. HARRIS, DEPT. MINING & METALLURGICAL ENG., McGILL UNIVERSITY, Montreal, Canada H3A 2A7

Aluminum recycling has the problem of contamination by Mg. Zn. Fe Si and others. Mg is the only impurity removed (via chlorination). Vacuum refining offers an alternative method of 'demagging' and has the advantage of all volatile being removed. Experiments were performed in a 3m 3 , 150kW VIM on 10-12 kg melts starting with 2-5% Mg. Zn, Pb and SN. Rates of removal were found to be around lxlO- 5 m/s for Mg and Zn, and 5x10- 7 for Pb. Compared to theoretical rates (on the basis of melt diffusion and evaporation), the observed rates were at least an order of magnitude smaller and attributed to a slag/oxide/dross formed of the impurity species on the melt surface. A technique to avoid this has been developed in which liquid aluminum is lifted from the bulk of the melt and sprayed into the vacuum by the action of injected gas rising through a vertical tube placed in the melt. Preliminary findings for this 'LIFT-SPRAY' process indicate an increase in refining rates by a factor of 2 to 20.

(9:30 a.m.) PRACTICAL AND TECHNICAL CONSIDERATIONS FOR SELECTION OF GRAIN REFINING ALLOYS IN THE CAST HOUSE: S.R. Thist1ethwaite and D. Hadlet, Anglo Blackwells Ltd., Widnes, UK, and J.C. Hoff, Samincorp, Division of Columbian Enterprises, Inc., New York, NY. A range of Al Ti and A1 Ti B master alloys are available for gra i n refi ni ng a 1umi nium. There is an i ncreas i ng tendency to use specifi c compos i ti on gra i n refi ners for different app 1 i cations. For example, lower boron levels to reduce TiB2 concentrations in thin sheet/foil, lower titanium to reduce Ti levels in recycled scrap and higher overall concentrations to reduce grain refining addition rates. A series of grain refining alloys (A1 Ti5 Bl, 5/.6, 5/.2, 3/1, 10/.4, A1 Ti6 and A1 TilO.) have been used to treat pure aluminium and 3004 alloy both in primary and recycled material with the correspondi ng di fferent base 1eve1 s of Ti and B. The results are evaluated in terms of grain refining effectiveness and potenti a 1 metal c1 ean 1 iness and on the bas is of these resu lts suggestions are made to assist in the selection of suitable grain refiners for the cast house. (10:00 a.m.) ALUMINIUM CLEANLINESS MONrTORfNG: METHODS AND APPLICATIONS IN PROCESS DEVELOPMENT AND QUALITY CONTROL. D. Doutre, B. Gariepy, J.P. Martin, G. Dube, A1can International Limited, Arvida, (Jonquiere), Qu€bec, Canada. G7S 4K8. The control of metal cleanliness is an essential part of the production of critical alloys. The measurement of metal cleanliness is complicated by the nonuniformity of the distribution of nonmetallic inclusions and by the extremely low concentrations encountered in most wrought aluminium alloys. This report describes the methods currently used by A1can companies for the measurement and control of metal c1 ean 1 i ness. Examp1 es of the effect of various melt treatment practices on metal cleanliness are gi ven. Recent advances in the deve 10Jl11ent of rapid, i n-l i ne methods of c1ean1 iness assessment are reviewed. (10:30 a.m.) PROBES FOR THE CONTINUOUS MONITORING OF SODIUM AND LITHIUM IN MOLTEN ALUMINUM:

A. A. Dubreuil and A. D. Pelton, Ecole Poly technique de Montreal, C.P. 6097, succursale "A", Montreal, Quebec H3C 3A7, Canada Solid electrolyte probes, based upon beta-alumina, have been developed which permit the continuous monitoring of the Na content of molten Al in the range 1 ppm to 100 ppm and of the Li content of molten Al in the range 1 ppm to 3 weight % with a precision and reproducibility sufficient for practical industrial applications. The probes are robust and thermal-shack-resistant and may be left in the Al bath for several hours.

DEFORMATION PROCESSING TMS-AIME General Abstract Session Wednesday, February 27, 1985 8:30 a.m.

Colonial Room Sheraton City Squire

Session Chairman: D. L. Bourell, Department of Mechanical Engineering! Center for Materials Science and Engineering, The University of Texas, Austin, TX 78712 (8:30 a.m.) EFFECT OF ACCELERATED COOLING ON THE MICROSTRUCTURE OF Nb-V MICROALLOYED STEELS, L.E. Collins and G. Crawford, Energy, Mines and Resources, CANMET/PMRL, Ottawa, Ontario, Canada

A study to determine the potential of accelerated cooling for the structural refinement of Nb-V microalloyed steels has been completed. Steels of composition O.llC-1.45Mn-0.05Nb andO-O.llV were deformed and cooled at rates from 0.1 to· 30 C/ s in a quenchdeformation dilatometer. The microstructures of the steels

64 - TMS-AIME Annual Meeting Program were studied by optical and transmission electron microscopy, and hardness tests were performed. Hardness increased with cooling rate due to the finer ferrite grain size, increased bainite content and refinement of the precipitate distribution. The V-bearing stee]s had higher hardness than the steel containing only Nb as the microalloying addi cion owing to the increased precipi tation of (Nb, V) (C,N). The magnitude of the hardness increase with cooling rate was greater in the V-bearing steels. It was also found that the period of time between the finish deformation and the onset of transformation was important in determining the degree of precipitation strengthening.

(8:50 a.m.) STRUCTURE AND PROPERTIES OF AS HOT ROLLED HIGH CHROMIUM MARTENSJTIC STEEL. R. Ramesh and G. Thomas, MMRD, Lawrence Berkeley Laboratory, Berkeley, CA 94720; N. J. Kim, Dept. of Mech. Engrg., University of Wyoming, Laramie, Wyoming 82701. The structure and properties of as-hat-rolled Fe/10Cr/.2C/lMn were compared with those of quenched and tempered steel. The main processing variables were deformation temperature, cooling rate after hot rolling and tempering temperature. An improvement in the impact toughness was achieved in the as-hat-ral1ed steel over the quenched and tempered steel without any significant concomitant loss in strength. The microstructure basically consists of lath martensite with interlath films of retained austenite and intralath 8utotempered carbides. In all cases massive laths were observed occasionally along the prior austenite grain boundaries. Details of the microstructure and its correlation to the mechanical properties will be discussed. This work is supported by the Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy under Contract No. DE-AC03-76SF00098.

(9: 10 a.m.)

ROLL PRESSURE MODELING OF MULTIPASS WARM ROLLING OF CARBON STEEL: E. V. Subraman i an and D. L. Boure 11, Department of Mechanica 1 Engi neeri ng/Center for Materi a 1s Science and Engineering' The University of Texas, Austin, TX 78712 Ferrous warm rolling is considered to be a potentially valuable manufacturing process. However, no systematic approach has been undertaken to assess intrins i c manufacturabil ity as indicated by such parameters as roll separating force and energy or power consumption. The purpose of this investigation is to characterize experimentally the effect of various process variables on the separating pressure. AISI-SAE 1015 and 1059 steel billets were warm rolled at temperatures ranging between 300°C and 700°C with various thickness reductions per pass up to a short transverse strain of about -1 at a strain rate of 10 s-l. Two approaches were used to model in predictive fashion the influence of important warm rolling variables on the separating pressure: an empirical approach and a second approach which utilized a semi-empirical warm working flow stress equation along with the theoretical slab method. Good agreement was found between the experimental and the predicted roll pressures. Sponsored by NSF DMR8113087. (9: 30

a.m.)

HOT DEFORMATION CIIARACTERISTICS OF A DUPLEX STAINLESS STEEL, S. K. Sriv.. tava and V. R. Iahwar, Cabot Corporation, Kokomo, IN

Tna hot deformation characteriitici of an Fe-Cr-Ni-Ho-N ba ..d duplex Itainll .. Itaal were .tud1ld by mean. of comprlliion teate. Flow curv.. of the material were obtained at four tilt temperaturll (950', 1000', 1050', and 1l00'C) at coutant .train rat •• from 0.005 to 5 IIc- l • The .p.c1men. ware rapidly cooled in water after deformation. For the ranae of deformation condition. Itud1ed, dynamic recry.tall1zation appaara to be the predominant loftenina mechanhm, thouah the m1cro.tructure condstl of austenite in e ferdte matrix. The flow behavior WAI analyzed in accordance with Sellara and Tegart'. correlation. The activation anergy of deformation (between 0.05 and 5 sec- l ) waa determined to ba 267.5 ;:30.5 KJ-mol- l • Detaned characterization of tha microstructure wal carded out for specimen. deformed at 1050'C .s a function of atrain and strain rate (0.05 and 5 sec- l ) by optical and electron microscopy.

(9:50 a.m.) EVALUATION AND COMPARISON OF WORKABILITY CRITERIA FOR TWO LIMITED-WORKA8ILITY STEELS:* Thomas A. Kircher and Roger N. Wright, Rensselaer Polytechnic Institute, Troy, New York. Workability criteria give a measure of resistance to fracture duri ng deformat i on process i ng. I n this study, roll i ng, upsetting, and tensile testing are done on 440 stainless steel and M42 tool steel. The fracture criterion as proposed by Cockroft and Latham is determi ned from tens il e da ta, and a fracture criterion for cold forming as proposed by Kuhn, Lee, and Erturk is determined from rolling and upset data. The two are compared in an analysis which assumes proportional loading and exponential strain-hardening. Further application of these criteria towards the cold-drawing of these steels is presented, with emphasis on the drawing of hexagonal bar from round stock. *This work supported by the RPI Center for Manufacturing Productivity and Technology Transfer.

(10:10 a.m.) AN INVESTIGATION OF TURBINE DISC FORGINGS PRODUCED FROM FINE GRAINED CASTINGS: L.J .Fiedler and D. G. Rosenthal. AVCO Lycoming Division, Stratford, CT. Fine-grain casting techniques are being developed which offer promising alternative approaches to the fabrication of super~ alloy turbine discs. This paper will describe the preliminary results of an evaluation of forgings produced from Vacuum Arc

Double Electrode Remelt (VADER)TM processed modified IN-IOO alloy. These studies have sho'WIl that the forgeability and properties of VADER-cast material are improved by a pre forging extrusion step. The mechanical properties of hot-die and isothermal forgings from VADER billet are compared with other conventional and powder metallurgy disc alloy forgings.

(10:30 a.m.)

Effect of Thermomechanical Processing Variables on Superplasticity in AI-IO.2Mg -0.5Mn. T.R. McNelley and E.W. Lee. Dept. of Mechanical Engineering, Naval Postgraduate School, Monterey, CA 93943. Warm rolling at 300 0 C of an Al-10.2Mg - 0.5%Mn alloy results in a refined substructure in conjunction with fine particles of B(Al S Mg 5 ) and MnA1 6 . This structure is superplastic at temperatures as low as 300 0 C and at relatively high strain rates (-10- 3 S-l). Under such conditions,little cavitation is observed. At higher test temperatures, high elongations are observed but more extensive cavitation is also seen. Various post rolling heat treatments have been investigated. Annealing below the roll -ing temperature is observed to enhance superplasticity at warm temperatures (300 0 ). Recrystallization by annealing at temperatures above the solvus for Mg (e.g. 440 0 C) results in supression of superplasticity at warm temperatures. (10:50 a.m.) GRAIN MORPHOLOGY EFFECTS ON SUPERPLASTICITY IN AL ALLOYS: M. W. Mhhoney and A. K. Ghosh, Rockwell International Science Center, T ousand Oaks, CA 91360 It has long been recognized that initial grain size is of primary importance when creating a microstructure suitable for superplastic extension. However, beyond grain size there are a number of other considerations with regard to grain morphology which are also of concern to superplasticity. For example, grain size stability, grain size distribution and grain aspect ratio each influence material superplastic properties such as flow stress behavior, cavitation and total elongation. These issues will be addressed for a1umi num alloys processed to a variety of grain sizes, shapes and distributions. It will be shown that cavitation preferentially nucleates at large grains and at grains with high aspect ratios. Accordingly, grain size distribution, in addition to grain size, is of primary concern for superplasticity. Also, a bimodal grain size can result in more rapid grain growth and thus cause an increase in flow stress with a corresponding increase in cavitation and reduction in superpl ast ic i ty.

(11 :10 a.m.)

SUPERPLASTICITY IN AL-Li ALLOYS: A. K. Ghosh and C. Gandh1, Rockwell International Science Center, 1049 Camino Dos R10s, Thousand Oaks, CA 91360 Low density Al-Li alloys are fut emerg1ng in the aerospace materials arena as the next generation alloys, Considerable 1nterest now ex1sts in exam1ning the grain refinement and superplastic forming potential of these alloys. Studies on the superplasticity of Al-L i alloys have demonstrated that an 1nitial fi ne gra in m1 crostructure 1n a thermomechani ca 11 y processed and recrystallized material tends to exhibit stra1n-assisted grain growth and cav1tation, and not a very high degree of superplastic elongation. On the other hand, aged and rolled m1crostructure can continuously recrystallize to a very fine grain size during the early part of superplastic stra1ning. Continued deformation leads to superplastic flow 1n the structure so produced and leads to much larger extent of superplastic elongat1ons. The changes in the sub-grain and grain structures during the two stages of flow have been characterized by optical and transmission electron microscopy. The flow stress determined at various constant strain rates are correlated with this microstructural information.

TMS-AIME Annual Meeting Program - 65 ENERGY REDUCTION TECHNIQUES IN METAL ELECTROCHEMICAL PROCESSES V Sponsored by TMS-AIME Electrolytic Processes Committee Wednesday, February 27, 1985 8:30 a.m.

Versailles Ballroom Sheraton Centre

Session Chairmen: Rolf Wesely, Anaconda, P.O. Box 27007, Tucson, AZ 85726; Krishna Y. Rao, Dept. of Metallurgical Engineering, Univ. of Washington, Seattle, WA 98195 (8:30 a.m.) THE CHALLENGE AND REWARDS OF COGENERATION APPLICATIONS:

(11 :00 a.m.) ENERGY CONSERVATION IN THE TANKHOUSE AT ASARCO'S AMARILLO COPPER REFINERY: W. J. Borzick, H. E. Tallert, P. E. Mettham, ASARCO Incorporated, P.O. Box 30200, Amarillo, TX 79120 USA. The original design of the ACR was engineered to optimize energy conservation. During nine years of operation, numerous additional measures have been taken to further reduce energy consumption. The improvements resulted from continuous efforts to incorporate state-of-the-art technology and a dedication to make efficient use of available energy. A significant contribution to this effort was the ABarca-developed reagent control technolo,gy for tankhouse electrolyte. This paper will describe how the original design ~and the subsequent developments impacted the energy conservation program at the

ACR.

Neville W. Morley, Amax Incorporated, 1707 Cole Boulevard,

Golden, CO

80401.

The author discusses the concept of cost and energy savings to be realized in the electrolytic. and other industrial processes

through the application of

cogeneration and highlights the

advantages--and possible pitfalls for the unwary--of such installations. The paper reviews the steps leading up to a commitment to investigate the application potential further, and outlines the options open to the would-be owner/operator for financing, sale of excess steam and/or power, fuel contracts, fuel sources, and interfaces with utilities, thirdparty owners and the lending institutions.

(9:00 a.m.) ENERGY CONSERVATION IN THE TANKHOUSE AT COPPER REFINERIES PTY. LTD., TOWNSVILLE: J. O'Kane, S. K. Kim, Z., H. Meka, of Copper Refineries Pty. Ltd., Townsville, QJ,eensland, Australia. Copper refining process electrolytes are maintained in the range 60-65°C to ensure an efficient and viable operation. The heat energy required to meet these temperatures has been traditionally derived from the natural electrical energy required to drive the process and supplementary steam energy. In 1983, experiments were conducted at Copper Ref ineries Pty. Ltd. to determine the effects of insulating the Tank House cells, and fully covering the cells. The results of these experiments showed conclusively that minimal steam would be required to maintain electrolyte temperatures. These positive results concluded in an Energy Conservation Programme for the Tank House I and this was implemented in 1984. A computerised cell cover monitoring system was developed t and incorporated to control cell coverage and fluid balance. The experimental

work and the benefits obtained since implementation of the programme are discussed.

(9:30 a.m.) POSSIBLE ENERGY SAVINGS IN EXISTING Cu TANKHOUSES, K. Hena, Metallurgi. Hoboken-Overpolt, B-2430 OLEN, Belgium.--Amonglt a numb.r of pOllibilitio. to reduce the energy conlumption in an exilting Cu tankhoulO, the cell covering, the improvemant of tha geometry of the electrocleo and the uae of an IRIPS Icanner for Ihort-circuit cletection are elucidated. Steam conlumption, which in the OlIn tankhoull Itood for 45~ of the anergy cOlt, wal decrealed by 12.5% uling coven on the cell.. One of the main gainl of the u.. of Contilanod conliltl in the pOllibility to ule thicker anod.1 at the lame Ipacing &I conv.ntional anodel to achieve a consid.rabl. incr.... in current efficiency and a lower cell volt.ge. Th. rllulting low.r Icrap-ratio maans a conliderable gain on remelting energy. The, uae of an IRIPS Icanner for Ihortcircuit cletection leacll to important lavingl on manpower and energy consumption.

(10100 a.IIl.)

Break

(10:30 a.m.) REVIEW ON RECENT COPPER REFINING TECHNOLOGY IN JAPAN AND PROGRESS OF COPPER REFINING SYSTEM OF MITSUI MINING AND SMELTING CO., LTD: Yukio Sakoh, Mitsui Mining & Smelting Co., Ltd., 2-Chome, Nihonbashi, Muromachi, Chuo-Ku, Tokyo, Japan; Katsuhiko Inagaki, Tamano Smelter, Ribi Kyoclo Smelting Co.,

(11 :30 a.m.) TIlE ILC =roLYTIC COPPER REFINERY. DESIGN FFA'IURES AND OPERATION, H. walqui, J. Rodriguez, an:i V. Alarcon, Minero Peru Cower Refinery, no, Peru. The Ho Electrolytic Copper Refinery located at the Southern p;rt of Peru, in the city of Ho, started its operation in 1975 with a design capacity of 150,000 Ml'/year of copper cat1"
EXTRACTIVE METALLURGY OF IRON TMS-AIME General Abstract Session Wednesday, February 27, 1985 8:30 a.m.

Dominion B Sheraton Centre

Session Chairman: Madhu Ranade, Inland Steel Research Lab., Mills Station, 9-000, East Chicago, IN

(8:30 a.m.) STUDY ON THE SINTERING BEHAVIOUR OF MOUNT WRIGHT SPECULAR HEMATITE CONCENTRATE: S.C. Panigrahy and M.R. Rigaud, Ecole Polytechnique. Montreal, Quebec, Canada H3C 3A7. There appears to be an unreasonab Ie bias aginst the use of Specular Hematite Concentrates in the production of sinter. Investigation on the sintering behaviour of Mount Wright Specular Hematite showed that this concentrate can be successfully sintered. By choosing proper sinter mixes and commonly used adclitives, sinter of good quality can be obtained without adversely affecting the production rate. One can take advantage of the high iron and low A1 20 S content of Mount Wright concentrate for blending, in particular, with the most abundant aluminous ores to obtain sinters of desirable quality.

(8:50 a.m.) THE INrLUENCE Or THE CARBDNMONOXIDE-CAR90NDIOXlDE AND SOLID CARBON SYSTEM ON THE MELTING PATTERN Dr SINTER AND PELLET.'

K. ~zcBn, EticBnk, Anken, Turkey and H.W. Gudeneu, RWTH Aechen, ~many.

The effect of the carbon containing reducing agent on the melting proporties of sinter end pellet under constant heating rate is investigsted ",ith gravimetric method. The result obtained is that the melting pst tern depende on the formation of reaction fronts in the single grain. Therefore, the melting pattern is explained ",ith reduction degree and grain morphology at melting start temprature. The experimental reeu1 ts conform properly to the presented "T",o layer sphere model". It is possible to describe the scrap-and sponge iron smelting ",ah other modified models. After serial connection of a second el,ectronic balance to the existing one, the emelting of the primary slag on to coke, primary slag-coke reaction, and the dropping through the coke are observed. The liquid solid reaction rste at elevated tempratures is 10",er as expected, eo ironoxide containing primary slag goes on to flo", through coke burden. "This ",ork ",as supported by NATO Research Funds and DFG.

Ltd. , Japan.

Similar to other industrial fields, copper smelting ancl refining technology in Japan has rap icily progressed in this thirty (30) years and has reachecl an eminent level in the world. In this paper, the progress of copper refining technology in Japan is reviewed. Also distinctive Periodic Reverse Current (PRC) electrolytic system and som~ energy saving technologies for copper refinery developed by Mitsui Mining and Smelting Co., Ltd., are presented.

(9: 10 a.m.) SMELTING OF KOREAN TITANIFERROUS MAGNETITE ORE IN A THREE ELECTRODE ARC MELTING FURNACE: Dae S. Kim, Yong U.Choi, Joon S. Kim and Suk J. Im, KIER 219-5 Garibong,Guro Gu, Seoul, Korea. DepOSits of titaniferrous magnetite ore occuring in Korea are estimated to be seven million tons. The

66 - TMS-AIME Annual Meeting Program ore contains about 20 % Ti02 and 49 % Fe. To obtain pig iron and Ti02 enriched slag suitable as a chlorination feed to produce Ti metal or Ti02 pigment, pellets consisting of ground ore (minus 48 mesh) ~ metallurgical coke and soda ash were smelted in a three electrode arc melting furnace. A series of tests were conducted to determine the effects of smelting temperature, ratio of ore to coke, addition of fluxing agents and smelting time. The content of Ti02 in the slag and pig iron were respectively 55 % and less than 0.03 %. The Ti02 content in the slag is further upgraded to greater than 90 % for the chlorination feed by other means.

structures even in nominally homogeneous base metals. Each of these cases may result in enhanced stress corrosion cracking susceptibility in the presence of sufficiently aggressive environments and either applied or residual tensile stresses. This presentation will discuss the role of microstructural variables in the sec susceptibility of alloys with particular attention to ferrous alloy systems. The role of chemical segregation of elemental species to interfacial boundaries will be particularly addressed, and related to the sec phenomenon.

(9:10 a.m.) COMPARISON OF CAVITATION IN STAINLESS STEELS WITH DIFFERENT CREEP DUCTILITIES:* J. H. Schneibel, t L. Martinez, tt and C. L. White. t

(9:30 a.m.) ~;\lG:,

l:~

tMetals and Ceramics Division, Oak Ridge National Laboratory, 37831. ttlnstitute of Physics, National University of Mexico, A. P. 20-364, 01000 Mexico, D.F., Mexico. P. O. Box X, Oak Ridge, TN

LI'..',urr. m('U ANT:, ITO

Dept. ,

Abol-Hassan K. Abdel-azlz, ,ac. r;ngineering, University of Alexandria,

Folytherms of some properties of lirmid iron show a sudden change in each property at a temperature in the range of 1620 - 1650 or:. ~:lmj lar behavior is observed wi th mol ten dilute iron-base allays. ';'hese features confirm a proposal of the existence of a tempera ture-induced structural chanee in liquid iron, wi th subsequent reflections on the properties of the mol ten alloys. corresponding features are also observed in the effect of temperature on some iron- and steel-making reactions.

The evolution of the grain boundary cavity population in Fe-IS wt % Cr-IS wt % Ni stainless steels with and without 1% antimony was studied metallographically. Employing grain boundary diffusivities obtained from Coble creep measurements, the cavi ty size distributions are compared to several growth models. Reasons for the low creep ductility of the antimony-doped alloy are discussed.

*Research sponsored by the Division of Materials Sciences, U.S. Department of Energy under contract DE-ACOS-840R21400 with the Martin Marietta Energy Systems, Inc.

(9:50 a.m.) MOLECULAR DISSOCIATION .AND REFORMATION ON METALLIC SURFACES DURING GAS-SOLID REACTIONS: E.S. Lambers

arId J.S. Foster, Dept. of Materials Engineering, University of Florida, Gainesville, FL 32611 There is substantial evidence that many gas-solid reactions proceed through gas molecule dissociation and reformation (MDR) on the solid surfaces. In MDR arriving molecules adsorb and dissociate, forming adsorbed atomic species which may recombine to form new adsorbed gas molecules that desorb, becoming product gases. One atomic species may participate in the rate controlling step for the overall reaction. Thus, it is important to understand MDR and how it influences the dynamic populations and states of the atomic species. Experimental evidence supporting MDR versus other views will be discussed with emphasis on contributions from modern surface science research. Examples of MDR in oxide reduction and in metal carburization and oxidation will be presented.

(9:30 a.m.)

SOLID CA[)1IUM EMBRITTLEMENTOF .ZIRCALOY-2: R. P. Gangloff; Exxon Research and Engineering Company, CRSL, Route 22 East, Annandale, Neloi Jersey 08801

FRACTURE I TMS-AIME General Abstract Session

Textured Zircaloy-2 is embrittled by solid cadmium during plane strain tensile deformation at 573 K. Cd induced cracking initiates near the alloy yield strength and propagates by near-basal plane cleavage in contrast to high strain, equiaxed dimpled rupture for a vacuum envi ronment. Inc reased plast i c st rai n is required for Cd embrittlement of Zr-2 as the applied load axis is rotated from perpendicul ar to parallel to the maximum concentration of basal planes in textured specimens. Solid Cd embrittlement is strongly time dependent. Measured increases in fracture elongation with increasing loading rate are mode~ed 2ased on Cd surface diffusion with a diffusivity of 2 x 10- cm /sec. The time dependence for embrittlement is inconsistent with rates of Cd evaporation and vapor transport. Cd-crack wall interactions 1imi t vapor trans port, res ul t i ng ins urface diffus i on cont ro 1 of crack propagation. Copper additions to cadmium inhibit embritt 1ement of Zr-2 due to either a reduct i on ins urface diffus i vi ty or to competitive adsorption.

Wednesday, February 27, 1985 8:30 a.m.

(9:50 a.m.)

Commonwealth Room Sheraton Centre

Session Chairman: J. Lankford, Southwest Research Institute, 6220 Culebra Road, P.O. Drawer 28510, San Antonio, TX 78284

EVALUATION OF THE FRACTURE TOUGHNESS OF SHIELDED METAL ARC WELDS FOR OFFSHORE STRUCTURE APPLICATIONS: J.E.M. Braid and

J .A. Gianetto, Physical Metallurgy Research Laboratories, CANMET, Ottawa, Canada. KIA OGI

(8:30 a.m.) EFFECTIVE GRAIN SIZE OF DUAL PHASE STEEL:

N. J. Kim, Dept. of

Mechanical Engineering, University of Wyoming, Laramie, WY 82071 and A. H. Nakagawa, Westinghouse Electric Corp., Marine Division, Sunnyvale, CA 94088. The effect of martensite morphology on the tensile properties of dual phase steels is relatively well understood. However, its effect on the cleavage fracture behavior of dual phase steels is not yet clear. Results are presented of a study to establish this effect for two different microstructures. Scanning electron fractography of broken Charpy impact specimens showed that the cleavage facets of the intermediate quench steel were much larger than those of the intercritical anneal steel. This corresponded well with the impact energies and the transition temperatures. SEM observations of cross sections of the fracture surfaces showed that cleavage cracks were deflected mainly at ferrite grain boundaries rather than at ferrite/martensite interfaces. These results are explained in terms of the orientation relationship between the ferrite and martensite as determined by electron microdiffraction.

(8:50 a.m.) MICROSTRUCTURAL EFFECTS ON STRESS CORROSION CRACKING OF WELD-

MENTS:

D.J. Duguette, Rensselaer Polytechnic Institute, Troy, New York, 12181

The microstructures of weldments and associated heat affected zones are often mechanically and chemically quite different from the base metal which is joined. In some cases these microstructures are intentionally different in order to assist in controlling joining problems such as hot cra.cking, in other cases the chemistry of the weld is chosen to control potential galvanic corrosion problems and, in still other cases, the rapid cooling of the weld metal and heat affected zone result in metastable

A range of 20 shielded metal arc welding electrodes from various manufacturers have been evaluated for their suitability in the fabrication of offshore oil and gas structures for Canada's east coast and arctic regions. The study included C-Mn and C-Mn-Ni consumables which were used in the vertical-up, 3-G, position in a procedure which maximized the as-depOSited weld metal in order to better differentiate between the various manufacturers. COD testing was conducted at temperatures consistent with envisioned design temperatures for Canadian offshore regions; -IOoC, -30°C and -50°C with -IO°C as a comparison with work from North Sea developments. Typical CVN results showed 40J at -40°C, however, COD results indicated marginal toughness at -30°C. These results were evaluated in terms of weld microstructural features such as inclusion size distribution and type and amount of transformation products. Improvements in comsumable design are discussed.

(10: 10 a.m.) I NFLUENCE OF MICROSTRUCTURE ON QUAS I-STAT I C DUCT I LE FRACTURE IN AI-Li ALLOYS: ROLE OF CRACK GEOMETRY': S. Suresh, Division of Engineering J Brown UniversitYJ Providence, RI 02912 and A.K. Vasudevan, Alloy Technology Division, Alcoa Center, PA 15069

The influence of microstructure on fracture behavior is examined in AI-2.1 Li-2.9 Cu-0.12 Zr alloy. It is found that variations in precipitation and slip characteristics, due to the aging treatments, promote substantial differences in the fracture rrorphology during quasi-static failure. Accordingly, a crack path-modified stress intensity factor is used to characterize microstructurallyinfluenced fracture touahness and this modified fracture parameter is found to be i ndepend~nt of yi el d strength over a range of microstructural condition. Correlation between microstructural variations and fracture path are explored. *This work was sponsored partly by Brown University MRL Grant DMR-3216726 and partly by NAVAIR Grant NOOOI9-80-C-0565.

TMS-AIME Annual Meeting Program - 67 (10:30 a.m.) INTERFACE FRACTURE OF PLANAR INTERFACES, Ri cky Barrera, Lloyd Brown and H.L. Marcus, Department of Mechanical Engineering/ Center for Materials Science and Engineering, The University of Texas, Austin, TX 78712 This paper will describe research on the fracture of planar interfaces. Included in the systems discussed will be metal/ oxide/metal and metal/oxide/ceramic laminated materials. The interface fracture is related to the chemistry, structure and electronic state of the interfaces.

HERBERT H. KELLOGG SYMPOSIUM: Copper Sponsored by The Physical Chemistry Committee and The Copper, Nickel, Cobalt and Precious Metals Committee Regency Ballroom Sheraton Centre

Wednesday, February 27,1985 8:30a.m.

*Thi s research was supported under ONR contract N00014-83-K0143.

Session Chairmen: N. J. Themelis, Columbia University, New York, NY 10027 S. J. Warner, INCO Ltd., J. Roy Gordon Research Lab., Sheridan Park, Mississauga, Ontario, L5K lZ9, CANADA.

(10:50 a.m.)

(8:30 a.m.)

THE EFFECT OF MICROSTRUCTURE ON THE FRACTURE OF PH 13-8 Mo MARAGING STAINlESS STEEL: J. A. Daniels, J. H. Steele, Armco Inc., Middletown, Ohio, 45043; N. Jayaraman, University of Cincinnati, Cincinnati, Ohio, 45221-0012. Microstructural development during isothermal aging of PH 13-8 Mo, a maraging stainless steel, has been studied for controlled variations of nickel and carbon in the alloy chemistry. Correlations between several microstructural features and age hardening behavior have provided a basis for examining their effect upon fracture and fracture toughness. Microstructural features which were considered include prior austenite grain size, the lath martensitic substructure, precipitated carbides, and reformed austenite. Changes in these features were characterized using TEM, SEM, and X-ray diffraction after isothermal aging at 510, 538, and 576°C. Relative fracture toughness properties obtained from Charpy transition temperature data will be presented and correlated with changes in each of the microstructural features. The results will be discussed in terms of the micromechanisms of fracture which control toughness at the higher strength levels developed in this alloy.

(11 :10 a.m.) EFFECT OF NEUTRON FLUENCE ON THE FRACTURE PROPERTI ES 0 F HT·9 WELDS: *F.H. Huang and D.S. Gelles, Westinghouse Hanford Company, Rl chl and, WA 99352 Fracture toughness tes ts us i ng el ectropotent i a 1 techn i q~~s on 2 HT-9 weld material irradiated to a fluence of 2.35 x 10 n/cm (E>O.l MeV) at 390°C were performed at 93, 205, 316 and 427°C. Testing of welds irradiated at 450, 500 and 500°C was performed at 205°C. Test results were analyzed using the J-integral approach. It was found that the fracture toughness of these HT-9 welds increased slightly, while the tearing modulus decreased significantly after irradiation to a.flue~ce.of 2.35 x lOa n/cm 2 . In addition, results showed that lrradlatlon temperature had little effect on the fracture toughness of HT-9 weld metal. After the test, the specimens were examined by scanning electron microscopy in order to understand the fracture process in this weld material. *This work was supported by the U.S. Department of Energy.

(11 :30 a.m.) EFFEcrs CF Mn AND Cr 00 INrER:;RANULAR SffiREXiATIOO AND EMBRITI'LE-

Mmr IN P-OOPED I~*.

we~ Yu-Qi~ and C. J. McMahon, Jr., Dept. bf Mat. SCience an:! ~., Univ. of Penna., Phlla., PA 19104.

1he effects of Cr and Mn on the intergranular segregation of P in iron arw::I on p-induced intergrarular anbrittianent haIIe been studied by means of AUger electron spectroscopy an:! by measuranent of the stress to initiate intergrarular fracture

in specimens before and after a decarburization treatment. The rem:lval of carbon was found to. increase the arount of P segregation duri~ agei~ at 480°C 'and to reduce the intergranular fracture stren;,th. !he presence of Mn was found to increase the aroount of P segregation, an:! an increase in P content increased the lIIPUnt of Mn segre;Jation. !hus. interactive cosegregation between these elanents, a la Guttmann, was established. !he presence of Mn caused a greater reduction in intergranular fracture stre~th than was found for Palone. No evidence for cose;Jre;Jation of Cr an:! P was found at Cr an:! P levels up to 2% and 0.06%, respectively. However, sane evin..nce for Cr segre;Jation per se was found. "This research was supported by NSF grant No. ~ 83-11974.

PREDICITON OF PARTICLE BEHAVIOR DURING FLUID BED ROASTING OF COPPER SULFIDE CONCENTRATES: C. A. Natalie, J. P. Hager, and T. Li, Colorado School of Mines, Dept. of Met. Engrg., Golden, CO 80401 Most work on characterization of particle residence time during fluidization has been done on uniformily sized particles. Metallurgical processes, however, u6uali y deal with feed materials with a wide size distribution. This paper reports on the experimental measurement of residence time distribution for various particle size intervals during fluid bed roasting of copper sulfide. The experiments were done in six inch diameter, continuous fluid bed roaster. The experimental results are compared to results predicted by computer modelling.

(9:00 a.m.) RATE PHENOMENA IN THE OUTOKUMPU REACTION SHAFT: N.D.H. Munroe ,Henry Krumb School of Mines, Columbia University, New York, NV 10027, J. ~akinen, Outokumpu Oy, SF-29200 , Harjavalta, Finland, and N.J. Themelis,Columbia University.

In the last two decades. the Outokumpu flash smelting process has become the dominant new technology for copper smelting and has also been applied to the smelting of other metal sulfides. The application of oxygen enrichment, higher blast temperatures and improvements in burner and furnace design have resulted in ever increasing smelting rates per unit volume of the reaction shaft. The current state of evolution of the Outokumpu f I ash smel t.ing technology and its future potential are discussed, ~ith particular reference to the rate phenomena taking place in the reaction shaft of the f.urnace.

(9:30 a.m.) Overall Kinetics of Chalcopyrite Oxidation: P.C. Chaubal and H. V. Sohn, Department of Metallurgy and Metallurgical Engineering, University of Utah, Salt Lake City, Utah 84112-1183. The overall kinetics of oxidation of chalcopyrite have been studied for temperatures upto 1273 K. The experiments were conducted in a stationary bed reactor using a nonisothermal technique. Any mass and heat transfer effects on the kinetics of oxidation were el iminated by using a high enough gas flow rate. Upto temperatures of 873 K the pore-blocking kinetics were appl icable, whereas above 873 K, the power-law kinetics gave a satisfactory' fit of data. The activation energy was 218 KJ/mol below 754 K and 23.7 KJ/mol above 1060 K. Predominance area diagrams were constructed at various temperatures and used in conjunction with X-ray analyses of the partially oxidized samples to determine the intermediate phases formed during the reaction. The analysis also provides a justification for the kinetic model s used. The resul ts indicate that the reaction rate is first order with respect to the oxygen concentration and inversely proportional to the square of the particle size throughout the ranges of temperature studied. *This research was supported by NSF under Grant No. CPE-8204280. (10:00 a.m.) PROGRESS OF COPPER SULFIDE CONTINUOUS SMELTING:

Takeshi Nagano, President, Mitsubishi Metal Corporation 5-2, Ohteinachi I-chorne, Chiyoda-ku, Tokyo 100, JAPAN Copper pyrometallurgy in Japan has experienced qui~e fundamental changes in last fifteen years. The severe environmental restriction coupled with increase of energy costs accelerated the developnent work of the new continuous process in Hi tsubishi Metal Corporation. After several years of pilot plant test work the commercial plant was put into operation at Naoshima SUtel ter in 1974, the design capacity of which was 4,000 ton of copper per month. Many modifications and improvements have been incorporated into the process and 7,200 ton per month of copper production was achieved in 1983, proving that continuous process was much more economical than conventional process It is now possible to design and operate the continuous process in wide range of capacity. This paper will review the process and make the cost and energy comparison between Hitsubishi COntinuous and Conventional Processes. 4

68 - TMS-AIME Annual Meeting Program (10:30 a.m.)

(8:55 a.m.)

TOWARD A BASIC UNDERSTANDING OF AIR INJECTION IN THE COPPER CONVERTER: J .K. Brimacombe, A.A. Bustos arid G,G. Richards, Department of Metallurgical Engineering, The University of British Columbia, Vancouver, B.C. V6T lWS CANADA.

S inee the Peirce-Smith converter was introduced to the nonferrous industry over seventy years ago, the air-injection system has undergone little change and research on submerged injection in the converter has been lacking. Recent progress in understanding the gas discharge dynamics and Qxygen/bath reaction kinetics are reviewed and the results of recent in-plant trials are presented. It is shown that with current blowing pressures, air discharges from the row of tuyeres into the bath as ~n unstable, horizontal gas envelope due to the overlap of bubbles forming at adj acent tuyeres. The behaviour of the unstable gas envelope contributes to accretion formation and tuyere blockage; this has been observed directly with the aid of a tuyerescope. Tuyere blockage, and the necessity of punching tuyeres can be prevented by raising the injection pressure to achieve underexpanded flow conditions in the tuyeres. Finally it is shown that high oxyg'en utilizations are achieved 1n the copper converter because the oxidation kinetics are governed by gas-phase mass transport.

(11 :00 a.m.) TECHNOLOGY OF SECONDARY COPPER SMELTING AND REFINING:

W. R. Opie, AMAX Base Metals R&D, Inc., 400 Middlesex Ave., Carteret. NJ 07008 Fundamentals of blast furnace smelting of low grade copper and precious metal scrap and residues are reviewed with emph~sis on emission control, by-products produced, slag cleaning for high recovery of metal values and the evolut ion of an off-gas system to eliminate hydrocarbons that result from decomposition of plastics in the blast furnace charge. Problems with tin, antimony and nickel in the smelter-refining cycle are discussed.

(11 : 30 a. m. )

LEACHING OF GALENA IN HYDROCHLORIC ACID SOLUTIONS SATURATED WITH SULFUR DIOXIDE: M.K.Han, M.E.Wadsworth, IJept. of Metallurgy and

Metallurgical Engr., University of Utah, Salt Lake City, UT 84112 Galena leaches non-oxidatively in hydrochloric acid solutions producing dissolved lead and H2S gas. When S02 is present in the solution, H2 S reacts readily with S02 to produce solid elemental sulfur. A kinetic study for the dissolution of galena in hydrochloric acid solutions saturated with SO was made using rotating discs, and was applied to complex suffide concentrates which contain in addition to lead, sulfides of zinc and copper. Tests were carried out at ambient atmospheric pressure and temperatures below boiling point. Experimental variables studied include rotation speed, temperature, partial pressure of S02' pH, and chloride ion concentration. Results show that the reaction follows a linear rate with an activation energy of 14 KcaL The rate with S02 present in the solution was faster than that without S02. SEM photographs of the reacted surface indicate that sulfur grows in spherical form and does not form a protective layer. Results from concentrate leach show an excellent selectivity for galena.

(9:20 a.m.) KINETICS OF LEACHING OF MOLYBDENITE IN CHLORINE SATURATED SOLUTIONS: Say Wenching and M. E. Wadsworth, Department of Metallurgy, University of Utah, Salt Lake City, Utah. The rate of dissolution of molybdenite (MOS 2 ) was measured in aqueous chlorine solutions. Mix potentials developed by chlorine gas were sufficiently high that molybdenite dissolved rapidly without passivation. Under conditions of high Cl flow rate, the kinetics were controlled by the reaction of tfie molybdenite at the edge of individual platelets. This was deduced by analysis of rates of reactions for several size fractions. A model for the leaching of molybdenite in chlorine is presented which accounts for chlorine concentration, particle size distribution, and temperature.

(9:45 a.m.)

THE BEHAVIOR OF ARSENIC AND ANTIMJNY IN THE SOLIDIFICATION AND ELEX;TROLYSIS OF NICJ 15, Finlani.

In the first part of this paper the behavior of small anounts of :impurity elanents in COfpEll' anodes is studied. The practical

solidification of the anodes is canpared with the equilibrium diagrams ani kinetic factors. In the second part the electrolysis of the anodes in the sulfate-based electrolytes is discussed. To clarify the distribution of the :impurity elanents in the anode, the structures were studied after the solidification ani the electrolysis of the anodes. This examination was carried out

wi th optical microscope, scanning electron microscope ani electrochemical rreasuranents.

COPPER AND IRON SPEC lATIONS DURING BATCH LEACHING OF CHALCOPYRITE BY AQUEOUS CuCl 2 , HCl AND NaCl: M. L. 0 'Malley and

K. C. Liddell, Washington State University, Pullman, VIA 99164. Particulate chalcopyri te was leached by solutions containing CuC1 2 , Hel and NaCl. Total Cu and total Fe concentrations were determined by atomic absorption. A visible spectrophotometric method was used to analyze far Cu(II) and Fe(III). Leaching was allowed to continue in a batch reactor until there were no further changes in any of the four concentrations measured. The observed Cu(I)/Cu(II) ratios are explained in terms of the redox and complexation reactions in the solution. Differences in the leaching behavior of CuCl -RCINaCl and FeCl 3-HCI-NaCl media are discussed. 2

(10 :10 a.m.)

3reak

(10:25 a.m.)

HYDROMETALLURGY/CHEMICAL PROCESSING III Sponsored by the Joint TMSISME AIME HydrometallurgylChemical Processing Committee Wednesday, February 27, 1985 8:30 a.m.

Senate Suite Sheraton Centre

Session Chairpersons: Knona C. Liddell, Department of Chemical Engineering, Washington State University, Pullman, WA 99164; Gary W. Warren, Department of Metallurgy, Carnegie· Mellon University, Schenley Park, Pittsburgh, PA 15213

TITANIUM AND IRON SPECIATIONS IN HYDROCHLORIC ACID SOLUTIONS AND THEIR RELATIONSHIP TO ILMENITE LEACHING: M. Moore, R. Orth

and K. C. Liddell, Washington State Uni versi ty, Pullman, WA

99164. USing equilibrium constants from the literature, speciations of- titanium and iron in hydrochloric acid solutions were calculated. Reactions considered were oxidation of Ti(111) by Fe(III), hydrolysis of both Ti and Fe, and formation of chloro complexes of Ti and Fe. 02 was assumed to be excluded from the system. Implications for the leaching of ilmenite by Hel are discussed and compared with the results of leaching experiments run in a batch reactor.

(10:50 a.m.) (8:30 a.m.) THE DISSOLUTION OF GALENA IN FERRIC CHLORIDE MEDIA:

J.E. Dutrizac, CANMET, 555 Booth Street, Ottawa, Canada KlA OGl.

DISSOLUTION CHEMISTRY OF NICKEL ARSENIDE MINERALS:

P. Kondos and

G.P. Demopoulos, Dept. of Mining and Metallurgical Engineering, McGill University, 3450 University St., Montreal, Quebec, Canada H3A ZA7

The dissolution of galena (PbS) in ferric chloride (0.01-2.0 M)hydrochloric acid (0.1-6.0 M) media has been investigated over the temperature range 30-10QoC and for alkali chloride concentrations from 0-4.0 M. Rapid parabolic kinetics were observed under all conditions together with an activation energy of about 10 kcal/mol. The rate was found to decrease steadily with increasing FeCI) concentrations )0.1 M, but to increase with increasing concentrations of the FeC1z reaction product. Most significantly the dissolution rate decreased sharply and linearly with increasing concentrations of PbC1Z in the leaching medium. Elemental sulphur accounted for ,.95% of the oxidized sulphide ion provided the initial acidity was low enough to avoid HZS evolution. It is shown that the dissolution reaction is governed by the outward diffusion of the PbCl2 reaction product through the constantly thickening elemental sulphur layer formed on the surface of the galena.

The newly discovered high grade uranium ores of Northern Saskatchewan, Canada impose a unique problem to the hydrometallurgist due to their complex and uncormnon composition. The uranium grades are high and the uranium minerals are intimately associated with nickel arsenide minerals such as niccolite (NiAs), gersdorffite (NiAsS). and raDlllelsbergite (NiASZ).

Similar pro-

blems are also anticipated when base metal sulphide concentrates containing arsenide minerals have to be subj ected to hydrometallurgical processing. Thus an understanding of the leaching and solution chemistry of these nickel arsenide minerals in both sulphate and chloride media is greatly needed. To this end, leaching tests with individual specimens of these minerals were conducted to establish their dissolution chemistry (thermodynamics, kinetics and solubility) under simulated uran.ium acid leach conditions.

TMS-AIME Annual Meeting Program - 69 (11 :15 a.m.)

THE EFFECT OF POTENTIAL FLUCTUATIONS ON THE MORPHOLOGY OF ZINC ELECTRODEPOSITS: V. Jiricny, T. Huh and J. W. Evans, Department of Materials Science &: Mineral Engineering, University of California, Berkeley, Berkeley, CA 94720 The use of periodic current reversal (peR) to improve the per formance of electrowinning cells is well-known. peR is but one example of metal deposition under conditions of fluctuating potential; another example is the deposition of metal in fluidized bed electrodes where the fluctuation of particle potential is inherent to the electrode. A rotating disc electrode has been used to study the morphology of zinc deposited from various electrolytes (including impure acid electrolytes typical of zinc electrowinning). The electrode is driven by a computer controlled potentiostat permitting deposition at constant potential or with any ar'pitrary potential fluctuations. Deposits have been examined by scanning electron microscope and reveal that the morphology is

greatly influenced by the potential fluctuations.

LEAD, ZINC, TIN I: SECONDARY PROCESSING OF LEAD AND ZINC Sponsored by the TMS Lead-Zinc-Tin Committee Wednesday, February 27, 1985 8:30 a.m.

Princess Ballroom Sheraton Centre

Session Chairmen: J. M. Cigan, St. Joe Minerals Corporation, P.O. Box A, Monaca, PA 15061; V. Ramachandram. ASARCO Inc., 901 Oak Tree Road, South Plainfield, NJ 07080

(8:30 a.m.) ELECTROL YTIC PROCESS FOR tHE RECOVERY OF LEAD FROM SPENT ELECTRIC STORAGE BATTER1ES. U.Ginatta, Elettrochimica Marco Ginatta S.p.A., Via Brofferio 1-10121 Torino, Italy The important features of the "G.S." Process are: - production of 99.9% lead cathodes directly from spent batteries by electrolytic dissolution; - the completely automatized version of the plant has a total energy consumption of 1,000 kWh/ton of lead produced; - all the lead values contained in the batteries are recovered; - antimony is separated as anodic mud and recovered as oxide; - no crushing of batteries is required; - is intrinsically clean with no air or water pollution, no production of slag, drosses, etc. and exceeds EPA and OSHA lowest limits; - it has eliminated the last pyrometallurgical operation, the casting of ingots, since stripped cathodes are sold directly to the lead products manufacturers; - floor space is limited since tanks are 2.5 meters deep) and cathodic current density is 400 A/m 2 .

(9:00 a.m.) SECONDARY LEAD PROCESSING AT J1)S ANGELES PLANT OF GNB BAITERIES, INC.: Robert L. Smith and Kenneth G. Clark, GNB Batteries Inc., Los Angeles, CA; Andrew R. L;lrson and E. Kent Hudson, GNB Batteries Inc., Metals Division, St. Paul, MN.

Early in 1982 the new 50,000 metric ton per year Los Angeles secondary lead plant of GNB Batteries Inc. was put into operation. Metallurgical design of this plant incorporates a proprietary mechanized feed preparation system for battery breaking and component separation. Scrap batteries are received either palletized or in bulk and are conveyed to ~ hal'¢mermill for breaking. Grid metal, paste material, case material, and spent electrolyte are separated and individually recovered. The grid metal and paste material are smelted indiVidually or collectively in a reverberatory furnace and the slag produced is smelted in a blast furnace. Bullion is refined pyrometallurgically for the production of soft lead and lead alloys. Metallurgic.al baghouses and a soda ash scrubber are used to control emissions from the furnaces. Process control is partially automated and product quality is controlled using a direct-reading emission spectrometer.

load di oxi de are deposited on the anodes. A major break through was achieved in this work with the dis,overy that lead dioxide formation at the anodes is prevented by the addition of a small amount of phosphorus to the electrolyte. High-purity lead (99.99+ pet) was recovered from electrowinning experiments conducted in I-liter and 20-liter multielectrode cells.

(10:00 a.m.) SCANDUST, THE FIRST COMMERCIAL PLASMADUST PLANT FOR RECOVERY OF ZINC FROM SECONDARY MATERIALS: Erik CavalliBjorkman, Project Manager, SKF Steel Engineering, Sweden; Sune Eriksson, Manager, Non-Ferrous Projects, SKF Steel Engineering, Sweden; Hans Herlitz, Manager Engineering Department, SKF Steel, U.S.A. SKF Steel Engineering has pioneered the development and use of metallurgical applications of plasma technology. Since 1981 a PLASMA RED plant for production of 50,000 tons of sponge iron per year has been in operation at SKF Steel's Hofors plant in Sweden. In the middle of 1984, a commercial PLASMADUST plant for smelting of baghouse dust and other secondary raw materials was started up. This plant has a smelting capacity of 70,000 tons of electric arc furnace dust per year and is equipped, with three 6 MW plasma generators from SKF Steel. This paper gives a review of the PLASMADUST concept for smelting of secondary zinc bearing raw material 'ind reports some of the experiences from the running-in of the Scan Dust piant in Landskrona, Sweden.

MICROSTRUCTURAL CONTROL DURING ALUMINUM ALLOY PROCESSING I: Deformation, Recovery and Recrystallization Sponsored by: TMS Non-Ferrous Metals Committee Wednesday, February 27,1985 8:30 a.m.

Monarch Sheraton Centre

Session Chairmen: E. H. Chia, Southwire Company, P.O. Box 1000, Carrollton, GA 30119; H. J. McQueen, Concordia University, Montreal P.Q. H3G 1MB, Canada (8:30 a.m.) "METAL FIJloI lIND MICOCSTRUCIURE IN AUJMINUM DEFORoIATIoo PKX;E:SSING" , R,N. Wright, Renssalaer Polytechnic Institute, Troy, New York, and E.H. QUa, Soutl-Mire Q:npany, P.O. Box 1000, Carrollton, GP. 30119.

'lhe evolution of the microstructure in deformation processing is a direct consequence of the process strain, strain rate, and temperature. I-breover, the microstructure manifests itself in the flaN stress which, in turn, is directly related to process loads. 'fuus, it is necessary to consider fundarrental process rrechanics in any intezpretation of microstructural evolution. 'lhe basic rretal flaN in rolling, extrusion, and drawing will be considered with enphasis on processing loads, deformation zone gearetry, friction, redurrlant work, and internal. stress state. Deformation and frictional heating will be reviewed. 'lhe relationship of these perspectives to dynamic/static recovery/recrystallization will be discussed and exarrples drawn fran laboratory and ccrrmercial processing of altuninum and aluminum alloys.

(9:00 a.m.) "Har OORKJN:; lIND STATIC REX:RYSTALLIZATIoo OF Al AND Al-M:j ALIDYS" , H.J. McQueen*, (booordia University, M::>ntreal P.Q. H3GlM8, canada and N. RyunI, Physical Metallurgy Inst., Norges Tekniske H¢gskoie, N 7034

Trondheim Nrn, Norway. 'Ibrsion tests were carried out at strain rates of 0.41 and 0.82s- 1 on 260°C. 'lhe flaN curves attain a steady state reg:ine which increased with M:j content and were nuch lo.>er than for ca:rrercial alloys. 'fue strain rate has a hyperbolic-sine stress-dependence and an Arrhenius type 1:atperature-dependence with activation energy close to that for self diffusion, but increasing with M:j content. Subgrain size waS observed to increase with test taIperature and to decrease with rising M:j content. 'lhe static recrystallization after hot working during holds at tatperature (above 350°C) was observed by rretallography and also by decrease in flON stress. {)pJn addition of l-\:i the rates of recrystallization decreased fran that of Al, yet were nuch faster than OCfIIIErCial materials. 'lhe kinetics follONed the rx:mral Avrami equation with K values of 2.9 and 3.6.

(9:30 a.m.)

ELECTROLYTIC RECYCLING OF SCRAP BATTERIES: A. Y. Lee, E. R. Cole, Jr., and D. L. Paulson. U.S. Department of the Interior, Bureau of Mines, Rolla Research Center, Rolla, Mo. Research by the Bureau of r~ines has res"ulted In a combination e1ectroreflning-e1ectrowinning method for recycling lead from scrap batteries. The lead metal grids and lugs are separated from the sl udge by ball mill i ng, washi ng, and screeni ng and are melted and cast into anodes for e1ectroreflning by the Betts process using waste fluosilicic acid as the electrolyte. The sulfate-oxide sludge remaining after separation of the lead metal is treated in a two-step leaching operation with ammonium carhonate, ammonium bisulfite, and waste fluosilicic acid to solubilize the lead for recovery by e1ectrowinning. Prior attempts to e1ectrowln lead have failed because large quantities of insoluble

*MiiCh. Engllleenn:J, (bncordia Univ., M::>ntreal, H3GlM8.)

(9:30 a.m.) "'llIE INFUJENCE OF PARI'ICIES lIND IEFORoIATIoo STIUClURE 00 RECRYSTAIJ..I ZATICliI", D.J. LlOXd, Alean International Limited, Kingston Laboratories, Kingston, Ontano, canada.

Depending on size and volurre fraction, particles can have different effects on the recrystallization of aluminum alloys. At high volurre fractions particles can produce a stable fine grained structure, which is produced by a continuous recrystallization process. At lo.>er volurre fractions coarse particles act as nuclei for recrystallization, the nuclei forming in the strain fields produced at the particles.

70 - TMS-AIME Annual Meeting Program Luge localized strain fields are also produced in alloys which form shear barris during fabrica lion. lEcrystallization can be nucleated in shear bands but if o::Jarse particles are also present nucleation is predominantly associated with these particles. In tl1is paper the microstructural developrents associated with the different effects of particles are examined.

(10:00 a.m.)

MICROSTRUCTURAL CONTROL VIA POWDER METALLURGY I Sponsored by the Solidification and Powder Metallurgy Committees of TMS-AIME Regency Foyer Wednesday, February 27, 1985 Sheraton Centre 8:30 a.m. Session Chairman: I. E. Anderson, Naval Research Laboratory, Washing· ton, DC 20375

"CONTROL OF STRUCTURE DURING HOT ROLLING OF ALUMINUM ALLOYS", T.J. Sheppard, Imperial College, London, England.

The development of structure and sub-structure in the roll gap is described. Results of single and multipass experiments are analyzed to establish the effect of a prior sub-structure. The mechanism of substructural formation is analyzed and variation with processing parameters analyzed. The relationship between structure and properties is established.

(10:30 a.m.) "RECRYSTALLIZATICN aJARACI'ERISTIC3 OF AIllMINUM-l% A/oOlESIUM UNDER HOT v..DRK.nX:; CDNDITlOOS", C.H. Sellars, A.M. Irissarri, E.S. Puchi,

Univ. of Sheffield, Departm2nt of Metallurgy, Sheffield, England. Plane strain c.x:rrpression tests have been carried out using interrupted deformation to determine "restoration index" as a ftmction of holding time be~ defonrations. Spec:irrens have also been quenched and examined metallographically to detennine the oorrelation be~ restoration index and recrystallized. fraction, and to neasure the recrystallized grain sizes. The ranges of oonditions examined were: terrperature 510-350°C, strain in the first defonration 0.15-1.5, strain rate 1.0-3.76 per seoond, initial grain size numbers 54-112 micrcrreters. Fran the results, quanti tati ve relationships describing recrystallization kinetics and recrystalled grain size in tenns of the deforIl'Btion variables are prop::>sed.. These are used. in a ccrrputer program to predict microstructural developrent and rolling loads during typical industrial hot rolling operations. (11 :00 a.m.) GRAIN SIZE AND TEXTURE CONTROL IN HROUGHT ALUMINUM ALLOYS: E. Nes, The Norwegian Institute of Technology, Department of PRySical Metallurgy, Trondheim, Norway. The effect of particles on the recrystall ization behavior of aluminum alloys is qualitatively well understood. Large particles stimulate nucleation of new grains and a fine dispersion of small particles has the opposite effect. A quantitative model for the effect of a bimodal particle size distribution on recrystallized grain size is presented. From the model, recrystallization maps can be derived and such maps are presented for several aluminum alloys. The origin of recrystall ization texture in commercial aluminum alloys is less well understood. The development of the cube texture component during both hot roll ing and after cold roll ing and anneal ing is discussed and the effect of particles on recrystallization texture considered. (11:30 a.m.) "GRAIN REFINEMENT S'lUDlES IN AIl.IMINlIIl-LITHIUM AL.UJYS", C. Gandhi and A.K. Ghosh, lbckwell International, Science Center, Thousand caks, CA 91360. Aluminum-Lithium alloys have excellent applications because of their inherent lightness and high rrodulus. I t is believed that the development of superplastic forming (SPF) potential in these materials will increase range of their application through design advantages gained flUTl SPF. Since fine grain size is oonsidered essential for superplasticity, thenrr::uechanical processing to develop fine grain size in these materials is of oonsiderable interest. In this apper we report the results of thenrarechanical processing of several aluminum-Lithitnn alloys (Al-Li -QJ-M:l-Zr) supplied in various fonns. I t has been found that for effective grain refinerent in these alloys, rrodification of a previously lbckwell developed static recrystallizatioh process produced irrproved results. This rrodified process with an additional stage of oold work after solution trea1:::!rent, produced finer grain sizes than the previous process. The process is further irrproved by oonducting a double processing method which oonsisted of processing the material twice by the static recrystallization process. H~er, these processes did not produce the highest degree of superplasticity. The finest grain sizes in all the alloys studied in this investigation were produced by a strain induced grain refinanent process.

(8:30a.m.) TECHNIQUES FOR THE PRODUCTION OF METAL SIZES OF l(),Jm AND LESS: J.D. Ayers and

POWDER WITH PARTICLE I.E. Anderson, Naval

Research Laboratory, Washington, DC 20375 Particulates of small size are of interest from both scientific and technological points of view because particles with diameters of l~m and less often exhibit structures or properties which are not readily produced in the larger size range typical of most atomizing processes. This paper will briefly discuss some of the diverse processes which have been developed to produce fine powders and will characterize some of the special characteristics of powders produced by these varied processes.

(9:05 a.m.) MI CROSTRUCTURES AND MORPHOLOGI ES OF RAP IDL Y SOLID I F I ED PARTI CULATE: H.L. Fraser, Dept. of Metallurgy and the Materi a 1 s Research Laboratory, Unlv. of Illinois, Urbana, IL. The types of mi crostructure whi ch can be produced by the vari ous techniques of rapid solidification will be reviewed. These inc 1 ude amorphous, mi crocrysta 11 i ne and dendri tic forms. The development of these microstructures in rapidly solidified particulate is described in terms of undercooling prior to nucleation, cooling rate and interface velocity. Examples are given for a series of Al alloys to illustrate the types of metastable phase transformations which can occur, Finally; the ways in which processing variables playa role in effecting given microstructural modifications are outlined. (9:40 a.m.) THE EFFECT OF PARTICLE SIZE ON MICROSTRUCTURAL VARIATIONS OF ATOMIZED Al-8 wt% Fe ALLOY: L. A. Bendersky*, Center for Materials Research, The johns Hopklns UnlVersity, Baltimore, MD 21218, W. J. Boettinger and J. G. Early, Metallurgy Division, National Bureau of Standards, Gaithersburg, MD 20899 Rapidly sol idified Al-8 wt% Fe powder was characterized according to size and microstructure by optical and TEM microscopy. A strong correlation was found between powder particle size and the type of microstructure present for particles in the size range 5 \Ill to 45 \Ill diameter. Four general types of microstructure were observed to be most abundant in the following size fractions: microcellular a-Al « 10 IJlll diameter); microcellular and cellular a-Al « 20 \Ill); fully eutectic a-Al/A16Fe « 30 \Ill); primary intermetallic A13Fe structure (> 30 \Ill). Analysis of these microstructures and the nucleation kinetics of droplets provides a baseline for the estimation of melt undercooling as a function of particle size. The effect of growth kinetics and recalescence on microstructural variation is considered.

*

Guest worker, Metallurgy DiviSion, National Sureau of Standards.

(10:05 a.m.) THE MICROSTRUCTURAL CHARACTERIZATION OF INCONEL alloy MA 6000 POWDER: S.K. Kang. rBM Thomas J. Watson Res. Ctr., P.O. Box 218,

R 6-254, Yorktown Heights, N.Y. 10598. R.C. Benn, Huntington Alloys, Technology Dept., P.O. Box 1958, Huntington, WV 25720. The characterization of mechanically alloyed powders has been investigated in order to understand the mechanical alloying (MA) process as well as provide guidelines for powder quality control. The microstructure of INCONEL alloy MA 6000 powder was revealed by a trartsmission electron microscopy (TEM) investigation, which was the first observation of this kind on a submicron scale. A novel specimen preparation technique was developed in conjunction with the current study. An in-depth characterization of INCONEL alloy MA 6000 powder will be presented in terms of microstructure, phase identification, chemical homogeneity, degree of mechanical working and surface chemistry.

(10:30 a.m.)

Break

(10:40 a.m.) MICROSTRUCTURAL CONTROL OF Sll.ICON-GERMANIUM VIA POWDER PROCESSING S. A. Miiler, General Electric Co. Corporate Research & Development, PO Box 8, Schenectady, NY 1230 I Rapidly solidified silicon-germanium powder was prepared by argon gas atomization and by the gas liquid atomization process using argon, helium and water. The purpose of this work was to determine if the high cooling rates imposed by atomization processes could be used to suppress

TMS-AIME Annual Meeting Program - 71 the large amount of segregation that occurs during conventional solidification of silicon-germanium alloys. Early results indicate that rapid

solidification may actually enhance the apparent degree of segregation which occurs. Conventionally cooled alloy has a heavily cored single phase microstructure. X-ray analysis of the rapidly solidified powder reveals the presence of two phases of different composition. The use of atomization to control the microstructure of the as-atomized powder

and the consolidated alloy in order to produce a more efficient final product will be discussed. (11:05 a.m.) STRUCTURES DEVELOPED DURING RAPID SOLIDIFICATION OF AI-Be ALLOYS: L. E. Tanner, L. A. Jacobson, Lawrence Livermore National Laboratory, Llvermore CA 94550, J. H. Perepezko and B. A. Mueller, University of Wisconsin, Dept. of Met. and Min. Eng., Madison, WI 53706. Rapid solidification structures in AI-Be alloys have been Powders were examined following controlled undercooling. prepared by emulsification_of liquid alloys in a molten salt and the undercool ing behavior was examined by DTA. For AI-rich hypoeutect i c powders wi th sizes be low 44 ~m freez; ng occurred at an undercoo ling of 97°C and ; nvo I ved cata I ys is of the Be phase by primary cellular AI. With hypereutectic alloy powders the formation of primary Be between the liquidus and the eutectic was not suppressed, but still allowed for an undercool ing of up to 76°C below the eutect i c. The powder undercoo 1i ng observat ions have been integrated with supplementary TEM results from rapid quenchi ng methods to account for the domi nance of the Al phase during competitive solidification at high undercooling. The support of the DOE (W-7405-Eng-4S) at LLNL and the ARO (DAAG29SO-K-0068) at UW are gratefully acknowledged. (11:30 a.m.) HEAT FLOW AND SOLIDIFICATION IN METAL POWDER PARTICLES:

ElectromaC)'netically Driven Flows in Molten Woods Metal *A. Murthy, **J. Szekely and N. El-Kaddah, *Alegheny Ludl'.lm Steel Corp., Brackenridge, PA 15014, **Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 Experimental measurements are reported on fluid flow measurements in molten Woods metal where a current is passed between two axy-symrnetrically located electrodes. The actual measurements included data on the velocity fields, on the turbulent kinetic energy and on the turbulent kinetic energy dissipation. The experimental measurements are found to be in good agreement with the predictions.

(9:45 a.m.) A PLUME MODEL FOR GAS, POWDER AND WIRE INJECTION INTO LIQUID METALS:* L.R. Farias, and G.A. Irons, McMaster University, Hamilton, Ontario, Canada --------Previous models for the two-phase plumes in gas-stirred vessels have assumed constant temperature, pressure, void fraction and essentially equal and constant gas and liquid velocities as the bubbles rise. In the present model, one-dimensional, steady state, two and three phase equations of continuity, momentum transfer and heat transfer are solved for a variety of conditions relevant to Ladle Metallurgy. In water, the gas and liquid velocities were substantially constant during rise, and in qood agreement with publ i shed experimental data, however in I i qui d metals the gas and 1 iquid velocities increase continuously during rise due to the decreased head of 1 iquid. For powder injection with and without gas to simulate lance injection and wire feeding of solids, the plume velocities were calculated. At high solids loading heat transfer problems can cause local freezing of the bath and slow heating of the particles.

S.D.

Ridder, National Bureau of Standards, Washington, DC 2023Taiid C.G. Levi, University of California, Santa Barbara, CA 93106 The microstructure of metal powder particles will be co-related to proposed solidification history using recently developed models of heat flow, nucleation, and interface stability during rapid solidification. Particular emphasis will be placed on interface morphology, recalescence, and solute partitioning. Limits to partitionless solidification will be addressed as well as alloy selection to achieve homogenous solidification microstructure.

MODELING IN PROCESS METALLURGY III: METALLURGICAL PROCESSES Sponsored by the TMS Physical Chemistry Committee and the PTDlISS Wednesday, February 27, 1985 8:30 a.m.

(9:20 a.m.)

Dominion A Sheraton Centre

Session Chairmen: G. Irons, McMaster U., Hamilton, Ontario, Canada L8S 4L7; R. Mutharasan, Dept. of Chemical Engr., Drexel U., Philadelphia, PA 19104

(8:30 a.m.) Pulsating Flows in Metals Processing Operations, J. Szekely, T. Kang and J. Woo, Department of Materials Science and Engineering I Massachusetts Institute of Technology, Cambridge, MA 02139

Experimental measurements are reported on the_ flow patterns and turbulence characteristic of model systems, which are agitated using a pulsating flow field. Two types of systems are discussed, one a gas bubble agitated water model and the other an electromagnetically driven circulation system. The experimental measurements are compared with theoretical predictions.

(8: 55 a.m.) PHYSICAL REFINING OF STEEL MELTS USING OPEN PORE CERAMIC FILTERS:

S. Ali, R. Mutharasan and D. Apelian, College of Engineering, Drexel University, Phila., PA 19104 Steels containing alumina inclusions have been successfully filtered using monopore 20 ppi and multipore 30/40 ppi open pore ceramic filters. Experiments were carried out to detennine the filtration efficiency of these open pore ceramic foam filters for steel applications. Effect of melt velocity, filter length and filter geometry were examined. Results show "short time" filter efficiencies as high as 97%; it has been observed that the inclusions are attached to the filter along its length. Metallographic analysis of the spent filters indicate that interception is the dominant mechanism of inclusion entrapment.

(10:10 a.m.)

3reak

(10:20 a.m.) BEHAVIOR OF LIQUID INCLUSIONS IN PACKED BEDS - A MODEL STUDY:

D. Apelian, R. Mutharasan, S. Luk and V. Handa; College of Engineering, Drexel University t Philadelphia, PA. The entrapment and migration of liquid phase inclusions in filters used for physical refining of melts is not w~ll understood. Flow visualization studies of a low temperature model system consisting of a continuous phase and a dispersed liquid phase (inclusions) provide an experimental tool for observing entrapment, saturation and release phenorr.ena visually. Based on these results, a physical model can be formulated. For quantitative comparison, the low temperature model system is based on fundamental dimensionless parameters such as the Weber No., Capillary No. and Reynolds No. The presentation will also include flow mapping of the two phase flow in packed beds.

(10:45 a.m.) RADIAL SEGREGATION OF GRANULAR SOLIDS IN HORI ZONTAL ROTARY REACTORS: N. Nit anand and H. Henein, Carnegie-Mellon University, Pittsburgh, Pa. 5213

1

Rotary reactors such as ball mills, driers, mixers, blenders and kilns are extensively used in chemical and metallurgical industries to process billions of tons of granular solids. Longitudinal and radial segregation due to size, shape and density differences of the feed or product are often encOtmtered in these unit operations. In this paper, the mechanisms of radial segregation due to size differences will be reviewed. The kinetics of radial segregation are observed and quantified using high speed movies. Both the mechanism and kinetics of radial segregation are affected by the material, design and operating variables. The scale-up of the segregation process is investigated using two cylinders, 0.2mID x 0.2mL and 0.4mID x 0.4mL. The size, shape, composition and location of the segregation core will also be discussed. (11 :10 a.m.)

EXAMINATION OF GAS INJECTION BY AN ULTRASONIC TECHNIQUE: L. Matikainen, G.A. Irons, McMaster University, Hamilton, Canada The kinetics of bottom blown conventers are poorly understood because of the 1ack of suitable transducers. "program at MtMaster has been directed at non-intrusive methods of examining gas/metal interfaces in iron and steel melts. An ultrasonic system, consisting of a sensor capable of sustained operation in iron-steel melts, an ultrasonic analyzer, a transient memory and data logger has been designed and constructed. The high speed data analysis and logging electronics allows the capture of a success i on of signals to yi e 1d the pos it i on of the ga s/meta 1 interface as a function of time. By examining the gas/metal interface, the frequency of bubbling and the size of the bubbles may be determined independently of the gas flowrate. Results show good agreement with derived bubble volumes of other workers using different techniques. However, the measured bubble radii are considerably smaller than those expected using a spherical bubble. A description of the apparatus, brief theoretical basis and results of experiments with gas/water, gas/mercury and gas/ironsteel systems will be presented.

72 - TMS-AIME Annual Meeting Program (11:35 a.m.)

(10:45 a.m.)

MTHEftATlCAL MODELING OF MINOR ELEMENT BEHAVIOR IN A FLASH SMELT-

LOW TEMPERATURE GRAIN-BOUNDARY DIFFUSION MECHANISMS IN NOBLE METAL ALLOYS, D• .B •.. ButrY!llQwiCL and J. W. Cahn, National Bureau of Standards, Ga ithersburg, Maryl and

ING FURNACE: p.e. Chaubal and H.Y. Sohn, Department of Metallurgy and Metallurgical Engineering, University of Utah, Salt Lake City, VT 84112, and L.K. Bailey, Kennecott-Process Technology, 1515 Mineral Square, Salt Lake City, VT 84112 A mathematical model has been developed to study the distribution behavior of minor elements in a flash smelting furnace. The model has been formulated based on both kinetic and thermodynamic considerations. The volatilization of minor elements is considered to be mass transport controlled, the driving force being the equilibrium partial pressure of various minor element species. Thermo-

dynamic equilibrium considerations in conjunction with mechanical suspension determine the distribution between various phases in the molten bath. The model has been used to study the effect of oxygen enrichment in the process air and the final mat te grade produced under commercially acceptable maximum particle temperatures. In this paper the distribution behavior of the four minor elements - As, Sb, Bi and Pb is reported.

PHASE DIAGRAMS, ALLOY PHASE STABILITY AND THERMODYNAMIC ASPECTS OF NOBLE METAL ALLOYS V: Selected Experimental Approaches Co-sponsored by TMS Committee on Alloy Phases, ASM Alloy Phase Diagram Data Committee and ASM-MSD Thermodynamics Committee Wednesday, February 27, 1985 8:30 a.m.

Versailles Terrace Sheraton Centre

Session Chairman: T. B. Massalski, Department of Metallurgical Engineering and Materials Science, Carnegie-Mellon University, Pittsburgh,

PA 15213

(8:30 a.m.) FERMI SURFACE STUDIES OF DISORDERED ALLOYS BY POSITRON ANNIHILATION EXPERIMENTS:* Stephan Berko, Brandeis University, Waltham, MA 02254.

Positron annihilation experiments are able to provide a measure of the Fermi surface of high concentration disordered alloys where more standard solid state techniques fail. The angular correlation of annihilation radiation (ACAR) from positrons introduced in an oriented crystal gives the momentum density of electrons sampled by the thermalized positron; discontinuities in the ACAR data reflect the size and shape of the Fermi surface. New IIIJlt1-detector techniques provide two-dimensional (2D) ACAR surface. used to reconstruct the 3D topology of the Fermi surface. After a general introduction to the theory of ·the ACAR experiments, the application of this technique to the study of substitutionally disordered noble metal alloys will be reviewed.

·Work supported by NSF Grant DMR-7926035.

(9: 15 a.m.) GRAIN BOUNDARY STRUCTURE IN THE NOBLE METALS: S.L. sas, Materials Science and Engineering, Cornell Univers1ty,fhaca, NY 14853. Electron microscopy, electron diffraction and X-ray diffraction techniques (including synchrotron radiation) have been used extensively to study the structure of tllt and twist grain boundaries in the noble metals. The results of these studies w1l1 be rev i ewed. It w1l1 be shown that di ffract i on techn i ques can provide detalled information on the atomic structure of large angle boundaries, in particular giving the projected atomic structure and the magnitude of the expansion normal to [OOIJ twist boundaries in Au. Diffraction studies have shown that the structures of the same [OOIJ twist boundary in Au, Ag and Cu are quite simllar. Generalizations about the structure of grain boundaries on the noble metals w1l1 be made based on these resu 1 ts. (10:00 a.m.)

Diffusion-induced grain-boundary motion not only leads to unexpectedly 1arge atom transport at low temperature, but also in significant microstructural changes. In noble metal alloys it has been observed in di ffus i on couples, and as a factor in cellular precipitation and in oxidation and corrosion.

PHASE TRANSFORMATIONS II TMS-AIME General Abstract Session Wednesday, February 27, 1985 8:30 a.m.

Jefferson Suite Sheraton City Squire

Session Chairman: T. B. Lindemer, Chemical Technology Division, Oak Ridge National Laboratory, P.O. Box X, Oak Ridge, TN 37831

(8:30 p.m.) INFLUENCE OF NUCLEATION AND CRYSTALLIZATION HEAT TREATMENTS ON CRYSTAL FORMATION IN GLASSES MADE FROM METALLURGICAL SLAG: R.N. Andrews, M.R. Fletcher, University of Alabama in Birmingham, Department of Materials Engineering, Birmingham, AL. The influence of various nucleation and crystallization heat treatments on the type and amount of crystal formation in glasses made from Cupala slag was studied. Nucleation and crystallization temperatures were determined using DTA analyses of the glasses. The onset of crystal formation was monitored using both x-ray diffraction and optical tnicrosc.opy techniques. Single and conventional two step heat treatments were utilized and the effectiveness of prior nucleation tre.atments on the final microstructure was determined. Results indicated that the extent of crystallization as well as the crystal morphology was a function of both the heat treating temperatures and times utilized. Crystallization also appeared to be enhanced in these slag glasses in the presence of a liquid at higher temperatures.

(8:50 a.m.) THE INITIAL STAGES OF DISCONTINUOUS PRECIPITATION IN AL-ZN ALLOYS:

I.G. Solorzano, DCMM-PUC/RJ, Rio de Janeiro, 22452 Brazil and G.R. Purdy, McMaster Dniv., Hamilton, ant. L85 4L7, Canada The isothermal decomposition in AI-22 and 28 at % Zn supersaturated solid solutions is rapidely dominated by a discontinuous mode of precipitation. The resultant lamellar structure is remarkable regular, the initial stages of fonnation not being easely detectable. In some cases, precursor grain boundary displacements pinned by equilibrium preciptates have been observed. A lesssupersatured solid solution, Al-12 at % Zn, subjected to the same isothermal treatment has revealed an effective grain boundary migration without discontinuous precipitation. Analytical electron microscopy studies. conducted in all cases t have shown that the region swept by the migrating boundary is solute depleated to a concentration close to the equilibrium. In the absence of ca~ pillary or precipitate traction forces the role of a chemical force is discussed. It is suggested that in thio system the steady state discontinuous preoipitation process is preceded by a diffusion induced grain boundary migration event,

(9 :10 a.m.)

FUNDAMENTAL STl1DIES ON THE PEARLITE REACTION IN A HYPOEUTECTOID STEEL: S.W. Thompson and P.R. Howell, Department of Materials Science and Engineering, Penn State Univ., Univenity Park, PA Transmission electron microscopy has been employed to study the pearlite reaction in a 1.5% Mn, 0.3% 51, 0.15% C steel. In particular, the initiation of the pearlite reaotion and the crystallographic relationships between ferriee and oementite have been investigated. I t is generally accepted that the pearlite reaction is initiated by the Smith/Hillert mechaniam of branching. Although this meohanism has been found to be active in the alloy investigated, a further mode of initiation has been found, which is analogous to the Tu and Turnbull mechanlom for discontinuous precipitation. The crystallography of the pearlite reaction has been studied using low camera length convergent beam electron diffraction patterns. This method yields results which are accurste to better than 1'.

THERMOELASTIC MARTENSITIC TRANSFORMATIONS AND THE SHAPE MEMORY EFFECT: C. M. Wayman, Department of Metallurgioal and Mining Engineering and the Materials Researoh Laboratory, University of Illinois, Urbana IL 61801

This research was supported by The Atlantic Richfield Foundation

Reoent studies of thermoelastio martensites and the assooiated shape memory effeot indioate the importanoe of martensitio transformations in Cu-based and other nonferrous alloys. Some of this work will be desoribed, and it will be shown that the various memory alloys have oommon orystallographio oharaoteristios and undergo similar deformation and shape memory prooesses. Some applioations of the shape memory effeot will be presented.

THE ROLE OF SHEAR IN THE HETEROGENEOUS NUCLEATION OF e' IN Al-Cu:· U. Dahmen, M. Wall and K.H. Westmacott, Materials and Molecular Research Division, Lawrence Berkeley Laboratory, University of Cal ifornia, Berkeley, CA., 94720.

A oolor film showing martensi te deformation and shape reoovery meohanisms will be shown.

(9:30 a.m.)

Using the process of repeated preCipitation of e' on cl imbing dislocation loops in Al-4Cu, a contrast analysis by transmission electron microscopy shows that by dissociating into a/2 <100> partials the dislocation can accommodate not only the strain

TMS-AIME Annual Meeting Program - 73 field but also the crystal structure of the growing precipitate. The experimenta 1 evi dence is shown to be cons is tent wi th a recent structural model emphasizing the crucial role of the shear component of the transformation strain in the formation of e' precipitates. Accommodation of this shear component can exp 1 a i n the preference for 1edges two uni t cells hi gh duri ng . ~'T , owth s work , s supported by the Di rector, Offi ce of Energy Research, Office of Basic Energy Sciences, Materials Sciences Di vi s i on of the U. S. Depa rtment of Energy under Contract No. DE-AC03-76SF00098.

r

cementite and the pearlite of the copper-containing steel. Copper also decreaaed the growth rates and increased the interlamellar spacings of isothermally formed pearlite. *This work was supported by the Director. Office of Energy Research. Materials Sciences Division of the U.S. Department of

Energy under Contract No. DE-AC03-76SFO0098.

(11 :10 a.m.) COMPARISON OF THE COARSENING KINETICS OF THE DISPERSED PHASES IN AI.Fe, A1·Fe·Mo·V and Al'Fe'Ce RSP P/M ALLOYS:* L. Angers, J. L.

(9:50 a.m.)

Horng, M. E. Fine and J. R. Weertman, Dept. of Mat. Sci. & Eng. and Mat. Res. Ctr., Northwestern University, Evanston, lL 60201

OSTWALD RIPENING OF RARE EARTH DISPERSOIDS IN RAPIDLY SOLIDIFIED C>-Ti ALLOYS." Y.Z. Lu and S.H. Whang, Barnett Insitute, Northeastern University, Boston MA 02115.

The stability and morphology of the dispersed phases in 4 RSP P/M Al alloys (Al·8Fe, AI.lOFe.1.5Mo·1V, Al·8.8Fe·3.7Ce and A1·8.9Fe·

Rapidly sol idif ied ternary Ti alloys contai ni ng rare earth metals (Y, La, Er, etc.) reportedly show excellent mechanical properties at both room and high temperatures resulting from stable dispersoids. These rare earth dispersoids are known to take both oxide and non-oxide forms depending upon alloying elements, as well as oxygen availability. Until now, little was known about the kinetic aspects of the particle coarsening of these dispersoids. Recently, a systematic study of particle coarsening has been conducted by the authors at the temperature range of 700 0 - 900"c in Ti-Sn-Y (La, Er) alloy systems. The mechanical properties of these alloys have been studied using a mlcrohardness tester. In this paper. we are presenting overall results including diffusion coeffiCient, activation energy and structural identities of the dispersoids.

cold work.

I

"Research sponsored by the Off ice of Naval Research.

6.9Ce 1n wt.%) are under investigation as a function of exposure to elevated temperatures (316, 375, 425°C) with and without prior

While all alloys exhibit coarsening kinetics much

faster than predicted by diffusion control, there is considerable variation 1n the coarsening rates of particles in the various alloys. Coarsening rates in the AI-Fe and Al·FeoCe alloys are

similar at 375 and 4250 but the Al·Fe·Ce alloys appear much more stable at 3160 C.

*

Supported by the Air Force Office of Scientific Research

through Grant No. AFOSR-82-0005B. (11 :30 a.m.) ORDERING AND AGING REACTIONS IN AN Au-Cu-Pt-Ag ALLOY, M. M. Karnowsky, A. D. Romig, Jr. and F. G. Yost, Sandia National Laboratories, Albuquerque, NM 87185

Ordering in a 53-33-7-5 at% Au, Cu, Pt, Ag alloy has been studied by electrical resistivity, optical metallography, XRD and AEM from 350 to 575°C. The objective was to compare the kinetics and

(10:10 a.m.)

thermodynamics of ordering in the Au-Cu-Pt-Ag alloy to those in the CuAu stoichiometric alloy. The quaternary alloy is disordered

DISCONTINUOUS COARSENING OF THE LAMELLAR PRODUCT OF THE EUTECTOID REACTION IN A ZN-40.5 AT. PCT. AL ALLOY:" G. Sarkar, Materials Engineering Dept., Rensselaer Polytechnic Institute. Troy, NY and R.A. Fournelle, Dept. of Mechanical Engineering, Marquette University, Milwaukee, WI

FCC (a • .393 run) above T. 'V 605 'C. Below T. a CuAu I analog (L10, a = .402 nm, b = .373 nm) fonns. The Pt and Ag substitute for the Cu in the original lattice. AEM X-ray microanalysis showed that Pt partitioned to the CuAu I type precipitate while Ag partitioned to the disordered matrix. Pt and Ag eliminated

The morphology and growth kinetics of the lamellar eutectoid reaction as well as the discontinuous coarsening of the lamellar eutectoi d have been s tudi ed by 1i ght and electron mi eros copy and x-ray diffraction. The eutectoid transformation was studied between 1570 and 254 0 C while the coarsening reaction was studied between 131 0 and 254 0 C. The coarsening reaction was observed to decompose the lamellar structure of the eutectoid at all aging temperatures. Analysis of the growth rates, lamellar spacings and phase compositions for both reactions according to existing theories shows them to be controlled by grain boundary diffusion in the reaction front. '*rhis work was supported in part by National Science Foundation Grant No. DMR-7915218.

the CuAu II in the temperature range studied. The kinetics of ordering can be fitted to a modified form of the claSSical NowickWeisberg equation. The activation energy for ordering is '\, 24 kcal/mole. which is similar to the Q for stoichiometric CuAu I

and the Q for interdiffusion in CuAu alloys. *This work performed at Sandia National Laboratories supported by

the U.S. Department of Energy, Contract No. DE-AC04-7DP00789.

PHYSICAL METALLURGY OF HIGH TEMPERA· TURE ALLOYS Sponsored by the TMS-AIME High Temperature Alloys Committee Wednesday, February 27, 19815 8:30 a.m.

Province Suite Sheraton Centre

(10:30 a.m.) STEREOLOGICAL ANALYSIS OF AN AL-3%Cu-2%Li-O, 12Ur ALLOY, M,H, TOltln~, A,K. VAludavan+ and P.R, Howall~, "Department of Materials Sciance and Engineering, Penn State Univ., Univenity Park, PA, +Alcoa Laboratori.. , Alcoa Centor, PA

Session Chairmen: Ronald C. Gebeau, Carpenter Technology Corp .. P,O. Box 662, Reading, PA 19603j P. K. Wright, General Electric Co., Matis. Technology Laboratory (M87), Evendale, Ohio 45215

Standard ataraololical technique., al applied to 'rEM, have baan amployed to analy .. precipitate d1atribut1on in an Al-3%Cu-2% Li-0,12Ur alloy which had baen aged at 190'C for times in the range 1. 25 to 520 hOUri. In the ay.tem analyzed, the precipitate pha... encountered were 6, 6', T I' Al~zr and e', The variou. phases have been analyzad in term. of, (i) volume fraction; (11) upect ratio for the plate shaped precipitatea (T , e'); (i11) 110e diatribution; (iv) competitive coanening rtactions. The data from these studies indicate that dissolution of 6' and e' occun after extended sgeing times and that tha major matrix phase is T I' while the dominant species on grain boundaries is 6. Results concerning the variation in the mean aspect ratio of the T I phase as a function of time, will be reported.

(8:30 a,m,)

This research was supported by a Grant-in-Aid from the Alloy Technology Division, Alcoa.

(10:50 a.m.) PRECIPITATION OF PROEUTECTOID CEMENTITE AND PEARLITE IN A Fe-I.3 wt.% C-3.5 wt.% Cu STEEL· .LA.. HaUDszuk, R.M. Filher and G. Thoma .. Dept. of Materialo Science. Univ. of Ca liforni .. and Lawrence Berkeley Laboratory. Berkeley. CA 94720 The tranlformation kinetic. and microltructure of hothermally reacted Fe-I.3wt.%C-3.5wt.%Cu have been examined and compared to those of a binary Fe-C alloy of comparable carbon carbon content. The T.T.T. diagram a geDerated for thOle alloya showed that the curves reprelenting the .tart of the proeutectoid cementite tranlformation Were lubatantially the lame for both ateela but that the Itart of the pearlite traDsformation was sigDificantly retarded by copper. Transmiaaion electron microlcopy revealed the

existence of fine scale precipitates within the proeutectoid

TEMPERATURE DEPENDENCE OF v-v' LATTICE MISMATCH IN NICKEL-BASE SUPERALLOYS, M, V. Nathal, R. A, MacKay, and R. G. Garlick, NASA Lewis Research Center, Cleveland, Oh10 44135. The purpose of this study was to determine the v-V' lattice mismatch of several nickel-base superalloys as a function of temperature, X-ray diffraction was used to measure the y and v' lattice parameters of or1ented single crystal slices at temperatures ranging from 25 to 1l000C. The alloys in this investigation included the commercial alloy NASAIR 100 and some of its derivatives, as well as a model Ni-Al-Mo·Ta alloy. The results indicated that the temperature dependence of the lattice mismatch varied substantially for the different alloys, and the mismatch measurements obtained at ambient temperature did not always reflect the elevated temperature measurements. The influence of elevated temperature m1smatch on the kinetics of direct10nal coarsening of the v' preCipitate was also examined. (8:55 a.m.) THE ROLE OF MOLYBDENUti IN NICKEL-BASE SUPERALLOYS*: Paul W. Keefe, John P. Collier and John K. Tien, Center for Strategic Materials, Renry krumb School of Mines, Columbia University, New York, N.Y. 10027, Three c01111lercially available nickel-base superalloys, Udimet 710, B-1900 and Inconel 738, were studied to determine the effect on alloy properties of an atom for atom substitution of Mo for the refractory elements Ta, Nb and W. Properties of the modified alloys were compared wi th those of the standard alloy compos i t ion by a series of mechanical tests (tensile, creep/stress rupture and elevated temperature low cycle fatigue). In addition, chemical

74 - TMS-AIME Annual Meeting Program analysis to determine the relative amounts and compositions of the y, and y' and carbide phases and the lattice mismatch were done. Differential thennal analysis, oxidation kinetics and molten salt corros i on res i stances a re also reported. *This work is sponsored by the U.S. Office of Naval Research under the monitorship of Dr. Don Polk.

(9:20 a.m.) BORIDE CONSIDERATIONS IN DESIGN OF NICKEL-BASE SUPERALLOYS: G.E. Maurer, J.A. Domingue, F.A. Schweizer,Special Metals, New Hartford, NY & J.F.Radavich, Micromet Laboratory, West Lafayette,IN Boron has ach i eved popu 1 ar ity as an add it i ve to improve castab ility and workability and as a carbon SUbstitute. A generic study of Dorides, with emphasis on boride formers - Cr, Nb, Mo and W was performed with minimal interference from carbides and nongamma prime phases. Alloys studied were lean in certain elements to avoid phase instability. Eight simple permutations of Nb, Mo and W were studied under constraint that, except for a control alloy with none of these elements, their total atomic percent was constant. Differential thermal analysis was used to measure incipient melting temperatures and relative amounts of boriderich eutectics. Phase extraction and x-ray diffraction of res idues were performed on as-cast samples and on samples aged at 843'C to promote M23(C,B)6 formation. Results are applicable to understanding complex phase relationships of commercial boronbearing alloys and predicting boride structures in alloy design programs, and suggest the need for continued investigation into the role of boron in superalloys at lower carbon levels.

(11 :10 a.m.) au!IIICAL AND snucrol!AL IXIJlPATlBILITJ IN TIT' - CI IXIJIPOSITES I!.L. l.uW!! a ..d A.II. Ritter Ge ..eral Electric CoIlpa..,. Corporate Relearch lad D.velo~... t P.O. Boz 8. Sch .... ctldy. N.w York 12309 Sch .... ctady, Now York 12345

Lly.r.d lad l . . i ..ltod Itncture. ot Tlr' (Ni, AI. 110, B) oad CI (1'0) have been produced. by low prellure plal.a depoli tion. Interfacial reali.naeDt caD OCC11%' durinl the in litu themal e.z.polur. i ... d1oto1y tollowin, d,poliUo... Difhoio .. botw .... tho Iplotl of rlr' powd.r oad CI 110 powdor occurs to OItablhh ch . . icol .quilibriaa. Thele Itructural chaDC •• have been Itudied by trln_illion .lectro .. microlcopy. Th. pouibility of limit.d r .... lUIl' of pr.vioudy lolidified rlr' Iplata due to tho very hi,h t ... porltur .. ot Irrivin, liquid 110 dropleta will b • •voluot.d. Sublequent thermal treatmentl Cln further .1 ter the ch_ical equilibri-.. and microltructural Itability. The influence of Itr'll i.poled It t_porotur. 0 .. tho intorfacial Itlbility will 1100 b. disculsed.

SOLIDIFICATION I TMS-AIME General Abstract Session Wednesday, February 27, 1985 8:30 a.m.

Washington Suite Sheraton City Squire

Session Chairman: R. J. Schaefer, Metallurgy Division, Materials Alb3, National Bureau of Standards, Gaithersburg, MD 20899

(9:45 a.m.) (8:30 a.m.) THE RESPONSE OF COBALT-FREE UDH1ET 700 TYPE ALLOY TO t10DIFIED HEAT TREATMENTS: Fredric H. Harf, NASA Lewis Research Center, Cleveland, OH 44~--Strategic materials conservation calls for reducing the consumption of cobalt in superalloys. A study was therefore conducted to replace cobalt in Udimet 700 by nickel. In the cobalt free alloy the rupture and creep properties were inferior to those of the standard all oy with 17% cobalt, when both were gi ven substantially equal heat treatments, suitable for turbine disks. These heat treatments compri sed a pa rt i a 1 so 1 uti oni ng of the gamma prime phase followed by a four step aging treatment in which the gamma prime dissolved in the gamma matrix was precipitated as fine and ultrafine particles. By adjusting some of the aging temperatures it was possible to improve the rupture lives and creep rates. This effect was greatest in the cast and wrought alloy and significant in hot isostatically pressed materi a 1 produced by powder metall urgy. Exami nati ons showed that the improvement in properti es was associ ated with intentionally increased proportions of ultrafine gamma prime particles in the microstructure.

DIRECT OBSERVATION OF COARSENING SECOND PHASE DOMAINS: P. W. Voorhees and R. J. Schaefer, Metallurgy Division, National Bureau of Standards, Ga i thersburg, MD 20899 Recent theoretical work has predicted that coarsening particles should interact diffusionally at finite volume fractions of coarsening phase, thus violating an important assumption upon which the classic Lifshitz-Slyozov-Wagner theory is based. In an effort to prove the existence of these diffusional interactions, experiments were performed using a succinonitrile - 0.1 m/o acetone alloy which permitted direct observation of coarsening liquid droplets in a solid matrix. The experiments showed that diffusional interactions are quite strong, even at low ( 3%) volume fractions of liquid. Besides influencing the coarsening rates of individual droplets, these diffusional interactions also induced droplet movement within the sol id. The possibility of droplet migration is consistent with an analysis of the diffusion problem between two coarsening spherical particles of arbitrary size in the quasi-stationary approximation. The experimental results along with the theoretical analysis will be presented.

(8: 50 a.m.) (10: 10 a.m.)

Break

DIRECT THERMAL MEASUREMENT OF ADIABATIC DENDRITIC COARSENING:* M.E. Glicksman and N.B. Singh, Materials Engineering Department, Rensselaer Polytechnic Institute, Troy, NY.

(10:20 a.m.) THE

DEVELOPMENT

OF

CMSX- 5,

A THIRD

GENERATION,

HIGH

STRENGTH

SINGLE CRYSTAL SUPERALLOY: G.L. Erickson, K. Harris, R.E. Schwer; Cannon-Muskegon Corporation, P.O. Box 506, Muskegon, ~!ichigdn,

49443, U,S.A.

CMSX-5 is a single crystal cast superalloy. designed to be a lower cost, Re free, high strength turbine blade ma.terial. The alloy development is reviewed in detail, specifically examining single crystal castability, heat treatment solutioning response, stress- and creep-rupture capability, elevated temperature phase stability plus limited environmental testing results.

We have shown that the average temperature of a rapidly recalesced and adiabatically constrained solid-liquid mixture tracks the process of dendritic coarsening. Such microstructural ripening processes result in an asymptotic approach toward the bulk thermodynamic melting point, with the mean Gibbs-Thomson off-set, , decaying eventually as Bt- l / 3 , where t is the time since nucleation, and B is the coarsening rate constant. These experiments also provide data. which directly yield the solidliquid interfacial energy. Recent results obtained for rapidly solidified ice/water and succinonitrile are in agreement with earlier interfacial energy measurements based on the gradientgroove techni que. Extens i on of the new method of meta 11 i c systems wi 11 be di scussed.

(10:45 a.m.)

*The authors gratefully acknowledge the support provided by the Division of Materials Research, National Science Foundation, Washi ngton, D. C. under grant DMR-8308052.

FIBER/MATRIX COMPATIBILITY IN TFRS*: R.S. Bellows, T. Caulfield and J.K. Tien, Center for Strategic Materials, Henry Krumb School of Mines, Columbia University, New York, N.Y. 10027.

(9:10 a.m.)

The compat i bi 1 ity of tungsten fi bers with both an I nco loy 903 (nickel base) and a FeCrA1Y (iron-chromium base) matrix in Tungsten Fiber Reinforced Superalloy (TFRS) composites were studied after annealing in the temperature range 1000-1200C for 100 plus hours. I nterdi ffus i ona 1 effects and the k i net i cs of interface mot i on were examined by optical and quantitative analysis. It was found that after anneal i ng, both TFRS compos i tes fonned react i on zones around the remaining fiber. The compositions of the reaction zone and the local reaction zone/matrix equil ibrium were determined by SEMEDS analysis for both systems. The chemistries in these reaction zones were not only constant, suggesting a compound phase, but further more, corresponded to a ~-type phase ((CoNiFe)7 (WCr)6)' In addition to fiber recrystall ization at higher temperatures for both matrices, recrystallization was also observed in the Incoloy 903 matrix adjacent to the fibers at higher temperatures. *This work is sponsored by NASA-Lewis Research Center by grant NASA NAG-3-410 under the jot nt monitorship of Donald Petrasek and Robert Signorell i.

STEM ANALYSIS OF LASER PROCESSED AUSTENITIC STAINLESS STEELS CONTAINING UP TO 9% MOLYBDENUM: P.G. Moore and C.S. Pande, Naval Research Laboratory, Washington, DC 20375 and S. Smith,

Geo-Centers, Inc., Camp Springs, MD 20023 The metallurgical structures that result from laser melting and laser alloying of 304 stainless steel have been investigated. The rapid heating and rapid cooling result in highly textured surface layers with a fine dendritic solidification structure. Because the average dendrite spacing is less than 500 run, the metallurgical structure can only be resolved by the use of TEM and STEM analysiS. Ibe dendrite spacing has been used to estimate cooling rates in excess of a million degrees per second during solidification. TIle misorientation across dendrite boundaries have been measured using selected area diffraction and microdiffraction techniques. The structures of the dendrites and the interdendrit1c regions reflect the extremely high temperature gradients experienced during solidification. Variations of chemical composition across dendrite boundaries a re being measured using STEtrEDS techniques.

TMS-AIME Annual Meeting Program - 7S (9:30 a.m.) CELLULAR MICROSEGREGATION IN RAPIDLY SOLIDIFIED Ag-15 wt% ALLOYS: L. A. Bendersky* Center for Materials Research, The Johns Hopkins University, Baltimore, MD and W. J. Boettinger, Metallurgy Division, National Bureau of Standards, Gaithersburg, MD Mi cros tructura 1 and mi crochemi ca 1 analys is has been performed on Ag-15 wt% Cu ailoys produced by electron beam melting with solid ification velocities of 2.5,12 and 18 cm/s. Cellular structures of the Ag-rich phase are produced with spacings of 0.8, 0.3 and 0.2 lI11, respectively. Intercellular regions contained fine eutectic at the lowest speed but only Cu-rich phase at the higher speeds. The composition within the cells was found to be nearly uniform and 12.5 ± 1 wt% Cu. The uniformity and level of the Cu content within the cells are discussed. *Guest worker, Metallurgy Division, National Bureau of Standards, Gaithersburg, MD The authors acknowl edge the support of DARPA.

(9:50 a.m.) RAPIDLY SOLIDIFIED MICROSTRUCTURES OF PIM ALUMINUM ALLOY AI-6Fe-6Ni: Young-Won Kim, Metcut-Materials Research Group, P.O. Box 33511, wroght-Patterson AFB, OH 45433; W. M. Griffith and F. H. Froes, Air Force Wright Aeronautical Laboratories, Materials Laboratory, AFWALIMLLS, WrightPatterson AFB, OH 45433 AI-(4-8) wt % Fe-(4-B) wt % Ni is one of several emerging PIM aluminum alloy systems that are dispersion hardened by thermally stable intermetallic compounds and thus have potential for elevated temperature applications. The alloys of this system are prepared from atomized powders that are subsequently consolidated and processed. These alloys are known to be characterized typically by eutectic structure consisting of rod-type intermetallic compounds. In this study, AI-6Fe-6Ni was investigated to characterize microstructure and its thermal response. A coupled-eutectic struc;.ture was generally observed in relatively slowly cooled «1 OSoCs 1) powders and quasi-pl~nar solidification was observed in powders cooled faster (>10 So Cs 1). This will be 'explained using a non-equilibrium phase diagram. Spheroidization of intermetallic eutectic rods that precedes coarsening above 400°C will be discussed.

(10:10 a.m.) COMPARISON OF MICROSTRUCTURES AND PROPERTIES OF SEVERAL RAPIDLY SOLIDIF~ED ALUMINUM-RAj}E EARTH ALLOYS: a S. J. S.vage a , Y. R. Mahajan J A. G. Jackson J and F. H. Froes

a Air Force Wright Aeronautical Laboratories J Materials Laboratory, AFWAL/MLLS, Wright-Patterson AFB, OH 45433 bsystems Research Laboratories J Inc., 2800 Indian Ripple Road J Dayton, OH 45440 A series of rapidly solidified aluminum-rare earth metal binary alloys have been prepared by pendant drop melt extraction. Characterization of the ribbons thus produced, by optical. TEM. STEl1. X-ray diffraction. and microprobe analysis reveals extended solid solutions and at least one new metastable phase. A wide range of microstructures are seen, including "conventionalll RS type zones. a cellular structure surrounded by a degenerate eutectic, and coupled (lamellar) eutectic solidification. A bimodal precipitate distribution is seen in many areas of the ribbons (in two alloy systems) consisting of an intergranular precipitate 20-50nm diameter, with qccasional larger (0.1-0.5~m) precipitates in a solute denuded zone at the gra'in boundaries. A series of isothermal and isochronal heat treatments conducted to determine the thermal stability of these microstructures indicate a wide variation in the temperature at which peak hardness is attained in the different alloy systems. In an aluminumgadolinium alloy a fine (20nm) precipitate resists coarsening for 1 hour to at least 400°C.

STEPHEN R. SHATYNSKI MEMORIAL SYMPOSIUM ON SURFACES AND INTERFACES-I Sponsored by ASM -MSD Thermodynamics Committee Wednesday, February 27, 1985 8:30 a.m.

Consulate Suite Sheraton Centre

Session Chairmen: Peter J. Meschter, McDonnell Douglas Corp., P.O. Box 516, St. Louis, MO 63166; Randall M. German, Materials Engineering Dept., Rensselaer Polytechnic lnst .• Troy, NY 12181

(8:30 a.m.) Introductory Remarks:

P. J. Meschter

(8:35 a.m.) MEMORIAL: M. E. Glicksman, Chairman, Materials Engineerin, Department, Rensselaer PolytechniC Institute, Troy, NY 12181 (8:45 a.m.) STABILITY OF THE CHROMlA LAYER ON STEELS IN FLOWING NONEQUILIBRIUM H2-H20-CHI.-CO MIXTURES: H. J. Grabke, P. C. Prasannan, and E. M. M;';'11er, Max-Planck Institut f~r Eisenforschung GmbH, 4 Dusseldorf, West Germany

The stability of the oxide layer on Fe-12.5%Cr, Fe-18%Cr-lO%Ni, and Fe-25%Cr-20%Ni was tested in a flowing, non-equilibrium gas mixture at 950°C. The samples were preoxidized in H2-H20; the carbon activity was then raised stepwise by adding CH4. CO is formed on the surface by the catalytic reaction CH4 + H20 -+ CO + H2' The conversion of oxide to carbide starts at the end of the 'sample where PeD has its highest and PH20 its lowest value. Oxidation, conversion, and catalytic reaction were monitored by gravimetry and co determination. The conversion starts when the steady state of ac and ao on the surface approaches the value for the equilibrium of oxide and carbide. This steady state valu~ is mainly determined by the reactions of l:i2, H20, and CO, and there is ve-ry little interaction of CH4 with the oxide surface.

(9:15a.m.) OXIDATION AND HOT CORROSION OF DIRECTIONALLY SOLIDIFIED EUTECTIC ALLOYS: G. L. Leatherman and N. S. Stoloff, Materials Engineering Dept., Rensselaer PolytechniC Institute, Troy, NY 12181.

The oxidation and hot corrosion behavior of directionally solidified eutectic alloys will be reviewed. Thermal stability, effect of microstructure, and reaction kinetics will be examined. Special emphasis will be given to the work of Professor Shatynski and his associates.

(9:45 a.m.)

Break

(10:00 a.m.) THE ROLE OF ACTIVE ELEMENTS IN THE OXIDATION BEHAVIOR OF MCrAlY ALLOYS: R. D. Sisson t Jr. and R. R. Biederman, Materials Engineering Laboratories, Mechanical Engineering Dept .• Worcester Polytechnic Inst., Worcester, MA 01609, and J. A. Nesbitt, NASALewis Research Center, Cleveland, OH 44135.

The effects of additions of active elements (e.g., Zr, Hf) on the oxidation behavior and oxide development in (Ni,Co)CrAIY alloys have been experimentally investigated by analytical electron microscopy. Emphasis is given to the distribution of the active elements in the various phases. The resul ts are discussed in terms of the thermodynamics of new phase formation and the appropriate binary and ternary phase diagrams. The possible roles of the active elements in promoting oxide adherence will be discussed.

(10:30 a.l'I.)

(10:30 a.m.) AN ANALYSIS OF MICROSEGREGATJON DURING CELLULAR AND DENDRITIC SOLIDIFICATION IN A BINARY ALLOY MELT: V. Laxmanan, Visiting Scientist, NASA Lewis Research Center, Cleveland, OH 44135 and Research Engi neer, Oepartmeht of Metallurgy and Materi a 1s Sci ence, Case Western Reserve Uni vers i ty, C1 eve1 and, OH 44106. Microsegregation occurring during cellular and dendritic solidification may be satisfactorily described by a simple analysis due to Bower, Brody, and Flemings. This analysis agrees remarkably well with available experimental data In both binary and mu1 ticomponent all oys. Thei r analysis, however, predi cts an increasing amount of eutectic (or second phases) in the structure with increaSing growth rates; reaching the maximum value given by the classical Scheil equation. It thus fails to predict the reduced amounts of eutectic observed in rapidly solidified alloys. A simple model, based on a modification of the Burden and Hunt analysis, overcomes this limitation. It will be shown that the average composition of the liquid plus solid mixture, during solidification, is always greater than the initial alloy composition; in the present model as well as in the earlier models.

A CONTRIBUTION TO OXIDE SCALE ADHERENCE:' J. G. Smeggll, A. W. Funkenbusch, and N. S. Bornstein, United Technologies Research Center, East Hartford, (:T 06108

Additions of reactive elements such as Y, Zr, and Hf at < 0.1 wt.% levels as either elemental metals or oxides have been demonstrated to enhance oxide scale adherence. Despite extensive research in this area, an accepted me"chanism to account for this improvement is lacking. Based upon in situ Auger spectroscopy and cyclic oxidation experiments, a~chanism to support the benefits of reactive elements is proposed. Elements such as S, P, etc., which are normally present in < 100 ppm concentrations, can segregate to the metal-protective scale interface, degrading adherence by formation of a liquid, a brittle phase. physical adsorption, or by gas phase reactions at the interface. ReactiVe elements would prevent such effects by the formation of stable refractory compounds with the segregating elements. *Research support by the Office of Naval Research, Contract No. NOOOl4-S2-C-06lS.

76 • TMS-AIME Annual Meeting Program (9:37 a.m.)

(11 :00 a.m.) W. J. Sherwood and S. R. Shatynskiii , Rensselaer Polytechnic Institute, Troy, NY 12181

OXIDE SCALE ADHERENCE ON STEELS:

THE STUDY OF OXIDE SCALES ON ION- IMPLANTED Ni -Cr AND STAINLESS

STEEL BY AEM: C.H. Yang, G.E. Welsch, P.A. Labun and T.E. Mitchell, Case Western Reserve University. 10900 Euclid Avenue Cleveland, OH 44106.

The adherence of the oxide scale on steels is influenced by the difference in thermal expansion coefficients between metal and oxide, the texture of metal prior tp oxidation. and the oxidation temperature. This study has examined the effects of these variables on oxide scale adherence on 1018 plain carbon steel, 304 austenitic stainless steel. and 430 ferritic stainless steel oxidized at 900-1100°C. Oxide microstructure and prior surface finish played a major role in oxidation of all three steels, while oxide composition was important in the type 304 steel. The 1018 steel oxidized at 900 and 1100°C exhibited general exfoliation, hut increased adherence was exhibited at 1000°C. Oxide adherence behavior of all three steels can be explained in terms of oxide growth stresses, cooling stresses, surface texture, and oxide plasticity.

Analytical electron microscopy of transverse sections has been used to study the morphology of oxide scales from the gas/oxide to the oxide/substrate interface on stainless steel and Ni-Cr alloys implanted with La and Y respectively. EDS, STEM and microdiffraction techniques give information on meta1lographic structures and constituent distributions resulting from oxidation. The results show that it is possible to localize the distribution of the minor <;ldditions of La and Y. The corresponding microstructures of both implanted and unimp1anted specimens further show how the formation of oxide scale is modified by changes in diffusion processes. 'Consequently, the oxide scale becomes more adherent and exhibits higher oxidation resistance.

':Deceased.

(10:00 a.m.)

SURFACE ANALYTICAL TECHNIQUES FOR CORROSION STUDIES III: Gaseous Corrosion Sponsored by the TMSIMSD Corrosion and Environmental Effects Committee Wednesday, February 27, 1985 8:30 a.m.

Diplomat Sheraton Centre

Session Chairmen: A. Joshi, Lockheed-Palo Alto Research Laboratory, Palo Alto, CA 94304; S. M. Bruemmer, Battelle Pacific Northwest Laboratories. Richland, WA 99352 (8:30 a.m.) OBSERVATIONS IN-SITU OF THE EFFECT OF MICROSTRUCTURAL FEATURES ON THERMAL OXIDATION OF STAINLESS STEEL:* A.S. Nagelberg and R.J. Anderson; Sandia National Laboratories; LlVermore. CA. A Raman microprobe has been combined with an optical microscope hot-stage to pennit observations at a microstructural level of the initial corrosion scale fonnation occurring on a metallic substrate. With this equipment, measurements can be made insitu at >1 micron spatial resolution and at temperatures exceeding 1250K. Surface features. such as grain boundaries. second phases, scratches. and imbedded particles. are known to lead to variable corrosion scale compositions and to act as sites for protective scale breakdown. The influence of these surface features on the developed scale structure and composition has been studied in-situ on 304SS and on Fe-Cr binary alloys in air and in an atmosphere of reduced oxygen pilrtial pressure at 900-1300K. Corrosion near the boundary of an molten salt droplet on a surface will also be examined. *Thi s work supported by the U. S. Department of Energy. (8:52 a.m.) THE USE OF ESCA TO DETERMINE THE MAGNESIUM ENRICHMENT IN THE SURFACE OXIDE ON ALUMINUM-MAGNESIUM ALLOYS: H. P. Leighly, Jr., University of Missouri-Rolla, Rolla, MO, 65401, A. Alam and R.N. West, University of East Anglia, Norwich, England, NR4 7TJ. Dilute alloys of magnesium (500 ppm and 1000 ppm) in aluminum were heated in very dry air at 850 o K, followed by severe quenching. Electron Spectroscopy for Chemical Analysis (ESCA) was used to analyze the composition of the surface oxide layer and to identify the ma
(9: 15 a.m.)

THE INFLUENCE OF STRUCTURE DECOMPOSITION IN HEAT -RESISTING STEEL ON PROTECTIVE BEHAVIOUR OF ZIRCONIA-CONTAINING COATINGS: A. Mandziej ~nd S. Mandziej; Laboratory of Materials Science, Twente University of Technology. P.O. Box 217. 7500 AE ENSCHEDE, The Netherlands. During SEM/EDS stUdies on the sol-gel method deposited, 850°C free-air baked, zirconia-containing coatings on AISI 314 type steels. characteristic sub-coating formed crystals were observed. These crystals appeared to assist the cracking tendency of the coating and to influence its protective behavior. The distribution of the sub-coating grown crystal s and the recorded changes in element concentrations suggested that their origin was from a solid-solution decomposition of the steel. Therefore. attention was paid to the phase composition and transformations in steel. and analytical TEM/STEM/EDS was used to identify the probab 1e sources of i nhomogenei ti es in the sub-coat i ng formed oxide scale. (10:30 a.m.) FOURIER TRANSFORM INFRARED REFLECTION SPECTROSCOPY STUDIES OF THE DEGRADATION OF PROTECTIVE COATINGS ON STEEL: Tinh Nguyen, Building Materials Divi~ion, National Bureau of Standards. Washington, D.C. Diffuse refl ectance and refl ect ion - absorpt ion techni ques i nterfaced with a Fourier transform infrared spectrometer were used to study the degradation at the interface of protective coatings and steel sub~trates. Polybutadiene. epoxide and polyurethane clear coatings were spin coated on low-carbon steel surfaces to give coatil1g thicknesses of from 0.3 to 2 um. The coated specimens together with the free films of the same coatings were exposed to corrosive environments and the FTIR spectra were taken at different exposure time intervals up to 3 months. IR spectra obtained show considerable changes in both the intensities and shapes of the OH band of the epoxide, the NH and NCO bands of the polyurethane and the CoO band of the polybutadiene coating with increasing ex~osure to the test environment. Both diffuse reflectance and reflection-absorption techniques appear to be valuable tools for studying the degradation of protective coatings. particularly at the interface beneath coatings. (10:52 a.m.) GAS-SOLID REACTION BETWEEN NICKEL AND H2 S/H2 GAS MIXTURES AT 400-

5Z0°C: R. Y. Lin, Department of Haterials Science and Metallurgical Engineering, M.L. 1112, University of Cincinnati, Cincinnati, OH

45221.

The corrosion of nickel under gas mixtures of HZS and HZ has been studied applying a thermogravimetric analysis (TGA) technique. The parabolic rate r,eaction kipettcs has been observed for all thE experiments. The x-ray diffraction phase analysis showed that thE activity of' sulfur at the equilibrium between the y-Ni6s5 phase and the O-NiS phase is smaller than that indicated in the literature. At times longer than 50 hours of sulfidation, it is difficult to distinguish parabolic rate from linear rate due to the slow reaction. The surface of sulfide scale and cross sections have also been examined using the scanning electron microscopes and EDX.

J. K. Doychak, T. E. Mitchell andJ.L. Smialek, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106. SURFACE OXIDE MORPHOLOGIES ON S- NiAl,

The oxidation of B-NiAI involves formation o:f A1 2 0 1 . as the primary oxide phase. At lower temperatures or short El.mes, the oxidation kinetics are still in the transient stage when metastable Al phases predominate, such as y-A1 2 0 3 and IS-AI 20 r However wrt~ longer times and higher temperatures (approximat~ly lOOO°C), the oxide transforms to a-Al203 at whi-:h steady state conditions are achieved. During transient stages, the surface morphologies of the oxide have been found to vary from crystallographic plates to needlelike morphologies to featureless, flat scales depending upon metal orientation. After the transformation to a-A1 2 0 3 , the different metal orientations appear to evolve various stages in the formation of the "lacey" morphology of oxide, commonly associated with Al 2 0 3 formation on B-NiAl. The implications of metal orientation and oxide morphology on scale growth rates will also be discussed.

°

*This work was partially supported by University Research Council of the University of Cincinnati.

(11: 15 a.m.) OXIDATION OF Si-CONTAINING Ni-BASE ALLOYS:

G. H. Meier and

F. S. Pettit, Department of Metallurgical and Materials Engineering, Universi ty of Pi ttsburgh, Pittsburgh, PA 15261 The kinetics and mechanisms of air oxidation of binary Ni-Si and ternary Ni-Cr-S! and Ni -Al-Si alloys have been lnves tiga ted in the temperature range 700 to llOOae. This presentation will focus on the charac teriza tion of the oxide layers formed on these alloys and how the layers influence the oxida tion kine tics. The experimen tal techniques utilized include scanning elec tron microscopy, energy-dispersive and wavelength-dispersive x-ray analYSiS, Auger electron spectroscopy, transmission electron microscopy, and selected area electron diffraction.

TMS-AIME Annual Meeting Program - 77 (11 :37 a.m.) THE EFFECT OF SULFUR ON THE OXIDATION OF NiFe SURFACES • RIOJ. Lad, A.G. Schrott and J.M. Blakely, Materials Science and Engineering, Cornell University, Ithaca, New York 14853

The infiuence of sulfur on the initial oxidation of a Ni Fe (100) alloy surface has been studied using Auger electrog:Dsp~g­ troscopy and low energy electron diffraction. OXide growth kinetics were measured at 373K and 773K for the clean surface as well as for surfaces covered with sul:monolayer amounts of sulfur. On the clean (lOO) alloy surface, pronounced Fe segregation accompanies the formation of a (Ill) cubic oxide. However, the presence of an ordered c (2x2) sulfur phase at ~ monolayer coverage prevents the sticking of 02 molecules and the alloy surface retains the bulk composition. For sulfur coverages below l.;,: monolayer, oxide islands form in coexistence with sulfur-rich c (2x2) domains. For each fixed sulfur coverage, the 0 uptake rate decreases with increasing temperature suggesting Ehat a higher sulfur mobility lowers the oxide nucleation probability. Other effects of temperature and sulfur coverage on the mechanisms of oxide growth will be discussed • • Supported by DOE contract #DE-AC02-79ERl0501.

TMS-AIME Institute of Metals Lecture & Robert F. Mehl Medalist 11:45 A.M. Wednesday, February 27, 1985 Sheraton Centre Hotel Imperial Ballroom B Lecturer: Peter Haasen Professor University of Gottingen West Germany Topic: "The Early Stages of the Decomposition of Alloys"

operating temperatures with a tungsten carbide-tipped hardness probe attached to an electronic load cell. Hardness was found to be a functi on of temperature and the bath content of the crust as well as the bath composition. Fine alpha alumina particles form in the crust as a consequence of bath contact with the feed and the strength of crust appears attributable large ly to its bath component. Therefore. those a I umi na properties which enhance bath penetration have an effect on crust hardness.

(2:30 p.m.) INTERACTIONS OF ALUMINA WITH CRYOLITE-BASED MELTS. J. Gerlach arid G. Winkhaus. Tech. Univ. Berlin and Vereinigte AlumlnlumWerke AG. Bonn. FRG. In a series of laboratory investigations the interactions between metallurgical aluminas and cryolite-based melts were studied. The kinetics of the dissolution of aluminium oxide in cryolite melts were determined and the influence of melt composition on the dissolution rate was examined. Al so. the foronation and properties of crusts formed on addition of different grades of aluminas are discussed as well as the formation of sludge.

(3:00 p.m.) ELECTRICAL CHARGE ON METALLURGICAL ALUMINA: T. J. Johnston, and R. C. White, Reynolds Metals Co., Reduction Laboratory, Sheffield. AL 35660.

Frictional electrification, caused whenever dry bulk alumina is moved, is responsible for the generation of static charge. Under separate conditions, alumina can be charged above 5,000 volts. Electrical charge can effect the particle interaction in aluminas which can change the normal low characteristics of alumina powder J thus causing anomalies in transfer systems. A mechanism is proposed for the generation of Charge together with a method for its dissipation. .

(3:30 p.m.)

Break

(4:00 p.m.) "METHODS FOR EVALUATING PARTICLE SIZE SEGREGATION DURING STORAGE TANK DISCHARGE": J. W. Novak. Jr. and W. C. Sleppy, Aluminum Company of America, Alcoa Laboratories,. Alcoa Center, PA

TMS-AIME Light Metals Luncheon 12:00 Noon Wednesday, February 27,1985 Sheraton Centre Hotel Imperial Ballroom A Speaker: Herbert C. Clough Group Vice President Alumax, Inc. San Mateo, California Topic: "Uncertainties Facing the Aluminum Industry"

A comprehensive i~vestigation of particle size segregation . during discharge of alumina storage tanks has provided new insights on experimental design, sampling practices and analytical measurements. This paper presents an overview of previous approaches used to describe particle size segregation effects, and discusses our attempts to develop more effective segregation descriptors which are collectively called "Segregation Figures of Merit" (SFOM). Examples include segregation index and degree of segregation. Data is presented which demonstrates use of SFOM to determine the primary source of size segregation during an alumina storage and transfer operation. The SFOM are further used to evaluate the effectiveness of operation modifications made to minimize size segregation at the facility.

(4:30 p.m.)

WEDNESDAY PM ALUMINA & BAUXITE V: Alumina and Smelting Joint Session Sponsored by TMS Light Metals Committee Wednesday, February 27, 1985 2:00 p.m.

Royal Ballroom A Sheraton Centre

Session Chairmen: A. Cruz, Aluminum Company of America, 1501 Alcoa Building, Pittsburgh, PA; Jim Todd, Kaiser Aluminum, 300 Lakeside Drive, Oakland, CA 94643

(2:00 p.m.) HARDNESS OF HALL CELL CRUSTI A, J. Becker, T. R. Hornack and R. M. Mazgaj, Aluminum Company of Aiiii!rica. Alcoa Technical Center. AI coa Center. PA 15069. Good Hall cell crust is necessary to maintain cell heat balance. to minimize fluoride losses and to $upport cell feed. Hardness of I aboratory grown Hall cell crust has been measured at

AN INVESTIGATION OF HOW THE EQUIPMENT FLOWSHEET FOR THE CALCINATION PROCESS INFLUENCES THE PHYSICO-CHEMICAL PROPERTIES OF ALUMINA USED FOR ELECTROLYSIS: G. V. Telyatnikov, T. A. ArlyukJ N.S. Shmorgunenko J VAMI Institute, Stredmye Prospect 86 199026, Leningrad, USSR.

Alumina produced in rotary calciners is noted for non-uniform phase composition, high~r content of moisture and silica (due to wear of refractories) compared to the best rotary kilns. The use of fluidized bed calciners ensures 18 to 20 percent reduction in specific fuel consumption and higher alumina qUlility manifested by uniform phase composition, lower residual moistur~, and stable phytl ico-chemical properties.

(5:00 p.m.) AN EFFECT OF THE ALUMINA QUALITY ON THE ALUMINIUM ELECTROLYSIS PROCESS: G. N. GopienkoJ N. S. Siraev, VAMI Institute, Stredmye Prospect 86, 199026, Leningrad, USSR.

Pilot test of alumina with 15 to 20 percent alpha modification and specific area of 60 to 80 sq. m. per gram for aluminium smelting proved a possibility for higher current efficiency, lower specific power demand, and fluorides comsumption. Study of physico-chemical properties of alumina fed to pots showed that moisture content in alumina drops over the period between the pot workings. Alumina layer next to the crust adsorbs upto 1.2 percent of fluorides. Besides specific area of this layer, is less than the upper layer and alpha alumina and plus 40 micron fraction content is higher than in upper layer.

78 - TMS-AIME Annual Meeting Program CAST SHOP TECHNOLOGY II Sponsored by the TMS Light Metals Committee Wednesday, February 27, 1985 2:00 p.m.

Georgian Ballroom B Sheraton Centre

Session Chairmen: Heinz O. Titze, Consolidated Aluminum, 1160 Westline, Industrial Drive, St. Louis, MO 63146, and Walter Haller, Alusuisse, Research & Development, CH-B034, Zurich, Switzerland

(2:00 p.m.) THE DEVELOPMENT OF THE ALPUR SYSTEMS FOR THE IN-LINE TREATMENT OF MOLTEN ALUMINUM AND ALUMINUM ALLOYS: J. &ldstein, Servimetal Pechiney, Chambery, France.

During the last three years, more than twenty Alpur units have been installed in both primary and secondary alumirium smelters worldwide. Statistical results have been collected from the 1,000,000,000 Ibs which have been treated by means of Alpur. They show a consistent removal of hydrogen as well as of non metallic inclusions f rom the melt. The range of available systems has been enlarged to f it the requirements of most continuous or DC casting installations.

(2:30p.m.) AN EXPERIMENTAL TECHNIQUE FOR DETERMINING SPECIFIC CAKE RESISTANCE VALUES IN THE CAKE MODE FILTRATION OF ALUMINUM ALLOYS. C. E. Eckert, R. E. Miller., Alcoa Technical Center, Alcoa CenterPA R. Mutharasan, D. Ape1ian, Drexel University. Philadelphia PA An important parameter in the cake mode filtration of metals is the specific cake resistance, a, which is functionally related to the performance and pressure drop characteristics of the filter. The mathematical relationships between experimentally measured variables and a were presented in the authors' previous paper. This paper discusses the experimental determination of a from constant pressure experiments in three aluminum alloy systems. The apparatus used for the experiments is described, and the application of a to constant rate cake mode filtration is demons t ra ted. (3:00 p.m.) DUFI: A CONCEPT OF METAL FILTRATION, Dr. J.-D. Bornand, Dr. K. Buxmann, Swiss Aluminium Ltd., R&D, 3965 Chippis, Swi tzer1 and. The concept of metal filtration using a petroleum coke filter bed is one way of removing hydrogen. alkaline metals and nonmetallic inclusions from liquid aluminum. 15 years of practical experience with this type of melt purification has now led to an improvement in the equipment to a degree that it can be easily handled at low cost and with a high reliability. The OUFI filter especially can eliminate alkaline metals without reactive gases. The paper deals with our experience of the two and three part filters of the last generation. 15 and 40 tph. The advantages of DUFI filters are discussed such as different applications, particularly when combined with rigid media filters of the SELEE type or the latter in combination with a OUFI tandem system.

(3:30 p.m.) INDUSTRIAL APPLICATION OF OPEN CERAMIC FOAM FOR MOLTEN METAL FILTRATION, L.J. Gauck1er, M.M. Waeber, Swiss Aluminium Ltd., Research & Development, 8212 Neuhausen, Switzerland, C. Conti, M. Jacob-Du1iere, Facu1te Poly technique de Mons, Belgium Ceramic foam filter beds were used for industrial filtration of aluminum and iron. Results are compared with laboratory experiments which are in good agreement with trajectory analysis of deep bed filtration for the early stage of filtration. The correl ations between structura 1 characteri sti cs of the fil ter medi a, fil tration parameters, concentrati on and nature of impurities, filter and lifetime are given. In addition the most important practical parameters influencing efffciency and 1 i fetime of fil ters in i ndustri a 1 use are di scussed.

(4:00 p.m.)

these defects. This control based on specific sensors and computerization allows to cast automatically close to the maximum productivity without defect on the strip. An example of industrial development of automatic control of a Jumbo 3C caster is described. (4:30 p.m.) INDUSTRIAL APPLICATION OF ELECTROMAGNETIC CASTING (£MC) OF ALUMINIUM, Dr. R. Sautebin, Swiss Aluminium Ltd. Research & Development, CH-3965 Chippis. Swiss Aluminium Ltd. has developed its own £MC technology. The most outstanding features are a completely automated-process with controlled cooling and solidification of the aluminium, adjustable molds and non-contacting metal level sensors. During 6 years of industrial production, the EMC process has proven its reliability, safe operation, high productivity and economical benefits. At present more than 300000 metric tons/year of EMC ingots of a wide product range are produced by A1usuisse EMC technology, and the production is rapidly growing. Scalping and edge trimming during further processing of EMC ingots can be reduced or eltminated for several product groups resulting in substantial savings. The Alusuisse EMC technology has been licensed to other aluminium producers.

DIFFUSION TMS-AIME General Abstract Session Wednesday, February 27, 1985 2:00 p.m.

Jefferson Suite Sheraton City Squire

Session Chairman: N. L. Peterson, Argonne National Laboratory, Bldg. 212,C206,9700 S. Cass Ave., Argonne, IL 60439

(2:00 p.m.) COUPLED DIFFUSION OF CARBON ATOMS AND VACANCIES IN PLATINUM:* P. Ferguson, K.H. Westmacott, U. Dahmen and R.M. Fisher+, ~laterials and Molecular Research Division, Lawrence Berkeley Laboratory, University of California, Berkeley, CA., 94720, +Center for Advanced Materi a 1s, Lawrence Berke 1ey Laboratory, University of California, Berkeley, CA. 94720. Direct evidence for the interstitial analogue of the reverse Kirkendall effect has been found in experiments of carbon diffusion through platinum membranes at 700-9DO°C. The carbon transport through the foil was accompanied by the formation of protrus; ons and depress ions in the carburi zed and decarburi zed surfaces respectively. The magnitude of the counterfl ux of platinum atoms suggests that a significant fraction of the carbon atoms are strongly bound to vacancies. An analysis based on Lomer's· equation yielded a carbon atom-vacancy binding energy! EB 2.0. Sev . "This work is supported by the Di rector, Offi ce of Energy Research, Office of Basic Energy Sciences, Materials Sciences Division of the U.S. Department of Energy under COntract No. DE-AC03-76SF00098.

(2:20 p.m.) USE OF AEM TO MEASURE INTERDIFFUSlOO COEFFICIENTS IN Fe-Ni ALLOYS: D. C. Dean and J. 1. Goldstein, Dept. of Metallurgy and Ma terials Engineering, Lehigh Univers ity, Bethlehem, PA 18015. The interdiffusion coefficients in Fe-Ni alloys were evaluated in the ferrite (0') and austenite (V) phases at temperatures from 925°C to 550°C. Analytical electro~ microscopy (AEM) was used to measure the Ni concentration gradient perpendicular to a diffusion couple bond interface OVer distances as small as 1.0 ~ra Grain boundary 'diffusion regions were also avoided by using AEM. The diffusivity in ferromagnetic ct was 1 to 2 orders of magnitude lower than previously measured by tracer diffusion. The diffusivity in austenite agreed with the extrapolated data of Goldstein et a1. (1965) from temperatures above lOOOoC. The addition of less than 0.25 wt% P caused an order of magnitude increase in the Ni diffusivity below 700°C in both Ci and y, and i's explained by an increase in equi librium vacancies due to the presence of soluble P in Q' or V FeNi.

(2:40 p.m.)

OPTIMISATION OF 3C ROLL CASTER BY AUTOMATIC CONTROL : S. J. Bercovi ci, Cl!gl!dur Pechiney, Centre de Recherches et de Olive 1oppement, BP 27, 38340 Voreppe, France.

mlPlITER SIMULATION OF DIFRJSIONAL BEHAVIOR IN TERNARY SINGLE PHASE ALLOYS:' N. deLanerolle and L.L. Seigle, Department of Materials Science & EIlgmeenng, State University of New York, Stony Brook, NY 11794

The productivity limitations of twin roll continuous strip casting processes are due to the occurrence wfth increasing speed of a certain number of defects on the strip such as solidification defects or sticking to the rolls which either impair the quality of the strip or lead to interruption of casting. The orl'gin of these defects has been extensively ana lysed and procedures have been set up to predi ct them and to correct some of the casting parameters in order to avoid

A theoretical investigation was undertaken using hypothetical couples to show the following: (1) The individual effects of the two cross diffusion coefficients on diffusional behavior. (2) See how the direct diffusion coefficients modify or influence the effects of the cross coefficients. These effects were' studied with respect to two types of curves used in diffusion studies-the concentration profile and the diffusion path. SpeCifically, the

TMS-AIME Annual Meeting Program - 79 phenomenon of uphill diffusion, the spread of the concentration profile and the effect on the maxirrrum and minirrrum of the concentration profile will be described. In the case of the diffusion path, the effect on the shape and on the position of the peaks will be discussed. * Thi s nat' 1. is based upon work suoported by Nat' 1. Sci. Found. Grant HDMR8022794 (3:00 p.m.) 1HE DIFFUSION EQUATION: A RANDOM WALK METHOD OF G. E. Murch, Argonne National Laboratory, Argonne, IL

SOLUTION:" 60439.

The central problem In many macroscopically defined diffusion problems is the definition of initial and boundary conditions and the subsequent solution of the diffusion equation. When the diffusion coefficient is a function. of concentration and/or distance, an analytical solution is generally not accessible. A very general but particularly simple Monte Carlo method based on the simulation of random walks will be discussed with example cal,culatiaDe to include dislocation pipe and grain boundary diffusion, diffusion limited evaporation and absorption/desorption kinetics from a membrane.

·Work performed under the auspices of the Office of Basic Energy Sciences, Division of Materials Sciences, U .5. Department of Energy, under Contract w-31-109-Eng-38.

(3:20p.m.) QUATERNARY DI FFUSION IN THE Ni -Cr-Co-Mo SYSTEM AT 1 300°C :" J. A. Heaney. M. A. Dayananda. School of Materials Engineering, Purdue University, W. Lafayette, IN 47907 Multicomponent diffusion was investigated with solid-solid diffusion couples in the a(fcc) region of the Ni-Cr-Co-Mo system at l300°C for the determination of diffusion paths and diffusional interactions among the components. The termi na 1 alloys for the couples were selected to have similar concentrations of one or two of the components. The concentrati on profil es were exami ned on the basis of a relative concentration parameter for each component and analyzed for interdiffusion fluxes. The quaternary diffusion paths were represented analytically with the aid of path parameters. The paths were described as space curves by plotting three independent concentration variables along the axes of a cube.

*Research supported by U.S. Department of Energy under contract DE-ACO 2-81 ERl 0814. (3:40 p.m.) THE RELIABILITY OF FINITE DIFFERENCE METHODS FOR THE SOLUTION OF DIFFUSION AND TRAPPING EQUATIONS:' R. C. Frank and S. P. McManus, Augustana College, Rock Island, IL 61201, and L. E. Rehn, Argonne National Laboratory, Argonne, IL 60439.

Nath models involving diffusion and trapping differential equations are required to obtain trap binding enthalpies from experimental data and yet they ar~ difficult to check. An effort has been made to assess, under a variety of conditions, the reliability of the results of calculations made using the finite difference method of Caskey and Pillinger by comparing them with results obtained using the GEAR codes. While C-P calculations were' made on a small FORTRAN language microprocessor and the GEAR code calculations on a large computer, the agr~ement in most of the cases tested was very good. Difficulties in the use of both methods are discussed. *This work was supported by NSF Grant DMR-8406248 and by the Department of Energy.

(4:00 p.m.) INTERDIFFUSION IN THE Ta-W SYSTEM, A. D. Romig, Jr., M. J. Cieslak, C. R. Hills, Sandia National Laboratories, Albuquerque, NM 87185

Interdiffusion in the Ta-W, system, a continuous bcc solid solution, has been studied in the temperature range 1300 to 2l00°C using single phase diffusion couples prepared by CVD. Interdiffusion in the couples was measured by X-ray microanalysis in the electron microprobe and/or'\.othe analytical electron microscope. The chemical diffusivity, D, was determined by the classical Matano-Boltzman technique. Fine inclusions at the Ta/W interface served as Kirkendall markers, allowing for the determination of the self-diffusion coefficients, DW and DT ' vi,t the Darken analysis. Over the entire composition range Da > D > DW' The diffusion coefficients, and hence the activatI~n energies (Q) were compositionally dependent.'\.o The variations in Q with composition (pure Ta to pure W) were: Q:'C 110 -> 130 -> 120 kea1/mole, Q : 'C 110 .. 129 -> 120 keal/mo1e and QW: 'C 109 -> 130 -> 140 kca11i1io1e. "This work performed at Sandia National Laboratories supported by the U.S. Department of Energy, Contract No. DE-AC04-76DP00789.

(4:20 p.m.) GROWTH OF A SPHERICAL PRECIPITATE FROM SOLID SOLUTION: Hast ic Effects V.J. Laraia 1 , P.W. Voorhees:'9 and W.C. Johnsonl. I Dept • Metallurgical Engineering and Materials Science Carnegie-Mellon University, Pittsburgh, PA 15213 and ?National Bureau of Standards, Gaithersburg, MD 20899.

Solutions are presented for the growth of spherical particle into a supersaturated matrix. Elastic effects due to precipitate misfit and to differing partial molar volumes of the two compon-ents are accounted for explicitly. Defining the diffusive flux with respect to the reference lattice allows the flux to be written in terms of a composition dependent diffusivity. Solutions are presented to the quasi-stationary and time-dependent problems.

(4:40 p.m.) SIMULTANEOUS DETERMINATION OF DIFFUSION COEFFICIENT AND PARTIAL PRESSURE OF TIN AND TITANIUM IN ZIRCONIUM: R.B. Zee, R. D. Davidson and J. F. Wat ters 9 Atomic Energy of Canada Lim! ted. Chalk River Nuclear Laboratories, Chalk River, Ontario KGJ IJO Canada

The analytical solution for the differential equation governing the radial diffusion of solute atoms in a cylindrical rod with the condition that the loss of solutes at the surface being proportional to the surface concentration will be presented. This solution can be used to determine both the diffusion coefficient and the partial vapour pressure of solutes in simple alloys. Specimens of zirconium with 4 atomic % Sn or 5 atomic % Ti were electrically heated in the S-phase in a vacuum better than 10- 8 torr. The radial concentration profiles in these specimens were then determined using Energy Dispersive X-ray (EDX) analysis in a SEM. Comparing these profiles with the ~alculated ones, we found that Sn and Ti both diffuse via a vacancy mechanism in S-Zr. The experimental resul ts also indicate that there is a strong binding between the Sn solute atomH and the Zr matrix whereas the Zr-Ti system obeys Raoult' s law quite well.

DEFORMATION IN HIGH TEMPERATURE ALLOYS Sponsored by the TMS High Temperature Alloys Committee Wednesday, February 27, 1985 2:00 p.m.

Province Suite Sheraton Centre

Session Chairman: P. K. Wright, General Electric Company M87, 1 Neumann Way, Cincinnati, Ohio 45215 (2:00 p.m.) HOT WORKABILITY OF REN{ 95*: Janine C. Borofka and John K. Tien, Center for Strateg i c Materi a 1 s, Henry Krumb School of Mi nes, Columbia University, New York, N.Y. 10027. In this study, the workability of as-HIP Ren~ 95 is examined using true strain rate controlled tensile test data. True stress-true strain curves were generated over a range of temperatures and true strain rates and regions of superplastic deformation (strain rate exponent m greater than 0.3) were identified. For example, at a true straln rate of 5x10- 4 sec l , as-HIP Rene'95 exhibits decreasing m values of 0.49, 0.38, and 0.21 at the increasing temperatures of 1050, 1100, and 1150 0C respectively. The data is compared to other studies of Rene' 95 to show the operative relations among grain size, processing technique, strain rate, and temperature as they pertain to superplastic behavior. The selection of optimum parameters for superplastic hot working of Rene' 95 is discussed, in addition to the application of the results to the science of hot isostatic pressing (HIP) kinetics, especially with respect to superplastic deformation of individual powder particles. "This work was sponsored by the Air Force under contract AFOSR-820352A and monitored by Or. Allen H. Rosenstein. (2:25 p.m.) IN 738: CAST VS. WROUGHT": Michael E. Casey, Erik A. Schwarzkopf and John K. Tien, Center for Strategic Materials, Henry Krumb School of Mines, Columbia University, New York, N.Y. 10027. High temperature mechanical and fatigue properties of various forms of IN 738 were studied. IN 738, a y' strengthened nickelbase superalloy, is traditionally processed as a cast alloy. By appropriately adjusting rolling temperatures, a wrought version of this alloy was produced. The aim of this study was to ascertain the direct effect of various processing channels on the high temperature mechani ca 1 properti es of the result i ng alloys. Hot tensile, static creep, and high temperature high mean stress fatigue tests were conducted on both wrought and cast versions of IN 738. It was found that material form, as determined by its prior processing history, had an effect on lifetimes during high mean stress fatigue tests and a 1so on materi a 1 pro pert i es du ri ng hot tensile and static creep tests. *Thi s work was supported by the NASA-LEWIS Research Center by research grant NAG3-57 under the monitorship of Joseph R. Stephens and Coul son Scheuermann.

80 - TMS-AIME Annual Meeting Program (2:50 p.m.) TEI:PERATURE, ORIENTATION, AND TENSION-COI1PRESSION DEPENDENCE OF YIELOING IN A SINGLE CRYSTAL NICKEL-BASE SUPERALLOY: R. V. Miner, T. P. Gabb, J. Gayda, NASA Lewis Research Center, Cleveland, OH, and K. J. Hemker, University of Cincinnati, Cincinnati, OH. Tensile and compressive yield strengths of a single crystal nickel-base superalloy have been measured at temperatures from ambient to 980 0C for various crystallographic orientations. The alloy, designated N-4, has the composition 3.5 Al, 0.75 Ti, 4 Ta, 0.5 Nb, 9 Cr, 1.5 110, 6 14, 7.5 Co, and balance Ni (w/o). Operatin9 slip systems were identified by slip trace analysis, tensile axis rotation, and dislocation Burgers vector analysis. Orientations near [lllJ were found to slip on the primary cube system, even at room temperature. The range of orientations exhibiting cube slip increased with increasing temperature. Orientations yielding by octahedral slip showed considerable deviations from Schmid's Law and tension-compression anisotropy. Th is was mos t pronounced at i ntermedi ate temperatures. The data were correlated well by a model of Lall, Chin, and Pope which considers the effect of the applied stress in resisting octahedral slip by aiding two steps in the Kear-Wilsdorf locking mechan i sm.

(3: 15 p.m.)

THE EFFECT OF ORIENTATION ON THE CREEP-FATIGUE BEHAVIOR OF A SINGLE CRYSTAL NICKEL-BASE SUPERALLOY·: R. Richards-Frandsep, A.H. Cooper and J. K. Ti en, Center for Strateg i c Materi a 1 s, Henry Krumb School of Mines, Columbia University, New York, N.Y. 10027. Previous studies on superalloy single crystals have shown very strong orientation dependent creep properties. Gas turbine appl ications, however, are usually creep-fatigue limited. This study reports on the orientation dependent creep-fatigue behavior of aNi-base superalloy single crystal. Tests in the 1 Hz fatigue frequency range showed no deleterious orientation effects while tests at the low frequency range showed the creep orientation effects previously reported. These results indicate that the deleterious orientation effects on the creep and stress rupture resistance of superalloy single crystals may not occur during fatigue loading; the transition from the creep limited regime to the fatigue regime is under study and will be discussed. ·We thank Rocketdyne Division and the Science Center of Rockwell International Corporation for providing specimens and facil ities for this study.

(3:40 p.m.) J.J. Stephens, Nix, Dept. of Materials Science and Eng., Stanford University Stanford, Ca. 94305 OFF-AXIS CREEP PROPERTIES OF INCONEL MA 754:*

w. D.

The cretSP properties of MA 754 specimens aligned with the stress axis 20 from the longitl1dinal direction have been examined in vacuum at 1093 0 C. Above 100 MP'a. the minimum strain rates measured are essentially identical to those of longitudinal creep specimens, however, the creep ductility is lower. Below 100 MPa, grain boundary sliding dominates and a stress exponent of 2.2 is me,'1sured. Cavitation of both longitudinal and transverse grai.n boundaries is observed. I he activation energy for creep in the regime where grain boundary sliding dominates was found to be 113.8 kcal/n16le. This contrasts ,.... UI 1 an activation energy of 74.9 kcal/mole for dislocation creep in ~1A. 7,)4. Metallographic examination of deformed specimens will he discussed. *Work supported by Air Force Office of Scientific Research, AFOSR81-0022C.

(4:30 p.m.) III!CBANICAL BI!IIAVIOR OF PIli Ni AI-B ALLOYS:' 1-11 Chana. S.C. RUUla. Ind A. I. Taub. Goneral Blec/ric Corporate aosearch Ind Develop.,nt. Schenectady. New York. Alloyinl with an approprilte amount of Bind processina throulh the rapid solidificaUon .aJr.. intera.taUic Ni 3 AI-ba.. aUoy romlrkably ductile. ODe of the rapid lolidificatfon techniques. powder metallur,y method. hiS been applied in this study to prepare Ni 3 AI-B alloys • • 0 'that the mechaDicll bohavior of bulk .. aterill can b. evaluated. The ultimate tend Ie .trenath is unusually hi,h. wh,ich il attributable to the larae strain hard,ninl rate and the lar,e elonaation before frlcture occurs. Positive temperature dependence of yield strenath i. found up to 600'C; in contrast. tensile stren,th docrelses monotonically.a. te.perature is increa.ed. and .how. a rapid drop around 600 C. Po.sible aechanis •• to explain the phenOlll.nololY of pla.tic defor•• Uon in PIli Ni 3 AI-B alloys "UI be discu ... d.

ENERGY REDUCTION TECHNIQUES IN METAL ELECTROCHEMICAL PROCESSES VI Sponsored by TMS-AIME Electrolytic Processes Committee Wednesday, February 27, 1985 2:00 p.m.

Versailles Ballroom Sheraton Centre

Session Chairmen: James W. Evans, Department of Materials Science and Mineral Engineering, University of California-Berkeley, Berkeley, CA 94720; James E. Hoffmann, Exxon Minerals Corp., Houston, TX 77040

(2:00 p.m.) ELECTROLYTE FLOW PATTERNS IN MOLTEN SALT ELECTROLYSIS CELLS:

J. K. Koziol and D. R. Sadoway, Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue Room 8-109, Cambridge, MA 02139. Solid electrodeposits from molten salts are typically.incoherent, powdery, and/or dendritic. Fluid flow patterns in the electrolyte are being observed by a laser schlieren imaging technique in order to determine how mass transport affects the morphology of the metal deposit. Zinc is being deposited from a melt of ZnCI2-LiCl KCl. Current density, electrolyte composition, anode-cathode separation, and electrode orientation are varied. The electrolyte flow patterns and the reSUlting zinc deposits are studied in relation to changes in process variables. This work is sponsored by NASA under Contract NSG 7645.

(2:30 p.m.) ENERGY REDUCTION APPROACHES IN MAGNESIUM PRODUCTION R. Neelameqqham, Af1AX Maqnesium Coro., 238 N. 2200 fl., Salt Lake Clty, Otah 84116 and J. C. Priscu, Chem-Pro Consultants, Inc., 918 East Essex Dr., Las Veqas, Nevada 89107 A brief historical comparison of the qrowth of maqnesium and aluminum industry in the past century is oresented a10nq with unit enerqy' consumDtion for each metal. Hith the changi nq worl d economy, the energy pi cture and the forei qn dependency for raw materials in the production of aluminum, it is predicted that maqnesium demand will 00 UD at least threefold in the next fort,v years, while becoming cost competi ti ve wi th a 1umi num for several oroducts. Areas of fundamental research of industrial apolicability are pointed out by ana 1yzi nq the comoonents of energy consumpti on in the electrolytic production of maqnesium.

(4:05 p.m.) EFFECTS OF HOLD TIME ON LOW CYCLE FATIGUE OF TWO NICKEL-BASE

ALIGNED EUTECTICS by N. J. Bylina. D. J. Duquette and N. S. Stoloff, Materials Engineering Department, Rensselaer Polytechnic Institute, Troy. NY 12181

The strain-controlled low cycle fatigue behavior a"t 82SoC in argon of two advanced nickel-base eutectics, AG-170 and Nitac 14B, was studied. Heat treatment to alter the y/y' distribution was the principal experimental variable. Testing consisted of continuous cycling (12 cpm) and cycling with the imposition of a 2 minute hold at the maximum tensile strain. Both alloys obeyed the CoffinManson law. Aging was found to have no effect on fatigue life in continuous cycling. As 0.5. Nitac l4B displayed a reduction in fatigue resistance with a hold time, whereas aged Nitac 14B and aged AG-170 fell in the same scatterband as the continuous test results. The lack of a hold time effect on aged material is attributed to the development of a compressive mean stress and a decrease in fiber damage. AG-170 and Nitac 14B are superior in fatigue resistance to several current Ni-base superalloys. This work was supported by the Air Force Office of Scientific Research, under Grant No. 80-0015.

(3:00 p.m.) INERT ELECTRODES FOR ALUMINUM ELECTROLYSIS CELLS:

A. D. McLeod,

J. S. Haggarty, and D. R. Sadoway, Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue Room 8-109, Cambridge, MA 02139. In the traditional Hall cell, replacement of the carbon electrodes with inert electrodes could result in substantial energy savings during metal production and also facilitate the design of a bipolar cell. The electrical properties of candidate materials are being measured. The behavior of these materials is -also being studied in a laboratory-scale Hall cell. By laser processing it has been possible to make single crystal test specimens free of grain boundaries or porosity. Electrical conductivities have been measured for a variety of materials including monocrystalline TiB2 and various ferrites. The electrochemical dissolution of candidate anode materials in cryolite is being investigated by overvoltage measurements. This work is being supported by the U. S. Dept. of Energy by Contract DE-FG07-83ID12380.

TMS-AIME Annual Meeting Program - 81 (3:30 p.m.)

(2:20 p.m.)

IILUMINUM ELOCTRODEPOSITION FROM MOLTEN TETRACHLOROIILUMINATE MEDIA: MODIFICATION OF ELOCTROREDucrION KINETICS VIA ORGANIC ADDITIVES - J.P. Pemsler, V.R. Koch, M.D. Dempsey, J.K. Li tchfield, and S.E. Stone, Castle Technology Corporation, 52 Dragon Court, Woburn, MA 01801.

LAYERS: G. T. 11urray and D. A. Brigqs, Met. En99., Cal. Polyteeh. State Univ., San LU1S Obispo, CA 93407; J. P. Boufford, Northrop Ai reraft, One Northrop Ave., Hawthorne, CA 90250

'lHE PREVENTICN OF HYDRlGEN EMlRITl'LEMENT BY lnl-METALLIC SURFACE

Thick (O.7mm), adherent Al plates of good morphology were deposit<1 from molten NaA1C1 4 at current densities of up to 90 mA/cm. This was achieved by adding to the melt several organic addi ti ves, the presence of which enhanced Al nucleation as determined by cyclic voltammetry. In the absence of the additives, highly dendritic plates of poor qual i ty were ubiqui tous. The use of cycl ic vol tammetry to directly measure Al deposi ticn currents allowed us to evaluate the effect on morphology of a series of homologous additives. The results of this study may have general utility in elucidating additive/metal deposition chemistry. This study was funded by National Science Foundation SBIR Grant CPE-8115213.

G. J. Kipouros

and D. R. Sacloway, Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, .

Room 8-109, Cambridge, MA 02139. The e!ectrodeposition of molybdenum from molten salts is being studied in order to develop a technology capable of making refractory metal coatings on low-cost base metals. Initial experiments have shown that it is possible to electrodeposit molybdenum onto various substrates such as molybdenum, graphite, and tungsten from an electrolyte consisting of KCl-K3MoC16 at a temperature of 800 oe. This work is sponsored by the Dow Chemical Company.

(4:30 p.m.) RAMAN SCATTERING STUDIES OF MOLTEN SALT ELECTROLYSIS OF LIGHT METALS:* S.-Y. Yoon, J. H. Flint, G. J. Kipouros, D. R. Sadoway, Dept. of Materials Science & Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue Room 8-109, Cambridge, MA

(2:40 p.m.) MEASUREMENTS OF HYDROGEN IN PURE IRON, K. Hashimoto and M. Meshii, Dept. of Materials Science & Engineenng., Northwestern University, Evanston, IL 60201

(4:00 p.m.) MOLYBDENUM COATINGS BY MOLTEN SALT ELECTROLYSIS:

In a pxevioUs publicatian (Nelsen and MJrray-ME:I'. TRANS. A,March. 1984, p. 597) it was xeported that 15-5 PH stainless steel, sputter coated with a 5000 angstran surface layer of Ti02, was essentially :inm.Jne to hydrogen embrittl..eIrent. '!his work has been extended to include other non-rretallic coatings as well as thepnally grown oxide layers. Al2'l3 was particularly effective, requiring only 500 angstrcrns thickness to pxevent hydrogen eIrbri1:tl..eIrent as neasw:ed by subjecting tensile spec:ilrens to 16 hours of cathodic charging at a =rent density of 9 mII,Ian2 • Oxide layers thepnally grown during solution annealing in air also pxevented. embri ttl..eIrent mile oxide layers produced at aging temperatw:es substantially xeduced the degree of eIrbrittlement.

02139.

The evolution of hydrogen from pure iron was studied in an ultrahigh vacuum system in order to determine the hydrogen content and the state of hydrogen trapping for various hydrogen-charging techniques. The study revealed that electro-chemical charging at room temperature produced more strongly trapped hydrogen than quenching from high temperatures in a hydrogen atmosphere. The hydrogen evolution during isochronal annealing indicated that a small fraction of hydrogen was trapped at grain boundaries and dislocations. TEM observations confirmed that hydrogen was trapped at dislocation loops and micro-voids. The implication of the present observation on the determination of diffusion coefficient of hydrogen at low temperatures will be examined and the interaction between hydrogen and dislocation will be discussed in conjunction with mechanical proI?erties of pure iron at low temperatures.

(3:00 p.m.) A STUDY OF DISLOCATION TRANSPORT OF HYDROGEN IN IRON SINGLE CRYSTALS: * C. Hwang and I. M. Bernstein, Carnegie-Mellon Univ. , Dept. of Metallurgical Engineering & Mat. Science, Pittsburgh, PA

The adaptation of laser Raman scattering instrumentation to permit in situ investigation of laboratory-scale magnesium chloride and aluminum chloride cells is described. For magnesium electrolysis the cathode is mild steel and the anode is spectrographic grade ,graphite. For aluminum chloride electrolysis, both cathode and anode are spectrographic grade graphite. Cells operate galvanostatically at current densities up to 500 mA/cm 2 • Magnesium electrolysis was conducted at 740°C in melts containing MgCI2, alkali chlorides, and CaC12 in various proportions. The spatial distribution of MgC14 2- is being: determined. Aluminum chloride electrolysis is presently under study, and the results ~ill be reported in conference.

The dislocation transport of hydrogen during the easy glide strain region in iron single crystals has been studied. In particular, proper combinations of crystal surface orientation and tensile axis were chosen so that resultant hydrogen transport rates associated with edge, screw and mixed types of dislocations could be separately studied. Important functional parameters such as strain rate, lattice hydrogen concentration and temperature were also systematically varied, and their effects on subsequent transport analyzed. Both a qualitative and quantitative description of the hydrogen transport behavior of different dislocation types will be presented .

*The work is sponsored by the U. S. Dept. of Energy under Contract

•This

research has been supported by the Office of Naval Research.

DE-FG07-82 CE4045.

(3:20 p.m.)

ENVIRONMENTAL EFFECTS TMS-AIME General Abstract Session Wednesday, February 27, 1985 2:00 p.m.

Diplomat Sheraton Centre

Session Chairman: C. J. McMahon, Jr., Department of Materials Science and Engineering, University of Pennsylvania LRSM/K1, Walnut Street, Philadelphia, PA 19104

(2:00 p.m.) THE COMBINED EFFECTS OF STRAIN AND HYDROGEN ON THE MICROSTRUCTURE AND HYDROGEN EMBRITTLEMENT OF A-286 IRON-BASE SUPERALLOY: * D.C. Nguyen, I.M. Bernstein and A.W. Thompson, Carnegie-Mellon University, Department of Metallurgical Engineering and Materials Science, Pittsburgh, PA 15213. The role of strain and hydrogen on the loss of coherency of ordered, coherent, y' particles and associated mechanical properties is being studied in the iron-base superalloy, A-286. Specimens were aged in an inert gas or a hydrogen atmosphere to near peak aged and over aged conditions and then deformed to various strains. y' particles were found to remain coherent at low strain (,...1. 5%), even when surrounded by Orowan loops. At higher strains (....... 3%), where more than one slip system is nOw active, the particles can be rendered semi-coherent or incoherent by the combined cutting and looping of dislocations. The effect of dissolved hydrogen is to increase slightly the rate of loss" of coherency of y' particles. The importance of mobile dislocation on the transport of hydrogen in A-286 and subsequent mechanical properties is also being investigated by straining specimens at a slow rate of 1..... 5xlO- 6s - 1 in a cathodic charging environment. *This work is being supported by the Basic Energy Science Division of the Department of Energy.

THE EFFECT OF STRAIN AND THE DISLOCATION TRANSPORT OF HYDROGEN ON DISLOCATION MORPHOLOGIES IN SINGLE CRYSTAL IRON: 'C. Hwang and I.M. Bernstein, Carnegie-Mellon Univ., Dept. of Metallurgical Engineering & Mat. Science, Pittsburgh, PA 15213 Straining permeation tests have been conducted on single crystal iron specimens. Thin foils were then taken from the same specimen from hydrogen free and hydrogen charged regions and studied using transmission electron microscopy. A detailed comparison of the dislocation structures in both clearly showed a strong tendency for particle-associated strain localization, but only in the charged case. The operating slip systems and resulting dislocation structure associated with this strain localization were carefully analyzed and a descriptive model tracing the development of localization will be presented. In addition, evidence linking strain localization to subsequent hydrogen induced crack initiation and embrittlement will be discussed. *This work is being sponsored by the Office of Naval Research.

(3:40 p.m.) STUDY OF HYDROGEN-INDUC.ED STRAIN LOCALIZATION IN 1320 SPHEROIDIZED STEEL:* T.D. Le and I.M. Bernstein, Dept. of Metallurgical Engineering & Materials Science, Carnegie-Mellon Univ. Pittsburgh, PA The straining electrode test (SET), which combines concurrent plastic straining at a low strain rate of about 10- 6 in./sec. with cathodic charging at current density of 2mA/cm2 in O.IN NaOH solution, has been used to investigate the effect of hydrogen on the developed dislocation substructure in spheroidized 1320 steel. Evidence of hydrogen-induced strain localization was found, manifested by a dense dislocation "tail" emanating from carbide particles; this phenomena was not observed in specimen pulled to

82 - TMS-AIME Annual Meeting Program the same strain without hydrogen. The results at a systemat~c study of the strain and hydrogen concentration dependence on the extent and kinetics of strain localization, as well as the effect of localization on the alloy's susceptibility to hydrogen embrit tlement will be discussed. *This research 1s being supported by the Office of Naval Research.

(4:00 p.m.) INTEK;Rl\NUlAR EMBRITILEMENT BY H2 AND Sb IN A Ni-Cr STEEL·. and C. J. McMahon, Jr .. Dept. of Mat. Science and Eng., Univ. of Penna., Philadelphia, PA 19104.

~Morga-",

The canbined effects of hydrogen and impurities in reducing intel:\lranular anbrittlanent were studied in a vacuun-melted 3.5 Ni-1.7 Cr steel doped with Sb. Accoustic anission and SEM observa t ions, coupled wi th At:S measuranents and a finite element stress analysis, were used to determine the critical local stress for fracture of a grain boundary in notched fourpoint bend specimens tested in air and hydrogen gas. Tensile tests of unnotched specimens were also utilized. The results suggest that in both air and hydrogen, brittle fracture in this steel initiates in yrain bcondaries with the largest inclusions and highest Sb concentrations and that the volume of highly stressed material plays an important role. Increased grain boundary concentrations of Sb and hydrogen each had the ef fect of lowering the stresses necessary for nucleation and unstable propagation of the cracks. The results can be inter!.'reted in tenns of the decohesion mechanisn of anbrittlanent. This research is supported by NSF Grant No. DMR-83-11974.

FRACTURE II TMS-AIME General Abstract Session Wednesday, February 27, 1985 2:00 p.m.

Commonwealth Room Sheraton Centre

Session Chairman: R. P. Gangloff, Corporate Research Science Laboratories, Exxon Research & Engineering Co., Route 22 East, Clinton Township, Annandale, NJ 08801

(2:00 p.m.) INCLINED DISLOCATION EMISSION AT A SHIELDED CRACK TIP: S.-J. Chang and S. M. Ohr, Oak Ridge National Laboratory,' Oak Ridge, TN 37S31 Dis 1ocat i on pi 1eup along an inc 1 i ned di rect i on from a crack tip has been observed in metals during tensile deformation in an electron microscope. Dislocations are emitted from the crack tip, move through a dislocation-free zone and pile up in the plastiC zone. Dislocation emission from the crack tip along the inclined direct i on from the crack plane resul t sin blunt i ng of the crack tip. Additional dislocations are emitted from the blunted crack tip. In the present work, the problem of inclined pileup of dislocations at a crack tip with a dislocation-free zone has been so 1ved by app 1yi ng the Wi ener-Hopf method. The resul tis used to arrive at a criterion for the crack tip blunting versus brittle extension. It is also shown that the resistance constant Kg of dislocation emission for the material can be determined by measuri ng the si ze of the di s 1ocat i on-free zone. *Operated by Martin Marietta Energy Systems, Inc. under contract DE-AC05-S40R21400 with the U. S. Department of Energy.

(4:20 p.m.) SOM~ ASPECTS OF ELECTROCHEMICAL MEASUREMENT OF HYDROGEN PERMEATION AND DIFFUSION IN VP IRON AND CARBON STEELS NEAR ROOM TEMPERATURE. J. K. Wu and D. L. Johnson, Dept. of Mech. Engr., Unlv. of Nebr. -::-cTriCOl n, LI nco 1n, NE 68588.

The experimenta 1 technique I nvo 1ves temperature dependent el ectrochemical measurement of hydrogen dlffuslvity and permeability throuqh VP iron and carbon steels between 5-30·C. The measured anodic or permeation current, i , is proportional to unsteady or steady state hydroqen flux o~ the output Sid\Of the membrane. Steady state flux, J~, is linearly related to i c ' The activation enerqy for permeation in VP iron when measured at constant current is 17.7 KJ/mole. The activation energy for permeation at constant fugacity is 36.6 KJ/mole. The latter is in good agreement with the value obtained by extrapolating higher temperature gas phase data to near room temperature. Both diffusivity and permeability decrease as carbon content increases. The activation energy for diffusion increases as carbon content increases. These results are consistent with gas phase measurements obtained at higher temperature. (4:40 p.m.) EFFECT OF HYDROGEN ON SURFACE INSTABILITIES IN SPHEROIDIZED lOgO STEEL: V. B. Rajan and J. P. Hirth, Dept. of Metallurgical Engineering, The Ohio State University, Columbus, Ohio 43210 U notched bend specimens of spheroidized 1090 steel have been deformed in tension and compression to st~y the effect of hydrogen on the evolution of surface instabilities. The onset of these instabilities has been found to agree fairly well with continuum mechanics predictions. Hydrogen has been found to enhance the onset of the instabilities. The relevance of these results in the study of hydrogen embrittlement will be di scussed.

(5:00 p.m.) THE INTERACTION OF HYDROGEN PERMEATION AND DEFORMATION IN POLYAND SINGLE CRYSTAL NICKEL: G. S. Frankel and R. M. Latanision, The H. H. Uhlig Corrosion Laboratory, Massachusetts Institute of Techno logy, Cambri dge, MA 02139. The electrochemical permeation technique was used to investigate the effects of deformation on steady state fluxes of hydrogen in nickel. For polycrystalline nickel 270, a strong dynamic trapping effect was found to dominate any dislocation transport phenomenon. At slow strain rates, lattice refilling will mask the trapping effect and increases in the input hydrogen concentration due to plastic deformation at the surface will increase the hydrogen flux. For single crystal nickel, dynamic trapping is minimized and the hydrogen flux increases in the easy glide region. This may be due to dislocation transport. The extent of easy gl ide was larger for specimens charged with hydrogen, indicating an effect of hydrogen on dislocation motion.

(2:20 p.m.) TEM STUDIES OF LOW TEMPERATURE FRACTURE IN MOLYBOENUM·: C. G. Park and S. M. Ohr, Oak Ridge National Laboratory, Oak Ridge, 'i'N37B31 The nucleation and propagation of cracks in molybdenum have been studied during in situ tensile deformation in an electron microscope at temperatures as low as -IS0°C. The temperature dependence of crack tip deformation, as well as the distribution of dislocations ahead of the cracks, has been examined. As the test temperature wa s lowered, the extent of crack ti p deformat ion decreased while the emission of screw dislocations from grain boundaries increased. A rapid transgranular brittle crack extension without plastic deformation was observed at temperatures below -135°C. The ducti le-brittle transition of the fracture mode observed in the electron mi croscope was in good agreement with the mechanical behavior of the metal observed from the bulk tensile tests performed at low temperatures. *Research sponsored by Division of Materials Sciences, U. S. Department of Energy under contract DE-AC05-S40R21400 wi th Martin Marietta Energy Systems, Inc.

(2:40 p.m.) INTERPRETATION OF FRACTIJRE MECHANISMS IN A AL-4'101 ALWY BY QJANTITATIVE FRACf(X;RAI'HY:* K. Banerji and Ervin E. Underwood, Fracture and Fatigue Research LabOratory, Georgia Institute of Technology, Atlanta, Georgia 30332-0102. Fracture mechanisms in a coarse grained Al-47oCu binary alloy were studied using quantitative fractographic methods. Specimens with different precipitate rrorphology, size and distribution obtained by aging treatments were fractured at roan temperature urrler tensile conditions. The fracture in all cases was of a 450 shear type. Qualitative observations of SEM pictures did not reveal any definitive differences between the fracture surfaces. However, analysis of digitized fracture surface profiles obtained by serial sectioning showed significant rn.rnerical differences as a hmction of the aged microstructures. Comparison of corrputed profile and surface parameters indicated contribution of the aging process to the attributes of the fracture surfaces. The efficacy of these quantitative methods in fracture research was denonstrated. The application of the procedures in the study of fatigue fractures is also discussed. * This work was supported by NSF Grant No. DMR-8204018

(3:00 p.m.) STATISTICAL ASPECTS OF CLEAVAGE CRACKING IN MILD STEEL:· Tsann Lin and R. O. Ritchie, Department of Materials Science and Mi nera 1 Engi neeri ng and Lawrence Berke 1ey Labora tory, Uni vers i ty of California, Berkeley, CA 94720. Experimental studies on low temperature transgranular cleavage in an AISI 100S steel are presented, involving microstructures where grain size and carbide size are independently varied. Results are analyzed in terms of a weakest link cleavage cracking model, representing a modification to that proposed recently by Evans in order to predict the critical distance from the crack tip where the initial cracking event is most probable. The model, which is valid where the critical step is the propagation of grain boundary carbide cracks into the ferritic matrix, is discussed in terms of

TMS-AIME Annual Meeting Program - 83 detailed microstructural examination, specifically involving a statistical analysis of the cracked carbides in the active volume at the crack ti p. *Sponsored by the Office of Basic Energy Sciences of the U.S. Department of Energy.

(3:20 p.m.) INFLUENCE OF COMPRESSION OVERLOADS ON THE THRESHOLD CONDITION FOR FATIGUE CRACK GROWTH:* E. Zaiken, Shiley Incorporated, Irvine, CA 92714 and R. O. Ritchie, University of California, Berkeley, CA 94720. A study has been made of the effect on single compression overload cycles on long fatigue cracks arrested at the threshold IlKTH in underaged, peak aged and averaged microstructures in 11M 7150 aluminum alloy. Compression cycles, of the order of 5 times the maximum tensile loads, were observed to cause immediate reinitiation of crack growth at IlKTH, consistent with a measured reduction in crack closure. Subsequent crack growth was observed to decelerate progressively until re-arrest, consistent with a measured re-development of closure. Results are discussed in terms of the microstructural origins of crack closure in precipitation hardened alloys. *Sponsored by the Air Force Office of Scientific Research.

(3:40 p.m.) COEXISTANCE OF BRITTLE AND DUCTILE FRACTURE IN BCC fIETALS: S. M. Ohr, S.-J. Chang, C. G. Park, Oak Ridge Nat'!. Lab.*, Oak Ridge, 'fNand R. Thomson, Nat'l. Bureau of Standards, Washington, DC It is well established that at low temperatures bcc metals fail by cleavage which is preceded by crack tip deformation. Recent electron mi croscope studi es, showi ng that crack propagation in bce meta lsi s a mi xed mode process, have prompted us to exami ne the coex i stance of bri tt 1e and duct i I e fracture under mi xed mode loading conditions. It is found 'that the dislocations emitted under modes II and III do not shi e I d the crack ti p from the mode lapp lied stress intens i ty factor. Thus, when a crack is loaded ina mi xed mode, crack ti p deformati on may occur in ei ther mode II or III, while the mode I stress intensity factor simultaneously increases to the critical value for cleavage. This new mechanism is' compared with the one recently proposed by Sinclair and Finnis. *Operated by Mart in Mari etta Energy Systems, Inc. under contract DE-AC05-840R21400 with the U. S. Department of Energy.

(4:40 p.m.) DYNAMIC FRACTURE TOUGHNESS CHARACTERISTICS OF 02 TOOL STEEL: T. M. Breunig, FMC Corp., Fridley, MN and F. J. Worzala, UniversitY of Wi scons in, Madi son, WI. The influence of heat treatment on the dynamic fracture toughness characteristics of 02 tool steel was studied by use of the instrumented impact test. The optimum heat treatment was found to be an austemper process which used an austenitizing temperature of 1850°F, and an isothermal transformation temperature of 600°F. The microstructure produced was tempered martensite, retained austenite, alloy carbides, and bainite. The dynamic fracture toughness obtained was 17 ksi lin. When higher than conventional austenitizing temperatures were used, the austenite stabil ity increased and grain boundaries were de 1 i neated by ca rbi des and i mpu ri ty elements. The i nfl uence of mi crostructura 1 const i tuents on toughness is di scussed.

(5:00 p.m.) MICROSTRUCTURAL EFFECTS ON THE LOW CYCLE FATIGUE BEHAVIOR OF A HIP'd NICKEL BASE SUPERALLOY:* J. S. Crompton, R. S. Vecchio and

R. v!. Hertzberg, Dept. of Metallurgy & Materials Engineering, Lehigh University, Bethlehem, PA 18015. The influence of microstructure on the fatigue response of materials has long been opeI,l to speculation. The effects of variables such as grain size and second phase particle distribution may lead to complex interactions. The present work has sought to clarify the behavior in a hot isostatically pressed nickel base superalloy. HIP'd L.C. Astroloy possessing average grain sizes differing by an order of magnitude and having known second phase particle distributions have been tested using standard low cycle fatigue tests. In addition to the determination of mechanical property data, the development of microstructural damage has been observed using standard TEM procedures. The results are presente<;l in terms of the influences of microstructure on the low cycle fatigue behavior, the fatigue crack growth response and the dislocation substructure of the material. *This research was supported under AFOSR grant number 83-0029.

HERBERT H. KELLOGG SYMPOSIUM: Iron and Steel Sponsored by The Physical Chemistry Committee and The Copper, Nickel, Cobalt and Precious Metals Committee Wednesday, February 27, 1985 2:00 p.pt.

Regency Ballroom Sheraton Centre

Session Chairmen: W. L. Worrell, University of Pennsylvania, Philadelphia, PA 19104; M. C. Jha, AMAX Extractive R&D, Inc., 5950 McIntyre St., Golden, CO 80403

(4:00 p.m.) AN INTERPRETATION OF THE FRACTURE STRAIN AND CRARACTERISTIC FRACTURE DISTANCE: *- W.M. Garrison, Jr., Department of Metallurgical Engineering and Materials Science, Carnegie-Mellon University, PittSburgh, PA 15213. In the characteristic distance model for ductile fracture the fracture 20ughness is proportional to {E~ ~~OyE'}~ where E'=E/ (I-\! ), 0y is the yield strength, £.~ is the critical fracture distance and is the fracture strain. For ultra high s~rength steels the fracture toughness is proportional to {Xo I30 y E'} where Xo is the average sulphide spacing and f3 is a parameter characterizing the extent of g~owth of voi~s nUct=~ted at the sulphicles. I t is proposed that
Ef

£t

*This work is supported by the U.S. Department of Energy under contract number DE-AC04-76DP00789.

(4:20 p.m.)

(2:00 p.m.) CHARl\CI'ERIZATION AND UTILIZATION OF I1UHlEARING STEEL PLIINT WllSTE MATERIAIS: D. R. Fosnacht, Inlani Steel Co., Research Iab:Jratories, East diicago, Iniiana 46312.

An investigation was initiated to obtain the scope of the probl""", associated with recycling the various waste oxide rraterials generated at Inlani ani to identify and test possible teclmiques that could possibly aid in increasing the aITIOlll1t of waste oxide naterials recycled to primary operations. Based on the results of this work, several new teclmiques were developed ani tested either on a plant or pilot scale. These include the use of cold-bani agglareration rrethcx:ls for prcx:lucing waste oxide agglanerates for use as cooling agents or scrap substitutes in steellnaking operations, ani the use of various teclmiques for upgrading blast furnace flue dust and soaking pit scale so that the upgraded rraterials can be utilized in sinter plant or ironmaking operations. The physical and chemical characteristics of the waste oxide rraterials and the results of the pilot scale ani plant testing will be discussed in this paper.

THE INFLUENCE OF MICROSTRUCTURE AND ENVIRONMENT IN THE GROWTH OF SMALL FATIGUE CRACKS*: J. Lankford, Southwest Research Institute, San Antonio, TX The growth of large and small fatigue cracks in a preci pitati on-hardened a 1 umi num alloy has been characteri zed for air, dry nitrogen, and vacuum environments. Precipitate microstructure has ileen varied, and its effect upon crack growth in air established. It is found that"environment and microstructure alter both crack growth rate and crack growth mode, especially for sma 11 cracks, whi ch tend to grow fas ter than, and below the threshold stress intensity for, large cracks. Striation spacing measurements, and use of an SEM cyclic loading stage to characteri ze crack tip deformati on and mi cromechan i cs, provi de ins i ght regarding some of the fundamental processes responsible for the observed crack growth trends. *Research supported by the U.S. Army Research Office.

(2:30 p.m.) CONTINUOUS CASTING OF STEEL. Robert D. Pehlke, The University of Michigan, Ann Arbor, Mlchlgan. The history of continuous casting is reviewed and accelerated implementation occurring in the steel industry is described. A general description of the process is presented. Elements of machine component design are outlined and key steps in integration into a casting system are detailed. Start-up experiences are characterized. Operating strategies for continuous casting of steel are summarized. Recent developments are reviewed and future developments for this technology are considered.

84 - TMS-AIME Annual Meeting Program (3: 00 p. m. ) DIRECT !1ETHOD TO PREPARE LOI, CARBON FERROCHROME: S. E. Khalafalla and J .E.Phalman, Bureau of Mines, Minneapolis. MN A method for preparing ferrochromium alloys containing less than ~ pet carbon has been devised in a single vacuum furnace reactor. This met hod cao conserve chromium and reduce the capital and energy requirements relative to chromite electrothermal reduction. Reduced products containing less than 2 and as low as 0.01 wt pet carbon were obtained by reacting pellets of chromite and carbonaceous reductant at pressures of 0.1 to 1 torr and temperatures of 1,230° to 1,320° C. Foundry coke, anthracite, and carbon black ",'ere found to be superior to graphite as reductants. The reduc-

ion of chromite to metallics was found to proceed via the carbide intermediates (Fe, Cr)7C3 and (Fe, Cr)23C6, with no evidence of the intermediates Fe3C or Cr3C2' Lime accelerates the rate of solid-state reduction of chromite and can shorten the furnacing time at 1,300 0 C under vacuum from 13 hours to less than 3 hours. Additional lime and silica are added to the hot reduced chromite after releasing the vacuum and raising the furnace temperature to 1,700 0 C. Soaking the charge for about 20 minutes gave a button of low carbon ferrochromium alloy beneath a well-defined slag layer.

HYDROMETALLURGY/CHEMICAL PROCESSING IV Sponsored by the Joint TMSISME A/ME HydrometallurgylChemical Processing Committee Wednesday, February 27, 1985 2:00 p.m.

Senate Suite Sheraton Centre

Session Chairpersons: Barbara Krebs, Atlantic Richfield, 515 South Flower St., Los Angeles, CA 90071; Sanaa E. Khalafalla, U.s. Bureau of Mines, 5629 Minnehaha Avenue South, Minneapolis, MN 55417

t

(3: 30 p.m.) TURBULENCE PHENOHEtJI\ IN METALS PROCESSING: Julian Szekely, Department of Mat. Sci. & Eng., Massachusetts Instltute of Technology, Cambridge, MA 02139. There are many metals extraction and refining processes which involve melts undergoing turbulent motion. Steelmaking, vacuum degassing, electric smelting, electric arc furnace operation and induction furnaces may be regarded as representative examples. A general formulation is presented, describing these systems in terms of the turbulent Navier-Stokes equations, the differential thermal energy balance equation and the convective mass transfer equation. Through the numerical solution of these, some general relationships are developed. The specific systems considered include induction furnaces, electric resistance heated systems and gas bubble driven circulation systems.

(4:00 p.m.) CARBOTH ERM I C RE DUCT I ON OF MINE RALS I NAP LASMA ENV IRONMENT:

J.J. Moore, M.M. Murawa, K.J. Reid, Mineral Resources Research Center, University of Minnesota, Minneapolis, MN. The interaction of mineral and carbon particles within a plasma medium is discussed with particular emphasis on the type of plasma required for such reactions and the satisfactory introduction of such particles into the plasma medium. The results of laboratory-scale experiments for the carbothermic reduction of chromite, taconite and chalcopyrite within a plasma environment are presented and the application, advantages and limitations of effecting such reactions in pyrometal1urgical processes are discussed.

(2:00 p.m.)

"A STUDY OF COBALT EXTRACTANTS IN THE SEPARATION OF COBALT AND NICKEL FROM SULFATE SOLUTIONS", Eddie C. Chou, Leo W. Beckstead, and John D. Bruno, AMAX Extractive R&D, Inc., Golden, CO 80403 Recently developed cobalt extractants (B-diketone from Hinkel, alkyl phosphoni c compound fro," Da i hachi , and alkyl phosphi ni c compound from Cyanamid) for the separation of cobalt and nickel in sulfate solutions have been investigated. Concerning organic stability, selectivity of cobalt extraction, and impurity di s tri but i on, a compa ra ti ve study of these two phosphorus extractants with the well establ ished cobalt extractant, di(2-ethylhexyl) phosphoric acid (D2EHPA), is reported. t1ethods for ",aximizing the separation of cobalt and nickel, minimizing cobalt recycle from scrubbing to extraction stages, and preventing the scaling of calcium sulfate are also discussed.

(2:25 p.m.) A SIMPLIFIED SCHEME FOR THE RECOVERY OF COBALT IN CARON TYPE NICKEL PLANTS: F. G. Prado, B. W. Wiegers and J. P. Dempsey, NiCobalt International Corporation, P.O. Box 5560, Lakeland, FL

33807-5560. The Caron process for nickel from laterites also extracts cobalt. Nicaro depressed cobalt to achieve product specifications, 'With a nickel loss. Yabu1u and Nonoc enhance cobalt extraction and remove it as a sulfide before nickel precipitation. That also removes nickel (3 times the cobalt). All Caron plants process nickel through basic nickel carbonate CBNC). Nicaro and Yabulu calcine BNC to nickel oxide. Additional Steps are required for higher grades. Nonoc dissolves BNC in a recycled ammonium sulfate solution and produces nickel powder by hydrogen reduction. Cobalt. if not removed as a sulfide, reports in BNC and ammonium sulfate solution. Nickel is selectively precipitated by hydrogen to Ni/Co>lOOO. Cobalt is recovered as an anunonium double salt with Co/Ni>l. The scheme provides substantial capital and energy savings compared with current practices.

(2:50 p.m.) EXTRACTION EQUILIBRIA IN THE SYSTEM GaC1 3-A1C1 3 -HC1-H 2 {}TRIBUTYL PHOSPHATE AND A CHEMICAL THERMODYNAMIC MODEL TO PREDICT THE SOLVENT EXTRACTION OF GALLIUM: Ve8a~Pekka Judin and Renato G. Bautista, Ames Laboratory USDOE and Dept. of Chemical Engineering, Iowa State University, Ames, Iowa 50011. Partition equilibria and solution chemistry of the system

GaC1 3-AIC1 3-HCI-H 2 (}-Tributyl phosphate have been studied. (4:30 p.m.) A SOLID-STATE EMF STUDY OF THE Fe-Ni-S-O QUATERNARY SYSTEM: Ker-Chang Hsieh and Y. Austin Chang, Dept. of Metallurgical and Mineral Engrg .. University of WIsconsin, 1509 University Ave., Madison, WI 53706. Four three-phase equil ibria and one two-phase equil ibrium in the Fe-Ni-S-O quaternary system in the vicinity of 1023 K and ps02 atm were studied using the following emf cell Pt,02(air) Izr02.CaOlpso = 1 atm, mixture of phases, Au 2 The four three-phase equilibria are sp + (Fe,NilS + Ni 3 S2 , sp + Ni 3S2 + Ni 0, sp + Ni + Ni S04 and Fel03 + sp + (Fe, Nil S04' The two-phase equilibrium is sp + (Fe,NilS. The two-phase equilibrium was measured by using mixtures containing a major portion of one phase and a mi nor portion of the other. The resu1 ts are presented in terms of oxygen potential as a function of YNi = nNi/(nNi+nFe) at constant te~erature and p 02 = 1 atm. The stability diagram was also calculated using appropria te thermodynami c model s for all the pertinent phases. The calculated diagram is in accord with the measured ones.

The

system is characterized by a simultaneous extraction of gallium chloride, hydrochloric acid, and water by a solvating mechanism. The salting-out power of the aqueous phase was successfully interpreted by considering the stability of aluminum chloride and gallium chloride complex species and calculating the concentration of free chloride ions actually available for the extraction of gallium. Three gallium extraction mechanisms in the range of compositons examined include e traction of GaC1 3 at low Wand salt concentrations, extraction of GaCl- lJ. at moderate W- and salt concentrations, and the competition ot GaCl- 1t with a HCI-TBP complex at high Wand salt concentrations.

°

(3:30 p.m.) PRECIPITATION STRIPPING OF IRON-LOADED CATION EXCHANGE EXTRACTANTS F .M. Doyle-Garner, University of California, Berkeley, CA, A.J. Monhemius, Imperial College of Science and Technology, London, England. Precipitation stripping is a single-stage process whereby iron is stripped by dilute mineral acid from a loaded cation exchanger, hydrolysed and precipitated at about 100oC. The reactions occurring, which are represented as:

(RCOO) 3Fe (org) + 3H+ (aq) stripp\ng Fe 3+ (aq) + 3RCOOH (org) hyd~is FeOOH(s)+ 3H+(a ) show th~t the pro~ess is self-sustaining1 the min~ral acid is merely an intermediate medium for iron, and PH. is buffered by the cation exchanger. With seeding, 90% of the iron was stripped from a 209/1 Fe(III) carboxylate solution by 209/1 H2S04 within 33mins.

Fe 3+(a )+ 2H20(a )

TMS-AIME Annual Meeting Program - 85 The rate decreased with no seeding, decreasing acid and [Fe (III)] and when (NH4) 25°4 was present. Final concentrations approached O.OSg/l Fe(III)org' "FeCOH, Fe4S04(OHlJO or jarosite precipitated from H2S04 systems, and aFe203 precipitated from Hel and HN03 systems. No precipitation stripping occurred with iron-loaded D2EHPA. The observed behaviour is discussed in relation to the literature on the solution chemistry and hydrolysis of iron.

(3:55 p.m.) "PRECIPITATION OF r10LYBDEtIUM SULFIDE FRat1 AQUEOUS SOLUTION", Leo W. Beckstead, Dale K. Huggins, and Eddie C. Chou, Ar1AX Extractive R&D, Inc., 5950 McIntyre Street, Golden, CO 80403 Although precipitation of molybdenum as the sulfide is one of the oldest methods for recovery of molybdenum, the chemistry of the precipitation reaction is still not understood. In particular, the electronic state of the molybdenum in the sulfide precipitate is the subject of debate, and disagreement exists over which factors control complete precipitation. Re-evaluation of the state of knowledge in the light of more recent theoretical and practical findings has led to the development of a method for precipitating molybdenum sulfide which is effective on a wide variety of solutions, and is applicable not only for purification of sol uti ons, but a 1so as a primary method for molybdenum recovery. The key to the method is to add the sulfide reagent at a pH which is high enough to avoid precipitation of molybdenum sulfide, then to very rapidly acidify the solution to pH of about 2.5, \·,here molybdenum sulfide precipitates. An explanation of the advantage of rapid acidification in terms of the present understanding of the chemistry of molybdenum sulfides is presented, and the effects of process variables are discussed.

LEAD, ZINC, TIN II: TIN METALLURGY Sponsored by the TMS Lead, Zinc, Tin Committee Wednesday, February 27, 1985 2:00 p.m.

Princess Bal)room Sheraton Centre

Session Chairman: P. Halsall, Capper Pass Ltd., North Ferriby, North Humberside, HU14 3HD, England

(2:00 p.m.) TIN PROCESSING AT THE TEXAS CITY SMELTER: E. B. King, D. N. Gibson, Gulf Chemical & Metallurgical Company, Texas City, TX A general description of the Gulf Chemical and Metall\1rgical Company Texas City T;l.n Smelter is presented describing changes in the original smelting process to convert from a primary tin smelter to a flexible primary and secondary tin and tin/lead smelter. The paper covers the change from reverbatory to High Speed Rotary Converter Furnace smelting, the ability to process any grade of tin or lead bearing materials from high grade tin concentrates to low grade tin/lead secondaries, and the electrolytic refining to either Grade A tin or Electrolytic Solder Metal. Emphasis is given to High Speed Rotary Converter Fur-_ nace operations and major maintenance, raw material size and grade flexibility, and water and flue gas effluent control. .

(2:20 p.m.) TIN SMELTING IN MALAYSIA - AN UPDATE: J. Armstrong, Malaysia Smelting Corporation Sdn. Bhd., Butterworth, Malaysia. The history of tin smelting in Malaysia was described in a previous paper presented at the Fourth World Tin Conference in Kuala Lumpur in 1974 and included a description of the then current operations at the two Penang smelters. The present paper notes the changing problems facing a Malaysian smel ter and the approach to these problems as well as the structural changes in the Malaysian tin industry that have resul ted in the formation of the Malaysia Smelting Corporation.

(3:00 p.m.) THE SECONDARY TIN INDUSTRY: C.M. Stott, B.Sc., A.C.M.A., Capper Pass Limited, North Ferriby, N.Humberside, HU14 3HD The paper compares the levels of recycling of some of the major non-ferrous metals and highlights the apparently poor performance of the tin industry in this field. The properties of tin, its uses and the resultant impact on the recycling of the metal are discussed. The main industrial processes associated wi th the recovery of tin from secondary sources are briefly describedj in particular the detinning of tinplate scrap, tpe treatment of tin/lead combinations, the treatment of tin/copper combinations and the treatment of complex materials to yield high grade tin metal.

(3:20 p.m.) SILVER REMOVAL FROM METALLIC TIN: L. W. Pommier G. General Manager and L. Sivila S. Operations Manager, E.N.A.F., Oruro, Bolivia. During the tin smelting process of the Bolivian Vinto Smelter, crude tin with up to 0.2% Ag is prepared for the separation of silver. Two methods are studied; Electrolysis where Ag reports to anode slime, and a thermal system applying a modified Parkes process by intermetallic precipitation with zinc. The basis of the Parkes process is defined and the practical resul ts are presented. It is snown that two types of Ag residUes are obtained, one at 0.5% Ag, 83% Sn, which is treated in a second stage giving a product 2.2% Ag, 81.5% Sn.

(3:40 p.m.) THE TREATMENT OF LOW-GRADE CONCENTRATES IN THE VlNTO BOloIVIAN SMELTER: L. W. Pommier G. General Manager, L. Sivila S. Operations Manager, E.N.A.F., Oruro, Bolivia. The low grade tin smelter of the Vinto plant was built to process concentrates wi th an average grade of 25% Sn and oxides containing 50% Sn produceq in La Palca volatilization plant. These oxides contain up to 25% Sb, As, Pb, Zn and Ag combined, are difficult to separate. The original design included vacuum refining furnaces to extract Pb & B1; Sb and Zn are removed by thermal means. The paper also presents al ternative methods to &eparate silver and produce marketable tin.

MECHANICAL PROPERTIES III TMS-AIME General Abstract Session Wednesday, February 27, 1985 2:00 p.m.

Georgian Ballroom A. Sheraton Centre

Session Chairman: W. M~ Garrison, Jr., Carnegie-Mellon University, Pittsburgh, PA' 15213

(2:00 p.m.) HIGH TEMPERATURE CRACK GROWTH IN A DIRECTIONALLY SOLIDIFIED NICKEL BASE SUPERALLOY: K. Sadananda and P. Shahinian, Code 6393, Naval Research Laboratory, Washington, DC 20375 High temperature crack growth behavior of a directionally solidified nickel base superalloy has been determined under cyclic, static and combined loads as a function of load amplitude, temperature and environment. The data were analyzed using both linear and. non-linear elastic fracture mechanics methods. Detailed metallographic and fractographic analyses have been made to determine the Dlicromechanisms of crack grQwth. The results are discussed in terms of the cumulative damage tIIOdels.

(2:20 p.m.) (2:40 p.m.) SMALL ELECTRIC FURNACES IN TIN SMELTING: R.F .Price, W.D.Pullman, Base Metal Synergy Associates, North Cave, Brough, North Humberside, England. Electric furnaces offer several advantages over both the reverberatory and rotary furnaces for tin smel ting and, al though large smel ters have only recently introduced them, several small tin producers have smelted this way for many years. The various types of electric furnaces used in these plants are described and their merits are discussed. Small electric furnaces, if designed correctly, can be relatively simple and cheap to install. The important design para!'l1eters are listed and the construction of a typical submerged arc electric furnace is described. A wide range of raw materials can be treated if pre-treatment is employed and the use of several small furnace units permits flexibili ty of the smelter flow sheet. Metallurgical factors and general operating parameters are discussed. Details of capital and operating costs are given which demonstrate the economic advantages of the use of small electric furnaces in tin smelting.

SOLUTE STRENGTHENING AND PRECIPITATION KINETICS OF AlN IN Mo HSLA STEELS: D. Anderson and M.G. Akben, McGill University, Montreal, Quebec. The effect of Al and N addition on the high temperature flow behaviour of a series of four 0.07% C, 1.25% Mn and 0.20% Si steels was investigated. A plain carbon and a 0.20% Me steel were tested as reference materials. To the latter, 0.08% Al was added with 0.005 and .0.010% N. The influence of (i) Al and Mo in solid solution and (ii) AIN precipitation on the dynamic recrystallization kinetics was studied. To dis'tinguish these effects, compression tests were carried out in the temperature range 875 to 925°C at constant strain rates varying from 5 x 10- 5 to 5 X 10- 1 S-I. The precipitation kinetics of AIN at the two levels were determined from the mechanical test data. and are compared to those reported in the literature. The presence of Me delays the onset of precipitation. This is attributed· to the increased solubility of AIN in austenite due to the decrease in the activity coefficients N and probably Al as well. The recrystallization retarding effects of Al and Me in solution are about equal (per 0.1 at. %) when added alone. They are less effective than Nb and Ti, but more than V. When Al and Me are added jointly, there is a synersistic effect, possible explanations of which are discussed.

86 - TMS-AIME Annual Meeting Program (2:40 p.m.) PROPERTIES AND MICROSTRUCTURES fOR DUAL ALLOY COMBINATIONS OP THREE SUPERALLOYS \!lITH ALLOY 901; Fredri c H. Harf, NASA Lewi s Research Center, C1 eve 1and, OH 44135. Dual alloy combinations are under consideration for parts such as turbine disks where different stress and temperature regimes exist during operation. Such combinations may also result in the conservation of elements which are costly or not mined domestically. Preferably single heat treatment yie1 ding good properties for both alloys should be used. Dual alloy combinations of iron rich supera110y 901 with nickel-base superalloys Rene 95, Udimet 700, or MERL 76 were hot isostatically pressed from prealloyed powders. Individual alloys, mixtures, and layered combinations were given the heat treatments specified for use in turbine disks or apP.ropriate for alloy 901. Selected specimens were overaged for 1500 hours at 6500 C. Metallographic examinations revealed no phases not originally present in either alloy of a combination. Mechanical tests showed adequate properties in all superalloys with the alloy 901 heat treatment. The results indicate that these comBinations are promising for use In turbine disks. (3:00 p.m.) CCMBlNED EFFECT OF SULFUR AND HYDROGEN ON TIlE GRAIN BOUNDARY STRENGTIl OF IRON: K.S. Shin, Arizona State University, Tempe, AZ 85287 and M. Meshli, Northwestern University, Evanston, IL 60201 The intergranular fracture stress of iron was examined as a function of grain boundary concentration of sulfur and hydrogen. It was found that the effect of sulfur was reversible whereas hydrogen could have two different effects, reversible and permanent, on the intergranular fracture stress. Empirical equations were obtained for the intergranular fracture stress as a function of grain boundary concentration of sulfur and hydrogen which show little evidence of synergistic effect of sulfur and hydrogen on the grain boundary strength of iron. The pemanent effect of hydrogen was found to be caused by the generation of intergranular microcracks due to precipitation of molecular hydrogen and was analyzed using a modified Griffith equation. The predicted sizes of microcracks from the equation were compared with microcracks determined metallographically. Mechanicsms of intergranular fracture and the combined effect of sulfur and hydrogen on the grain boundary strength of iron will be discussed in the light of these observations. (3:20 p.m.) ON THE INITIATION OF FATIGUE CRACKS IN ENGINEERING PLASTICS:*

J.t. Turkanis, R.I·LHertzberg and J. A. Manson, Dept. of Metallurgy and Materials Engineering, Lehigh University. Bethlehem, PA 18015 Previous studies have shown that the fatigue crack propagation resistance of PVC is enhanced by the addition of rubber particles while others have shown a reduction in the total life when a rubbery phase is added to polystyrene. The objective of this study was to examine di fferences in the relative importance of the initiation stage in sets of neat and rubber-modified PVC samples of varying molecular weight. To accomplish this, the number of cycles necessary to initiate a crack 0.25 nun in length from a polished notch in a 4-pt. bend-specimen, was compared as a function of the load notch root stress level. In marked contrast to the FCP results, it was seen that the fatigue initiation lives in PVC decreased when the MBS phase was added. Total life calculations based on both crack initiation and propagation data are compared.

*This work was supported by the polymers program of NSF under

grant No. DMR-8106489.

(3:40 p.m.) SUPERPLASTI CAl ALLOYS: J. IJadsworth, Lockheed Palo Alto Research Laboratories, 3251 Hanover St., Palo Alto, CA 94304. The development of superplasticity in A1 alloys will be discussed. In particular, emphasis will be placed on superp1astic properties that have been developed in Al-Li based alloys. Alloys produced both by ingot metallurgy (1M) and powder metallurgy (PM) are included. The influences of processing parameters leading to superp1asticity are discussed and the properties of Al-Li alloys produced by rapid solidification processes are also described. Mi crostructura 1 changes that occur as a result of thennomechanica 1 process i ng are presented.

where 6K is the stress Intensity range and E Is Young's modulus. The values of 6
MICROSTRUCTURAL CONTROL DURING ALUMINUM ALLOY PROCESSING II: Deformation, Recovery and Recrystallization Sponsored by: TMS Non-Ferrous Metals Commit(ee Wednesday, February 27, 1985 2:00 p.m.

Monarch Sheraton Centre

Session Chairmen: E. H. Chiao Southwire Company. P.O. Box 1000, Carrollton. GA 30119; H. J. McQueen, Concordia University, Montreal P.Q. H3G 1MB, Canada

(2:00 p.m.) "STRUCTURAL FEATURES OF' THE ALUMINUM ALLOY EXTRUSION PROCESS", T. J. Sheppard, Imperial College, London, England. The effects of homogenization and preheat treatments are discussed. The development of substructure within the extrusion chamber is described and the phenomenon of break-through pressure analyzed. The relationships between processing parameters, structure and properties are presented and it is shown that these may influence properties after prolonged heat treatments. (2:25 p.m.) "INFLUENCE OF HIGH STRAIN ON THE SUBSTRUCTURE OF ALUNI NUM " , H.J. McQueen*, Mechanical Eng., Concordia Univ., Montreal, PQ 113G1MB, Canada, O. Knustad, N. Ryum, J.K. Solberg, ' Physical Metallurgy Inst., Norwegion Inst. of Tech., N 7034 Trondheim-NTH, Norway. 'lbrsional defm:mation at 400°C and 0.2s- l was conducted on Al with 0.1 and 2rrm grains to equivalent strains of 1,3,10,20,40, and 60. lhe grain and subgrain structures were examined by polarized light microscopy and '!'EM on tangential sections. 'Ihe initially equiaxed surface grains wound into spirals so that their axial spacing varied inversely as the strain. Equiaxed subgrnins of 7 lJIll persisted throughout straining fran 1 to 60, causing the grain bo\mlaries tobecare strongly serrated. 'Ihe 0.1 or 2rrm grains lost their distinctness at about 20 or 60 as they becarre as thin as sut:>gYains. A preferred orientation developed with <110> parallel to a tangent and <111> and <110> parallel to the axis, but becaning <112> at high E. lhe mi=structure of crystallites with mixed 10M and high misorientations results fran subgrain formation, boundary migration into serrations, severe reduction in grain d:irrension, and grain rotation into a ccmron orientation. With 00 long range migration of <;Jl'ain boundaries, or continued grcwth of subgrain misorientation, this 1.8 not ordinaIy discx:mtinoous, or continuous, dynamic recrystallization. (*M:lch. Eng_, Cbncordia Univ .. Montreal) (2:50 p.m.)

(4:00 p.m.) MEASUREMENTS OF STRAINS NEAR A GROWING FATIGUE CRACK TIP: P. K. liaw, Metallurgy Department, Westinghouse R&D Center, Pittsburgh, PA 15235 In a mode I propagating fatigue crack an empirical relationship between the horizontal distance X from the crack tip and the strain range 6
(2.63(mean) 10-1

±

0.97 (standard deviation)} x

M X-O.54 (mean)±0.06(standard deviation) E

THERMOMECHANICAL PROCESSING OF ALUMINUM ALLOYS FOR GRAIN SIZE CONTROL, John A. Wert, Rockwell Internat i ona 1 Sc i ence Center, Thousand Oaks, CA 91360 Thennomechanical processing of aluminum alloys can lead to room temperature strength increases, and to superplastic behavior during elevated temperature d~formation. Control of recrystallization processes by particle dispersions is a key element in achieving the fine grain sizes needed to obtain the desired properties. Two distinct recrystallization paths are available to re1 ax the stored energy of deformation. Oiscontinuous recrystall ization proceeds via nucleation and growth of new grains. Experiments have shown that a bimodal particle dispersion provides the greatest extent of grain refinement by discontinuous

TMS-AIME Annual Meeting Program - 87 recrystallization. Continuous recrystall ization, an extension of recovery, occurs when the more rapi d d i scont i nuous process i ~ suppressed by a dispersion of small particles. Thermomechanlcal processes designed to provide grain size control by these recrystallization mechanisms will be discussed. (Supported by Rockwell International Research & Development Funds)

Wednesday, February 27, 1985 2:00 p.m.

(3: 15 p.m.) THE CONTROL OF THE MICROSTRUCTURE OF ALLOYS BY PROCESSING, 1. H. Sanders, Engineering, Purdue University, West E. A. Starke, Jr., Materials Science of Charlottesville, VA 22901.

HIGH STRENGTH ALUMINUM Jr., School of Materials Lafayette, IN 47907, and and Engineering, University

This paper will present an overview of the processing techniques applied to the new generation of high strength aluminum powder metallurgy (P/M) alloy, and aluminum-lithium alloys. The relationships between alloy chemistry, processing history and fracture critical parameters will be presented for these alloys. For the PIM alloys the nature of the oxide film and its distribution and the size and distribution of second phase particles have been shown to i nfl uence mechani cal properties. Consequently, an important aspect of PIM alloys is the relationship between processing temperature, deformation, particle distribution and properties. The new aluminum-lithium alloys contain zirconium to control grain morphology and degree of recrystallization. The mechanical behavior of these alloys tend to be strongly affected by crystallographic texture. The relationship between processing va ri ab 1es, texture and propert i es will be presented.

Regency Foyer Sheraton Centre

Session Chairman: A. H. Clauer, Battelle Labs, 505 King Ave., Columbus, OH 43201

(2:00p.m.) MICROSTRUCTURAL DESIGN AND CONTROL THROUGH CONSOLIDATION

PROCESSES: A. H. Clauer, K. E. Meiners, and A. N. Patel, Battelle I s Columbus Laboratories, 505 King Avenue, Columbus, Ohio. The use of powders, fibers, and strip for consolidation into bulk materials often provides a wider latitude for design and control of microstructures than does ingot metallurgy. A variety of metal alloy and ceramic materials combinations can be synthesized into microstructural combinations that cannot be achieved by other processing methods. In addition, the various consolidation processes provide further latitude in the variety of microstructures which can be achieved. This paper will discuss the various consolidation processes and the microstructures and microstructure concepts associated with them.

(2:35 p.m.)

(3:40 p.m.) "PUISTIC INSTABILITY OORING TENSILE DEFO~IATIrn OF FINE GRAINED Al 2 wr % Fe - 0.8 wr % Mn ALI.JJY", Hakon Westengen, Ardal og Sunndal Verk a.s., R&D Departrrent, PostbokS 51, N-660l SunndalS¢ra, Norway. Untrafine grained sheet materials are processed flXlll a continuously strip cast Al-2 wr % Fe - 0.8 wr % Mn alloy. By varying the process paraneters, particle stabilized grain structures with nean grain dianeters in the range 0.8 - 5 ).JIll are obtained. Fefinenent of the grain structure provides an efficient hardening nechanisrn. The practical application of this hardening nechanisrn is however, limited by a tendency for inharogeneous deformation. During tensile testing, yield point effects, ludering and strain localization are observed. 1.he influence of grain size, test t:erperature and strain rate on the tensile properties is described. It is shown that dynamic recovery effects play an inportant role during deformation of these materials.

Microstructural Model for Liquid Phase Sintered Materials R. M. Germa.n, Materials Engineering Department, Rensselaer Polytechnic Institute, Troy, NY 12181 Contiguity, connectivity and shape accomodation are treated using geometric and thermodynamic models. These calculations show the basic relations between the material properties (interfacial energies), processing parameter." (volume fraction liquid) and powder characteristics (size distribution). A maxi~um v?lume fraction of solid phase is calculated for full dens1ty Slntered materials depending on the materials properties. Variations in mechanical properties are discussed versus the model to show the microstructure-process ing-property links. The results are discussed with reference to heavy metals and cemented carbides.

(3 :10 p.m.)

(4:05 p.m.) "'IHE INFIlJEl'lCE OF SOLIDIFICATIrn RATE AND 'lllElM'IL PRA== rn 'IHE ~ ClIARACI'ERISTICS AR(l) ~tals a:npany, AR(l)

MICROSTRUCTURAL CONTROL VIA POWDER METALLURGY II Sponsored by the Solidification and Powder Metallurgy Committees of TMS-AIME

OF AA ALI.JJY 3003", William C. Setzer, Aluminum, Mill Products, Wuisvl.lle, KY

40202. 1.he annealing behavior of the cc:tmerical aluminum alloy 3003 containing naninally 1% manganese plus inpurities has been studied. The microstructure has been characterized and the influence of solute disposition upon the isothermal annealing characteristics neasured against tine by neans of hardness, fraction recrystallized and electrical conductivity

(solute level). Because of the manner in which 3003 solidifies, significant local variation in the mi=structure occurs which causes the alloy to take on the characteristics of a catpOsite material. The thernn treatrrent preceding deformation also plays an important role in that it determines the local solute level and the size, density, and distribution of second phase particles. The fOIIOOr influences and incubation tine while the latter influences the rate at which recrystallization preceeds to the degree that the annealing characteristics of this alloy can vary by large orders. of magnitude. Operative factors are reviewed and rreans for producing "nonnal" recrystallization characteristics are discussed.

MI CROSTRUCTURAL CONTROL I N AN A1-2. 3L i -1. 1Zr ALLOY THROUGH RSP AND TMT, Frank W. Gayle and John B. Vander Sande, Department of Materials Science and Engineering, M.LT., Cambridge, MA 02139 A13X phases of the L12 structure are metastable in both the Al-Zr and Al-Li systems. In the former the precipitation reaction occurs only at high temperature (e.g. 500'C) due to a low DZ r , and in the latter system only at normal aging temperatures (e.g. 190'C), due to the large solubility of Li in A1. An Al-2.3Li-1.1Zr alloy has been inert-gas atomized so as to create a large supersaturation of Zr. Subsequent processing has resulted in the precipitation of a complex A13(Li ,Zr) phase. Such a ternary precipitate may prove beneficial to tensile strength and ductility of Al-Li alloys. However, an understanding of the actual composition of the phase and available methods for contro 11 i ng its compos iti on need to be more fully understood if the maximum benefit is to be realized. An analysis of this problem is presented as studi ed through electron mi croscopy, electron diffracti on and electron energy loss spectroscopy.

(3:30 p.m.)

Break

(4:30 p.m.) "DYNAMIC RECRYSTALLIZATION IN ALUMINUM-MAGNESIUM ALLOYS", T.J. Sheppard, Imperial College, London, England Dynamic recrystallization has been observed in AI-Mg alloys. Using results obtained in rolling and extrusion experiments it is shown that percent recrystallization rises with increasing Mg content. The nucleation is

discussed and is shown to differ from that observed in low stacking fault energy materials. Alloys prepared from rapidly solidified powders exhibit complete dynamic recrystallization.

(3:40 p.m.) CHARACTERIZATION OF A PIM Al-L i -Mg-Zr ALLOY PRODUCED FROM PULVERIZED MELT-SPUN RIBBON: G. Hari Narayanan, B. L. Wilson, S. W. Ping* and W. E. Quist, Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, WA 98124, *Kaiser Aluminum & Chemical Corp., Center for Technology, P.O. Box 877, Pleasanton, CA 94566 A low density Al-3.0Li-5.5Mg-0.2Zr P/M alloy was produced from rapidly solidified powder obtained by pulverization of melt-spun ribbon. Prior to consolidation, the powder was fully characterized to identify appropri ate degass i ng and compacti on parameters. The degradation of microstructure caused by coarsening of the second phase cons ti tuents duri ng each process i ng step was i nvesti gated. The final extruded product was characterized in terms of its tensile properties, toughness and corrosion resistance for several heat treatment conditions. The PIM alloy, while beingAJ13% lighter than the conventional 11M aluminum alloys, exhibited strength and corrosion resistance superior to those of 2024-T3 but was deficient in ductility and toughness. The observed properties have been correlated with the alloy mi crostructure and fracture characteristics. Thi s work was performed under AFWAl,fo1 LLS Contract No. F33615-81C-5053

88 - TMS-AIME Annual Meeting Program (4: 00 p.m.) DYNAMIC COMPACTION AND SUBSEQUENT HEAT TREATMENT OF RAPIDLY SOLIDIFIED Ni, Al AND Ti ALLOYS: R.D. Field, D.J. Miller, S.J. Hales, D.G. Konitzer, D. Watson, and H.C. Fraser, De~t. of Meta 11 urgy and the Materi a 1s Research Laboratory, Unl v. of Illinois, Urbana, IL. Most powder consolidation techniques, such as sintering, hot extrusion, and hot isostatic pressing, involve an extended thermal excursion often resulting in coarsening and transformatlon of the as-rapidly soldified microstructure. Dynamic powder compaction (DPC) offers the capability of consolidating particulate without such excursions, thus allowing more direct exploitation of these microstructures. The application of DPC to Al, Ti, and Nl base alloy systems has been investigated. This investigation includes extensive microstructural studies, using analytical electron microscopy, of both the as-compacted material and specimens which have undergone subsequent heat treatment. Results from these studi es, and thei r i mpl i cat ions concerni ng the mechani sms of interparticle bonding and microstructural control using DPC, will be presented.

(2:20 p.m.) OXIDATION BEHAVIOR OF STAINLESS STEELS, AND IRON-BASE, NICKEL-BASE, AND COBALT-BASE HIGH-TEMPERATURE ALLOYS:

M. F. Rothman, Cabot Corporation, 1020 W. Park Avenue, 'Kokomo, Indiana 46901. The resistance of over 30 high-temperature materials to oxidation in flowing air has been determined for relatively long-term exposures over a range of temperatures. Test samples of stainless steels, and iron:-base, nickel-base and cobaltbase commerciAl alloys were exposed for 1008 hours at temperatures of 980'C (1800'F), l09S'C (2000'F), l1S0'C (2100'F),

and l20SoC (2200°F), with weekly cycling to room temperature. Weight change of the samples was monitored, and full evaluation of the metal loss and internal attack experienced was performed upon completion of the exposures. The oxidation behavior of the various materials are compared in terms of simple \yeight change rankings versus a total metal affected approach. The roles of various elements present in these alloys are discussed in relation to the nature of the oxide scales formed and the mode of internal attack.

(4:20 p.m.) MICROSTRUCTURAL MODIFICATION IN RAPID SOLIDIFICATION PROCESSED (RSP) MAGNESIUM ALLOYS: * P. J. Meschter, R. J. Lederich, and J. E. O'Neal, McDonnell Douglas Research Laboratories, P. O. Box

516, St. Louis, MO 63166.

GRADIENTS:*M.J.Shingler! J.W.Halloran and K.M.Vedula, Case Western Reserve University, Cleveland, Ohio 44106.

Rapidly solidified particulates of pure Mg and Mg-Li, Mg-Li-(Si, Ce), Mg-AI-Zn, Mg-Zn-Zr, and Mg-rare earth alloys have been produced by twin roller quenching at a cooling rate of - 105 K/s. Rapid solidification produces fine-grained microstructures and allows introduction of fine, thermally stable incoherent dispersoids in all Mg alloy classes studied. Microstructural refinement is associated with substantial improvements in mechanical properties of Mg alloy extrusions, compared with those of equivalent ingot-metallurgical (11M) alloys. The corrosion resistance of 11M and RSP Mg alloys will also be compared.

*Research conducted under the McDonnell Douglas Independent Research and Development program.

(4:40 p.m.) PROBLEM OF PRESERVATION OF UNIQUE PROPERITES OF P/M RAW MATERIALS AFTER ENGINEERING PROCESSING: J. Duszczyk and P. Jongenburger, Delft Univ. of Tech., Dept. of Matls. Science and Tech., 137 Rotterdamseweg, 2628 AL Delft, The Netherlands. The paper deals with 7075 aluminium alloy produced by P/M rouZe em§loying a conventional atomisation process (cooling rate 10 10 K/s) and ragid s06idification technology (meltspinning with cool ing rate 10 - 10 K/s). The structures of atomised powders and rapidly solidified flakes as well as their alloying concentration profiles are discussed pointing out a finer and a more homo" geneous microstructure of P/M rapidly sol idified material. The problem of the preservation of metallurgical advantages gained through P/M route is presented on the basis of alloying concentration profiles and properties of P/M products after extrusion and heat treatment. The conclusions are drawn considering optimum features of P/M raw materials from a point of view of their performance during engineering processing (extrusion, heat treatment) .

OXIDATION TMS-AIME General Abstract Session Wednesday, February 27, 1985 2:00 p.m.

(2:40 p.m.) MICROSTRUCTURAL CHANGES IN CoO WHEN EXPOSED TO AN OXYGEN POTENTIAL

Colonial Room Sheraton City Sq\lire

Session Chairman: K. M. Vedula, Dept. Metallurgy & Materials Science, Case Western Reserve Univ., Cleveland, OR 44106

(2:00 p.m.) THE EFFECT OF DISPERSED PHASES ON THE OXIDATION RESISTANCE OF CE-

MENTED CARBIDES. G. P. VJagner * and G. S imkovich **. The Pennsy 1vania State University, University Park, PA 16802 Tungsten carbide based materials, such as rolling and extruding dies, tool inserts, rock cu t t ing equipment and machine components oxidize readily by the formation of CO and CO 2 gases. The evolution of these gases promote the formation of a porous oxide. This porous oxide provides raceways upon which oxygen can readily attack the metal surface. Dispersed phases are extremely useful in the sense- that they can f~rm and maintain a stable., protective oxide scale which grows at a slow rate. Dispersed phases can be incorporated into an alloy without the deleterious effects on mechanical properties associated with some pure oxidation resistant elements. Oxidation kinetics were recorded at temperatures of 700, 800 and 900°c in an atmosphere of dry oxygen at 1.013 x 105 N/m 2 pressure. Typical weight gain vs time curves are plotted and pertinent micrographs are also shown. il"Kennametal Fellow at The Pennsylvania State University **Professor of. Metallurgy at The Pennsylvania State University

High temperature gaseous oxidation conditions experienced by an oxide layer can be modeled and simulated for transition metals by placing an oxygen chemical potential gradient across the bulk samples of a transition metal oxide. In the present experiments CoO was used because its defect and transport properties are well established. The application oxygen gradient drives metal vacancies to the lower oxygen potential surface and cations to the higher oxygen potential surface. This results in a movement of the crystal towards the high oxygen potential. Dramatic microstructural changes are observed at both the advancing and receding interfaces. The lower potential interface becomes eroded and leads to pore formation within the sample. The crystal can move towards the higher oxygen potential with velocites of the order of 10 l.1m/hr.

*

Research sponsored by the Materials Research Lab at CWRU.

(3:00 p.m.) LATTICE PARAMETER, MICROHARDNESS, AND SOLUBILITY-LIMIT FOR TITANIUM OXYGEN SOLID SOLUTlON:* K. E. Wiedemann, R. N. Shenoy, and J. Unnam, Analytical Services and Materlals, Inc., Tabb, VA. Oxygen in excess of about 2 atom percent causes embritt1ement of titanium and some of its alloys. Therefore, it is important that accura te gauges of oxygen content be estab 1 i shed. The oxygen content of Ti-A55 has been cal ibrated using the microhardness technique (KHN) and the X-ray diffraction technique (XRD). Ti6Al-2Sn-4Zr-2Mo alloy was also cal ibrated using the microhardness technique. Solid solution standards were prepared by partially oxidizing the alloys and homogenizing them in vacuum. Calibration data and regression coefficients are presented for the determination of oxygen content by XRD and Knoop-hardness number with 15 g or 5 g indentor loads. The statistical certainty of the measurements is qualified and estimates of precision are made. The solubility limit of oxygen in titanium and its dependence on time/temperature are discussed. *ThlS research is supported by NASA Langley Research Center.

(3:20 p,m.) HIGH TEMPERATURE TENSILE, CREEP, AND OXIDATION BEHAVIOR OF A PLASMA SPRAY DEPOSITED NiCoCrAlY COATING ALLOY: Mohan G. Hebsur and Robert V. Miner, NASA Lewis Research Center, Cleveland, OhlO 44135. A significant increase in inlet temperature has been achieved in modern JT9D engines by introducing the advanced single crystal superalloy 454. As a result of high operating temperatures, the susceptibil ity of turbine blade· to oxidation and hot corrosion problems has increased and so NiCoCrA1Y protective coating is necessary in practice. Numerous studies have been made on the effects of coating on the mechanical properties of superalloys, but few on the high temperature of properties of only the coating material. In view of this, the high temperature tensile, creep rupture, isothermal and cyclic oxidation behavior of a typical plasma spray deposited NiCoCrA1Y alloy have been studied. This work forms part of the ongoing programme to investigate not only fatigue/creep/oxidation behavior of the coating alloy, but also the interaction of the coating with the substrate alloy 454.

TMS-AIME Annual Meeting Program - 89 (3:40 p.m.) THE SUSCEPTIBILITY TO STRESS CORROSION CRACKING OF 40CrMnSiMoVA ULTRA-HIGH STRENGTH STEEL: S. Jin and X. Liu, Dept. of Aircraft Manuf. Eng., Northwestern Poly tech. U., Xian, Shannxi, PRC. New type of 10w2alloy ultra-high szrength steel 4QCrMnSiMoVA (CS"R=191. 7 Kg/mm ; (J =145.6 Kg/mm ; Ks,=213 Kg/mm~; 11.8%) was inVestigated for el~ctrochemical reactivity and its susceptibil ity to stress corrosion cracking (SCC) in 3%NaCl solution and in distilled water. In NaCl solution deaerated at room temperature the steel demonstrated sl ightly passive behavior, and the open circuit potential Eo .• ~as -800mV(SCE). Slow strain rate testing (SSRT) indicated that the susceptibil ity to SCC of the steel was observed only at the strain rate of 10-" sec·' or lower, and markedly dependent on the applied potentials. The ductility decreased more significantly in both anodic(-640mV)and cathodic(-1250mV) range than at Eo." In solution not deaerated the total elongation at -640mV was much higher. It showed thatH absorption in this case might decrease. SEM fractographic examination showed that there were always corrosion tunnel, intergrainular failure and quasi-cleavage on the fracture surfaces. The area of them were dependent on applied potentials. The same pattern was observed on specimens tested in distilled water but less severe. The results of both SSRT "nd SEM analyses indicated that 40CrMnSiMoVA was sensitive to SCC in both cases, and the mechani sm of failure was hydrogen embrittlement cracking.

whether CuAu II is a true long period superlattice or also a two phase mixture. We plan to address this question to the extent that time and circumstances permit.

*Research sponsored by the Division of Energy Conversion and Utilization Technology, U. S. Department of Energy Under Contrac t No. DE-AC05-840R21400 with the Martin Marietta Energy Systems, Inc.

(2:45 p.m.) STABILITY AND PHASE CHANGE MECHANISMS OF COPPER-GOLD ORDERING TRANSITIONS: J. W. Cahn, Center for Mater·ials Science, National Bureau of Standards, Gaithersburg, MD 20899 Although the phase diagrams of fcc ordering transitions to LlO and Ll2 structures show only first-order transitions, there is expected to be a spinodal and a metastable multi-phase critical pOint. For Ll2 ordering the consequences of this are strongly composition-dependent latent heats and interfacial free energies that would tend to zero near the equiatomic composition. The critical point is calculated to become stable for systems with higher-neighbor and/or multi-atom interactions. The consequences for phase change mechanisms will be discussed. (3:30 p.m.)

(4:00 p.m.) A SCANNING TRANSMISSION ELECTRON MICROSCOPY STUDY OF GRAINBOUNDARY CHROMIUM DEPLETION IN SULFUR MOO PHOSPHORUS DOPED TYPE 304 STAINLESS STEEL. Y. Kim, Department of Civil Engineering, Mechanics, and Metallurgy. University of Chicago, IL 60680; J. Don, Materials Science and Technology Division. Argonne National Laboratory, 9700 South Cass Avenue, Argonne, It 60439; J. Y. Park, Materials Science and Technology Division, Argonne National Laboratory, 9700 South Cass Avenue, ,Argonne. IL 60439; and S. Danyluk, Department of Civil Engineering, Mechanics, and Metallurgy, University of C,hlcago, It 60680. Scanning transmission electron microscopy has been performed on grain boundaries of doped Type 304 stainless steel (S5). A commercial heat of 'Type 304 SS was remelted and doped with sulfur and phosphorus to various concentrations. The doped tlaterials were _then isothermally heat treated at 600-850·C for 1-10 hours. These heat treatments produced precipitation of ~arblde., chromlU11l depletion, and segregation of sulfur and phosphot'Us at grain boundaries. The influence of sulfur and phosphorus on the grain-boundary chrcnrlua depletion will be presented. Correlation of the chrom.1U11 depletion to Intergranular corrosion rate and grain boundary fracture strength of the material will also be discussed.

(4:20 p.m.)

HIGH TEMPERATURE TENSILE, CREEP, AND OXIDATION BEHAVIOR OF A PLASMA SPRAY DEPOS !TEO Ni CoCrAl Y COATING ALLOY: Mohan G. Hebsur and Robert V. Miner, NASA Lewis Research Center, Cleveland, OhlO 44135. As a res ult of hi gh turbi ne engi ne operati ng temperatures, the susceptibility of turbine blades to oxidation and hot corrosion problems has increased and so protective coatings such as NiCoCrA1Y are required for long service life. Numerous studies' have been made on the effects of coatings on the mechanical propert i es of supera 11 oys, but few on the hi gh temperature of properties of only the coating material. In view of this, the hi gh temperature tens il e, creep rupture, i sotherma 1 and cycl i c oxidation behavior of a typical plasma spray deposited NiCoCrA1Y alloy have been studied. This research forms part of an ongoing program to investigate not only fatigue/creep/oxidation behavior of the coating alloy, but also the interaction of the coating with the substrate single crystal superalloy PWA 454.

PHASE DIAGRAMS, ALLOY PHASE STABILITY AND THERMODYNAMIC ASPECTS OF NOBLE METAL ALLOYS VI: Structures, Transitions and Interrelationships Co-sponsored by TMS Committee on Alloy Phases, ASM Alloy Phase Diagram Data Committee and ASM-MSD Thermodynamics Committee Wednesday, February 27, 19S.5 2:00 p.m.

Versailles Terrace Sheraton Centre

Session Chairman: R. Schmid, Technical University, Clausthal, Germany (2:00p.m.) THE ROLE OF COHERENCY IN UNDERSTANDING LONG PERIOD SUPERLATTICES* R. O. Williams, Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831

The long period superlattice that occurs in the eu-Au system at 30 at. % Au can be interpreted as being a mixture of the ordered phase and the disordered solid solution. A complete understanding is made particularly difficult because of the effects of interfacial and coherency energy. We will give our current understanding of the problem. It does not appear to be entirely clear

THE RELATIVE SIZES OF AG AND AU IN INTERMETALLIC PHASES: W. B. Pearson, Departments of Physics and Chemistry, University--or--Waterloo, Waterloo, OntariO, Canada. N2L 3G1

Elemental Ag and Au have essentially identical atomic diameters in their f.c. cubic structures, but it does not seem to have been noticed until recently that in mo-st of their intermeta1l1c phases, Au exhibiCs a diameter about 0.050 A smaller than Ag. This will be discussed, with examples, one of which is mentioned here. In their "band-structure" alloys, e.g. b.c. cubic or ordered CsCl type phases with composition controlled at an upper electron concentration of 1.5 electrons per atom, Ag and Au exhibit identical sizes, but in their other phases with the CsCl structure that occur at higher electron concentrations, and which can be considered as "intermetallic compounds", Au appears to be some 0.050 A smaller than Ag.

(3:55 p.m.) CRYSTAL CHEMISTRY OF RARE EARTH-NOBLE METAL TERNARY INTERMETALLIC COMPOUNDS:· K. A. Gschneidner, Jr., Ames Laboratory, Iowa State University, Ames, IA 50011

The crystal structures of the known rare earth metal-nob1e metal ternary intermetallic compounds are reviewed. The crystal chemistry and interrelationships of the compounds are discussed with special emphaSis on the RN 2 X2 phases which have the ThCr 2 Si 2 -type structure (lsostructural wIth the BaA1 4 -type). Here R Is a rare earth metal, N a nobel metal and X gene.rally a group IVB non-metal (SI, Ge) but structures with X = A1 and P are known. *Supported by USDOE, Office of Basic Energy SCiences, Division of Materials SCiences, under Contrct No. W-740S-ENG-82.

(4:20 p.m.) SYSTEMATICS OF ALLOYING BEHAVIOR OF THE NOBLE METALS, L. H. National Bureau of Standards, Gaithersburg, MD'20899

~,

The noble metals (Cu, Ag I and Au) usually behave as a class in

alloying with simple metals, metalloids, or transition metals, whether as hosts, In intermetallic compounds or as dilute impuri ties. Examples will be g1 ven of this behavior I as well as of Importartt differences between the three elements, drawing on the literature and on results presented in this Symposium by other speakers. Volume effects, electronegativity scales, structural maps, heats of formation, and d-band effects will be stressed.

90 • TMS·AIME Annual Meeting Program PROCESSING II: HYDROMETALLURGY Sponsored by the TMS Physical Chemistry Committee and PTDlISS Wednesday, February 27, 1985 2:00 p.m.

Dominion A Sheraton Centre

Session Chairmen: G. W. Warren, Dept. of Metallurgical Engr. and Mate· rials Science, Carnegie·Mellon V., Pittsburgh, PA 15213; J. E. Pahlman, V.S. Bureau of Mines, Twin Cities Research Center, Minneapolis, MN (2:00 p.m.) MATHEMATICAL MODELING OF ZINC CALCINE LEACHING IN SULPHURIC ACID, E. Peters, University of British Columbia, F.M. Doyle-Garner, N. Ranjan, University of California, Berkeley, CA. A preliminary model for leaching of zinc calcine in sulphuric acid has been tested and modified. The model asswnes that zinc oxide dissolution is controlled by diffusional mass transport of species between the surface of the particles and the bulk solution, that the rate of zinc ferrite leaching is chemically controlled, and that the particles dissolve topochemically. The results of kinetic leaching tests, made with low to' medium initial acidity, which were qualitatively in agreement with the original model, were used to modify the mass transfer coefficients by regression. Although partial leaching tests indicated that significant morphological changes occur during leaching, the correction for this is incorporated in the modified mass transfer coefficients. Equilibrium constants for dissociatio~ of znSo" and HSO" - were recalculated, the solubility of zinc sulphate was measured and the original, empirical expressions for viscosit¥ and density were modified. Finite surface concentrations of Hand HSO" - were introduced. Experimental kinetic results are compared with results predicted by the modified model.

(2:25 p.m.) REACTION KINETICS OF FERRIC CHLORIDE LEACHING OF LEAD SULFIDE-: S-H. Kim, G.W. Warren and H. Henein, Carnegie-Mellon University, Pittsburgh, PA 15213 The reaction kinetics of ferric chloride leaching of PbS concentrate have been investigated for various experimental conditions of agitation, temperature, ferric ion concentration, chloride ion concentration and particle size. These and other experiments have shown that the formation of PbCl 2 is an important step in the reaction mechanism. Previous results of a kinetic study of the dissolution of elemental lead and solubility tests of PbC1 2 in similar ferric chloride solutions have been applied. to the PbS system to help understand the presence of PbCl 2 and the effect of chloride ion. Results show that the dissolution rate of PbS is first order with respect to [Cl-j and is dependent on [Fe 3+j below about 0.6 11 but independent at larger concentrations. The kinetics of the reaction can be explained in terms of a surface reaction model which is supported by the particle size effect and an apparent activation energy of 17.2 kcal/mole.

(2:50p.m.) KINETICS OF PRECIPITATION OF NICKEL FERRITE BY HYDROLYTIC STRIPPING: F.M Doyle-Garner, University of California, Berkeley, CA, A.J. Monhemius, Imperial College of Science and Technology, London, England. Uniform, fine particles of magnetic nickel ferrite were precipitated from a carboxylic acid solvent extractant loaded with Fe (III) and Ni (II), by direct hydrolysis with water at l40-200 oC. The reaction is an example of hydrolytic stripping and can be represented as: (RCOO) 2Ni (org) +2 (RCOO) 3Fe (org) +4H 20=NiFe 20 4 +8RCOOH (org) Homogeneous precipitation occurred in the presence of colloidal graphite, active alumina and silica. Heterogeneous precipitation occurred only in the presence of precipitated ferrite; the rate was linearly proportional to the seed area and independent of stirring rate and [H 20] above the stoichiometric requirement. At [Fe] : [Ni] =2: 1, the rate was inversely proportional to the free carboxylic acid concentration and independent of [Fe] and [Ni]. The rate decreased at [Fe) ;£Ni) =1, 1, but increased at [Fe): [Ni) = 4: I, when NixFe (8-2X) /3°" (x~l) precipitated. The activation energy was 124.4 kJ/moI. A speculative mechanism is proposed to account for the observed kinetics and discussed.

(J: 15 p. m. )

Break

(3:25 p.m.) EFFECT OF SPAN 80 ON COPPER EXTRACTION BY LIX 64N: B. A. Mikucki and K. Osseo-Asare, Dept. of Materials Science and Engr., The Pennsylvania State U., University Park, PA 16802 ABSTRACT NOT AVAILABLE

(3:50 p.m.) REACTIONS IN SOLVENT EXTRACTION SYSTEMS: APPLICATION OF MONOLAYER TECHNIQUES: D. J. Chaiko*and K. Osseo-Asare**, *Mineral ProceSSing, **Dept. of Materials Science and Engr., The Pennsylvania State University, University Park, PA 16802 The Langmuir film balance is a powerful technique for studying molecular interactions at the air/water interface. However, the application of monolayer methods to the investigation of solvent extraction reactions has largely been overlooked. In this paper, the application of film balance techniques to the investigation of interfacial phenomena relevant to metal solvent extraction is discussed. Early results from the study of spread films of solvent extraction rea,gents at the air/water interface will be presented. Experimental measurements include pressure-area isotherms and monolayer dissolution kinetics. This research sponsored by the National Science Foundation, Grant No. CPE-8110756.

(4:10 p.m.) SENSOR DEVELOPMENT FOR HYDROMETALLURGICAL PROCESSES: G.E. Diebold, J. Russ, Physics Dept., H. Henein, G.W. Warren, Metallurgical Engineering Dept., M.W. Siegel,Robotics Institute, Carnegie-Mellon University, Pittsburgh, PA 15213. A multitude of hydrometallurgical processes could benefit from. online, analytical sensors for various dissolved metal components. A multi-disciplinary effort is currently underway to develop two sensors, one based upon I~P and the other on UV-Vis spectrophotometry. The rep is being constructed in-house at substantial cost savings and would provide a multi-component analysis for each sample. The method has shown some success at pressures slightly less than atmospheric and shows promise for applications in process streams containing a small amount of dispersed. solids. UVVis spectrophotometry has been used to successfully develop an analytical process for determining [Pb 2+j in NaCl solutions using an absorption peak in the UV range. Similar work is underway for solutions containing Fe 2+ and Fe3+ in NaCl. The ultimate goal is to develop sensors capable of performing quantitative multi-element analyses on-line.

(4:35 p.m.) T. L. LEACHI NG PROCESS: A PHENOMENOLOGI CAL MODEL FOR OXI DE COPPER ORES TREATMENT: J. R. Rauld, R. Montealegre. P. A. Schmidt and E. M. Oomic; Sociedad Minera Pudahuel Ltda. y Cia. C.P.A., Av. Lyon 527, Santiago - 9 - CHILE Thin Layer (T.L.) leaching process has been in commercial application since 1980 at two operations by Sociedad Minera Pudahuel (SMP) in Chi Ie. Several previ ous papers descri bed concepts, procedured, operating results and main advantages of TL process. Present paper provides a theoretical explanation of the unique characteristics of said process by means of a phenomenological model. As (TL) is a nonconventional leaching process, its hydrodynamiC properties are also very distinctive. Thus, first model's target is to describe, by using the conservation equations, T.L. leaching fluid-flow pattern through ore-bed particles. The validity of the assumptions made, is demonstrated by a series of chemical -tracer tests. Next, a kinetical description of the main leaching reactions is given by using topnchemical approach that matches with experimental resul ts. A practical example on the appl ication of the model to a real ore, is also given. The m.odel allows to predict the effect of the independent variables on the main system responses: metal recovery and acid consumption. Further, by using some other experimentally detennined parameters, the model pennits to obtain the optimum economical operating conditions for applying T.L. leaching to a new ore. All Model equations are differential, so, for resolving them a digital computer was required, both for the parameters adjusting process as well as for obtaining model predictions.

TMS-AlME Annual Meeting Program - 91 STEPHEN R. SHATYNSKI MEMORIAL SYMPO· SlUM ON SURFACES AND INTERFACES-II Sponsored by ASM-MSD Thermodynamics Committee Wednesday, February 27, 1985 2:00 p.m,

Consulate Suite Sheraton Centre

Session Chairmen: Subhash C. Singhal, Westinghouse R&D Center, 1310 Beulah Rd., Pittsburgh, PA 15235; Richard D. Sisson, Jr., Dept. of Me· chanical Engineering, Worcester Polytechnic Institute, Worcester, MA 01609

eu-Ag-Ni system, where the Ag acts as the barrier layer between Cu and Ni, was chosen. Silver barrier layers from 25 \.1m to 2 nun were annealed at 760°C. The breakdown of the barrier layer is caused by the diffusion of Cu atoms to the Ag-Ni interfaces. This non-planar interface grows into the Ag layer during annealing, and serves as a fast diffusion path for copper. A computer model has been developed to simulate the breakdown of the diffusion barrier for a planar interface. The mndel is only qualitatively verified because of the limited diffusion data in the Cu-Ag-Ni ternary system.

('.:15 ".m.) (2:00 p.m.) COMPLEX DEFECTS IN THE OXIDATION OF URANIUM: * C. Co1menares, Lawrence Livermore National Laboratory, Livermore, CA 94550; R. K. MacCrone and S. R. ShatynskiP, Materials Engineering Dept., Rensselaer Polytechnic lnst., Troy 1 NY, 12181.

Thermogravimetric studies of the oxidation of uranium in oxygen, water vapor, and air/water vapor atmospher~s have suggested that the oxidation process is controlled by oxygen interstitial/vacancy defect clusters. An interstitial-rich cluster of the Willis type [2(O~ iO~) 1 has been postulated to control the oxidation of uranium in oxygen, water vapor, and the initial stage in air-water vapor, while a vacancy-rich defect cluster was proposed for the final oxidation stage in air-water vapor. Electron paramagnetic studies of uranium oxides have shown that the vacancy-rich defect displays a strong EPR resonance with a g value of 2.06, and the interstitial defect does not display a paramagnetic resonance. These measurements confirm directly the defect states inferred. from kinetic studies.

ELECTROMIGRATION FAILURES IN VLSI METALLIZATION: K. P. Rodbell and S. R. Shatynskill, Materials Engineering Dept., Rensselaer Polytechnic Institute, Troy, NY 12181 Aluminum alloys have long been used for metallization interconnects op. planar integrated circuits. Under the size restrictions required on these silicon chips, namely very small crosssectional area, these alloys pose reliability threats due to the phenomenon of electromigration. In conventional reliability testing the continuity of the metal is considered the most important parameter. Therefore test stripes are subjected to high current densities for long periods of time (e.g., 10 3 hr. for failure of some alloys). A more reliable resistance monitoring system has been developed which allows accurate predictions of metallization lifetimes to be made in a shorter time than present catastrophic failure techniques. A discussion of this technique, some comparative emf data, and a brief review of the electromigration phenomenon wil~ be included.

II Deceased.

*Work performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under Contract No. W-740S-ENG-48.

(2:)0 p.m.)

*

OXIDATION STUDIES OF NITROGEN-IMPLANTEO SILICON: N. Mohan, J. Thiemer, E. Maby, R. K. MacCrone, and S. R. Shatynski#, Center for Integrated Elec.tronics, Rensselaer Polytechnic Inst., Troy, NY 12181 It has been shown that the implantation of N into Si, followed by heating in a dry or wet oxidizing environment, results in a time delay before oxidation begins. A model has been proposed for this phenomena, namely that an oxidation-resistant nitride layer forms, whose slow oxidation must be completed before growth of the native Si02 can occur. In view of the potential use of this process to fabricate self-aligned contacts, we have studied the oxidation kinetics of N-imp1anted Si during the critically important early stages. The oxidation kinetics of Si implanted with N to fluences of 0.5-2.5 x 1Q16/cm2 have been studied using a thermogravimetric technique in P0 2 = 0.2 atm. at 1000·C. It is found that the "time delay" is in fact a very much reduced linear oxidation rate that slowly gives way to the usual growth behavior. The time delay is not a linear function of dose, ap.d in some cases the final oxidation rate is larger than that of unimplanted S1. These observations are discussed in terms of possible mechanisms of the effect. * This work is supported by the Semiconductor ReseaI'ch Corp.

/I Deceased.

0:00 p.m.) RECOIL IMPLANTATION OF ITO THIN FILMS ON GLASS SUBSTRATES: ~ Harbison Materials Engineering Dept., Rensselaer Poly~echnic Inst., Troy, NY' 12181 Indium oxide and indium tin oxide (ITO) transparent conducting films have been recoil implanted into soda glass. Films were reactively evaporated in oxygen and subsequently irradiated with argon. Implanted .heat mirror films of ITO provide increased coating life~imes, yet produce changes in structural and optical properties. ':l:'hese changes have been characterized using TEM, AES, and visibleinfrared spectrometers. The production of acceptable thin films requires low energy deposition rates during ion bombardment. This places a limit on the extent of film-substrate mixing which is necessary for increasing film lifetimes.

():)O P.Il!.)

Break

("!:45 p.m.) BARRIER LAYERS IN INTERPHASE DIFFUSION: Chun-Sien Lin, Robert A. Rapp, and John P. Hirth, Dept. of Metallurgical Engineering, The Ohio State University, Columbus, OH 43210 Diffusion barriers are essential tQ certain metallization processes and for high-temperature coating systems. This work is a fundamental study of the degradation of diffusion barriers. A model

SOLIDIFICATION II TMS-AIME General Abstract Session Wednesday, February 27,1985 2:00 p.m.

Washington Suite Sheraton City Squire

Session Chairman: R.A. Stoehr, University of Pittsburgh, Dept. of Met. Engrg., 848 Benedum Hall, Pittsburgh, PA 15261

(2:00 p.m.) EFFECT OF SHIELDING GAS COMPOSITION ON FUSION ZONE GEOMETRY OF ALUMINUM WELDS: S. Kou and M. Lu, Dept. of Metallurgical and Mineral Engr., University of Wisconsin, Madison, WI. The effect of the shielding gas composition on the arc energy distribution and the fusion zone geometry of aluminum welds was investigated. Ar with various amounts of He was used as the shielding gas in gas-tungsten arc welding of 6061 aluminum, and the energy distribution of the arC was measured. It was found that under the same arc voltage and current, the higher the He content of the shieldi ng gas, the more concentrated the arc energy and the deeper the resultant fusion zone. Under the same arc gap and current, on the other hand, the higher the He content of the shielding gas, the higher the arc energy and the larger the resultant fusion zone.

(2:20 p.m.) EFFECT OF ARC OSCILLATION ON GRAIN STRUCTURE AND SOLIDI FICATION CRACKING IN GTA WELDS OF 5052 ALUMINUM ALLOY:* ~ and Y. Le, Dept. of Metallurgical & Mineral Engrg., University of Wisconsin, Madison, WI. The effect of arc oscillation on grain structure and solidification cracking in GTA welds of alloy 5052 was investigated using a magnetic arc oscillator and the Houldcroft solidification crack test. It- was found that transverse arc oscillation of high ~m. pl itude produced a 1terna ti ng columna r gra ~ ns at 1ow freq~enc 1 es and fine columnar grains at high freq~encles, both reduclng cracking effectively. Oscillation in the intermediate fr~quency range was ineffective in general. The effect of longltudlnal and Circular oscillations was also investigated. IV contrast to the wideiy accepted concept that fine equiaxed grains are most effective in reducing solidification cracking in welds, the present study showed that welds exhibiting fine equiaxed grain structure could in fact be more susceptible to solidification cracking than welds exhibiting certain other types of grain structure. *This work was supported by the National Science Foundation.

92 - TMS-AIME Annual Meeting Program (2:40 p.m.) ASSESSMENT OF STEEL WELD-METAL SOLIDIFICATION CRACKING: E.F. ABO EL-GWAD, Fac. of Enqg., Suez-Canal Univ., Port-Said, EGYPT: M.R. EL-HEBARY, ~L~. EL-SALAt10NI, AND A.H. EL-SAWY', Fac. of En~g. Cairo Univ., Guiza, EGYPT - ..... ---The effects of chemical composition, welding conditions and plate thickness on the weld metal sol idification cracking are studied. The use of the adopted inoculation technique to study the individua 1 effects of Mn-, S-, Si -, and C-contents is here i n descri bed. The resulting weld-metal cracking lengths due to the individual effects, obtained from the deposition of a GMAW single bead on 60° V-groove of CMEA self restraint cracking test specimen, were measured by X-raying the specimens. Cracking index (a representative of weld metal solidification cracking susceptibility) was calculated as a percentage between the total cracking lengths and the weld bead length. The interrelationships between cracking index and each of the foregoing parameters are presented and discussed as well as correlated by empirical relations to make this study useful for computer aided design of steel welded joints.

'Currently, visiting research consultant, Rensselaer Polytechnic Institute's Center for Manufacturing Productivity, Troy, N.Y.

(3:00 p.m.) TIlE OSB OF MOLTIPASS VELDIIG TO CORTROL TIlE MICROSTROCTORI! OF THE VELDDI!POSIT AND HEAT-APFECTID zon IR UTHMAIITEIISITIC STEILS"

H.J. Kim and J.W. Morris, Jr., Lawrence Berkeley Laboratory and the Dept. of Materials Science an!1 Mineral Eng., University of California, Berkeley, 94720 The heat-affected zone of a weld pass in a lath martensi tic steel shows that it consists of three concentric shells. The inner shell contains material that has been grain-refined by recrystallization of the prior austenite grains. The second shell c,?ntains material in which the alignment of martensite laths within packets is disrupted, yielding an extremely fine effective grain size. The third shell contains material that has received a short temper. An appropriate multi-pass welding procedure can create a weld deposit and heat affected zone in which virtually the whole volume of the weldment contains this fine-grained material. The resulting weldments have excellent properties at low service temperatures an'd in the presence of hydrogen. " This work was supported by the U.S. Dept. of Energy under contract 'DE-AC03-76SF00098.

(3:20 p.m.) INCLUSION COARSENING IN AL-CU-MN ALLOYS. Y. R. Chung and To Z. Kattamis, Department of Metallurgy, University of Connecticut, Storrs, CT 06268, and H. D. Merchant, Continental Packaging Co., Stamford, CT 06904. During solidification of dendritic monocrystals of Al-4.5wt%Cu 2wt%Mn alloys the morphological evolution of intermetallic inclusions, such as Al6Mn and the ternary compound Al20Cu2Mn3 which results from a peritectic reaction between the liquid and Al6Mn, was established as a function of time. Coarsening kinetics of A16Mn were studied at various temperatures both above and below the ternary eutectic temperature by arresting crystal pulling for various lengths of time prior to quenching· the remaining liquid. Coarsening of very fine inclusions was studied using melt-spun materiaL Addition of a low melting point element with no solid solubility in aluminum, such as tin, which forms a liquid layer around the inclusions during isothermal holding below the ternary eutectic temperature was found to substantially accelerate coarsening.

(3:40 p.m.)

(4:00 p.m.) FLOW OF INTERDENDRlTIC LIQUID IN ALLOYS: R. Nasser-Rafi. F. Djennas, D. Koegel and D.R. Poirier, The University of Arizona, Tucson, AZ. The results of experiments on the flow of interdendritic liquid through the solid-liquid regions of lead rich Pb-Sn alloys are presented. The alloys were maintained at a uniform and constant temperature. The effects of volume fraction liquid, dendrite morphology and direction of flow relative to the orientation of the primary dendrite arms on the permeability are discussed. Calculated and experimental results for flow are compared for a two-dimensional flow field which takes into account the anisotropy of permeability. This work has been supported by the National Science Foundation, grant DMR-820SSS4

(4 :20 p.m.) TIlE EFFECTS OF LOW-GRAVITY DURING DIRECTIONAL SOLIDIFICATION ON THE MICROSTRUCTURE OF IRON-CARBON ALLOYS: "'P. A. Curreri, "M. Fiske,and "D. M. Stefanescu, ""NASA/MSFC, AL, "The University of Alabama, Department of Chemical and Metallurgical Engineering. Ca.st iron alloys of commercial compositions and prepared from pure components were directionally solidified during aircraft low-gravity (low-g) maneuvers. Solidification was continuous through up to ten maneuvers each consisting of about 25 seconds of low-g (lO-2g) and I minute of high-g (1. Sg). Typically, several millimeters of sample wa~ solidified in each low-g period. Calculations and work with transparent metal model materials indicate that convective and Stokes flows are damped by a factor of 100 within 4 seconds in low-g. Sample composition and microstructure were correlated with accelerometer data. Hypereutetic irons exhibited bands of larger flakes ..·.d nodules usually correlated with low-g zones. The eutectic cell size tended to increase with time in low-g. and secondary dendrite arm spacing was smaller in low-g zones. Abrupt transitions between cellular and planar solidification were often found. Low-g made the interface less stable favoring cellular solidification.

(4:40 p.m.) '·IACROSEGREGATION IN SMALL UNIDIRECTIONALLY SOLIDIFIED Pb-Sn ALLOY INGOTS: L Wang, Department of Metallurgy and Materials Science, Case Western Reserve University, Cleveland, OH 44106; V. Laxmanan, Visiting Scientist, NASA Lewis Research Center, Cleveland, OH 44135; A. L. Maples, Systems Analyst, General Electric Company, Huntsville, AL 35807; and D. R. Poirier, Professor of Metallurgical Engineering, The University of Arizona, Tucson, AZ 85721. Ground-based experimental work on Pb-15 wt.% Sn and Sn-15 wt.% Pb alloys were conducted as a precursor for proposed microgravi ty experiments in the Space Shutt1 e. Samples were uni di rectiona11y solidified at very slow cooling rates. The sample size was 1imited to about 180 grams, whi ch is the maximum si ze in the current shuttle furnace. The total solidification times varied between 30 mi nutes to several hours; tile maximum sol i difi cati on time being about 14 hours. Experimental results have been ana 1yzed usi ng a macrosegregati on computer code developed at Genera 1 E1 ectri c and the Uni vers ity of Ari zona.

THERMODYNAMICS II: SOLUBILITY AND INTERFACIAL ENERGY Sponsored by the TMS Physical Chemistry Committee and the PTDlISS Wednesday, February 27, 1985 2:00 p.m.

Dominion B Sheraton Centre

Session Chairmen: G. Simkovich, Dept. of Materials Science and Engr., The Pennsylvania State U., University Park, PA; S. E. Khalafalla, U.S. Bureau of Mines, Twin Cities Res. Center, Minneapolis, MN

MATHEMATICAL MODELING OF POROSITY FORMATION IN SOLIDIFICATION:

K. Kubo and R. D. Pehlke, Department of Materials and Meta~lur­ gical Engineering, University of Michigan, Ann Arbor, MI 48109 Shrinkage porosity and gas porosity occur simultaneously and at the same location when conditions are such that both may exist in a solidifying casting. Porosity formation in a solidifying alloy, is described numerically, including the possible evolution of dissolved gases. The calculated amount and size of the porosity formed in Al-4.S% Cu plate castings compares favorably with measured values. The calculated distribution of porosity in sand cast Al-4. 5% Cu plates of 1.5 em. thickness matches experimental measurements. Calculated results for steel plate castings are in agreement with the experimental work of Pellin!.

(2:00 p.m.) THERMOOYNAMIC BEHAVIOR OF OXYGEN AND SULFUR IN COPPER-IRON MATTE D. L. Kaiser and J. F. Elliott, Dept. of Materials Science and Engrg .• Massachusetts Institute of Technology, Cambridge, MA 021: The behavior of oxygen and sulfur in copper-iron mattes at 12000 has been established using a flowing gas equilibration system. Mattes containing 35-70 wt% Cu were equil ibrated in atmospheres with oxygen pressures in the range of 10-9.5 to 10- 8 atm and su1 fur pressures of 10- 3 to 10- 1 . B atm. Measurements were conducted to -determine conditions at which magnetite would precipitate from the matte. The equation describing the oxygen concentrations in mattes is: wt% 0 = 6.002 POg·2665PsiO.0934 (1 + 9 WFe)2.139 WFe is equal to wt Fe/(wt Fe + wt Cu). The oxygen concentration of mattes saturated with magnetite is wt% 0 (matte) = 0.31 + 0.44 WFe + 14.25 WFe2

TMS-AIME Annual Meeting Program - 93 (2:20 p.m.) SOLUBILITY OF S03 IN THE LIQUI D PHASE OF THE Na2S04-COS04 SYSTEM, 1100-1200 K: R. K. F. Lam and J. F. Elliott, Dept. of Materials Sci~nce and Engineering, Massachusetts Institute of Technology, Cambri dge, MA 02139 The solubility of S03 in the liquid phase of the binary cobalt sulfate-sodium sulfate system has been determined gravimetrically. The measurements were conducted in alumina crucibles, and the results also show the solubility of alumina in the liquid phase. The results are interpreted in terms of the formation of aluminum sulfate that is dissolved in the liquid. (2:40 p.m.) INTERFACIAL ENERGIES IN THE Fe-FeS-FeO SYSTEM, l380-l5280 C: R. C. Sussman, Research Laboratory, Armco Steel Corp., Middletown, OH 45043; J. A. Isaacs and J. F. Elliott, Dept. of Materials Science and Engrg., Massachusetts Institute of Technology, Cambridge, MA 02139 The interfacial energies among the phases in the Fe-FeO-FeS system have been measured by thermal grooving, polyphase contact angle and sessile drop techniques. Particular attention is directed to the thermal-grooving method and the experimental technique. The interfacial energy of the liquid metal-liquid oxysulfide phases in the system range from 0 at the plait point to approximately 300 millijoules/m2 on the iron-oxygen side of the system.

for this particular study were based on the CaO-A1203 binary system. Industrially, these oxides are important since they form the basis for a hi gh proportion of ESR and 1adle treatment fl uxes as well as occurring in blast furnace slags and casting mold powders. Use of the thermogravimetric technique facilitates collection of very precise thermodynamic and kinetic data and also eliminates the need for sampling. This avoids problems associated with gas evolution during the sampl ing of basic slags which do not readily quench to a glassy structure. Experiments were performed at temperatures between 1450 and l575°C with Si02 contents varying from o to 15 wt%. The res ults obta i ned have been compa red with da ta available in the literature for C02 solubilities in other slag systems, determined by di fferent experimental techniques.

(4:30 p.m.) THE TEMPERATURE DEPENDENCE OF THE SULFIDE CAPACITY OF SLIIGS: D.J. Sosinsky and 1.0. Sommerville, Department of Metallurgy and Materials Science, University of Toronto In previous pUblications, an excellent correlation was shown to exist between the optical basicities of slags and the logarithms of their sulfide capacities at l500°C. The relation for l500°C, based on data for seven slag systems involving CaO, MgO, A1203, Si02 and B203 is: 10gC s =12.6'\ - 12.3. This work has now been extended to include data at l550°C and l650°C, and similar relationships have been shown to hold. The data at l650°C for six slag systems involving CaO, MgO, A1203, Si02 and P205 yields the relation: 10gC s =15.0'\ - 13.3. The reasons for, and the significance of, this temperature dependence are briefly discussed.

(3:00 p.m.) INTERFACIAL TENSION OF ALUMINUM IN CRYOLITE MELTS: To Utigard and J .M. Taguri, Department of Hetallurgy and Materials Science, University of Toronto, Toronto. The interfaci-al tension between aluminum and cryolite melts with different salt additions has been measured based on the sessile drop method and a X-ray radiographic technique. A computer program was used to calculate the interfacial tension from approximately twenty randomly measured coordinate points

THURSDAY AM

of the drop profile. Aluminum and salt mixtures containing different amounts of Na J AIF 6 , AIF 3 , NaF, Al,03' CaF 2 , KF and LiP were melted in grapnite or alumina crucIbles in a graphite resistor furnace under an argon atmosphere. The interfacial tension was strongly dependent of the NaF/AIF 3 ratio. In the AIF) rich region the interfacial tension was found to be approximately 650 mN/m at 1273 K, while it was approximately 360 mN/m in the NaF rich region. Additions of AI:z03 increased the interfacial tension for a given NaF/AIF 3 ratl0. The change in interfacial tension with composition is explained by sodium enrichment of the Al/melt interface. KF was found to be strongly surface active, while CaF 2 and LiCl slightly increased the interfacial tension.

(J: 20

D.

m. )

ALUMINA AND BAUXITE VI: Formation and Properties of Alumina Sponsored by TMS Light Metals Committee Thursday, February 28, 1985 8:30 a.m.

Royal Ballroom B Sheraton Centre

Session Chairmen: M. Chaubal, C.O. P.O. Box 9911, Corpus Christi, TX 78469; L. Chin, Aluminum Company of America, P.O. Box 300, Bauxite, Saline County, AR 72011

Break

(8:30 a.m.) (3:30 p.m.) SURFACE TENSION MEASUREMENT OF LIQUID METALS, PART I: ~, W.B. Chung, A. McL~an and W.A. Miller, University of Toronto, Toronto, Ontario, M5S lA4 The surface tensions of pure liquid metals and alloys have been measured by both the sessile drop method and the oscillating drop method. The pure metals chosen for this study were Fe, Ni, Co, Cr, Cu, Sn, Ag, and Pd, and the alloys were Ni-Cu, Ni-Sn and FeCr. Almost all of the surface tension values of pure liquid metals and alloys obtained by the oscillating drop method were higher than those by the sessile drop method and/or other values in the literature. Whiie the actual values differed, the relative effects of alloying elements on the surface tension were very simil ar with both methods.

(3:50 p.m.) SURFACE TENSION MEASUREMENT OF LIQUID METALS, PART II: K. Nogi, A. Mclean, W.A. Mill~r, University of Toronto, Toronto, Ontario M5S 1 A4 The effects of copper and tin on the surface tension of iron, nickel, and cobalt have been measured by the oscillating drop technique. Except for the surface tension of the Ni -Cu alloy which behaves almost idealy, all the others show a significant decrease in the surface tension with alloy content. The difference in 'the behaviour of the surface tension of these liquid alloys is discussed with reference to the activity of the alloying element.

(4:10 p.m.) A THERMOGRAVIMETRIC STUDY OF C02 DISSOLUTION IN CaO-A1203 BASED SLAGS: D.J. Sosinsky, 1.0. Sommerville and A. Mclean, Department of Metallurgy and Materials Science, University of Toronto A thermogravimetric technique involving continuous weight measurement has been used to study the thermodynamics of C02 dissolution in metallurgical slags. C02 solubilities are of interest since they may serve as an indicator of slag basicity. The slags chosen

n;;cHNOUX;Y CF
Soda is picked up in alumina trihydrate during the precipitation fran sodium aluminate solution. Soda oontent in the new precipitate was examined by laboratDl:Y scale experiments using plant liquor. '!he precipitation tenperature and the supersaturation of alumina in the liquor have strong effect on the soda pick-up, the seed charge has litUe effect. '!he first instance of soda control technology is lCM-soda hydrate production. Soda oontent decreases to less than 0.1% with proper tenperature am. I1"Olar ratio. 'll1e seoond instance is the delicate oontrol of soda for Slrelting grade alumina. 'Ihe nechanism of soda pick-up is also discussed.

(9:00 a.m.) PRECIPITATION TECHNOLOGY: J.L. Anjier and M.L. Roberson, Kaiser Alwninum & Chemical Corp., Baton Rouge, La. The precipitation of alumina trihydrate crystals from super-

saturated sodium aluminate solution is a key step in the Bayer process. After remaining basically unchanged for many years, a combination of economic and environmental factors have necessitated major changes in the processes and equipment used to produce these crystals. Increased energy costs have caused operators of the "American" Bayer process to increase yields, while producing coarse, sandy alumina. At the same time, the use of dry gas scrubbers at smelters has caused operators of the "European" process to produce coarse, sandy alumina~ while maintaining high yields. The more rigorous conditions of stationary calc.iners have promoted the development of process improvements to increase alumina particle strength to reduce product dustiness. This paper reviews technology developed to meet these changing rE"quircments.

94 - TMS-AIME Annual Meeting Program (9:30 a.m.) THE GENERATION OF FINES DUE TO HEATING OF ALUMINA TRIHYDRATE: J D

Zwicker, Alcan International Limited Kingston Laboratories, P.O. Box 8400, Kingston, Ontario K7L 4Z4, Canada.

The increase in fines during the calcination of trihydrate, especially in fast fluid beds, is of concern to both producer and user. To identify the factors in calcination which influence fragility, laboratory studies have been carried out covering static to flash heating. Questions such as explosive generation of fines, particle shrinkage, and effect of rate of heating were examined. Most work was done using powders hut some single particle studies were carried out. L

(10:00 a.m.)

Break

ALUMINUM REDUCTION TECHNOLOGY V: Fundamental Studies Sponsored by TMS Light Metals Committee Royal Ballroom A Sheraton Centre

Thursday, February 28, 1985 8:30 a.m.

Session Chairmen: R. D. Zabreznik, Kaiser Aluminum & Chemical Corp., P.O. Box 1600, Chalmette, LA 70044; A. R. Johnson, Kaiser Aluminum & Chemical Corp., Center for Technology, P.O. Box 0877, Pleasanton, CA 94566

(8:30 a.m.)

(10:30 a.m.) MORPHOLOGI CAL ANAL YS I S OF ALUM INA AND ITS TRI HYDRATE: H. P. Hsieh, Alumina, Chemicals and Ceramics Division, Alcoa Laboratories, Alcoa Center, Pennsylvania 15069 Available morphological analyses for fine particles are briefly reviewed. Three methods for characterizirig morphology of alumina and hydrate are studied in some detail; shape factor by Optomax Image Analyzer, signature by sieve cascadography and Fourier method. The shape factor represents only a global deviation from a circle or a sphere and does not fully reflect small scale protuberances on the particle profile. The sieve cascadography, when fully developed, can be a useful tool for shape characterization. The corrmercially implemented Fourier ana lys is provi des i nformat i on on both gl oba 1 and 1oca 1 shape features by its morphological descriptors which can be used for distinguishing various types of particles. An example is given in which a newly defined "blockiness index" from a combination of Fourier descriptors is used to identify and quantify the blocky a 14mi na or hydrate crysta 1s.

AN EXPERIMENTAL STUDY OF CURRENTS, MAGNETIC FIELDS AND VELOCITIES IN ALUMINUM WITHIN AN INDUCTION FURNACE: Ch. Vives and R. Ricou, Laboratoire de Magn<,tohydrodynamique, Centre Universitaire, 84000 Avignon, France. The principle of probes for current density, magnetic field

components and the phase angle between them is described. Methods permitting deduction of the electromagnetic force field within the skin depth of an aluminum alloy are also presented. Veloci ties have been measured in molten aluminum using a novel magnetic probe. This sensor yields the local instantaneous values of the velocity vector at temperatures up to 700 0 C. Measurements r_eveal the classical two main cells and show that the regions of vertical flow along the wall are narrow. The effect of the

roughness upon the turbulence inside the boundary layer and on the mean velocity is also revealed.

Examination of current density

and magnetic field patterns show that the electromagnetic end effects, responsible for the stirri ng, are marked.

(9:00 a.m.) (11:00 a.m.) ALUMINA MORPHOLOGY AND PARTICLE STRENGTH J. Bachmann, S. Molnar, W. Stahlin Swiss Aluminium Ltd., Research & Development CH-8212 Neuhausen, Switzerland Alumina particle stability against breakdown is of importance mainly in two areas: alumina calcination and transport of alumina in shipping, dry absorption and feeding to smelter cells. Particle strength is measured with the attrition index. Particle structure is revealed by SEM pictures and micrographs of thin sections. A comparison of alumina hydrates and alumina of different plants is made based on attrition indices and particle structure.

(11:30 a.m.) EURALLUMINA APPROACH FOR A BETTER ACCURACY IN SIEVE TESTING OF ALUMiNUM TRIHYDRATES AND ALUMINAS: S. Perra, Eurallumina S.p.A.

J

Portoscuso, Sardinia, Italy

ACTIVITIES IN Li3A IF - Na AIF MELTS: E.W. Dewing, Alcan Internat iona 1 Liiliite8 King~ton6Laboratories, P. O. Box 8400, Kingston, Ontario K7L 4Z4 Canada. Activities have been derived from measurements of the concentrations of Li and Na in Al in equilibrium with the melts at 1020'C; the necessary mathematical treatment, involving the Gibbs-Duhem equation, is given. The activity coefficients are given by log YAl F3 =-3.034 + 3.342 NLiF - 0.848 N2LiF log

YNaF

=-0.246 - 1.114 NL iF -

log

YLiF

= 0.158 - 0.266 NL iF -

2

0.283 N LiF 2 0.283 N LiF

The measured activities account for the shape of the vapour pressure curve. The increase in total pressure when Li3A1F6 is added to Na1AlF6 is due, not to the appearance of LiAIF in the gas, but t~ th~ increased pressure of NaA1F4 fOllowing 4the rise in A1F3 activity.

(9:30 a.m.) PHASE AND CHEMICAL RELATIONSHIPS OF ELECTROLYTES FOR ALUMINUM

Studies were carried out on standardization difficulties on sieve testing of hydrates and aluminas. The weak point was found to be in the sieves although these were certified to meet ASTM specification E 11-70. The magnitude of the problem is exemplified by the following figures related to the -45 micrometers content: same sieve-absolute standard deviation = 0.15% different sieves, same supplier and laboratory - absolute standard deviation = 0.7% among different laboratories the deviation may be 4-5 %. The use of laser beam punched sieves is considered the best technique available. Because of their high cost, these sieves are to be used only to prepare the sieve distribution certificate of the calibrating powder (alumina or hydrate) to be used to correct woven sieves.

REDUCTION CELLS:

A. T. Tabereaux, Reynolds Metals Company,

Sheffield, AL. Freezing point temperatures and chemical composition relationships were established for the electrolyte additives, CaF2, MgF2. LiF, A1203. NaC!, MgCl, and AIF3, in phase equilibrium studies of cryoli~ic melts. A multiple regression solution was obtained for the liquid-solid phase boundary curves of the Hall cell electrolytes.

(10:00 a.m.)

Break

(10:30 a.m.) r1EASUREMENT OF DISSOLUTION RATE OF ALUMINA IN CRYOLITE MELT: H. Maeda, S. Matsui and A. Era, Mitsui Aluminium Co., Ltd. 80 Yotsuyamamachi, Omuta, Japan 836 A study was made of alumina dissolution in cryolite melt. The dissolution rate was found to be strongly affected by the way of alumina feeding. Slow feeding gives a rather slow dissolution, whereas rapid feeding gives rise to the formation of crust, which then melts away rather quickly. Various world-wide samples of alumina were collected for testing. The correlation of dissolution rate with physicochemical properties of alumina, such as specific surface area, alpha-alumina content, L.O.!', etc., were investigated. The effects of bath composition and temperature upon the dissolution rate of aiumina were also studied.

TMS-AIME Annual Meeting Program - 95 (11 :00 a.m.)

(10:00 a.m.)

BATH/FREEZE HEAT TRANSFER COEFFICIENTS: EXPERIMENTAL DETERllINATION AND INDUSTRIAL APPLICATION: Barry J. Welch., Mark P. Taylor, Dept. Chemical & Materials Engineering, Univ.of Auckland. Auckland~ New Zealand. Electrolyte freezing stabilizes the operation of a smelting cell by protecting its sidewalls against erosion. However freezing can also occur during anode changing as the cold block is immersed and this is detrimental to the current distribution in the cell. In both processes a critical parameter is the convective heat flow to the freeze from the superheated electrolyte. Unfortunately this is difficult to determine from plant measurements because of dynamic variations in temperature and composition, while calculation of heat transfer coefficients from literature correlations has been hampered by inadequate knowledge of the thermal driving force and liquid flow pattern. In this paper experimental bath/freeze heat transfer coefficients are presented for both applications and, where possible, compared with theoretical predictions. Combining these coefficients with operating bath superheats enables the prediction of steady and transient ledging behaviour. The dynamic impact of freezing on anodes is also estimated from the transient measurements.

PROCESS CONTROLLED OPERATION OF BAKING FURNACES: F. Keller, Aluminium 1; Chemie Rotterdam B.V., Batlek-Rotterdam, The Netherlands and S. Oderbolz, Alusuisse R&D Carbon, Chippis, Switzerland

The baking operation is by far the most expensive part of the anode production process. The optimization of the baking process according to the latest technology is no longer possible without computerized process control.

The proper utilization of microprocessors for a fully integrated process control will result in the reduction of energy consumption, manhours, maintenance costs, and expenditures for flue gas cleaning.

(10:30 a.m.) ADVANCES IN CARBON BAKING FURNACE REFRACTORIES: J. Michael

McCollum, Harbison-Walker Refractor ies, pittsburgh, PA.

CARBON TECHNOLOGY V Sponsored by the TMS Light Metals Committee Thursday, February 28, 1985 8:30 a.m.

Georgian Ballroom A Sheraton Centre

Session Chairmen: P. G. Campbell, Alumax of South Carolina, P.O. Box 1000, Goose Creek, SC 29445; C. D. Jurges, Intalco Aluminum Corporation, P.O. Box 937, Ferndale, WA 98248

(8:30 a.m.) INFLUENCE OF AN ANODE EFFECT UPON CARBON SLOQGHING: Euel R. Cutshall, Reynolds Metals Company, Reduction Laboratory-;--p:-o. sox-T2OO, Sheffield, AL; VaughnL. Bullough, Reynolds Metals Company, Carbon Division, 9467 Brookline Avenue, Baton Rouge, LA.

Plant scale experiments involving reduction cell anodes operating at a current density of 1.3-1.4 amp/cm' were conducted to determine the influence of anode effects and anode baking temperature upon carbon sloughing. Our results support the evidence published in the literature that electrolytically generated CO, is forced up through the interior of the anode and reacts most probably with the binder coke. However, this does not seem to be the major cause for carbon sloughing. The working face of all anodes tested was extremely hard and uniform. The side of all of the anodes was much rougher, however. Anode baking temperature was the most influential here. Poorly baked anodes (top layer) had sides which were much rougher and had much looser aggregate than well baked anodes. A single anode effect seems to have little influence upon anode interior texture or surface roughness.

(9:00 a.m.)

Flues constructed of sta'ndard superduty firebrick and high purity superduty firebrick were installed in a modern carbon baking furnace. After having been in service for approximately two years, briCk of each type were removed from service and laboratory tested for mineralogical alterations and wear. Though discoloration due to carbon penetration was similar the structural deterioration of the high purity brick was significantly less than in the standard superduty firebrick. Alkali and fluoride attack and occasional high firing temperature excursions are the major causes of refractory failure in the flues of carbon baking furnaces. The high puri ty superduty refractory shows only minimal subsidence after use in this environment. With an apparent trend toward higher firing temperatures, to obtain better quali ty anodes, using high pur i ty superduty firebrick, with improved resistance to creep and alkali attack, must be considered as a means of extending flue life in a carbon baking furnace. f

(11 :00 a.m.) SIMULATING THE DYNAMICS OF THE ANODE BAKING RING FURNACE: E. Dernedde, M. A. Thibault, R. T. Bui*, A. Charette*, Alcan international Ltd., Jonquiere, Que" Canada G7S 4K8 *Universite du Quebec a Chicoutimi, Chicoutimi, Que., Canada G7H 2BI. A dynamic model for the anode baking horizontal flue furnace is prepeRed, in which the fires are moved stepwise by one pit after each firing cycle, in the same way the real furnace operates. While in a static model the furnace must be treated as a continuous counterflow heat exchanger and consequently we can only obtain a time averaged profi Ie for gas temperature, gas flow and draft along the furnace, this dynamic approach yields these same profiles as functions of- time as wel1. The model successfully reproduces the existing operating conditions of the furnace at Alcan's Grande Baie Works, and also predicts its performance for different firing cycles. It is further shown that the model can simulate the effects of a perturbation and determine the time required by the system to get back to its thermal steady state.

FAST FIRING OF A VERTICAL FLUE RHlr; FURflACE G.S. Sachan, Dubai Aluminium Company Limited, P.O. Box 3627, Dubai, II.A.E.

The Dubal anode bakinq furnaces are of a vertical flue ring main type being initially desiQned to operate on a 42 hour cycle. Our ing the past five year s the fir inQ cyc Ie time has been proqressively reduced to 26 hours. The proqression to a fast firing practice is discussed toqether with the problems which had to be overcome to obtain a 61.5% increase in production with no apparent loss in anode quality.

(9:30 a.m.) EFFECTS OF CARBONACEOUS RODDING MIX FORMULATION ON STEEL-CARBON CONTACT RESISTANCE, P.J. Rhedey, A1can International Limited, Kingston Laboratories, K1ngston, Ontario, Canada K7L 4Z4 and L. Castonguay, A1can International Limited, Arvida Laboratories Jonqu i ere, Quebec, Canada G7S 4K8. Interface res i stance between stee 1 and prebaked carbons as we 11 as carbonaceous mixes was measured in the laboratory as a funct ion of temperature and contact pre.ssure. 0 The latter was determined over the temperature range 50 to 850 C on a product ionsize steel stud/prebaked anode carbon joint assembly. Byaltering the mix composition linear shrinkage of rodding mixes could be varied between 0.4 and 0.05%. Corresponding contact resistances were calculated using the experimental data. It is concluded that for a typical steel/carbon rodded joint carrying 3.2 kA current contact vo ltage drop can be reduced by up to 50 mV when rodding mix formulation and shrinkage are optimized.

CAST SHOP TECHNOLOGY III Sponsored by the TMS Light Metals Committee Thursday, February 28, 1985 8:30 a.m.

Georgian Ballroom B Sheraton Centre

Session Chairmen: G. Lucas, Alcan International Limited, Kingston Laboratories, P.O. Box 8400, Kingston, Ontario, Canada K7L 4Z4 and Charles Vaught, National Aluminum Co., 2800 Grant Building, Pittsburgh, PA 15219

(8:30 a.m.)

™

EXPANDING CAPABILITIES OF THE AIR-SLIP CASTING PROCESS, J. Martin Ekenes and Frank E. Wagstaff, Wagstaff Engineering Inc., N. 3910 Flora Road, Spokane, WA 99216. It has been shown that the Air-Slip Casting Process can successfully produce 6XXX series alloys. More recently other alloys have been cast, including 2024 and 7075. Also increasingly larger sizes are being cast with this technology. This work is concerned with these more recent developments. Sol idification cha racteri st i cs of severa 1 alloys are exami ned. Surface cosmetics is contrasted with internal billet structure.

96 - TMS-AIME Annual Meeting Program (9:00 a.m.) THE AIR-SLIp· CASTING MOLD - AN ESTABLISHED TECHNOLOGY: John P. Faunce, Martin Marietta Laboratories, 1450 S. Rolling Rd.-,--"BaTTIiiiore, MD, 21227, and A. Valdo, Martin Marietta Aluminum, Goldendale, WA, 98620. The Wagstaff AIR-SLIp· casting mold was introduced into Martin Marietta Aluminum plants in 1983 (as reported previously), to produce 6" diameter extrusion billet. Production experience showed this technology resulted in significant improvements in both billet quality and cast shop productivity. Since then, the capabil ities of the process have been eXPanded to cast a variety of alloys (e.g., 1235, 3102, 6463, etc.) and sizes (e.g., 51/8" diameters) with impressive results. A total of over 80 x 10 lbs. of ingot have now been cast by Martin Marietta Aluminum with AIR-SLIp· casting molds making this an established technology. Production data is presented to illustrate the full range of capabilities of the mold. Additionally, quality control and metallographic data are given to substantiate the improvements in ingot quality.

-r

(9:30 a.m.) THE EFFECT OF COOLING WATER QUALITY ON ALWnNUM INGOT CASTING, Ho Yu, Aluminum Company of America, Alcoa Center, PA. In the high temperature quenching process of aluminum ingot casting, boiling is the dominating heat transfer mechanism that affects casting performance and ingot quality. Boiling heat transfer is extremely sensitive to the contaminants and chemical additives in the cooling water. This paper describes some laboratory scale work that demonstrates the effects of the ingot cooling water contaminants and chemical additives on cooling heat transfer and high temperature quenching. Such work provides guidelines for the maintenance of the ingot cooling water system.

CORROSION TMS-AIME General Abstract Session Thursday, February 28,1985 8:30 a.m.

Washington Suite Sheraton City Squire

Session Chairman: W. A. T. Clark, Ohio State University, Columbus, OH 43210

(8:30a.m.) CORROSION BEHAVIOR OF ADVANCED ALUMINUM ALLOYS· J. J. Scutti, K. M. Bresnahan, Northrop Corp., Hawthorne, CA 90250 P.P. Pizzo, San Jose State University, San Jose, CA 95192 Advanced aluminum alloys, such as Al-Li ingot metallurgy (11M) and 7XXX rapid solidification technology (RST) alloys, have shown excellent mechanical and physical properties, making them attractive for application to aircraft structures. However, implementation of these materials is contingent upon their exhibiting adequate corrosion resistance. Therefore, a program to investigate the corrosion behavior of both AI-Li and 7XXX type advanced aluminum alloys is currently underway. The materials selected are being evaluated for stress corrosion and exfoliation resistance, using standard ASTM accelerated tests, and for realtime atmospheric corrosion resistance in both industrial and sea-coast environments. ntese properties will be compared to those of conventional ingot metallurgy alloys. Test results will be presented which have been correlated with microstructural and fracture characteristics by means of analytical methods including transmission and scanning electron microscopy, EDX/WOX analysis, and o~tical metallograph~>

A

etformed under Nor nrop Independent Research and Development.

(8:50 a.m.) (10: 00 a. m. ) El'cC.'nt JeVelopr:lenL~ in Furnace Engineering Techni:jues: ~'L l!lf_ ~an...;-OLl,) ,)\ll'I1,.":'., Gautchi Electro-Fours, Lt~. J

P,O. Box

8274 Taqerwilen / Switzerland 1. The objl'ctive::o of heat treatment havf.' !:'er:lained unchanged. .. i>jodern heat treatment facilities must be designed for very diffe!'cnt requirements. Essential criteria include the following: - Prevention of charge deformation, - minimization of fuel consumption, - automation, - and high availability. 3. Both completely new types of furnace and new furnace components have been developed. New furnaces are of type vacuum, fluidized bed and continuous sheet annealing. New components are c.g. - oxygen probes to control the fuel/air ratio, - new radiant tubes, - and controlled-flow quench baths. 4. A host of new heat treatment processes and teChniques has been developed such as; - techniques for the heat ~reatment of nodular cast iron, - furnace operation at higher Speed, - and new furnace atmosphere control techniques. New developments in furnace design and new proces~;es have reduced the cost of heat treatment and improved material properties. At the sametime, they have helped to lower energy consumption and pollution levels.

STRESS CORROSION CRACKING STUDIES OF MATERIAL USED FOR NUCLEAR WASTE CANISTERS, M. C. Juhas and R. D. McCright, Lawrence Livermore Nat iona 1 Laboratory, Box 808, Livermore, CA 94550 Selection of containment material for the geologic storage of high 1eve 1 nuc 1ear waste is under invest i gat i on by the LLNL, among others. The physical, mechanical, and chemical stability of a metal barrier to survive several hundred years of containment is the paramount technical issue in selecting a suitable canister material. Because of their excellent general corrosion resistance, the austenitic stainless steels have been proposed as the reference canister material. These materials are subject to sensitization, a likely precursor to localized corrosion, as well as other potentially harmful microstructural transformations at the elevated temperatures predicted in the repository. Preliminary results of an in-depth investigation of the behavior of the candidate reference material, Type 304L stainless steel, in repository environmental conditions will be discussed. Emphasis will be placed on phase stability both at high temperature and after local deformation, especially in and around the weld. (9: 10 a.m.)

INVESTIGATION ON STRESS-CORROSION BY EDDY CURRENT MEASUREMENTS: (10:30 a.m.) MODELING OF ALUMINUM REHEATING FURNACE: Y. Sahai, Dept. of Metallurgical Engineering, The Ohio State University, Columbus, OH 43210, and J. A. Clumpner, Consolidated Aluminum Corp .. St. Loui s, MO 63141. This work describes a study of f1uiq flow and associated heat transfer of aluminum ingots in a reheating furnace. The study included the mapping of velocity and turbulence fields in a onefourth scale model of a section of a furnace. A mathematical model has been developed, involving the solution of the turbulent Navier-Stokes equation to represent the flow of gases in such furnaces. Predicted flow fields are in good agreement with those experimentally measured. The heat transfer to the aluminum ingots has also been mathematically modeled. The predicted rate of heating and temperature profiles will be presented. The relevance of these results in industrial furnaces will be discussed.

(11 :00 a.m.)

THE MFS 15 DROSS COOLER INSTALLED AT ALCAN ALUMINUM CORPORATION, OSWEGO, NY: Han Spoel, Spalco Metals Inc .. P.O. Box 785, Cornwall, Ontario, K6H 5T7; J. Philip McMahon, Melting Furnace Services Inc. 7270 Torbran Road, Suites 205/206, Mississauga, Ontario L4T 3Y7; John Crane, A1can Aluminum Corporation, P.O. Box 28, Oswego, NY A large rotary dross cooler, designed and built by Melting Furnace Services Inc., was installed in 1983 at Alcan Aluminum Corporatior.s, Oswego, NY plant. The rated capacity of the cooler is three 5000 lb batches of hot aluminum dross per hour. The paper reviews the history of dross cooling, process and engineering design of the cooler, the first year of operating experience, and the technical and economic results achieved.

I. De Iorio, Istituto di Tecno10gie, Universita di Napoli, 8'0125

Napoli, Italy and F. Rossi and F. Caiazzo, Institute of Mechanical Engineering, Salerno University, Italy. It is known that the aluminum alloys are subjected to stress-cor-

rosion that is aggravated when stressed or compressed material undergoes the damage of alkaline etching. The eventual heat treatments, applied to these alloys, may modify the corrosion speed and intensity. In the literature, the phenomenon is very well known and has been studied. The results obtained with different methods of measurements have been the subject of analysis by classic methods of corrosion measurements. The authors, in this survey, intend to study and analyze the behavior of the material when it is subjected to stress-corrosion, as detected by measurements of variations of the material's electrical conductivity. This method, based on eddy current measurements, offers the possibil ity to put on an accurate investigation on well defined material thicknesses. The penetration depth of eddy currents is a function of the material and, overall, of the supply voltage frequency of th~ testing system. By an accurate selection of the frequency, relldb1e measurements are possible with this technique. This method is able to discriminate the relative influence of the material's previous "history" which is very important to assessing stress-corrosion effects. The aluminum alloys studied are of 6xx.x group, and these have a broad application in the avionic field based on their well: known properties. The stress-corrosion behavior of thes~ alloy~ 1S studied prior to the common heat treatments employed 1n 1ndustrlal practice.

TMS-AIME Annual Meeting Program - 97 (9:30 a.m.)

(10:50 a.m.)

THE EFFECT OF NITROGEN ON THE SUSCEPTIBILITY TO STRESS CORROSION CRACKING OF TYPE 304 STAINLESS STEELS:* T. Aru1 Mozhi, William A.T. Clark and Bryan E. Wilde, Dept. of Metallurglcal Engineering, The Ohio State University, Columbus, OH 43210

EXFOLIATION CORROSION OF RAPID SOLIDIFICATION PROCESSED (RSP) ALUMINUM-LITHIUM ALLOYS: * P. J. Meschter, McDonnell Douglas

The effect of nitrogen and electrochemical potential on the susceptibility to stress corrosion cracking (SeC) of type 304 stainless steels in high temperature aqueous solutions has been investigated. Slow strain rate tests (SSRT) were conducted on steels with varying nitrogen contents and at different applied potentials; the fracture surfaces of the SSRT specimens were then observed using scanning electron microscopy. It was found that the susceptibility to sce decreases with increasing nitrogen up to around 0.16 Wt.%, but at higher nitrogen contents the area fraction of the fracture surface occupied by transgranu1ar stress corros i on crack i ng (TGSCe) is hi gher. The suscepti b i 1 i ty to sce is highest in the potential range -0.1 to OV (volts with respect to standard hydrogen electrode). Possibfe mechanisms for these results will be presented.

Research Laboratories, P. O. Box 516, St. Louis, MO 63166. Exfoliation corrosion tests in aqueous HN0 3 -KN0 3-NaCl solutions have been performed on RSP Al-3Li, Al-3Li-Zr. Al-3Li-Co-(Zr),

Al-3Li-Mg-Zr, and Al-3Li-Cu-(Co,Zr) alloys.

Al-Li alloys not

containing Co or Cu are immune to exfoliation. Large-grained (Zr-free) Al-Li-Co and Al-Li-Cu alloys are mildly attacked. while fine-grained (Zr-containing) alloys of similar compositions are strongly corroded. Heat-treatment variations have little effect on the corrosion resistance of RSP Al-Li-Cu-Zr alloys. RSP Al-Li-Mg-Zr alloys are superior to Al-Li-Cu-Zr alloys as substitutes for 2xxx and 7xxx aluminum alloys based on their superior combination of strength. ductility, and corrosion resistance. *Research conducted under the McDonnell Douglas Independent Research and Development program.

*Work supported by DOE under contract #DE Ae02-81ER10972 (11:10 a.m.) THE ROLE OF MAGNESIUM IN CORROSION FATIGUE OF ALUMINUM ALLOYS: * P. S. Pao, McDonnell Douglas Research Laboratories, St. Louis, MO 63166 and R. P. Wei, Lehigh University, Bethlehem, PA 18015.

(9:50 a.m.) TIlE AQUEOUS CORROSION OF DOPED AND SENSITIZED TYPE 304 STAINLESS STEEL:' J. Chynoweth and S. Danyluk, DepartJ:1ent of Civil Engineering, Hechanics and Metallurgy, University of IL at Chicago Chicago, IL 60680 The weight loss of sulfur and phosphorous doped and sensitized Type 304 stainless steel was measured by the ",odified Strauss test as a function of sensitization tiIile, ter.tperature and, dopant level. The wei~ht loss varied with temperature and linearly with sensitizing time. The slope of weight loss versus time also varied with temperature and reached a maxinum in the temperature range 610-680 oC. The temTlerature at which the ~naximum occurs depends principally on the bulk carbon level. The sulfur and Fhosphorous levels influence the weight loss indirectly in a minor way. A chromium depletion and carbide dissolution model can be used to explain these results.

High-strength AI-Mg-Zn, AI-Mg-Zn-Cu, and Al-Li-Mg-Zr alloys are known to be highly susceptible to corrosion fatigue in the peak aged condition. The susceptibility is believed to be associated with the nature of slip processes, which are in turn affected by the amount and the nature of precipitates in these alloys. Improvement in corrosion-fatigue resistance can be achieved byoveraging, with some sacrifice in strength. Recent study of fatiguecrack-growth kinetics in 7075 and AI-Li-Mg-Zr alloys suggest, however, that this susceptibility may be chemical in origin. In this paper, data that point to magnesium as responsible for corrosion-fatigue susceptibility are reViewed, and preliminary experiments and data that demonstrate the chemical role of magnesium are described. *This work is supported by the" U.S. Air Force Office of Scientific Research under contract No. F49620-Bl-K-0004 and McDonnell Douglas Independent Research and Development program.

*This work was su!,ported in part by the A'!l.erican Iron and Steel

Institute under contract No. 62-440.

(11 :30 a.m.) CORROSION BEHAVIOR OF ADVANCED POWDER METALLURGY ALUMINUM ALLOYS:* M. Khobaib, University of Dayton Research Institute, 300 College Park Drive, Dayton, Ohio 45469, R. Bhattacharya, Universal Energy Systems, Inc., 4401 Dayton-Xenia Road, Dayton,

(10:10 a.m.)

Ohio Ohio

45432, and S. Kirchoff, AFWAL/MLLS, Wright-Patterson AFB, 45433

THE INFLUENCE OF ALLOYING ADDITIONS AND SUBSTITUTIONS ON THE CORROSION AND MECHANICAL PROPERTIES OF LOW CHROMIUM STAINLESS STEELS: J.B. Andrews and C.J. Wiggins, University of Alabama in Birmingham, Department of Materials Engineering, Birmingham, AL. Alloying additions and substitutions were utilized to produce a

Al-Fe-Ce, AI-Li X 2020 and X 7091 have been conducted.

low chromium austenitic alloy that may serve as a suitable re-

Ti-6Al-4V, graphite/epoxy composite AS4, Al 7075-T6 and Al 2024-

placement for type 304 atainless steel. Mechanical properties of the experimental alloys were evaluated using standard tensile testing techniques. Corrosion characteristics were determined using potentiostatic anodic polarization tests in deaerated one

normal sulfuric acid. Results indicated that the influence of any specific alloying addition on both the mechanical properties and corrosion characteristics varied depending on the base com-

position of the alloy. Copper and nitrogen contents above certain limits were found to result in catastrophic intergranu1ar fracture during testing. Molybdenum additions led to improved corrosion properties in all cases investigated.

The corrosion

characteristics of the more promiSing alloys were evaluated in an aerated, two normal nitric acid electrolyte. Results indicated

Detailed investigations on the corrosion behavior of advanced P 1M

The

pitting, crevice corrosion behavior and uniform aqueous corrosion rates of several Al-Fe-Ce alloys, along with X 2020, X 7091, T3 were obtained by polarization techniques. The galvanic corrosion and the exfoliation properties were studied by other standard electro~chemical tests. Corrosion tests were conducted both

in O.IM NaCI and 3.5% NaCI solution.

The results suggest

excellent corrosion resistance behavior for Al-Fe-Ce alloys with

Fe/Ce ratios in the range of 1.17 to 1. 4 (with Fe content up to 9%) •

The exfoliation resistance was found to be far superior to

Al 2024-T3 and X 2020 and X 7091 alloys.

The galvanic corrosion

currents were found to be lowest for couples with AI-Fe-Ce.

"Research Supported by USAF Contract F33615-83-C-5126

that. under this testing condition, corrosion resistance was pri-

marily dependent on the chromium content of the alloy.

(10:30 a.m.) SURFACE ANALYSIS OF 1010 STEEL COUPONS AND OTHER METAL SURFACES FROM A COAL GASIFIER WASTEWATER-FED COOLING TOWER: G. G. Montgomery, M.J. Mitchell, and M.D. Mann, University of North Dakota Energy Research Center, Box 8213, University Station, Grand Forks, ND 58202 SIMS, ESCA, and Auger analysis have been used to investigate corrosion scale on 1010 steel weight loss coupons and heat exchanger tubes. Zinc chromate corrosion inhibitor has been used in some of the test runs of the pilot-scale cooling tower, with a nominal flow rate of 9 gpm and a desired concentration factor of lOx. Auger analysis has been used to measure the zinc concentration at the surface and depth profiles have been used to look at the chemistry with depth at the metal surface. SIMS has been used to identify trace elements. Characteristics of the COOling tower circulating water include 7000 mgll total dissolved solids, 240 mgll alkalinity, 5350 mgll sulfate, 260 mgll chloride, 6 mgll dissolved oxygen, and a conductivity of 13,300 ~mho/cm.

EROSION AND WEAR TMS-AIME General Abstract Session Thursday, February 28, 1985 8:30 a.m.

Colonial Room Sheraton City Squire

Session Chairman: J. M. Rigsbee, Dept. Metallurgy & Mining Engineering, University of Illinois, Urbana, 1L 61801

(8:30 a.m.) THE INFLUENCE OF DEFORMATION-INDUCED RESIDUAL STRESSES IN THE WEAR BEHAVIOUR OF ALUMINUM BRONZES. G. Carro and J.J. Wert, Dept. of Materials Science and Enginemng,-Tanderbilt University, Nashville, TN 37235 An essential process occuring during un1ubricated sliding wear of aluminum bronze is the development and subsequent delamination of a transfer layer. During the delamination process, subsurface cracks develop and propagate parallel to the sliding surface. The presence of a tensile stress perpendicular to the surface should assist the delamination process. A previous study, using the conventional two-exposure X-ray technique, has shown that compressive residual stresses are developed during sliding wear which are linearly related to the wear rate. The goal of this work was to determine the magnitude of the tensile residual stresses developed in the vicinity of the worn surface

98 - TMS-AIME Annual Meeting Program of a series of Cu-Al alloys using a technique developed by J .B. Cohen and H. Do'lle of Northwestern Uni versi ty. The parameters varied were the number of cycles, load, and environment. Research sponsored by the National Science Foundation under Grant DMR-8312241 administered by R.J. Reynik and the SHaRE at Oak Ridge

(8:50 a.m.) MICROSTRUCTLRE AND WEAR MECHANISMS OF LASER PROCESSED CAST IRON*: C. H. Chen, C. P. Ju and J. 't. Rigsbee, Dept. of Metallurgy, University of Illinois, Urbana, IL. Ductile nodular iron specimens have been modified by CO 2 laser processing for enhanced wear resistance. The original and 1aser processed microstructures and hardnesses was correl ated with the laser processing parameters and with the specimen wear rates. TEM, SEM, X-ray, EDAX examinations of the laser processed microstructures and the worn surfaces were used to determine the roles of specifiC microstructures on the wear process. Of special interest was the effect of deformationinduced phase transformation of metastable retained austenite on and during the wear process. The authors gratefully acknowl edge support of the Dep;lrtment of Energy, Materials Science Division through Grant No. DOEDEAC02-76ER01l98.

(10:30 a.m.) THE EROSION OF CORROS ION PROTECTION SURFACES ON STEEL A.V. Levy and G. Hickey, Mats. & Mol. Res. Div., Lawrence

ley Lab., Berkeley, CA

Berke-

94720

Seven protective coating systems including chromizing, aluminizing and plasma sprayed metals that are used commercially to protect the surfaces of chemical process plant structural steel surfaces subjected to aggressive gaseous chemical environments were erosion tested. The erosion metal loss that occurred was measured and the mechanisms that occurred were defined.

FRACTURE III TMS-AIME General Abstract Session Thursday, February 28, 1985 8:30 a.m.

Commonwealth Room Sheraton Centre

Session Chairman: T. M. Bruenig, FMC Corporation, 7805 E. River Road, Fridley, MN

(8:30 a.m.) lNCLINEIJ

PILE

UPS

OF

DISLOCATIONS

AT

THE

CRACK

TIP

WITH

DISLOCATION

FREE ZONES: Y.T. Chou, Lehigh University, ~ethlehem, FA 18015, and C.S. Pande and R.A. Masumura, Naval Research Laborato-ry, Washington, DC 20375

(9: 10 a.m.) *

MICROSTRUCTURAL EFFECTS IN DUAL PHASE STEELS ON liEAR - C. K"ok and

G. Thomas, University of California. Dept. of Materials Science and Mineral Engineering and Materials and Molecular Research DiviSion, Lawrence Berkeley Laboratory, Berkeley, CA 94720 The abrasive wear characteristics of a dual phase steel has been studied. Transmission electron microscopy was used to investigate the extensive microstructural changes that occurred in the heavily deformed subsurface region and the wear debris particles. Results show that improverrent in wear resistance can be attained by appropriate microstructural control through heat treatments.

This work was supported by the Director, Office of Energy Research, Office of Basic Energy Sciences, Materials Science Division of the United States Department of Energy, under contract number DE-AC03-76F00098.

(9:30 a.m.) THE EROSION OF AN ALUMINA-STAINLESS STEEL COMPOSITE:

C. Morrison, H. Conrad and R. O. Scattergood, Dept. of Mat. Engg., Box 7907, N.C. State Univ., Raleigh, NC; J. L. Routbort, Mat. Sci. Div., Arqonne Nat. Lab., Arqonne, lL 60439; R. Warren, Chalmers Univ. of Tech., Dept. of Enqg. Mat., Goteburg, SWEDEN ErOSIon tests were made on a fully aligned, alumina-stainless steel composite material which was spe~ially fabricated by hoti sostat ic pressing. The steady-state erosion rate was measured as a function of the erodent particle size, velocity and angleof-impact. SEM observations were also made for both single impact events on polished surfaces and the steady-state erosion surfaces. The results will be discussed in terms of the erosion behavjor of the individual microconstituents (alumina and stainless steel) and the subsequent effects of microstructure on the behavior of the composite material.

(9:50 a.m.) SAND-WATER SLURRY EROSION OF CARBURIZED AISI 8620 STEEL

A. V. Levy and J. Yan, Mats. & Mol. Res. Div., Lawrence Berkeley Lab., Berkeley, CA 94720; V. D. Arora, F!~C Corp., Box 1580, 205 5. Puente St., Brea, CA 92621 The erosion of case hardened steels used in sand-\.,rater slurry pump service was investigated using a jet impingement tester. The erosion rates and mechanism were determined as a function of carburizing treatment J slurry velocities and particle solids loadings. It was determined that carburizing improved the erosion resistance of the steels and that higher solids loadings of sand resulted in higher erosion rates.

(10:10 a.m.) THE EFFECT OF TEST TEMPERATURE ON THE EROSION-CORROSION OF 9Cr1:10 STEEL A.V. Levy and Y. Man, Materials 6: Molecular Research Division

Lawrence Berkeley Laboratory, Berkeley J CA

A Singular integral equation formulation is developed for a long crack (mode III) with two symmetrical screw dislocation pile ups near the crack tip inclined to the crack by an angle
(8:50a.m.)· GROWTH CHARACTERISTICS OF HYDROGEN-INDUCED INTERGRANULAR CRACKING IN PHOSPHOROUS DOPED AND UNDOPED ALLOY STEELS: J. Kameda, Ames

Laboratory, Iowa State University, Ames, IA

50011.

The characteristics of intergranular crack growth of hydrogenated alloy steels are examined by means of acoustic emission measurements. It has been found that the amount and rate of acoustic emissions induced by intergranular cracking are much larger in Pdoped steels than those in undoped steels. The effect of grain size on the crack growth rate is also examined in two types of the steels. The mechanisms of hydrogen-induced intergranular cracking in these steels are discussed in terms of the analyses of scanning Auger and scanning electron microscopies, and X-rayon intergranular fracture surfaces.

(9:10 a.m.)

ETHYLENE INHIBITION OF GASEOUS HYDROGEN EMBRITTLEMENT IN STEEL: R. p. Gangloff; Exxon Research and Engineering Company, Route ;>2 East, Annandal e, New Jersey 08801 Fatigue experiments with high strength 4130 (1330 MPa) and 4340 (1070 MPa) steels in purified gas environments at 297 K estahlish that ethylene inhibits severe hydrogen embrittlement by a hydrogenation mechanism. For constant stress intensity loading, crack growth in 4130 steel in 40 kPa H2 progresses 150 times faster and along prior austenite grain Doundaries compared to transgranular cracking in 1 ~Pa vacuum. The addition of 40 kPa C2H4 to the H2 envi ronment reduces the crack growth rate by 20fold and produces an inter to transgranular crack path transition. . Reduced ethylene inhibition is observed for lower strength 4340 steel. For each steel hydrogen enhanced crack growth is not i nfl uenced by 40 kPa additi ons of ethane or methane. Such results establ i sh that ethyl ene i nhi bits embrittlement through a hydrogenation reaction involving adsorbed atomic hydrogen on the catalytically active crack surface and unsaturated carbon bonds in the hydrocarbon. Bonding is saturated for C2H6 and CH 4 ; inhibition by hydrogenation is precluded.

(9:30 a.m.) STUDIES ON FRACTURE TOUGHNESS AND FATIGUE CRACK GROWTH IN PRESSURE VESSEL STEELS SUBJECTED TO PRIOR DAMAGE FROM HYDROGEN ATTACK:* R. D. Pendse, E. R. Parker and R. O. Ritchie, Department of Materials Science and Mineral Engineering, University of California, Berkeley, CA 94720.

94720

The erosion-corrosion behavior of 9CrD10 steel was measured as a function of temperature and related to the morphology of the scale produced. It was determined that the material loss rate increases with test temperature but that the rate of loss decreases at the higher test temperatures. Impacting small solid particles were found to enhance the" formation of oxide scales. resulting in scale forming at lower test temperatures than occurred in dynamic corrosion tests without particles in the gas.

Studies have been made on the effects of prior hydrogen attack damage (at 600°C with 17 MPa hydrogen pressures) on fracture toughness and fatigue crack propagation behavior in pressure vesse 1 s tee 1s, A533B and A387. Both mil d degrees of damage, characterized by minor changes in mechanical properties, and severe damage, characteri zed by appreci ab 1e decarburi zati on and swell ing with associated reductions in strength and ductil ity, ha ve been exami ned. Although J Ic toughness was found to be markedly degraded by hydrogen damage, fatigue crack growth

TMS-AIME Annual Meeting Program - 99 behavior was relatively unaffected. Such observations are discussed in terms of mechanisms of crack advance in microstructures which contain gas-filled voids.

(11:10 a.m.) A RATIONALE FOR THE "APPARENT, ANOMALOUS" GRCWTH BEHAVIC'R OF SHORT

FATIGUE CRACKS:

'Sponsored by Fossil Energy Materials Program of U.S. Department of Energy through Oak Ridge National Laboratory. (9:50 a.m.)

SMALL FATIGUE CRACK GROWTH AND CLOSURE IN A NOTCHED AND UNNOTCHED HSLA STEE L : F. Heubaum and M. E. Fi ne, Depa rtment of Materials Science and Englneering, Northwestern University, Evanston, IL 60201 The growth of sma 11 fat i gue cracks and the correspondi ng crack opening displacement and closure loads were measured in both notched and unnotched samples of a vanadium bearing HSLA steel. The higher growth rates of small cracks over conventional long crack behavior and the appearance of growth rate mi nima for cracks emi nat i ng from notches were shown to result from initially lower levels of crack closure. The use of 6~ff minimized these differences between long and short cracks. COO va 1ues of sma 11 cracks also di d not sca 1e wi th crack length. Experiments were performed on both annealed and quenched & tempered microstructures. The annealed sampl es showed somewhat hi gher growth rates due to lower c 1osu re loads. Short crack interact ions wi th gra i n bounda ri es and microstructure were also investigated.

Robert S. Vecchio. Jeffrey Crompton and Richard

W. Hertzberg, Department of Metallurgy & Materials Engineering,

Lehigh University, Bethlehem, PA

18015

Fatigue crack propagation rates were measured for both long and short crack geometries in a p/M Ni-base superalloy. Crack growth rates for short cracks Were significantly higher than those determined from long crack samples when compared at the same 6.K level. Elastic-plastic finite element results, shear lip measurements, and fracture surface morphological information demonstrate that the stress intensity factor is not a suitable parameter for describing the crack growth behavior of short cracks. As such, the anomalous behavior of short cracks relative to long cracks is believed to be due to the inappropriateness in the use of the stress intensity factor to predict the growth of short cracks. Alternatively, an energy approach to the fracture process is considered. Results using the strain energy density concept show that the growth kinetics for both long and short cracks can be described with the same parameter, without the need for "correct ion II fac tors. (Research supported by AFOSR Grant 83-0029)

(11:30 a.m.) DESIGN, DEVELOPMENT, AND OPERATION OF A MULTISPECIMEN CREEP RUPTURE APPARATUS FOR TESTING AT 20.7 MPa HYDROGEN AND 925'C. * Subrata

Bhattacharyya and Crispin Hales, lIT Research Institute, Chicago, Illinois.

(10 :10 a.m.) FATIGUE BEHAVIOR OF THE IRON-BASE SUPERALLOY A-286*

M.A. Daeub1er,

A.W. Thompson and I.M. Bernstein, Carnegie-Mellon University, Department of Metallurgical Engineering and Materials Science, Pittsburgh, PA 15213.

The influence of changes in the nature of the ordered y I precipitate (Ni3 (ri,Al)] on fatigue strength is being examined in the iron-base superalloy A-286 as a function of environmental influences such as dry argon, air, and a stress corrosive medium. Slip distribution, wavyness, and slip step height dewlopment are being measured in an attempt to rationalize the observation that a fine slip distribution leads to a longer fatigue life than does coarse slip. Also, the effect of thermally chal["ged hydrogen on fatigue strength for underaged, peak aged and overaged conditions is being studied. In addition to crack initiation studies, growth rates of short fatigue cracks are being measured on smooth electrolytically polished specimen at R-ratio of 0.1 The anomalies obtained on the micro crack propagation curves (da/dN vs. t>K) will be discussed and analyzed. *This research is being supported by the Basic Energy Science Division of the Department of Energy.

(10:30 a.m.) DISLOCATION-DEPTH DISTRIBUTION WITHIN VOLUME OF SPECIMEN DURING

FATIGUING, I.R. Kramer and C.R. Feng, University of Maryland, 'Metallurgical Materials Laboratory, College Park, Maryland 20742 The dislocation, densi ty was measured by a Fourier analysis of xray line profiles in a series of specimens of 1010. 1040, 1080, 4130 steels and 7050 and 2024 aluminum alloys. The data show that at fracture for specimens fatigued uniaxially (R=-l) the dislocation density was uniform through the entire gage section. For specimens fatigued in 4 poinl bonding, R=-l and R=.15 a large increase in the dislocation density was found in the region of the neutral axis where the stress, as calculated from continuum mechanics was zero. The implications of these findings will be discussed.

(10: 50 a. m. ) THE EFFECT OF COMPRESSIVE UNDERLOADS ON NEAR-THRESHOLD FATIGUE:* C. H. Newton, R. W. Hertzberg and R. Jaccard, Dept. of Metallurgy

and Ma-terials Engineering, Lehigh University, Bethlehem, PA 18015 Compressive under loads have been applied to low crack growth rate fatigue in aluminum alloys and steels. Crack growth rates increased markedly following the application of the underload and a corresponding decrease in crack opening load was observed. When a 6K-decreasing procedure to threshold conditions was followed by a constant 6K regime, similar results were observed. These results are attributed to a minimization of the residual effect of the 6K-decreasing procedure which is frequently used to generate near-threshold results. The accuracy of l\Kth based on current llK-decreasing test procedures is examined and improvements in test procedures are discussed. *This work was supported by Swiss Aluminium Ltd.

Development of automotive Stirling engine using 15 l-fPa hydrogen as the working fluid requires evaluation of economically viable wrought and cast high-temperature alloys in high-pressure hydrogen. Realizing the economic benefit of multispecimen testing in one pressure vessel, a double-walled balanced pressure test unit was designed for 20.7 MFa and 925°C operation. The salient features of the unit are: (1) simultaneous test of six specimens, (2) direct strain measurement from interior using speciallydesigned concentric extensometers, (3) external specimen loading with dead weights, (4) Single support column for all specimens, and (5) vessel trunnion-mounted for easy access. The unit has successfully tested nine iron-base and one cobalt-base alloys in 20 te,sts with the longest test of 1400 h duration. Typical creep elongation-time curves were plotted and rupture life data were analyzed using Orowan-Sherby-Dorn method, and results from two alloys are present ed in t he paper. *This work was supported by NASA-Lewis Research Center, Cleveland.

LEAD, ZINC, TIN III: GENERAL Sponsored by the TMS Lead, Zinc, Tin Committee Thursday, February 28, 1985 8:30 a.m.

Princess Ballroom Sheraton Centre

Session Chairman: John M. Boxall, National Zinc Co., P.O. Box 579, Bartlesville, OK 74005

(8: 30 a.ni.) THE USE OF A "PROCESS CONTROL SYSTEM" IN AN ELECTROLYTIC ZINC PLANT: P. SALOME, A. CAUFRIEZ AND J. L. CORBIAU, MECHIM S.A., BRUSSELS, BELGIUM

The paper explains the methodology applied by Mechim for the realization of control and moriitoring facilities at the PADAENG INDUSTRY Zinc plant in TAK (THAILAND).

The different sections of the complex and simplified flowsheets of the VIEILLE-MONTAGNE process are described. The authors aim at justifying from economical, technical and operating points of view, why a process control system involving a set of industrial computers has been adopted instead of the traditional instrumentation equipment. The favorable influence of the choice on the project completion time s,chedule is shown. Criteria for the selection of the system and the development option are deduced: configuration and software application have been carried out by the process engineering team. As an example of this option, it is shown how the team were led to the development of original software introducing a universal motor control scheme not included in supplier's standard software.

(9:00 a.m.) RESEARCH AIm USES OF ZINC: Dr. J. F. Cole, International Lead Zinc Research Organization, Inc., New York, NY. The zinc industry's cooperative research effort on a worldwide basis has had significant impact on current and projected uses of zinc. Thinwall zinc die castinrs and computer-aided die desien are two of the more familiar results of ILZRO research., with current efforts to improve the die casting process likely to have equally strong impact. Galfan galvanizing alloy is now a commercial reality with Galfan-coated sheet and wire being produced in increasine quanti ties. lVleanwhile, research and field evaluati on of this zinc-5% aluminurn-mischmetal alloy continues. Characterization of casting: zinC' aluminum alloys 8, 11, and 27 also is underway as new uses for these alloys continue to be found.

100 - TMS-AIME Annual Meeting Program (9:30 a.m.) MARKETING ZINC FOR THE FUTURE. Werner T. Meyer, Zinc Institute Inc., 292 Madison Avenue, New York, N. Y. 10017

Selling today is more difficult than ever before, and it will become even more so in the future. In the 70 I S I faced with increasing pressure from competing materials, from economic downturns and I finally I from its own inclination to offer its product rather than market it, the zinc industry suffered declining markets and decreased profits. At that point, the industry began to realize that it must find new products and new ways to promote them. And that is how ZI and its member companies became the cutting edge in expanding existing markets and in penetrating new ones. New or revised promotional programs include Computer Aided Die Design (CADD) and ThinWall zinc die casting for automotive and other applications; the zinc one-cent piece; zinccoated steel for housinq i and zinc oxide/synergistic systems for plastics. At the same time, to protect existing markets and fight for opportunities in new markets, 2I has worked closely Wl. th ~ standards and code-lllaking bodies to obtain maximum penetration for zinc.

(10:00 a.m.) ST. JOE RESOURCES CO. ELECTROTHERMIC ZINC SMELTER AT MONACA, PA: D. E. Warnes and R. L. Williams, St. Joe Resources Company, Monaca, PA, U.S.A. 15061

In late 1980, St. Joe Resources Company reopened the Monaca Electrothermic Zinc Smelter which had been shut down the previous year. The plant was downsized by starting up only the newest and most efficient operating units. Smelter feeds consist of zinc concentrates from Company-owned mines in upstate New York supplemented with purchased secondaries. The present zinc recovery process consists of roasting, sintering, and furnacing. Electrothermic furnace vapors are condensed to liquid zinc which is either cast into product slabs or fed to distillation columns for conversion to either zinc oxide or higher purity metal. Zinc dust is produced with an ISC facility. Additional zinc oxide and zinc dust are produced from Larvik furnaces.

MICROSTRUCTURAL CONTROL VIA POWDER METALLURGY III Sponsored by the Solidification and Powder Metallurgy Committees of TMS -AIME Thursday, February 28, 1985 8:30 a.m.

Regency Foyer Sheraton Centre

Session Chairman: T. H. Courtney, Mich. Tech. Univ., Houghtoh, MI

49931

(8:30 a.m.) DEPENDENCE OF GAS PERMEABILITY ON THE MICROSTRUCTURE OF CONSOLIDATED POROUS MEDIA: D. W. Smith,* C. L. Trybus,* J. E.

Smugeresky,O and B. A. Meyer,O *Dept. of Metallurgical Engineering r Michigan Technological University, Houghton, MI, °Sandia National Laboratories Livermore, CA. Powder metallurgy has been used for many years to produce "controlled porosity" structures, i. e. surface connected pore networks used in flow control and/or filtration devices. Recent work has been directed toward gaining understanding of the characteristics of the pore structure which influence fluid flow through the pores under laminar and turbulent flow conditions. Permeability coefficients have been determined for sintered stainless steel powder compacts with varying pore volume fractions (0.2-0.5). Pore roughness and shape have been altered by variations in particle size, shape, and sintering conditions. Stereo logical and pycnometric methods are employed to define pore geometry. Permeability coefficients are described in terms of this geometry and results compared with phenomenological models. The transition from laminar to turbulent flow is discussed relative to pore roughness and pore network tortuosity.

(9: 10 a.m.) STRUCTURE DEVELOPMENT IN A POWDER-METALLURGY PROCESSED WROUGHT COBALT WEAR-RESISTANT ALLOY, A. J. Hickl, and P. Kumar, Cabot

Corporation, Reading, PA. Cabot-Stellite Division has produced cobalt-base wear-resistant alloys from powders for over twenty years. Recent activities aimed at developing a corrmercial process for the manufacture of Stellite alloy #6B (a Co-Cr-W-C alloy) have resulted in the development of a patented process for producing sintered preforms for eventual wrought processing. The sintered preform is produced by liquid-phase sintering of the alloy to produce a near full density product for further hot working. The liquidphase sintered product develops a microstructure which differs from conventional solid state sintered preforms. The results of this work show the effects of preform structure on eventual

wrought -product structure with regard to grain size and carbide size distribution and the eventual effect of these structures on wear resistance and other properties of the wrought bar. This alloy finds wide-spread use in applications where temperature, corrosion and wear resistance are critical factors in material selection.

(9:30 a.m.) Microstructural Control for Improved Mechanical Properties of Enhanced Sintered Tungsten Alloys, B. H. Rabin and R. M. German, Materials Engineering Department, Rensselaer Polytechnic Institute' Troy, NY 12181 The effects of additive amount and composition as well as sintering variables on tungsten alloys containing various binary mixtures of nickel, iron and cobalt have been studied. Microstructures of specimens that were enhanced sintered by solid state activation and liquiti phase sintering are compared. The roles of phase equilibria and microstructure in determining mechanical properties have been assessed. Beyond densification, severa:' factors appear to be requisite for optimization of strength and ductility. Intermetallic formation, extensive grain growth and impuri ty segregation are detrimental to sintered properties and must be controlled. Additionally, these factors will be contrasted with the previously suspected role of hydrogen embrittlement.

(9:50 a.m.) INNOVATIVE ELECTRICAL APPLICATIONS OF POWDER METALLURGY: K.H. Moyer, Hoeganaes Corp., River Rd. & Taylers, Riverton, NJ 08077

In 1976 a new iron powder was developed with high purity and compressibility, which can be pressed and sintered to greater than 92% of theoretical density. This made it possible for P/M parts to compete favorably with ingot-processed steels in electrical applications. Phosphorous additions to iron increase permeability and lower coercive force, but promote a hot short condition in cast alloys which precludes their commercial use. However, Fe-P alloys can be fabricated by P/M processing. Intermetallic Fe3P particles are blended with the high compressibility iron powder and readily com.pacted. 00" slntering, the phosphorous enters into solution with the iron which increases permeability and lowers coercive force, as well as increasing strength and resistivity. P/M processing makes it possible to substitute Fe-P parts for some Fe-S1 parts required for pulsed DC and power (60 Hz) frequencies. Magnetic properties of the P/M processed Fe-P alloys are discussed along with aging effects. Finally, possible applications of P/M parts in new cost saving electric motors are explored.

(10: 10 a.m.)

THE EFFECT OF GAS ON PORE- FILLING DURING LIQUID PHASE SINTERING: Seong-Jai Cho and Duk N. Yoon,* Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Seoul, Korea Large spherical pores have been produced in a 1 iquid phase sintered Fe-Cu alloy by using spherical Cu particles. When an inert gas (Ar) is entrapped in the pore, the commencement of liquid flow into the pore is delayed by the gas pressure, and gas bubbles remain in the liquid pockets which have been formed 'by the liquid-filling of pores. When NZ gas, which diffuses out slowly, is entrapped in the pore, liquid flow into the pore appears to be controlled by the rate of NZ diffusion. If the pore contains HZ gas, which can diffuse out rapidly, and Ar gas pressure of about 1 atmosphere is appl ied on the speCimen surface, the pore-filling is accelerated. The experimental observations are shown to be consistent with theoretical analyses based on the balance between the gas pressure and the meniscus pressure at the pore and at the specimen surface. • Presently on leave at NBS, Gaithersburg, MD.

(10:30 a.m.) MICROSTRUCTURAL STABILITY AND ELEVATED TEMPERATURE MECHANICAL BEHAVIOR OF plM DISPERSION STRENGTHENED AI-Fe-Ni ALLOYS M.K. Premkumar, M.J~ Koczak and A. Lawley, Dept. of Materials Engineering, Drexel University, Phi1a., PA 19104

Microstructural stability and elevated temperature tensile, compressive and creep properties of rapidly solidified AI-Fe-Ni alloys with A19FeNi dispersoid volume fractions of 0.19, 0.25 and 0.32 have been determined. Air atomized powder was consolidated to full density by vacuum hot pressing and/or hot extrusion. Powder and consolidate were characterized by means of optical and TEM, x-ray diffraction and DSC. Elevated temperature strength, and ambient temperature strength following elevated temperature exposure, confirm the superiority of these alloys over conventional precipitatiori hardening compositions. For example, '"1.160% of ambient temperature yield and tensile strength are retained up to 'V250oC at a dispersoid volume fraction of 0.32. Response to tenSile, compressive and creep loading is analyzed in terms of the initial powder microstructures and changes in microstructure, in particular coarsening, that accompany powder consolidation. Research sponsored by the Air Force Office of Scientific Research.

TMS-AIME Annual Meeting Program - 101 (10:50 a.m.) CORROSION AND OXIDATION BEHAVIOR OF YTTRIA DISPERSED TYPE 304 STAINLESS STEEL POWDER C0I1PACTS: J.H. Gundiler, O.T. Inal arid A. Szecket, Center for Exp los i ves Technology Research, New Mexi co I nst i tute of Mining and Technology, Socorro,NM 87801 Near theoretical density type 304 L stainless steel powder compacts, with and without dispersed Y203 were produced through dynamic sintering that utilizes a two cencentric cylindrical tube assembly and benefits from the adiabatic rise of temperature due to the included air gap along with the explosively induced high pressures. This procedure eliminates the need for further sintering of the green compacts and thus eli mi nates s t ructura 1 changes that are poss i bly detrimental to aqueous corrosion resistance. The compacts were characterized by metallography (optical and SEM) and TEM for structural features, and microhardness and tensile testing for mechanical property evaluations. Corrosion behavior of the compacts were studied by potentiodynamic scans in deaerated lNH2S04 solution, in 10% HN0 3 solution, and by weight loss technique 1n HN03 solution. losthennal oxidation behavior of the compacts in air at 400, 600 and 800 C were studied for 100 hour durations in a thennobalance. Cyclic oxidation tests at 24 hour intervals ~Iere also perfonned at 800 C. Morphology of corroded and oxidized specimens were observed and these results will be compared with tests perfonned on a commercial wrought alloy of similar composition. (11 :10 a.m.)

MICROSTRUCTURAL CONTROL OF ODS ALLoyS:

R. C. Benn, Huntington

Alloys, Technology Dept., P.O. Box 1958, Huntington, WV

25720.

Control of the thermomechanical processing parameters and recrystallization response of oxide dispersion strengthened alloys is required to obtain the very high temperature properties unique to these materials. This presentation covers aspects of microstructural development from an initial period when the feasibility and important variables in determining properties of such materials were completely unknown through a period of methodical investigation of empirical effects -to the present, when alloy developments are based on fairly well established theories relating composition to properties and thermomechanical processing response. Among other variables) the effects of directi~nal re~rystal~ization) grain aspec t ratio, J phase proport1.ons, d1.sperso1.d content and texture on properties will be discussed.

11'

NON ·FERROUS EXTRACTIVE PROCESSING TECHNOLOGY TMS-AIME General Abstract Session Thursday, February 28, 1985 8:30 a.m.

Regency Ballroom Sheraton Centre

thereof, of the artefact. In particular, it was fOlIDd that the rate of reduction was slower at a high temperature than at a low temperature due to the enchanced rate of sintering of the grains comprising the artefact athigh temperature. The rate of reduction of specimens cut from the "as received" material was low due to the low porosi ty. 'Work financed by Bnmswick

~1ining

& Smelting Ltd.

(9:10 a.m.) RECENT ENERGY-sAVING PRACTICES AT HACH:m:JHE SI>1ELTER: E. Nanura, Y. Nishimura and H. Teranura, Hachinohe Smelter, Hachinohe Smelting Co. ,Ltd. 76 A:z.a Hananayachi Oaza Kawaragi Hachinohe Aaoori Fref. Japan 1he zinc-lead blast furnace in Hachinohe coornenced operation in 1969. Toda,y it has an annual production capaci ty of about 100,CXXl tons of zinc plus lead. '!he Smelter consunes coke, butane gas oil and electric power. Wi th energy prices on the increase, energy costs are a major part of total operation costs t and many efforts have been made to reduce energy consumption. 1his report describes energy saving practices carried out at the Hachinohe Smelter throughout the past several years, as follows: (1) Oil saving by inproving the sintering machines's ignition stove (2) Reduction of power consLllption by practical investigation of electric facilities (3) Blast furnace gas utilization (4) Heat recovery fran lead splash condenser (5) Heat recovery of zinc refluxer waste gas. 1hese improvements realized a rema:rl
(9:30 a.m.) DESILVERIZING LOW-SILVER LEAD BULLION:

Jitesh R. Mehta and

Andrew H. Larson, GNS Batteries Inc., St. Paul, MN. A process has been developed for des 11 veri zing lead bullion containing antimony and less than 0.01 wt.% silver. The process includes the steps of heating the bullion to 400°C and adding calcium to the bullion. The added calcitm reacts with the antimony and silver present in the bullion forming silver-antimonycalcium compounds, which rise to the surface to form a silverrich dross. The silver-rich dross is separated from the desilverized bullion and subsequently can be processed to recover the silver. The process is carried out at 400°C in order to effect high desilverizing efficiency, and to provide significant savings in energy, time: and labor over processes preViously used.

Session Chairman: Philip H. Abramowitz, St. Joe Lead Co., Box A, Monaca, PA 15061 (9:50 a.m.) NEW PROCESS FOR OBTAINING A MERCURY CHLORIDE MIXTURE FROM CINNABAR (8:30 a.m.) DISPERSING AND FLOCCULATING EFFECT OF

ORE BY CHLORIDIZING-VOLATILIZATION ROASTING AMINO~ACID

GROUPS

ON DIFFERENT SULPHIOE MINERALS: A. Marabini and M. Barbaro, Istituto Trattamento 'Minerali - C.N.R., Via Bolognola 7, 00138 Roma, Italy; D. It/. Fuerstenau and J. Hanson, Dept. of Mats. Sci. & Enqq., Univ. of Calif., Berkeley, CA 94720, USA; R. Barbucci, Universita, Dipartimento Chimica, Via Pian dei Montellini, 44, 53100 Siena, Italy Dispersing and flocculating effects of amino-acido type reagents have been examined onct:alcoc.ite ,galena, pyrite, sphaleri te in finaly ground state. Reagents errployed were glycine and a polyamido-amine polymer containing glycine functional groups. Sedimentation and Hal I immond flotation tests have been performed on pure minerals at different reagent concentration and pH. Generally both reagents act as di spersant for the mineral s. In f lotation wi th xanthate, the glycine has a promotion action, whi 1st the polymer acts as depressant. Resul ts have been related wi th changes in surface charge of the minerals, determined by Z-meter. By comparing the resul ts obtained on each mineral, conclusions have_ been draWl on the possibi_ Ii ty of using amino-acid groups in the complex sulphide recovery by selective flocculation or flotation.

(8:50 a.m.) KINETICS OF REDUCfICN OF PbO & LEAD MINERALS BY CO/CO2 GAS MIX1URES:· n.R. Morris and M. Hussain, Dept. of Chem. Eng., llniv. of New Bnmswick, Fredericton, N.B., Canada. The kinetics of reduction of PbO, Lead silicate and connnercial lead bearing materials by CO/CO2 gas mixtures were studied in the temperature range SOO to 1000·C. Artefacts were prepared by isostatic pressing of the appropriate powdered materials or, for the connnercial material, by cutting specimens from the "as received" material. The rate of reduction, followed by the gravimetri c method, was domina ted by the poros i ty, or lack

C.NUfiez, A.Roca and M.Cruells. University of Barcelona. Faculty of

Chemistry. Department of Metallurgy. SPAIN.

Diagonal 647. 08028 Barcelona.

A new process for to obtain mercuric chloride or mercuric and mercurous chloride mixture from cinnabar concentrate ore by chloridizingvolatiiization roasting and developed at laboratory scale is presented. This process is based in thereaction between a cinnabar concentrate ore obtained by flotation from Entredicho ,Almadenejos, (Spain),

and a hydrated metallie chloride (6-hydrate A1C13. MgC12 or FeC13) which decomposes in HCl and oxide or oxychloride at a temperatures near to -200 oC. The mixture of reactants is dried at 150°C and then is applied a thermal cycle betwe.en ISO_450°C during one hour. The mercury chloride mixture is separated by water washing. The basic component of the chloridizing agent neutralizes about 40-70 pet. of sulfur gases (as S02 and 803). This neutralization percentage and the mercuric chloride / mercurous chloride ratio obtained depends on the chloridizing agent used and the experimental conditions employed.

(10:30 a.m.) SALT ROASTING VANADIUM ORES WITH ADDED CARBON: J .B. Goddard, Umetco Minerals Corp., Niagara Falls, NY Vanadiferous clays are processed typically by salt roasting at 800-850 0 C followed by water leaching the sodium vanadate. Yields generally fall within the range 75-85% depending on the roast conditions. Reducing agents such as carbon are expected to hinder the roast-leach recoveries by preventing the vanadium from becoming oxidized and water-soluble. However, addition of carbonaceous materials to 'the salt roast feed actually enhances vanadium recovery by about 5%. If the carbonaceous material itself contains vanadium, such as boiler residues from burning high-vanadium heavy crude oil, a synergistic effect on vanadium extraction is exhibited. The carbon must be substantially burned off during roasting. Possible mechanisms for the beneficial,effect of carbon will be discussed.

102 - TMS-AIME Annual Meeting Program (9: 10 a.m.) THE INFLUENCE OF HEAT TREATMENT ON THE MICROSTRUCTURE OF A HIP'd

(10:50 a.m.) REDUCTION CHLORINATION OF BRAZILIAN PYROCHLORE CONCENTRATES: E.A.Brocchi, D.H.Gameiro, DCMM-PUC/RJ. Brazil

NICKEL BASE SUPERALLOY: J. S. Crompton and R. VI. Hertzberg~ Dept. of Metallurgy & Mater1als Engineering, Lehigh Universi ty ~

Bethlehem, PA 18015

Reduction chlorination experiments were carried out with two different brazilian pyrochlore concentrates in order to evaluate the effects of som~ variables on the extent of the niobium pentoxide gasefication as well as to compare the behaviour of the concentrates under the

same

chlorination conditions.

Kinetic curves were obtained with the main variables being temperature, percentage of reducing agent and exposed surface area.

Analysis of the partially-reacted pellets iri terms of niobium pentoxide showed the effect of the studied variables on the structural transformations of the samples, which is a important point in determ~ning the mechanism control of the process. A mass balance was also carried out to estimate the recovery of the gasified niobium pentoxide as a condensed material.

The preparation of material using powder metallurgy techniques provides potentially beneficial control of microstructural inhomogeneities such as segregation. However, additional problems may arise due to inherent porosity and the precipitation of harmful phases during fabrication. In the present work precipitation behavior in L.C. Astroloy has been investigated. The composition and nature of the precipitates has been characterized using standard analytical electron microscopy and diffraction pattern information. The influence of the heat treatments used during fabrication has also been explored. The results indicate that complex distributions of coherent ordered y' precipitates may be developed by incorporating heat treatments, below the y' solvus. Precipitation on the original powder particle boundaries (ppb) give rise to carbide phases commonly encountered in nickel base superalloys. PPB particles were not affected by Simple changes in the heat treatment procedure. (Research sponsored by AFOSR grant 83-0029.)

(11: 10 a.m.)

(9:30 a.m.)

EXTRACTION OF As FROM COPPER REFINING ELECTROLYTE: A. Baradel, San Donato Milanese. Milano. R. Guerriero, Universita de Venezia, Venezia, L. Heregalli and 1. Vittadini, Samin Centro Ricerche Veneto, Porto Marghere, Venezi a. Italy

PRECIPITATION HARDENING, IN RApIDLY SOLIDIFIED Mo ALLOYS. Y. T. Ning and S.H. Whang, Barnett Institute, Northeastern University. Boston MA 02115, and S.C. Hsu, GTE Laboratories Inc., 40 Sylvan Road, Waltham MA 02254.

In copper electrorefining process the bleed of electrolyte 1S 1mportant to maintain the level of impurities (As. Ni, etc.) below predetermined concentrations. This is essential' to permit the production of cathodic copper of the requested purity. Normally, the bleeding electrolyte is treated electrochemically in exhausting cells with many problems both of pollution and recovery of Cu and Ni. New sol vent extraction processes were proposed using TBP and quaternary amlne chlorides (Aliquat 336 or Adogen 464) or mixture of both. These substances are known for their toxicity. SAMIN - Centro Ricerche Veneto has determined the possibil ity of extracting arsenic by an aliphatic long-chain alcohol according to a solvating mechanism without the addition of any other complexing or solvating agent. Laboratory tests were carried out in different extraction equipments; mi xer sett 1ers ~ contactors and co 1umns. It was demonstra ted that the highest efficiency-o~ .. process t5, reached·by-ose-Qi .. apulsed column with organic/aqueous ratio of 5:l. The method was thus proved at pilot scale (100 l/h organic + aqueous phases) in a pulsed column using an industrial electrolyte. In these conditions the yield of recovery is high, the recovery from the stip solution beinq easy and complete.

PHASE TRANSFORMATIONS III TMS-AIME General Abstract Session Thursday, February 28, 1985 8:30 a.m.

Jefferson Suite Sheraton City Squire

Session Chairman: Prof. A. H. King, Dept. of Materials Science and Engineering College of Engineering and Applied Science, State University of New York, Stony Brook, NY 11794

(8:30 a.m.) SOLUBILITY EXTENSION OF BINARY TI ALLOYS THROUGH RAPID QUENCHING.' S.H. Whang, C.S. Chi and LT. Ning, Barnett

Conventional precipitation hardening in Mo rich alloys largely relies on carbide dispersion through direct addition of carbide particles. Recent advent of rapid solidification technology permit novel additives to dissolve and later preCipitate out in the matr i x. In these exper iments, Mo-RE-B alloys (where RE is rare earth metals) were melt~spun into flakes. The microstructures of as-spun and consolidated alloys were

investigated by optical microscopy and TEM. Mechanical properties of the consolidated alloys will be studied by hot hardness testing at a temperature range of 900 0 C to 1, 200 0 C. The results will be presented and potential for applications will be discussed. (9:50 a.m.) THE STRUCTURE OF REAL WELD AND SIMULATED HEAT AFFECTED ZONES FOR A RANGE OF OFFSHORE STRUCTURAL GRADE STEELS: J. T. Bowker, J .A. Gianetto and M.W. Letts, PMRL, CANMET, Ottawa, Ontario, Canada It has been questioned whether heat affected zone (HAZ) simulation techniques 'produce a micrcstructure which closely resembles that of the real weld HAZ. In order to investigate this, measured thermal cycle data for a 3kJ nurr 1 bead on plate weld were used in the simulation of the coarse grained heat affected zone for a range of offshore structural steels. The steels were thermally cycled in a gleeble 1500 simulator to a peak temperature of 1375° C with a cooling time Boo-socf C of 19,6 seconds and dwel1- time above 1000 C of B.6 seconds. The measured thermal cycle was compared. to analytical solutions from a range ,of cooling rate models. Rosenthal's solution gave a cooling time 800-~OO'" C of 17.3 seconds which is in good agreement with the measured value. Quantitative metallography 'Was performed on each real weld and simulated HAZ to provide an identification of gross microstructure and measurements of prior austenite grain size, lath width and packet size of the predominantly ljainitic microstrut;:.ture. Specifically, the prior ~1I!';tpni te 2rain size of the simulated samples was shown to be in better agreement with that of the real weld HAZ than previously reported. Methods to further improve on the simulation technique will be presented.

Institute, Northeastern University, Boston MA 02115. Solubility extension of additive elements is an important premise

for alloy design of RS Ti alloys.

Recently, solubility extension

of various novel solutes has been observed in rapidly quenched Ti alloys. For example, a significant solubility extenSion of metalloid elements is contrasted with very little extension in rare earth elements. In this paper, many binary Ti alloys will be rapidly quenched from the melt into room temperature and

studied by TEM to determine the solubility limit of solutes.

The

results will be analyzed with respect to fundamental parameters and discussed from the viewpoints of thermodynamics and kinetics. Also, a possible mechanism of solubility extension in Ti-B systems will be discussed. *Research sponsored by the Office of Naval Research.

(10: 10 a.m.) ELECTRON MICROSCOPE STUDY OF PRECIPITATION IN A Cu-Ag-Zr ALLOY: p. A. W*cliffe, Rockwell International Science Center, Thousand Oaks, C 91360 NARloy-Z (3.0%Ag-O.5%Zr bal. Cu) is a high conductivity precipitation hardening copper based alloy used as a combustion chamber liner in the space shuttle main engine. Three phases are found in this material in peak-aged condition: Cu, Ag precipitates and the compound (Cu-Ag)9Zr2; with the latter occurring both as primary particles and as fine precipitates. Ag precipitates occur with a cube on cube orientation in a planar array of discrete disc shaped particles. The planar arrays are found on (100) planes and (111) planes of the Cu matrix. The Ag precipitation is explained in terms of nucleation on climbing dislocations.

(8:50 a.m.) ~IICROSTRUCTURAL

OBSERVATIONS OF Ti-CODE 12 (Ti-O.8Ni-0 ..>~lo):

Y. Kohsaka. D. Banerjee and J. C. Williams, Carnegie-Mellon University. Pittsburgh, PA Ti-Code 12 has been developed for use in brine solutions because of its excellent resistance to crevice and general corrosion. Because a alloy used in such applications may be welded, we have studied the microstructural changes which occur during thermal cycles related to welding. The effects of solution treatment temperature. cooling rate and subsequent aging on the microstructure of Ti-Code 12 have also been studied. Using 1 ight and SE~1 metallography and THl we have observed the effects of thermal cycles on the B-phase decomposition and on the formation of Ti2Ni. This paper will describe these results and suggest possible impl ications of these in the context of anticipated applications.

(10:30 a.m.) DESIGN OF MULTIPHASE STRUCTURES IN STAINLESS STEELS:

F. D. S.

Marques, Dept. of Metallurgical Engineering, South Dakota School of Mines and Technology, Rapid Ci ty, SD 57701 Heterogeneous multiphase structures have been designed in stainless steels. The original composi tions of these alloys were adjusted mainly by manipulating the nickel, chromium and carbide forming (titanium) contents. Most of the austenite (Yu) was retained upon water or brine quenching, Partial transformation to athermal martensite (MA) occurred by requenching and soaking into liquid nitrogen. These alloys were then deformed (ausmarforming) up to 80% cumulative plastic strain in the temperature range 77 to 473K which resulted in the formation of martensite (MD). These martensites were then prevented to reverse directly into austenite

TMS-AIME Annual Meeting Program - 103 by annealing (ausmaraging) in the temperature range 673 to 1173K, which produced a variety of microstructures, depending on the dynamic balance between precipitation and recrystallization. Previous athermal and deformation induced transformations supplied an additional mechanism for the control of the grain size and phase shape. Various cycles of these thermomechanical treatments were reapplied to successive microstructures.

SURFACE MODIFICATION TMS-AIME General Abstract Session Thursday, February 28, 1985 8:30 a.m.

Diplomat Sheraton Centre

Session Chairman: R. Kossowsky, Manager Physical Metallurgy, Westinghouse, 1310 Beulah Rd., Pittsburgh, PA 15235

(10:50 a.m.) ELECTRON MICROSCOPY APPLIED TO THE STUDY OF MATERIALS FOR HIGH TEMPERATURE APPLICATIONS: N. G. Needham, Phys. Met. Dept., British Steel Corp., Swinden Labs., Swinden House, Moorgate, Rotherham, S60 3AR, ENGLAND The microstructure of low alloy creeo resisting ferritic steels changes during service at high temperature as a consequence of a thermally activated aging process. The evolution of such structures has been examined in detail in a number of Cr-Mo and Cr-MoV Steels using a scanning transmission electr microscope and hi gh voltage electron mi croscope fitted \vith energy di spers i ve analysis facilities. Exposure to high temperature results in changes in composition of the chromium and iron-rich carbide types M C, M C and M C Wh1Ch can be related to the thermal histor9 of fBe6materi~1~ however, the m?re stabl~ ~hases V4C, and M2C do not show significant vanat10ns 1n compos1tlOn. In aadition, the metastable phases transform to more stable structures, the rate of whigh can be infl uenced by the bu 1k compos i t i on of the s tee 1. It iss hown how these changes in structure are reflected in the solid solution chemistry of the steel. The results are discussed in terms of the evaluation of remanent life of plant operating at high temperature.

(11:10 a.m.) MAGNETO-MECHANICAL EFFECTS IN 304 STAINLESS STEELS • B. Fultz, G. M. Chang, R. Jeopa and 1. W. Morris, Jr., MMRD, Lawrence Lawrence Berkeley Laboratory and the Dept. of Materials Science and Mineral Eng. Univ. of Calif., Berkeley, Calif., 94720.

The martensitic transformation in 304 stainless steels is promoted by low temperatures (T), high stresses (a) and high magnetic fields (D)' The amount of transformation was studied in experiments which manipulated all three variables: T, (J and H. It was found that the flow stress of 304L (and to a lesser extent 304LN) stainless steel is modified in the presence of magnetic fields. These magnetically-induced changes in flow stress correlated to increased amounts of martensitic transformation during magnetic exposure. We suggest that the observed magnetomechanical effects show how the martensitic transformation affects plastic deformation. • This work was supported by the U.S. Dept. of Energy under contract #DE-AC03-76SF00098.

(11 :30 a.m.) INFLUENCE OF TEMPERATURE ON STRAIN INDUCED MARTENSITE TRANSFORMATION AND FCC TWINNING IN Fe-15Ni-0.8C AUSTENITE, Anit K. Sachdev and Michael M. Shea, Metallurgy Department, General Motors Research Laboratories, Warren, MI 48090-9056 The deformation behavior of Fe-lSNi-O.8C alloy in the fully austenitic condition was studied over the temperature range -20°C to 60°C. Strain induced Bce martensite was formed at temperatures above the MO temperature (approximately OOC) and resulted in a rapid rise ~n ductility. The ductility increased ·continuously with temperature and a peak, as is conmonly observed at temperatures above Ma, was not noted. TEM investigations showed that at the higher d~formation temperatures no Bce strain induced martensite was formed. Instead, the substructure was replaced by twins. The twinning presumably provided another mode of deformation as slip became difficult (due to dynamic _strain aging) and led to additional plasticity. This study suggests that deformation of high carbon austenites at temperatures much greater than MO will result in austenite twinning while at temperatures closerSto MO, strain induced martensite will form. Both modes of deformation s lead to enhanced plast ici ty.

1111t

(8:30 a.m.) INYESTIGATION OF ION IMPLANTED SURFACE LAYERS OF AlUMINUM SINGLE CRYSTALS BY X-RAY DOUBLE CRYSTAL DIFFRACTOMETRY: R.N. Pangborn, Pennsylvania State University, University Park, PA 16802, and C .L. VoId and K. S. Grabowski. Naval Research Laboratory, Washington, DC 20375 The magnitude and depth of the damage to the surface of lithiumimplanted aluminwn single crystals have been investigated using x-ray double crystal diffractometry. To limit and control the penetration distance, asymmetrically cut crystals were examined with two different x-ray sources. These procedures permitted the nea,r surface layers of identically implanted specimens to be studied, with probe depths beginning at less than one micrometer. Aluminum single crystal wafers were implanted with lithium at five different energies to produce a surface layer with a nearly flat concentration profile. X-ray rocking curve profiles provided a sensitive measure of the crystal lattice defects and their distribution in depth. Changes in the damage distribution with fluence level and correlation of the results with information provided by other analytical techniques, including Rutherford Backscattering, will be presented.

(8:50 a.m.) ELECTRON IRRADIATION-INDUCED AMORPHISATION IN ~ CuTi D. E. Luzzi, H. Mori, H. Fujita arxl M. Meshii-, Research Center forUITra-Hlgh Voltage Electron Microscopy, Osaka University, Osaka, 565 Japan and *Dept. of Materials Science & Engg., Northwestern University, Evanston, IL 60201 The electron irradiation-induced crystalline to amorphous (C-A) transition in the CuTi phase has been investigated by in-situ observations in an UHVEM at Osaka University. It was found that the C-A transi tion readily·occurred in the Ti-r ich CuTi phase, but was not observed in the Cu-rich CuTi phase. In the Ti-rich region, the transition was marked by a gradual decrease in diffraction contrast accompanied by the appearance of amorphous halos at the expense of the diffraction spots. The dosage required for the observation of the C-A transition was determined as a function of temperature, electron flux and incident electron energy. Within the solubility limit of the CuTi phase, the C-A transi tion was progressively deterred with increasing Cu content. This work was supported by a Fellowship to one of the authors (D.E.L.) from the Ministry of Education of the Japanese Government.

(9: 10 a.m.) COMPARISON OF ELOCTRON IRRADIATION INDUCED AMORPHISATION IN 6, 11 , y,' and 8 Phases of CU-TI Alloys. D. E. Luzzi, H. Mori, H. Fuj ita and M. Meshi i-, Research Center for Ul tra-High Vol tage Electron Microscopy, Osaka University, Osaka, 565 Japan and *Dept. of Materials Science & Engg., Northwestern University, Evanston, IL 60201

Taking advantage of the presence of five intermetallic phases in the Cu-Ti binary system, a comparison of the C-A transitions in these phases was carried out to clarify the urxlerstanding of the mechanisms involved. It was found that a transition similar to that observed in the Ti-rich CuTi' phase occurred in 11 ,Yand e , while no transi tion was observed in 6. In all cases of the C-A transi tion, the amorphous halos that appeared in the diffraction pattern were initially segmented. The position of the segments in the reciprocal space was determined and compared to high resolution lattice images. These results were also compared with those of the amorphous phases produced by 1 iquid phase quenching. This work was supported by a Fellowship to one of the authors (D.E.L.) from the Ministry of Education of the Japanese Government.

(9:30 a.m.) AN INVESTIGATION OF THE CORROSION BEHAVIOR OF B+ IMPLANTED BEARING STEELS:- A. Erdemir, H.J. Kim, W.B. Carter and R.F. Hochman, Metallurgy Program, Georgia Inst. of Technology, Atlanta, Georgia, 30332-0100 The general corrosion characteristics of B+ implanted M-50, AMS5749 and 440C bearing steels were studied. Specimens were implanted with either 40 or 100 KeV ions to a dose of 2xl017 ions/cm'. Potentiodynamic polarization corrosion testing of implanted and unimplanted specimens were performed in deaerated aqueous lN H,SO, solution. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS), both combined with inert gas ion sputtering and transmission electron microscopy (Tm) were uti 1 i zed to characteri ze the surface and near surface regions of unimplanted and implanted specimens prior to corrosion testing. Corrosion tested specimens were examined with secondary electron microscopy (SEI-1), AES and XPS to determine the morpho logy and chemi s try of the corroded surfaces. *This work was supported by NASA contract #NASS-35048.

104 - TMS-AIME Annual Meeting Program (9:50 a.m.)

A CHARACTERIZATION OF ION PLATED TITANILM ONTO GLASS-CERAMIC SLIlSTRATES: R. K. Knipe and J. M. Rigsbee, Dept. of Metallurgy, University of III inois, Urbana, IL. A plasma-physical vapor deposition process, ion plating, has been employed to produce Ti films on alumina and glass-ceramic substrates. This research involves correlations of the ion plating proceSSing parameters with the microstructure and microchemistry of the films and film/substrate interfaces. Microstructural characterization is comprised of teChniques ranging from optical to transmission electron microscopy. Examination of the microchemistry includes energy dispersive xray analysiS and scanning Auger analysis. "1ethods of quantifying adhesion are also appl ied to these films for correl at ion wi th the process i ng parameters and compari son wi th other film deposition techniques.

(10: lOa .m.) ADHESION AND INTERFACIAL STUDIES OF PHYSICAL VAPOR DEPOSITED Cu FIlI>IS ON CERAMICS SLIlSTRATES: P. A. Scott and J. M. Rigsbee, Dept. of 'Ietallurgy, University of 11 ],nois, Urbana, IL. Cu films have been vapor deposited onto alumina and glass ceramic substrates by evaporation and plasma-aided physical vapor deposition. Relationships between coating adhesion and the nature of the ceramic/metal interface have been investigated as a function of the processing parameters. These resul ts wi 11 be presented.

(10:30 a.m.)

THE GROWTH OF METASTABLE ClJl_xCr~ ALLOY FILMS BY BIASED SPUTTER DEPOSITION: S. M. Shln, D. C. MCintyre, J. E. Greene and J. M. Rigsbee, Dept. of Metallurgy, University of Illinois, Urbana, I L.

Metastable CUl_lrx (0 < x < 1) alloys have been successfully produced by blased sputter deposition. The FCC Cu-rich films and BCC Cr-rich films typically grown at 75°C were both polycrystalline with an average grain size of < 1000 A. A CuCr metastable alloy phase diagram in terms of composition and growth temperature was made. Al so the effect of the bias on the morphology of the film was studied and this effect will be interpreted in terms of ion energy and ion flux.

(10:50 a.m.) CHARACTERIZATION OF ION PLATED ALLMINLM COATINGS ON SILICON*: H. S. Savage and J. M. Rigsbee, Dept. of Metallurgy, University of Illinols, Urbana, IL. Ion plating, a plasma aided physical vapor deposition process has been used to deposit Al onto Si. The effects of various deposition parameters (pressure, applied substrate bias, etc.) on the morphology of the coating and the nature of the coating/substrate interface have been studied. The microstructural techniques used include x-ray diffraction, SEM, EDX, TEM, SIMS and Auger. The results of this investigation wi 11 be presented. * The support of the Army Research Office, DAAG-29-83-K-OI51, is gratefully acknowl edged.

(11:10 a.m.) AN INTERFACE STUDY OF ION PLATED COPPER AND CHlOMILM COATlNGS*: J. C. Logas and J. M. Rigsbee, Dept. of Metallurgy, University of Il11nois, Urbana, IL. A pi asma enhanced physical vapor deposition techniques, ion plating, was used to produce copper and chromium coatings on nickel and copper substrates. Relationships between several processing parameters and the coating/substrate interfacial microstructure and microchemistry were sought. The effects of varying substrate bias, deposition pressure; solubil ity of evaporant in the substrate, substrate surface finish and predeposition surface cleaning by ion bombardment were characterized using scanning and transmission electron microscopy and Auger microchemical analysis techniques. * Thi s work was supported by the Army Research Office under contract DAAG-29-83-K-0151.

(11:30 a.m.) STRUCTURE/PROCESSING RELATIONSHIPS IN ION PLATED TITANILM*: D. M. Leet and J. M. Rigsbee, Dept. of Metallurgy, University of Il],nols, Urbana, IL. Ion plating of titanium onto aluminum and glass substrates in neutral (Ar) and reactive (N) environments was examined. The film morphologies were found to comply to the predicted Movchan-Demichishin zone types except for when appreciable impurities were present. The effects of substrate bias and impurity concentrations were related to film morphology. X-ray d iffrac t i on stud ies have shown that the preferred y rowth direction for Ti (011) and for TiN (111) is not strongly rei ated to the texture of the substrate. • ThlS work was supported by the Army Research Office under contract DAAG-29-83-K-0151.

TMS·AIME Annual Meeting Program. 105

TMS-SME JOINT SESSIONS

TECHNICAL PROGRAM WITH ABSTRACTS MONDAY, FEBRUARY 25, AM

MONDAY, FEBRUARY 25, PM

PROCESS MINERALOGY·METHODOLOGY

MINERAL PROCESSING AND EXTRACTIVE METALLURGY

(MPO/TMS) 9:00 AM

RHINELANDER NORTH (H)

2:00 PM

(MPO/TMS) RHINELANDER NORTH (H)

Chairmen: W. P. Petruk, CANMET, Ottawa, Ont., Canada P. R. Mainwaring, CAN MET, Ottawa, Ont., Canada

Chairmen: E. Martinez, Belle Mead, NJ O. McLean, Mohelumne Hill, CA

Electron Beam Techniques for the Analysis of Fine Particles in the Minerals Industry: N. Rowlands, McGill University, Montreal, PQ, Canada

Platinum Group Minerals and Their Recoveries from CopperNickel Bearing Duluth Gabbro: I. Iwasaki, P. W. Weiblen, P. J. Ryan, and K. J. Reid, University of Minnesota, Minneapolis, MN

The importance of mineralogical and chemical characterization of fine particles in the fields of mineral and metallurgical processing is discussed. Emphasis is placed on electron beam analysis techniques including electron diffraction and energy dispersive analysis with special reference to the scanning transmission electron microscope. The correct choice of instrument depending upon particle size. composition. and nature of sample is stressed and the analytical capabilities of different types of instruments are evaluated. Recent applications of electron beam equipment to processing problems are presented and the paper concludes with a review of new developments in the fields of surface analysis and micro-diffraction.

Precious metals are commonly believed to be recovered along with sulfide minerals in flotation but neutron activation analyses showed that the recoveries of gold arid silver were unexpectedly low. Recovery of PGM remain unresolved due to interferences in the analysis. These results indicate a need for re-evaluation of flotation procedures which have ignored special problems related to arsenide minerals. Electron microprobe, scanning electron microprobe and scanning auger microprobe analyses have identified Ni-arsenide minerals in the ore and confirmed a close association of PGM with the arsenide minerals as minute inclusions.

A Transformation Function for Liberation Analysis as Determined by Computer Simulations of Irregularly Shaped Particles: K. Baba, J. D. Miller, and J. A. Herbst, University of Utah, Salt Lake City, UT Liberation of valuable minerals from a gangue matrix during size reduction of multiphase particulate minerals is an important phenomenon in particle separation processes. Prediction of volumetric grade distribution from two dimensional linear probe image analysis has been studied using a transformation function to describe the degree of IiberatiCl1'1 of broken particles. Preliminary investigation has shown that the transformation function. derived from Monte Carlo simulations of irregularly shaped particles containing Irregularly shaped nuclei. mainly depends on the dispersion density I.e .• the number of nuclei per particle. and the volumetric grade. The relationship between the linear grade distribution and the volumetric grade distribution is written as: f(g) = f~ h (glg,Nn) p(g) dg where f(g). p(g). and h(g g. Nn) stand forthe linear grade distribution. the volumetric grade distribution. and the transformation function. respectively. Nn is the number of nuclei per particle, an Index ofthe dispersion density.

Relationship Between Observed Minerai Liberations In Screened Fractions and In Composite Sample: W, P. Petruk and R, G. Pinard, CANMET/MSL, Ottawa, Ont., Canada When determining mineralogical characteristics of ores In connection with minerai dressing, It Is necessary to measure the percentages of minerals that appear as free particles In polished sections of mill products. A study was conducted to determine whether the analysed minerai liberations would be different whon measuring a polIshed section of the entire sample than by measuring a saries of polished sections of screened fractions of the sample. Chemical compositions, modal analyses, and liberations for galena, sphalerite, and chalcopyrite were determined for a composite sample and for screened fractions of flotation feed of a fine-grained base metal ore. The analysed liberations were about 10% higher for data from screened fractions than for the entire sample.

Trace Sliver Analysis by Sims In Metallurgical Balances: S. Chryssoulis, Research and Productivity Council, Fredericton, N.B., Canada; B. Chauvin, University of Western Ontario, London, Ont., Canada; and L. J. Surges, Brunswick Mining and Smelting, Bathurst, N. B., Canada The ion microprobe, a form of SIMS, is presently one of the most sensitive instruments for the in-situ characterization of elemental distributions in phases of limited dimensions with detection limits in the parts per million range. The general utility of the ion microprobe has been hampered because of factors inherent to the technique and the instrument which make chemical quantitative measurements ~ifficult to obtain. The use of closely matching standards is the most widely recognized method for obtaining quantitative measurements. In this study, ion implantation was used for obtaining closely matching standards. The presence of trace, though frequently significant, amounts of silver in major sulphides open a new field of applications of quantitative SIMS in silver mineralogicallialances in beneficiation plants. Various aspects of quantitative SIMS measurements of Ag in sulphides are discussed.

An .Evaluation of Procedures for the Determination of Linear Grade Distributions in Liberation Analysis: C. L. Lin, J. D. Miller, J. A. Herbst, and K. Rajamani, University of Utah, Salt Lake City, UT Linear grade distributions determined from polished sections of randomly oriented particles can be used to estimate the extent of liberation for a particulate system. The measurement of linear grade distribution can be accomplished by both microprobe and optical image analysis. Both procedures were evaluated and compared using variable grade samples of flotation products from a copper ore. The statistical significance of the linear grade distribution data obtained by optical image analysis with the IBAS was assessed. The average chalcopyrite content of these samples, as determined by chemical assay, was used to estimate the variance of the experimental procedure. For a given precision, the number of particles required to obtain an unbiased representation of the sample was determined.

Utilizing Mineralogy In Process Development for Hecla's Lakeshore ProJect: T. S. Jordan, Montana Tech, Butte, MT, and W. A. Griffith, Hecla Mining Co., Wallace, 10 The Lakeshore Property in Pinal County, Arizona, contains two copper orebodles, one primarily oxides and the other, deeper deposit, primarily sulfides. The paper describes the manner in which sulfur and iron derived from the sulfide zone were utilized In processing the oxides.

Process Mineralogy of the Lucky Friday Process for Lead and Sliver Recovery from Lead Concentrates: H. D. Freeman, J. N. Hartley, and F. N. Hodges, Battelle, Richland, WA The Lucky Friday process consists of several unit operations: neutral roasting of the lead concentrate. ferric chloride leaching of the neutral roasted concentrate. brine leaching of the ferric leach residue. recovery of sliver and lead from the brine solution. and molten salt electrolysis of the lead chloride to produce high-purity lead. Work at Battelle has been associated primarily with the first four steps, with emphasis on optimizing sliver recovery. An Integral part of the process development work has baen the mineralogical examination of the lead concentrate and process residue. for each unit operation. This paper presents results of the mineralogical examination for a typical high-sliver lead concentrate. The relevance of the mineralogical information to the process development is also discussed.

Reflected Light Microscopy and Electron Microprobe Analysis of Feeds and Products from the Laboratory Flash Smelting of Copper Sulfide Concentrates: S. Pigno/et-Brandom and R. D. Hagni, University of Missouri-Rolla, Rolla, MO, and N. D. H. Munroe, Columbia University, New York, NY The complex reaction mechanisms which occur in pyrometallurgical processes may be identified by the study of the intergrowths of product phases with the reflected light microscope aided by the electron microprobe. For example. products from the flash smelting of copper concentrates are bleb shaped with hollow centers. have variable Cu/S ratiOS, and have rims of magnetite. These resulted from the conversion of chalcopyrite to copper sulfide and magnetite. Other reactions include the autogeneous conversion of pyrite to a phase with higher Fe/S ratios followed by the conversion to iron oxides.

106 - TMS-AIME Annual Meeting Program TUESDA~FEBRUARY2~AM

EXPLORATION (MPD/TMS) 9:00 AM

RHINELANDER NORTH (H)

Chairman: J. R. Craig, Virginia Polytechnic Institute and State University, Blacksburg, VA Ore Microscopy of the Boss-Bixby, Missouri Cobalt-Copper Iron Ores: R. T. Brandom and R. D. Hagni, University of Missouri, Rolla, MO The Boss-Bixby deposit differs from other Precambrian iron deposits in southeastern Missouri by its content of significant quantities of copper and cobalt, its greater titanium content, and its close relationship with a basic igneous intrusion. Ore micro~ scopic study of selected drill core samples has shown that the hypogene are minerals are magnetite, hematite, chalcopyrite, bornite, ilmenite, sphalerite, pyrite, and carrollite. Subsequent partial oxidation has formed martite, pseudo brookite, anatase, rutile, and covellite. Textural evidence indicates that two stages of iron and irontitanium oxide formation were followed by the deposition of the copper-iron sulfide minerals and carrollite.

Use of Pink Lepidolite and Tourmaline in Prospecting for Lithium at the Bonazars Lithium Deposit, Gois, Brazil: W, P. Petruk and D. B. Sikka, CANMET, Ottawa, Ont., Canada The Bonazars lithium deposit at Gois, Brazil contains 3 to 6 wt % liD,. Most of the lithium occurs in mica which varies from mauve through pink to colourless, and isassociated with black, pink, and green tourmaline. The colours of the mica and tourmaline are not directly due to the lithium contents of the minerals, but to the proportions of Fe 3 + to Fe 2 + and Mn 3+ to Mn2+. The high lithium micas vary from colourless to mauve but the most common ones are in the assemblage- mauve to pink mica and pink and black tourmaline. This assemblage can be readily recognized in the field and is a useful prospecting guide.

Petrographic Studies in Early Phases of Exploration for Gold: D. A. Lowrie and C. K. Wilton, Kerr Addison Mines Ltd., Toronto, Ont., Canada Environmental concerns and increasing mine development costs have created a need for early information on gold recovery from its host environment. The habit, assoCiation, and approximate abundance of minerals which contain unacceptable metallic ions which may be released during process of concentration of gold should be identified in exploration drill core. One case of a "clean" gold orebody is described to show that early petrographic studies contributed to a rapid decision to mine a small deposit by open pit and to custom mill the ore in an already restricted effluent environment. A second example describes identification of an undesirable mercury content and resulting action taken.

WEDNESDA~FEBRUARY27,AM

REFRACTORY AND ENERGY MINERALS (MPD/TMS) 9:00 AM

RHINELANDER NORTH (H)

Chairmen: R. D. Hagni, University of Missouri-Rolla, Rolla, MO C. A. Wert, University of Illinois, Urbana, IL Prospects for Lime Refractories in the Production of Metals and Ceramics: R. E. Moore, University of Missouri-Rolla, Rolla, MO The basic thermochemistry of decomposition and methods of stabilization of CaO materials are reviewed. CaO or lime refractories have recently received the most attention in Eastern Europe and in Japan. A number of products have had limited success and their applications are reviewed together with the various advantages they offer and disadvantages they pose for steel and ceramic industries. Difficulties related to the high tendency of CaO to hydrate have resulted in some novel methods to effect high densities; some of these may be useful in other basic refractory technologies.

Basic Refractory Mineralogy from Raw Materials to In-Service Corrosion: R. A. McCauley, Rutgers University, Piscataway, NJ The raw materials mineralogy of magnesite-chromite refractory brick are discussed as well as the development of the mineralogy during firing and its alteration during service. The compatibility of the various mineral phases is discussed with the use of phase equilibrium diagrams.

Microstructural and Chemical Alterations During the Burning of Periclase-Chromite Refractories: R. P. Stevens, A. P. Green Refractories Co., Mexico, MO The petrographic examination and electron probe microanalysis of the phases in fired periclase-chromite refractories are useful in the understanding of the physical properties of these materials. Considerable solid state elemental diffusion occurs between the major components (periclase and chromite), and a direct bond develops between them. The minor component (the Silicate) also contributes to integranular bonding. The placement, shape, and chemical compOSitions of the phases are descri bed in detai I.

THURSDAY, FEBRUARY 28, AM PAUL F. KERR MEMORIAL SYMPOSIUM I 8:30 AM

(MPD/TMS) RHINELANDER NORTH (H)

Chairmen: D. M. Hausen, Newmont Exploration Ltd., Danbury, CT O. C. Kopp, University of Tennessee, Knoxville, TN Paul Kerr's Contribution to Ore Discovery: L. J. Miller, Miller Exploration Co., Evergreen, CO Paul Kerr demanded of his students detailed geological observations, particularly in the field of mineralogy. It was Kerr's insistence on thorough evaluation of mineral assemblages that enabled his students to discover several major ore bodies. North Carolina phosphates were discovered by a Kerr student who recognized the importance of small amounts of uranium within the carbon particles tied to francolite. Further observations of the phosphate pellets lead to simplification of the ore dressing process and the development of marketable products. The Kidd Creek base metal deposit in Canada was also discovered by a Kerr student who mapped rhyolite ash flows and plugs within volcanic arc systems, a difficult task in a metamorphosed terrain with only 5% outcrop. Kerr's work at Marysvale. UT was remembered and helped in the recognition of the Kidd Creek fragmental ash flow and fractured dome. The economic geologist is constantly plagued by the problems of mineral identification in rocks of many environments. Kerr's students have been fortunate in having him as their teacher and he shares in the history of their ore discoveries.

Stability and Associations of Natural Tellurides: W. C. Kelly, E. J. Essene, and A. M. Affifi, University of Michigan, Ann Arbor, MI Occurrences and associations of natural tellurides are constrained by the relative fugacities of Te" 5" and O•. in specific mineralizing environments. Some are rare (eg., FeTe,) and others absent (eg., MoTe" ZnTe) in nature because high f-Te,Jf-5, ratios are rare or unattainable: whereas others (eg .• Ag, Te, HgTe) require lower ratios and are common. Complex and seemingly chaotic sulfide-telluride associations are, in fact. highly systematic and depend both on temperature and fugacity ratios. Some older sulfides act as buffers via reactions such as PbS + Te, ~ PbTe + 5" thereby affecting the deposition and paragenesis of younger tellurides and the combined or uncombined mode of occurrence of precious metals. Thermochemical calculations of telluride-sulfide-oxide equilibria can have pragmatic value. The thermochemical approach tells us little about the Te "source," but is beginning to unravel the systematics of telluride mineralogy and controls at the precipitational end of the line.

Uranium, Rare Earth, and Iron Mineralization in Pegmatite at the Bemco Mine Prospect, Cranberry Lake, New Jersey: A. H. Vassiliou and J. H. Puffer, Rutgers University, Newark, NJ The Bemco mine area is within the Precambrian igneous and metamorphic rock terrain of the New Jersey Highlands province. Rocks in the area include pyroxene/hornblende granite, quartz-oligoclase gneiss, and a pegmatite and its host rock, a lens of amphibolite which becomes a sulfide-rich pyroxenite near the ore zone. The are occurs along the hanging wall and footwall contact olthe pegmatite which was emplaced discordantly into the amphibolite-pyroxenite. A 7 cm thick ore zone, in contact with the pegmatite, is composed of a fine-grained matrix of magnetite (up to 76%). is rich in metamict zircon (up to 19%) and contains uranothorite (up to 9%) and fergusonite (up to 4%). A 25 cm thick zone, in contact with the pyroxenite, is essentially a magnetite ore (up to 92%) but it also contains accessory fergusonite and zircon. There are at least three plausible sources for the aqueous fluids that formed the ore-bearing pegmatite: metamorphic dehydration of the amphibolite; metamorphic dehydration of the quartz-oligoclase gneiss; late stage fluids from the granite magmas.

Mineralogy and Geology of Texaco's Hobson Uranium Deposit, Karnes County, Texas: H. M. Dahl and C. A. Callender, Texaco Inc., Bellaire, TX Texaco's Hobson uranium deposit occurs in the Deweesville Sandstone of the EoceneJackson Group. The host rock is a friable, fine-grained, well-sorted. highly porous, and permeable sand interpreted to be a beach deposit. Geometrically, the uraniumbearing zone resembles an elongated roll-front type deposit. The uranium mineralization occurs in the pores of the sand, as sand grain coatings and as replacements of sand-size and smaller grains and is commonly associated with pyrite and other opaque grains. Favored hosts for uranium appear to be clay aggregates, altered rock, and volcanic glass fragments, and carbonaceous plant debris. Aggregates of coffinite were identified by XRD and SEM/EDS analyses. Some uranium mineralization also appears to be dispersed and is postulated to be adsorbed on the clay and carbonaceous matter.

TMS-AIME Annual Meeting Program - 107 Pre-Ore Potassium Metasomatism, Creede Mining District, Colorado: P. M. Bethke, R. O. Rye, and P. B. Barton, Jr., US Geological Survey, Reston, VA Rhyolitic welded-tuff wall rocks of the epithermal base- and precious-metal veins of the Creede district were pervasively altered by the addition of more than two billion metric tons of potassium some 1.5-2 million years before mineralization. Sodium, cal. cium and magnesium were strongly depleted, yielding a nearly binary quartz + potassium feldspar asse",blage containing as much. as 13 weight % K,O. This large-scale metasomatl~m, originally noted by Steven and Ratte (1965), took place progressively by initial alteration of plagioclase phenocrysts to orthoclase or microcline followed byalteration of the ground mass feldspar to orthoclase and gradual change of the sanidine phenocrysts to more Or-rich compositions. Oxygen isotope and chemical studies show that the metasomatism resulted from the interaction of the tuffs with deeply circulating heated ground water and suggest that the potassium metasomatism of rhyolitic rocks IS

the facies eqUivalent of propylitization of volcanic rocks of more basic composition.

The Application of Cathodoluminescence Microscopy to the Study of Sparry Dolomite from the Viburnum Trend, Southeast Missouri: R, L. Voss, Cominco American Inc., Bixby, MO, and R. D. Hagni, University of Missouri-Rolla, Rolla, MO Sparry dolomite from all of the operating mines in the Viburnum Trend of Southeast Missouri have been found by cathodoluminescence microscopy to reveal a systematic pattern of banding resulting from a growth zoning within individual dolomite rhombs. Four principal bands have been recognized throughout the entire Trend and each of the major bands contain even finer internal banding. Minor bands a few microns in width can be correlated in specimens collected ten's of miles apart along the trend. The first three principal dolomite bands decrease from south to north. This feature, together with the fact that the white sparry dolomite crystals decrease in abundance from south to north in the Trend, suggests that a major source for the fluids was from the south. The application of cathodoluminescence microscopy to crystalline dolomite demonstrates a strong correlation between ore grade and the intensity of internal

THURSDAY, FEBRUARY 28, PM PAUL F. KERR MEMORIAL SYMPOSIUM II 1 :20 PM

RHINELANDER NORTH (H)

Chairmen: D, M, Hausen, Newmont Exploration Ltd., Danbury, CT O. C. Kopp, University of Tennessee, Knoxville, TN Significance of Clay Mineralogy in the Amenability of Sandstone Vanadium Ores: D. M. Hausen, Newmont Exploration Ltd., Danbury, CT The amenability of a given vanadium ore to treatment depends largely on the mineralogic combinations of vanadium in the ore. Quantitative data on vanadium min-

eralogy provides a basis for selection of proper treatment and may eliminate many timeconsuming amenability studies. Vanadium is distributed through the interstices of mineralized sandstone as oxidized vanadates, reduced oxides, and silicates. Oxidized vanadates (carnotite, tyuyamunite, etc.) are most readily beneficiated by acid leaching. Reduced Oxides are Slowly solubilized by most acid treatments. Layered silicates, roscoelite, mixed-layer mica-montmorillonite. and chlorite are common to sedimentary

deposits and are least amenable to acid extraction. Vanadium is combined principally as layered silicates in the clays of many sandstone ores. Mineralogic studies in this paper are largely confined to clay minerals and their amenability characteristics in low pH liquors.

banding and dissolution textures.

Clay Mineralogy of Insoluble Residues in Marine Evaporites: M. W. Bodine, Jr., US Geological Survey, Denver, CO

Preliminary Comparison of the Geochemistry of limestones and Dolostones Adjacent to Mineralized and Non-Mineralized Breccias: O. C. Kopp, T. B. Crattie, and D. R. Owen, University of Tennessee, Knoxville, TX

Insoluble residues from three sequences of Paleozoic marine evaporites (Retsof salt bed in western NY, Salado Formation in southeastern NM, and Paradox Member in southeastern UT) are rich in trioctahedral clays. Chlorite (clinochlore), corrensite (mixed-layer chlorite-trioctahedral smectite), talc, and illite (the only dioctahedral clay) are the dominant clay minerals; serpentine, discrete trioctahedral smectite (saponite), and interstratified talc-trioctahedral smectite are sporadically abundant. These claymineral assemblages differ chemically and mineralogically from those observed in

Whole-rock analyses of limestones, fine-grained dolostones, and coarser-grained dolostones adjacent to mineralized breccias (Coy mine, Mascot-Jefferson City district) are compared with similar lithologies adjacent to non-mineralized breccias at the new Thorn Hill section located 50 km NE of the Coy mine. Specimens were analyzed for Ca, Mg, Si, AI, K, Fe, Mn, Sr, Br, CI, S, Ti, and P using X-ray fluorescence analysis. The concentrations of the major and most minor elements for Thorn Hill specimens fall within the range of concentrations for Coy mine specimens; however, several differences were noted. Significant differences (P < 0.05) were noted for Fe, CI, and Br for finegrained dolostones and for MgO, Fe, and Mn for the coarser-grained dolostones. No significant differences were detected for the limestones from both areas.

The Zinc-I ron-Manganese Ore Bodies of Franklin and Sterling Hill, Sussex County, New Jersey: R, W. Metsger, The New Jersey Zinc Co., Ogdensburg, NJ The metamorphic zinc-iron-manganese ore in the Grenvillian rocks olthe Reading Prong in Sussex County, f':IJ, is unique. The singularity of its mineral composition and associations has fueled controversy among economic geologists and mineralogists for more than a hundred years. The silicate-oxide ore, in two synformal concentrations, has been mined since about 1838. The Franklin mine was depleted in 1954 while the one at Sterling Hill is still producing. Although the two mines are perhaps best known for their almost three hundred mineral species and have been a mecca for collectors, they-as importantly-have provided a window through which to observe more than a billion years of geologic history. When pieced together, studies reveal a sequence of probable sedimentary deposition, intense folding, pseudo-viscous flow with attendant negative diapirism, uplifting, erosion, karstification, hydrothermal alteration, burial, faulting, igneous intrusion, uplift, saprolitization, and glaciation.

Ore Microscopy and Genesis of the Copper-Shale Deposit at Creta, Oklahoma: R. D. Hagni, University of Missouri-Rolla, Rolla, MO, and D. E. Gann, Milsaps College, Jackson, MS Ore microscopic study of copper-bearing shale at the Creta mine in southwestern Oklahoma reveals a variety of copper sulfide grains and shows that each has originated by replacement of original constituents in the Creta shale. The largest grains, about 120 /Lm in diameter, are replacements of megaspores with triletes morphology. Their interiors are shown by Auger microprobe analyses to be organic matter replaced by chalcocite; the spore exines have been replaced by chalcocite and djurleite. Digenite and minor chalcocite replace collomorphic pyrite averaging 40/Lm in diameter. Grains 10 /Lm or less in diameter are mostly euhedral, six-sided, platy copper sulfide pseudomorphs after pyrrhotite or after octahedra and cubes of pyrite. The results of this study indicate that the copper minerals are epigenetic and were deposited from fluids introduced into the Creta shale when it was relatively uncompacted and permeable. The shale served as a favorable reducing environment that contained a source of sulfur in the form of pyrrhotite and pyrite.

most continental and normal marine rocks. which commonly contain kaolinite. diocta-

hedral smectite (beidellite-montmorillonite), illite, mixed-layer illitedioctahedral smectite. and. in most cases, no more than minor quantities of trioctahedral clay minerals.

The distinctive clay mineralogy in these evaporite sequences suggests a largely authigenic origin. These clay minerals are thought to have formed during deposition and early diagenesis through interaction between argillaceous detritus and Mg-rich marine evaporite brines.

Paul Kerr on Sensitive Soils and Quickclays: I. J. Smalley, University of Waterloo, Waterloo, Ont., Canada Paul Kerr's paper on Quick Clay (1963) is probably the most widely read paper on quickclay ever published. Quickclays are extremely sensitive soils. The "sensitivity parameter" is obtained by dividing the undisturbed shear strength by the remoulded shear strength. If a value greater than 50 is obtained, then the soil can be classified as a quickclay. True quickclays are characterized by remolded strengths of the orner of 0.5 kPa. Classic quickclays are found in Scandinavia and Eastern Canada. Kerr and Drew discussed the large quickclay deposit underlying Anchorage in a classic paper (1968). Kerr's views on quickclays were perhaps most clearly expressed in a paper with Lieblir,g (1965) which described the major critical conditions which contribute to quickclay movement. There is still discussion and disagreement about the nature of quickclays and the mechanism of quickclay slides. The clay mineral-based views favored by Kerr still find support although an alternative, "primary mineral" view suggests that it is the finely ground primary minerals which determine quickclay properties and that a very small amount of clay mineral material is required.

Mineralogy of Some Egyptian Bentonitic-Clay Deposits: A. K. Attia and S, N. Boulis, National Research Centre Dokki, Cairo, Egypt A broad reconnaissance program on bentonitic clays in Egypt has been carried out and the means of identifying and assessing the basic characteristics of these deposits which promote their use as industrial raw material have been conducted using X-ray diffraction, differential thermal analysis, and electron microscopy. Samples were collected from a number of localities, including Qasr EI-Sagha (Fayum), Cairo-Alexandria Desert Road (Western Desert), and Kattamiya area (Eastern Desert). This paper attempts to explain the mineralogical and chemical characteristics of these deposits.

Progress in High Pressure-Temperature Mineralogy: W. A. Bassett, Cornell University, Ithaca, NY Intense X-rays from the Cornell High Energy Synchrotron Source (Chess) make it possible to study phase transitions by "real-time" X-ray diffraction. A diamond anvil cell equipped with a resistance heater has been used to produce pressures up to 350 kbar and temperatures up to 800"C. USing these techniques, we have shown that the high pressure phase transition in fayalite proceeds by a coherent restacking mechanism when subjected to conditions in the diamond cell. Very intense infrared from a Q-switched YAG laser is used to achieve temperatures in excess of 4000'C in high pressure samples in a diamond anvil cell. Electron microscopy is used to examine the effects in the samples after removal from the diamond cell. Using these techniques we have been able to melt diamond and examine the properties of the quenched melt.

108 - TMS-AIME Annual Meeting Program Characterization of Titanium Diboride: W. J. Croft and R. J. Arnott, Army Materials and Mechanics Research Center, Watertown, MA A series of commercial titanium diboride powders have been characterized in terms of X-ray crystallography, composition, particle size distribution, and particle shape. These materials were used in sintering experiments from which the effect of impurities on the sintering temperature was observed. Transmission electron microscopic observations have been made on ion milled and chemically milled hot pressed material. Dislocations have been observed as well as grain boundary phases. Limited bondng between grains seems to account for poor mechanical properties. Observations have been made of preferred crystallographic orientation in hot pressed material.

Ore.ld, A Microcomputer Program for the Rapid Identification of Opaque Minerals in Ores and Beneficiation Products: J, E. Hagni, Delta Research Corp., Arlington, VA, and R. D. Hagni, University of Missouri-Rolla, Rolla, MO ORE.lD rapidly searches a data base of the principal properties of about SOO ore minerals. Searches may be performed on any or all of the following properties: Vickers hardness, Talmage hardness, average reflectance, strength of anisotropism, and principal colors and tints of the rnineraland its internal reflections. Data frorn the International Mineralogical Associatioi1-Commission on Ore Microscopy data card file have been used when available. The program displays the number of data matches for each mineral found, displays their chemical components, and allows the range parameters to be narrowed or broadened for each of the identification properties for repeated searches, if desired. ORE.ID is much more rapid, allows for the use of more identification properties, and involves more ore minerals than any previous identification system.

PAUL F. KERR MEMORIAL SYMPOSIUM DINNER WHAT:

The Process Mineralogy Committee of AIME and students of Paul F. Kerr are sponsoring a symposium dinner.

WHEN:

7 p.m., Thursday, February 28.

COST:

The dinner is $25 per person, with an open cash bar.

WHERE:

The Faculty House of Columbia University, 400 W. 117 St., New York, NY.

WHO TO CONTACT FOR FURTHER INFORMATION: Andreas H. Vassiliou, Geology Dept., Rutgers University, Newark, NJ 07102, (201) 648-5100.

MAKE YOUR RESERVATIONS NOW!

TMS-AIME Annual Meeting Program - 109

INDEX TO AUTHORS AND SESSION CHAIRMEN A Aalbu, J. 4 Abbaschian, G.J. 38 Abdel-Aziz, A.-H. K. 66 Abdel-Gwad, E.A. 92 Abeln, S. 38 Adam, C.M. 12 Adams, RG. 37 Agarwal, J.C. 25, 42 Ahearn, J .S. 60 Ahlers, M. 42 Ahn, J. 14 Ahuja, R 15 Ai, D.K. 49 Airey, G.P. 60 Akben, M.G. 57,85 Akeret, R 60 Alam, A. 76 Alam, M. 25 Alarcon, V. 65 Albaharna, O. 31 Ali, S. 71 Altman, R. 11 Altstetter, C.J. 54 Alqasmi, RA. 42 Ammann, P.R 22 Andersen, T.N. 35 Anderson, C.W. 41 Anderson, D. 85 Anderson, I.E. 70 Anderson, RJ. 76 Andrews, J.B. 97 Andrews, RN. 72 Angers, L. 73 Anjier, J.L. 34,48,93 Ankem, S. 18 Antolovich, 39 Antonioni, T.N. 9 Apelian, D. 15, 40, 71, 78 Arai, K.1. 43 Arey, B.W. 55 Argyropoulos, S.A. 31 Arlyuk, T.A. 77 Armstrong, RW. 6 Armstrong, J.A. 85 Arora, O. 18 Arora, V.D. 98 Arsenault, RJ. 4,5,21,56 Asao, H. 9, 24 Asaro, RJ. 44 Atteridge, D.G. 55 Attia, Y. 55 Aune,J.A. 9 Aust, K.T. 12 Awerbuch, J. 41 Ayer, R. 17 Ayers, J.D. 70

B Backmann, J. 94 Backer, G. 40 Baeslack, W.A.lII 3,18,33,55 Bagheri, H. 51 Bagshaw, A.M. 62 Bailey, K.L. 24, 72 Baily, A.C. 6 Baker, I. 53 Balaguer, J.P. 40 Ball, D. 35 Ball, D.J. 55 Bandy, R 54 Banerjee, D. 102 Banerji, K. 82 Ban-Ya, S. 9, 23 Baradel, A. 102 Barbaro, M. 101 Barbucci, R. Barker, E.L. 61 Barrera, R. 67 Battle, T.P. 23 Bauer, J. 23 Bautista, R.G. 6, 22, 84

Baxter, W.J. 3 Beck, P.A. 30 Becker, A.J. 77 Beckstead, L.W. 84, 85 Belitskus, D. 49 Bellows, RS. 74 Belton, G.R 25 Bendersky, L.A. 70, 75 Benn, F.W. 50 Benn, R.C. 70, 101 Bennett, L.H. 11, 89 Bercovici, S.J. 78 Berko, S. 72 Berkowitz, B.J. 17 Bernstein,I.M. 81,99 Bessard, J.C. 48 Betrabet, H.S. 10 Bevk,J. 5 Bharucha, N.R 6 Bhattacharya, RS. 61 Bhattacharyya, S. 99 Bhappu; RR. 50 Biederman, RR 75 Bildstein, J. 78 Bilello, J. C. 39, 54 Birnbaum, H.K. 54 Blake, RA. 41 Blakely, J.M. 77 Blanc, J.M. 48 Blanco, J.A. 9 Blaser, M. 35 Blayden, L.C. 8 Block-Bolten, A 33 Boettinger, W.J. 70, 75 Boivin, RF. 49 Bolstad, D.A. 3 Bonds, S.M. 56 Bopp, A.F. 23 Borg, P. 4 Boring, M. 12 Bornand, J.D. 78 Bomstein, N.S. 75 Borotka, J.C. 79 Borowiec, K. 11 Borzick, W.J. 65 Bouffard, J.P. 81 Bourell, D.L. 44, 63, 64 Bowden, D.M. 3 Bowen, H.K. 17 Bowker, J.T. 102 Bowman, K.A. 42 Boxall, J.M. 99 Braid, J.E.M. 66 Brandtzaeg, S.R 34 Brasher, D. 47 Bray, D.J. 56 Breneke, P. 63 Bresnahan, K.M. 96 Brierly, C. 55 Brierly, J. 55 Briggs, D.A. 81 Brimacombe, J .K. 15, 68 Brocchi, E.A. 102 Broderick, T.F. 56 Brooks, A. 60 Brooks, J. 14 Brown, L. 67 Bruemmer, S.M. 45, 55, 60, 76 Bruenig, T.M. 83, 98 Bruno, J.D. 84 Brupbacher, J.M. 23 Bruynesteyn, A. 29, 55 Buchta, W.M. 20 Buck, O. 5 Bui, RT. 5 Bullough, V.L. 7,23,95 Burkat, V.S. 8 Burke, M.A. 40 Bush, J.F. 23 Bush, RW. 14 Bustos, A.A. 68 Butler, RF. 37 Butrymowicz, D.e. 72 Buttinelli, D. 50 Buxmann, K. 78 Bylina, N.J. 80

c Cahill, P.L. 47 Cahn, J.W. 72,89 Caiazzo, F. 96 Calderwood, F.W. 57 Calhoun, K.J. 37 Campbell, P.G. 20, 34, 49, 62, 95 Canova, G.R. 44 Cao, X 53 Caplan, I.L. 47 Carlson, O.N. 9 Carnahan, T.G. 6 Carneiro, R. 49 Carro, G. 97 Carter, W.B. 103 Casey, M.E. 79 Castillehos, A.H. 11i Castonguay, L. 95 Caufriez, A. 99 Caulfield, T. 74 Cavalli-Bjorkman, E. 69 Chadwick, B.K. 36 Chagina, T.S. 8 Chaiko, D.J. 90 Chakrabarti, D.J. 57 Chama, C. 56 Chan, B. 11 Chan, K.S. 18 Chan, T.C. 45 Chang, G.M. 103 Chang, K-M 27, 80 Chang, P.-H. 14 Chang, S.-.1. 82,83 Chang, Y.A. 8,42,57,84 Chang, Y.W. 15, 51 Chapman, T.w. 22, 35, 50 Charette, A. 95 Chase, C.K. 37 Chaubal, M. 19, 93 Chaubal, P.C. 67, 72 Chellman, D.J. 39 Chen, C.H. 98 Chesnutt, J.C. 27 Cheverton, RD. 39 Chi, C.S. 53, 56, 102 Chia, E.H. 69, 86 Chia, M.S. 22 Chia, T.W. 15, 51 Chilton, J.P. 22 Chin, L. 19, 93 Cho, S.J. 100 Choi, Y.U. 65 Chou, E.C. 84, 85 Chou, Y.T. 10,98 Christman, T. 13 Chuang, Y.-Y. 42 Chu, S.N.G. 52 Chung, Y.R 92 Chung, W.B. 93 Chynoweth, J. 97 Cieslak, M.J. 79 Cigan, J.M. 69, 101 See addenda/Non Ferrous Cinq-Mars, RJ. 42 Claessens, P.L. 6 Clark, B. 17 Clark, K.G. 69 Clark, W.A.T. 10, 96, 97 Clauer, A.H. 87 Clayton, C.R. 60 Clomenares, C. 91 Closset, B. 31 Clough, S.P. 60 Clum, J.A. 29, 55 Clumpner, J.A. 96 Cohen, J.B. 21 Cohen, M. 26 Cole, E.R 69 Cole, J.F. 99 Collier, J.P. 73 Collins, L.E. 63 Collur, M. 25 Colmenares, C. 91 Conochie, D.S. 24

Conrad, H. 98 Conti, C. 78 Conway, M.H. 37 Cook, G.M. 6, 22, 49 Cooke, A.V. 20, 22 Cooper, A.H. 80 Cooper, D.M. 29 Corbett, J.W. 37 Corbiau, J.L. 99 Cosandey, F. 27 Couderc, P. 21 Coulon, J.P. 7 Couper, M.J. 38 Courtney, T.H. 100 Coyle, RJ. Jr. 33 Crane, J. 96 Crawford, G. 63 Creel III, J .M. 37 Crompton, J.S. 83, 99, 102 Cromwell, J. 6 Cruells, 101 Cruz, A. 77 Cukier, S. 21 Culbertson, G.C. 44 Curreri, P.A. 92 Custovic, E. 24 Cutshall, E.R 7, 95 Cuzmar, J. 35 Czajkowski, J. 39

D Daeubler, M.A. 99 Dahmen, U. 72, 78 Dalder, E. 54 Daniels, J.A. 67 D'Antonio, C. 21 Danyluk, S. 89, 97 Darmann, C. 58 D Arora, V. Da-rum, F. 43 Das, RP. 7 Das, S.C. 7 Das, S.K. 42 Davenport, W.G. 50 Davey, T.R.A. 11 David, S.A. 14 Davidson, RD. 79 Davis, S.A. 14 Davis, B.E.C. 17 Davis, G.D. 60 Davis, L.A. 53 Davis, RF. 32 Dayananda, M.A. 79 Dean, D.C. 78 De Bango, E. 49 DebRoy, T. 15, 25, 51 de Fontaine, D. 12, 17 De Iorio, I. 5, 96 de Lanerolle, N. 78 Dell, M.B. 62 Demopoulos, G.P. 51, 68 Dempsey, J.P. 84 Dempsey, M.D. 81 DeNale, R 33 Denney, P.E. 14, 18 Denzer, D.K. 39 Derdacka-Grzymek, A. 19 Dernedde, E. 95 Desclaux, P. 49 Dewing, E.W. 94 Diebold, G.E. 90 Dienes, G.J. 30 Dimayuga, F. 63' Djennas, F. 92 Dokiya, M. 20 Domic, E.M. 90 Domingue, J.A. 74 Don, J. 89 Doutre, D. 63 Doychak, J.K. 76 Doyle-Gamer, F.M. 84,90 Drouven, B. 31 Dube, G. 63 Dubreuil, A.A. 63

110 - TMS-AIME Annual Meeting Program Duby, P.F. 36, 49, 50 Dudorova, V.S. 8 Dunlop, G.L. 22 Dunn, G. 14 Duprat, M.G. 7 Duquette, D.J. 66, 80 Duszczyk, J. 88 Dutrizac, J.E. 68

E Eagar, T.W. 14, 33 Early, J.G. 70 East, F. 61 Eckert, C.E. 78 Edgecumbe, T.S. 17 Edmonds, K. 17 Edwards, G.R 3 Egan, J.J. 42 Eichelman, G.E. 47 Ek, C. 29 Ekenes, J.M. 95 El-Hebary, M.R 92 El-Kaddah 15, 71 Elliott, J.F. 25, 45, 46, 52, 92, 93 El-Salamoni, M.A. 92 El-Sawy, A.H. 92 Elsner, D. 19 Embury, J.D. 44 Epstein, S. 23 Era, A. 94 Erdemir, A. 103 Erickson, G.L. 74 Eriksson, S. 69 Ettel, V.A. 6 Evans, A.G. 31 Evans, J.W. 25,30,48,50,69 80 Eylon, D. 53, 56

F Falicov, L.M. 12 Fang, T-T. 4 Farias, L.R 71 Farkas, D. 33 Faulkner, J.s. 12 Faunce, J.P. 96 Fautrelle, Y. 15 Feng, C.R 5, 99 Ferguson, P. 78 Fernandez, R 19 Fiedler, L.J. 64 Field, RD. 39, 88 Filho, A.C.B. 62 Fine, M.E. 73, 99 Finel, A. 12, 17 Fior, G.O. 6 Fischer, W.K. 20 Fisher, D.M. 27 Fisher, RM. 28, 73, 78 Fishman, S.G. 41 Fiske, M.R 92 Fleischer, G. 24 Fleming, RE. 61 Fletcher, M.R 72 Flinn, J.E. 26 Flint, J.H. 22, 81 Flom, Y. 56 Floyd, J.M. 24 Foiles, C.L. 30 Follin, S. 55 Fong, M.C. 49 Foot, D.G. Jr. 50 Forberg, H. 37 Ford, F.P. 16 Forsen, O. 68 Fort, K. 34 Fosnacht, D.R 24, 83 Foster, J.S. 66 Fournelle, RA. 73 Frank, RA. 52 Frank, RC. 79 Frankenfeldt, RE. 7

Frankel, G.s. 82 Fraser, H.L. 39, 53, 70, 88 Fray, D.J. 22,37,46 See addendalThermo I Frenay, J. 29 Friedman, G.1. 44 Froes, F.H. 3, 27, 47, 53, 56, 75 Froisland, L.J. 42 Fruehan, RJ. 23, 26, 45, 52 Fuerstenau, D.W. 101 . Fujishige, M. 20 Fujishima, O. 4 Fujita, H. 103 Fukushima, K. 9 Fulford, G.D. 61 Fultz, B. 6, 103 Funkenbusch, A.W. 75

G Gabb, T.P. 80 Gallois, B. 32 Gameiro, D.H. 102 Gandhi, C. 64, 70 Gangloff, RP. 66, 82, 98 Gariepy, B. 63 Garlick, RG. 73 Garrison. Jr .. W.M. 83. 85 Gauckler, L.J. 78 Gawlicki, M. 19 Gayda, J. 80 Gayle, F.W. 38, 87 Gebeau, RC. 46, 73 Gee, J.T. 20 Gehlback, RE. 20 Gelles, D.S. 67 Gentner, D.H. 39 Gerlach, J. 77 German, RM. 75,87, 100 Geskin, E.S. 9 Gettinger, G.W. 22 Ghosh, A.K. 64, 70 Giamei, A.F. 26 Gianetto, J.A. 66, 102 Gibeling, J.C. 4 Gibson, D.N. 85 Gibson, RF. 13 Gibson, S.J. 34 Gilman, J.D. 54 Gilliland, J.C. 7 Ginatta, U. 69 Giroux, S.M. 59 Gladman, T. 14 Glasgow, T.K. 26 Glaws, P.C. 23 Glicksman, M.E. 28, 74, 75 Goddard, J.B. 101 Goel, RP. 11, See addenda! Kellogg, Thermo Gokcen, N.A. 6,8,23 Goktepe, M. 35 Goldstein, J.1. 54, 78 Gopalakrishna, K. 7 Gopienko, G.N. 77 Gould, J.E. 3 Grabke, H.J. 75 Grabowski, K.S. 103 Grant, N.J. 38 Gray, N.B. 10 Greene,J.E. 104 Griffin, J.A. 56 Griffith, W.M. 32, 39, 75 GIjotheim, K. 19, 62 Grobner, P.J. 16 Gronsky, R 10 Groomes, D.O. 32 Groves, RD. 59 Grzymek, J. 19 Gschneidner, K.A. Jr. 57,89 Gudenau, H.W. 65 Guerriero, R 102 Gundiler, I.H. 101 Guthrie, J.D. 34 Gutierrez, E. 40 Guyer, K.L. 60 Guzman, M.E. 26, 46 Guzman, S.S. 11

H Haas, L.A. 29, 55 Hack, J.E. 18 Hackl, RP. 29 Hadlet, D. 63 Hager, J.P. 24, 67 Haggarty, J.S. 80 Hale, W.R 62 Hales, C. 99 Hales, S.J. 88 Halicioglu, T. 29 Hall, J.A. 47 Hall, P.G. 6 Haller, W. 78 Halloran, J.W. 88 Halsall, P. 85 Hammond, J.s. 60 Han, M.K. 68 Hancock, H.A. 37 Handa, V. 71 Handwerker, C.A. 10 Hanson, J. 101 Harbison, B.B. 91 Hare, A. 47 Harf, F.H. 74, 86 Harlan, RL. 7 Harnish, C. 7 Harrington, D.A. 60 Harris, K. 74 Harris, R 63 Hartley, J.N. 6 Harvey, W.W. 22, 49 Hashimoto, K. 81 Hasson, D.F. 3, 18, 33 Hatherly, M. 44 Haupin, W.E. 62 Hawkins, G.F. 41 Hawkins, R 16 Heaney, J.A. 79 Hebsur, M.G. 88, 89 Hegde, V.S. 25 Helling, D.E. 44 Hemker, K.J. 80 Hendrix, J.L. 37,51 Henein, H. 30, 40, 71, 90 Hens, K. 65 Herbertson, J. 63 Herlitz, H.G. 69 Hertzberg, RW. 83, 86, 99, 102 Hettula, E. 68 Heubaum, F. 99 Hickey, G. 98 Hick!. A.J. 100 Hildeman, G.J. 39 Hill, S.D. 58 Hill, V.G. 19 Hillery, H.F. 60 Hills, C.R 79 Himmelblau, C.D. 44 Hinds, S.A. 19 Hirano, M. 10 Hirano, T. 93 Hirth, J.P. 10, 82, 91 Ho, M. 20 Ho, P.S. 30 Hockman, RF. 103 Hoff, J.C. 63 Hoffmann, J.E. 58,80 Hoffman, RR 24 Hoh, Y.C. 22 Holbrook, J.H. 16, 29 Holman, J.B. 42 Holman, J.L. 58 Holzworth, T. 7 Hornack, T.R 77 Horng, J.-L. 73 Houston, G.J. 35 Howell, P.R 10, 13, 22, 56, 72, 73 Howie, B.J. 36 Hoyt, J.J. 17 Hsieh, H.P. 94 Hsieh, K-C 84 Hsu, S.C. 102 Hu, D-C. 46 Hu, H. 43 Hu, S.M. 38

Huang, F.H. 67 Huang, S.C. 26,27,80 Hubbard, A.T. 60 Hudson, E.K. 69 Huggins, D.K. 85 Huh, T. 69 Huiatt, J.L. 50 Huni, J.P.R 49 Hunt, W.H. Jr. 56 Hunter, G.B. 33, See addenda! Titanium III Husain, K. 19 Hussain, M. 101 Hussien, S. 13 Hwang, C. 81 Hwang, C.M. 17 Hwang, S.K. 60 Hwang, W.-S. 15

I Igarashi, T. 24 Iguchi, Y. 9, 23 Iida, Y. 58 1m, H.B. 58 1m, S.J. 65 Imam, M.A. 18 Inagaki, K. 65 Inal, O.T. 28, 101 Inoue, T. 4 Irissarri, A.M. 70 Irons, G.A. 40, 71 Isaacs, J .A. 93 Ishii, F. 9, 23 Ishii, Y. 24 Ishwar, V.R 64 Ito, Y. 58 Iwasaki, I. 29

J Jaccard, R 99 Jacko, RJ. 60 Jackson, A.G. 75 Jackson, M.R 26,74 Jacob-Duliere, M. 78 Jacobs, S. 48 Jacobson, L.A. 71 Jauvin, A. 4 Jayaraman, N. 67 Jeffcoat, W.H. 61 Jena, P.K. 7 Jenkins, D.H. 19 Jha, M.C. 50,.83 Jibiki, K. 35 Jin, S. 89 Jin, Z-M 30 Jiricny, V. 69 Jochem, I. H-O 96 Johnson, A.R 94 Johnson, D.D. 12 Johnson, D.L. 18 Johnson, D.L. 82 Johnson, W.C. 79 Johnston, T.J. 77 Johnston, W.D. 52 Jones, RL. 54 Jones, W.D. 68, See addenda Jones, W.B. 27 Jong, B.W. 58 Jongenburger, P. 88 Jordan, A.S. 52 Joshi, A. 32, 45, 60, 76 Ju, C.P. 98 Judd, RR 43 Judin, V.P. 84 Judy, RW. Jr. 18 Juhas, M. C. 96 Jung, D.Y. 60 Jung, Y.H. 13, 39 Jurges, C.J. 95 Juric, D. 63

K Kaenel, RV. 48 Kahn, L.R 30

TMS-AIME Annual Meeting Program - 111 Kaiser, D.L. 92 Kaiura, G.H. 24 Kalpoe, R 19 Kaluzhsky, N.A. 62 Kameda, J. 98 Kamdar, M.H. 16 Kamenetzky, E.A. 10 Kameyama, T. 20 Kamio, S. 10 Kammel, H.C.R 24, 35, 36 Kandemir, H. 29 Kandra, J. 27 Kane, RL. 47 Kang, S.K. 70 Kang, T. 71 Kamowsky, M.M. 73 Karov, J. 17 Kalje, F.G. Kattamis, T.Z. 92 Katz, RN. 47 Keane, J.M. 37 Keefe, P.W. 73 Keller, F. 95 Kellogg, B.C. 9 Kellogg, H.H. 11 Kembaiyan, K.T. 32 Kemori,N. 9 Kerans, R.J. 10 Kerby, RC. 36 Khalafalla, S.E. 50, 84, 92 Khan, P.A.A 25 Khobaib, M. 97 Kibrick, M. 44 Kikuchi, R 30 Kilaas, R. 10 Kim,B.W. 28 Kim, D.S. 65 Kim, H.J. 103 Kim,H.J. 92 Kim,J.S. 65 _Kim, N.J. 64, 66 Kim, S-H 90 Kim, S.K. 65 Kim Y. 89 Kim, Y.G. 58 Kim, Y-H 11 Kim, YoW. _57 Kim, Y.-W. 27, 32, 75 Kimerling, L.C. 37,53 Kimmerle, W.L. 5 Kimura, H. 13, 53 Kimura, T. 24 King, A.H. 102 King, E.B. 85 King, W.E. 6 Kipouros, G.J. 81 Kircher, T.A. 64 Kirchoff, S. 97 Kleek, J.J. 27 Klein, C.F. 17 Kleppa,O.J. 42 Knipe, RK. 104 Knustad, O. 22, 86 Koch, C.C. 12 Koch, V.R. 81 Kocks, V.F. 44 Koczak, M.J. 100 Koegel, D. 92 Kohno, H. 24 Kohsaka, Y. 102 Kolodin, E.A. 20 Komanduri, R 59 Kondos, P. 68 Konik, Z. 19 Konitzer, D.G. 53,88 Kopa, R. 103 Kor, G.J.W. 45 Korbel, A. 44 Kordosky, G.A. 37 Korth, G.E. 26 Kossowsky, R 14, 103 Kou, S. 91 Koziol, J .K. 80 Kramer, I.R. 4, 5, 99 Krebs, B. 84 Kremer, H.A. 21 Krishnamurthy, S. 53 Krueger, J. 24 Krumpelt, M. 49

Kubo, K. 92 Kudryk, V. 11 Kujanpaa, V.P. 14 Kulik, J. 12 Kumar, P. 100 Kuschel, G. 62 Kvande, H. 62 Kwok, C. 98 Kwok, T. 30

L Labun, P.A. 76 Lad, R.J. 77 Laher, T.M. 20 Lam, RK.F. 93 Lambers, E.S. 66 Lammers, M. 56 Lan, W. 59 Landau, V. 36 Landers, J. 33 Landolt, C.A. 9 Langa, J.M. 48 Langenbeck, S.L. 39 Langford, G. 59 Lankford, J. 66, 83 Lanotte, L. 5 LaPointe,J.L. 33,Seeaddenda! Titanium III Laraia, V.J. 79 Larson, A.H. 69, 101 Latanision, RM. 82 Laughlin, D.E. 57 Launois, H. 52 Lawley, A. 12, 100 Lawrence, RW. 29 Laxmanan, V. 4092 Le, T.D. 81 Le, Y. 91 Leatherman, G.L. 75 Lederich, RJ. 38,40,88 Lee, A.Y. 69 Lee, E.W. 64 Lee, H.C. 48 Lee, H.G. 58 Lee, M.C. 45,See addenda! Thermo I Lee, R.N. 41 Lee, S.Y. 25 Lee, T.C. 21 Lee, Q. 20 Leet, D.M. 104 Lei, K.P.V. 6 Leighly, H.P. 76 Leis, B.N. 16 Lembke, V. 24 Lemkey, F.D. 47 Letizia, I. 63 Letts, M.W. 102 Leverant, G.R. 18 Levi, C.G. 71 Levy, A.V. -98 Lewis, RE. 38 Li, J .C.M. 53 Li, T. 67 Liao, K.C. 42 Liaw, P.K. 86 Licata, T.J. 32 Liddell, K.C. 68 Li-jum, H. 43 Lilius, K. 68 Lillebuen, B. 49 Lin, CoS. 91 Lin,J.C. 8 Lin, M. 59 Lin, M.R. 21 Lin, RY. 46, 76 Lin, T. 82 Lindemer, T.B. 17,72 Ling, E. 9 Linn, J.R. 41 Lippold, J.C. 40, 59 Lipsett, H. 26 Litchfield, J. 55, 81 Litchfield, J .K. 81 Litz, J.E. 51 Litz, L.M. 51 Liu, J.M. 41

Liu, N. 19 Liu, Q.G. 24 Liu, X 89 Liu, Y.X. 50 Livingston, J.D. 42 Lloyd, D.J. 69 Lofsten, A.C. 47 Logas, J.C. 104 London, G.J. 38 Losch, W. 32 Louat, N. 10 Loutfy, R.O. 36 Love, W.L. 61 Lowe, T.C. 59 Lu, M. 91 Lu, WoK. 25 Lu, Y. 60 Lu, Y.Z. 56, 73 Lucas, G. 95 Lucke, K. 58 Luk, S. 15, 71 Lukens, W.E. 33 Lumsden, J.B. 60 Luzzi, D.E. 103 Lyon, O. 17 Lyudkovsky, G. 42

M Maby, E. 91 MacCrone, R.K. 91 MacDonald, B.A. 12, 33 Macfie, D. 61 Mackay, R.A. 73 Mackey, T.S. 50 Macmillan, D.M. Madhukar, M. 41 Mae, Y. 56 Maeda, H. 94, Mahajan, S. 53 Mahajan, Y.R. 52, 56, 75 Mahoney, M.W. 64 Makinen, J. 67 Malone, RA. 7 Malvi, S. 59 Mamantov, C.B. 20 Man, Y. 98 Mandziej, A. 76 Mandziej, S. 76 Mann, M.D. 97 Mannweiler, U. 7 Manson, J.A. 86 Mantena, P.R. 13 Maples, AL. 92 Marabini, A.M. 101 Marcus, H.L. 67 Marcus, P. 45 Marder, AR. 42, 58 Marek, D. 55 Margolin, H. 13, 21 Markworth, A.J. 16,30 Marques, F. 102 Marti, J. 40 Martin, E.S. 8 Martin, J.P. 63 Martin, P. 44 Martinez, L. 11,32,66 Martorell, l.A. 56 Mason, D.R. 35 Masealski, T.B. 30,57,72 Masumoto, T. 13 Masumura, RA. 98 Mateer, M.W. 36 Mathias, M.F. 35 Mstikainen, L. 71 Matocha, C.K. 61 Matsui, S. 94 Matsuo, M. 58 Matyasi, J. 34 Maurer, G.E. 74 May, W.A. 24 Mazgaj, RM. 77 Mehta, J.R. 101 Meier, G.H. 76 Meiners, K.E. 87 Meka, Z.H. 65 Mellerud, T. 49 Merchant, H.D. 92

Merchant, S.M. 54 MeregalJi, L. 102 Merkle, K.L. 6 Meschter, P.J. 38, 40, 75, 88, 97 Meshii, M. 6, 81, 86, 103 Mettham, P.E. 65 Metzbower, E.A. 14, 18 Metzger, M. 60 Meyer, G.A. 50 Meyer, B.A. 100 Meyer, W.T. 100 Michal, G.M. 26, 43 Michel, C. 63 Michel, D.J. 13, 27 Middleton, W.J. 9 Middlin, B. 6 Mikucki, B.A. 90 Mikkelsen, J.C. 38 Miller, D.J. 88 Miller, RE. 78 Miller, S.A 70 Miller, W.A. 93 Mills, M.J. 4 Miner, RV. 80, 88, 89 Minhemius, AJ. Mino, Y. 4 Minoura, J. 9 Minteiro, O.R 29 Mirkovic, O. 35 Mishra, S. 58 Misra, M.A. 3 Mitchell, M.J. 97 Mitchell, T.E. 76 Mitrovic, Z. Mitsune, Y. 9 Mizutani, V. 30 Moen, T. 4 Mohan, N. 91 Mohler, R 55 Moinpour, M. 52 Molnar, S. 94 Monhemius, A.J. 84, 90 Montealegre, R. 90 Montgomery, G.G. 97 Monzen, K. 24 Moore,J. 84 Moore, M. 68 Moore, P.G. 74 Moore, T.J. 26 Morgan, M.J. 82 Mori, H. 103 Morita, Z. 8, 9 Morley, N.W. 65 Morral, F.R. 101 Morris. D.R. 101 Morris, J.G. 21 Morris, J.W., Jr. 6,14,17,92 103 Morrison, C. 98 Moyer, K.H. 100 Mozhi, T.A 97 Mucciardi, F. 41 Mueller, B.A. 71 Mueller, R.R. 17 Muller, E.M. 75 Munroe, N.D.H. 67 Muntz, E.P. 41 Murawa, M.M. 84 Murch, G.E. 79 Murphy, J. 55 Murray, G.T. 81 Murray, J.L. 57 Murthy, A. 71 Murty, K.L. 4, 13, 39 Mutharasan, R 15, 71, 78

Me McCollum, J .M. 95 McCright, R 96 McGill, S.L. 37 McIntyre, D.C. 104 McIntyre, N.S. 45 McKelliget, J. 14,40 McKimpson, M.G. 32 McLean, A 93 McLeod, A.D. 80

112 - TMS-AIME Annual Meeting Program McMahon, C.J., Jr.

39,67,81, 82

McMahon, J.P. 96 McManus, S.P. 79 McMinn, A. 18 McMinn, C.J. 49 McNallan, M.J. 15, 25, 51 McNelley, T.R 64 McQueen, H.J. 4,22,69,86

Osseo-Asare, K. 90 Ostojic, S. 19 0stvold, T. 19 Oudar, J. 45 Owen, C.V. 5 Oye, H.A. 34, 35 Ozcan, K. 65 Ozturk, B. 26, 52

Pro, R. 17 Pronko, P.P. 61 Psioda, J.A. 60 Puchi, E.S. 70 Pullman, W.D. 85 Purdy, G.R 72 Pu-ru, L. 43

p

Qiu, Z. 20 Quesnel, D.J. 14, 28 Quillec, M. 52 Quist, W.E. 87

Q N Nafziger, RH. 9, 23 Nagano, T. 67 Nagelberg, A.S. 76 Nakagawa, A.H. 66 Nakahara, S. 52 Nakamura, T. 11 Nanivadekar, H. 21 Narayan, J. 52 Narayanan, G.H. 87 Nardone, V.C. 5 Nasser-Rati, R 92 Natalie, C.A. 67 Natarajan, K.A. 29 Nathal, M.V. 73 Needham, N.G. 14, 103 Needleman, A. 44 Neelameggham, R 42, 80 Neff, D.V. 63 Nes, E. 70 Nesbitt, J.A. 75 Neumeier, L.A. 58 Newton, C.H. 99 Nguyen, D.C. 81 Nguyen, Q.C. 49 Nguyen, T. 30 Nguyen, T. 76 Nicholas, T. 86 Nieh, T.G. 28 Nikitin, V.Y. 62 Nilmani, M. 10, 24 Ning, Y.T. 102 Nippes, E.F. 55 Nishiike, U. 58 Nishimura, Y. 101 Nitta, C. 30 Nityanand, N. 71 Nix, W.D. 4, 13, 80 Nogi, K. 93 Nolti, F. V. 17 31 Nomura, E. Nordin, M.C. 3 Norr, M.K. 41 Northwood, D.O. 4 Notis, M.R 54 Nourbakhsh, S. 21 Novak, J.W. 77 Nowotny, H. 23 Noyan, LC. 21 Nunez, C. 101 Nunn, RF. 34

o Oderbolz, S. 95 Oedegard, R 62 Oh, D.J. 13, 39 Ohkawa, J. 93 Ohmori, K. 43 Ohr, S.M. 82, 83 Oka, N. 24 Okamoto, H. 57 O'Kane, J. 65 O'Keefe, T.J. 35, 36 Olson, D.L. 3 Olson, F.A. 35 Olson, G.B. 26 O'Malley, M.L. 68 O'Malley, RJ. 52 O'Neal, J.E. 38,40,53,88 Onoda:G.Y., Jr. 18 Opie, W.R 36, 68 Orth, R 68 Ortiz, A. 7 Oseguera, J. 11 Oshima, E. 10

Padilla, R 19 Padial, C.M. 34, 48 Page, RE. 55 Pahlman, J.E. 90 Pak, H. 28 Palmer, C.P. 27 Palmour, H., III 31 Palumbo, E. 41 Pande, C.S. 10, 74, 98 Pangborn, RN. 103 Panigrahy, S.C. 65 Panusch, E. 62 Pao, P.S. 38,97 Papangelakis, V. 51 Parameswaran, K. 11 Parayil, T.R. 22 Parikh, V.N. 61 Paris, H.G. 39 Park, C.G. 82, 83 Park, J.Y. 89 Parker, E.R 98 Parker, RJ. 34 Parkhe, V.D. 56 Paskin, A. 30 Patankar, A. 51 Patel, A.N. 87 Patel, J.R 37 Patterson, B.R 56 Patu, S. 4 Paul, A. 15, 25 Paulson, D.L. 69 Pearson, W.B. 30, 89 Pehlke, RD. 23, 83, 92 Pelton, A.D. 63 Pemsler, J.P. 81 Pendse, RD. 98 Peng, T.C. 38, 53 Perepezko, J.H. 40,71 Perez, N. 13 Perng, T.P. 54 Perra, S. 34, 94 Perruchoud, R. 20 Persson, J. 31 Pesic, B. 37 Peters, E. 90 Petersen, A.E. 42, 51 Peterson, N.L. 78 Peterson, RD. 51 Peterson, RW. 8 Pettit, F.S. 76 Phalman, J.E. 37, 84 Phillips, C.E. 61 Pickering, H.W. 16 Piercy, P. 55 Ping, S.W. 87 Pinski, F.J. 12 Pipes, RB. 41 Pippin, B.H. 20 Pizzo, P.P. 96 Place, T.A. 13 Plantz, P.E. 35 Pocalyko, A. 47 Poirier, D.R 15, 92 Pommier, L.W. 85 Popchenkov, LN. 8 Poveromo, J.H. 30 Prabhu, V.L. 52, 59 Prado, F.G. 84 Prasannan, P.C. 75 Prather, A.V.J. 7 Preban, A.G. 14 Premkumar, M.K. 100 Prewo, K.M. 47 Price, D.W. 31 Price, RF. 85 Priscu, J.C. 80

R Rabin, B.H. 100 Rabinkin, A. 40 Racnas, B.J. 62 Radavich,J.F. 74 Rai, A.K. 61 Rajan, V.B. 82 Rajcevic, H.P. 68, See addenda Ramachandram, V. 69 Ramesh, R 64 Ranade, M. 65 Rangaswamy, M. 33 Ranjan, N. 90 Rao, K.S. 7 Rao,Y.K. 11,25,36,51,52,65 Rapp, RA. 91 Rath, B. B. 10, 12, 18 Rau, M-F. 25 Rauld, J.R 90 Razavi, A. 59 Readey, D.W. 18 Redden, L.D. 59 Reddy, RG. 52, 59 Reed, RW. 41 Rehn, L.E. 79 Reichenecker, W.J. 40 Reid, K.J. 84 Reidinger, F. 40 Reistenberg, E. 55 Rhedey, P.J. 95 Rhode, RW. 59 Rhodes, C.G. 27 Rice, J.A. 43 Richards, G.G. 68 Richards-Frandsen, R 80 Ricou, R 94 Ridder, S.D. 71 Rieck, D. 25 Rigaud, M.R 65 Rigsbee, J.M. 97, 98, 104 Rischeid, E. 55 Ritchie, RO. 82, 83, 98 Ritter, A.M. 74 Roach, G.LD. 48 Roberts, J.T.A. 54 Roberson, M.L. 93 Robertson, D.G.C. 26,46 Robinson, D.J. 35 Roca, A. 101 Rocco, J. 28 Rodbell, K.P. 91 Rodriguez, J. 65 Roenning, S. 62 Rogers, H.C. 59 Rolseth, H.C. 35 Romig, A.D. 16, 73, 79 Romovacek, G.R 20, 35 Rorvik, H. 62 Rosenthal, D.G. 64 Rosenqvist, T. 11 Rossi, F. 96 Rossi, J.D. 10 Rothman, M.F. 88 Routbort, J.L. 98 Roy, A.S. 25 Rungta, R 16 Runkle, J.C. 43 Rupert, M.C. 24 Russ, J. 90 Russell, J.H. 58 Ryum, N. 22, 69, 86

s Sabacky, B.J. 50 Sabatini, RL. 54 Sachan, G.S. 95 Sachdev, A.K. 103 Sadananda, K. 85 Sadoway,D.R. 22,33,80,81 Safarova, L.E. 8 Safran, S.A. 5 Sahai, Y. 15, 96 Saint-Romain, J.L. 21 Saito, M. 10 Sakai, K. 24 Sakai, T. 58 Sakoh, Y. 65 Sakono-oka, A. 56 Saksvikrjlnning, T. 4 Salerno, J.S. 27 Salome, P. 99 Salvati, L. 60 Sanchez, J.M. 16,32 Sanders, T.H. Jr. 87 Santiago, F., 41 Sarkar, G. 73 Sass, S.L. 72 Sastry, S.M.L. 12, 38, 53 Satoh, K. 9 Sautebin, R. 78 Savage, H.S. 104 Savage, S.J. 75 Scarr, G.K. 18 Scattergood, RO. 31, 98 Schaefer, RJ. 10, 54, 74 Schmid, R 8, 42, 89 Schmidt, P.A. 90 Schmidt-Hatting, W. 48 Schneibel, J.H. 32, 66 Schoen, J.W. 58 Schoener, R 19 Schooler, L.N. 34 Schramm, S.W. 41 Schrott, A.G. 77 Schulson, E.M. 53 Schultz, A.H. 42 Schiirmann, E. 8 Schuster, J.C. 23 Schwarzkopf, E.A. 79 Schweizer, F.A. 74 Schwer, RE. 74 Scott, P.A. 104 Scutti, J.J. 96 Seagle, S.R 18 Seidel, D.C. 59 Seigle, L.L. 78 Sellers, C.M. 70 Semiatin, L. 59 Setzer, W.C. 87 Shahapurkar, D.S. 8, 23 Shahinian, P. 85 Sharma, R.A. 36 Shatynski, S.R * 76, 91 Shea, M.M. 103 Shekhar, S. 21 Shen, T.H. 58 Shen, Z.S. 10 Shenoy, RN. 88 Sheppard, T.J. 70, 86, 87 Sherwood, W.J. 76 Shiao, B. 59 Shibata, Y. 9 Shimizu, T. 24 Shimizu, Y. 58 Shin, K.S. 86 Shin, S.M. 104 Shingler, M.J. 88 Shirley, D.R 4 Shirts, M.B. 42 Shmorgunenko, N.S. 77 Siegel, M.W. 90 Siemens, RE. 58 Sieradzki, K. 30 Sigli, C. 16 Siklosi, P. 34 Simkovich, G. 45, 51, 88, 92 See addenda! Thermo I Singer, RF. 38 Singh, N.B. 74 Singh, R.P. 22

TMS-AIME Annual Meeting Program - 113 Singhal, S.C. 91 Sinha, N.H. 19 Sismanis, P.G. 31 Sisson, R.D. Jr. 75, 91 Sittard, M. 8 Siraev, N.S. 77 Sivakumar, T.J. 48 Sivila, L. 85 Skidmore, D. 55 Slane, J .A. 43 Sleppy, W.C. 77 Small, M. 8, 23 Smeggil, J.G. 75 Smialek, J.L. 76 Smith, D.A. 10 Smith, D.W. 45, 100 Smith, H.H. 13 Smith, 1.0. 4 Smith, J.F. 9, 23 Smith, R.L. 69 Smith, S. 74 Smola, V.S. 8 Smugeresky, J.E. 100 Snow, D.B. 3 Snyder, L.C. 37 Sobolev, I. 62 Sohn, H.Y. 19,51,67,72 Solberg, J.K. 22, 86 Solbu, A. 4 Soleiman, M.K. 25 Solomon, A.D. 25 Solorzano, I.G. 72 Soman, S.N. 51 Sommerville, I.D. 26, 52, 93 Sorlie, M. 35 Sosinsky, D.J. 93 Soullard, J. 11 Southwick, P.D. 42 "Seapen, F. 54 Spector, S. 37 Spring, K.A. 50 Spoel, H. 96 Srivastava, S.K. 64 Srolovitz, D.J. 5 Stahlin, W. 94 Starke, E.A. Jr. 38, 87 Stavropoulos, G. 11 Steele, D.K. 42 Steele, J .H. 67 Stefanescu, D.M. 92 Stefani, J. 5 Stephens, J.J. 80 Stephens, J.R. 46 Stephenson, E.T. 43 Sterten, A. 62 Steward, T.L. 6 Stocks, G.M. 12 Stoehr, R.A. 15, 91 Stok, A. 19 Stokka, P. 49 Stoloff, N.S. 53, 75, 80 Stone, S.E. 81 Stott, C.M. 85 Stout, M.G. 44 Strege, K.E. 52 Subbaiah, T. 7 Subramanian, E.V. 64 Subramanian, K.N. 21 Suga, Y. 58 Suh,J. 18 Sun, J-X. 39 Sunlop, G.L. Suresh, S. 13, 45, 66 Sussman, R.C. 93 Swartzendruber, L.J. 57 Swearengen, J.C. 59 Szecket, A. 28, 101 Szekely, J. 14, 15, 40, 71, 84 Szesny, B. 36

T Tabereaux, A.T. 4, 94 Taberlet, E. 15 Tagliaferri, V. 5 Talcott, R.M. 34 Tallert, H.E. 65 Tanaka,T. 9

Tanner, L.E. 71 Tasaka, S. 48 Taub, A.l. 27,80 Taylor, M.P. 62, 95 Taylor, P.R. 51 Taylor, S.D. 7 Telesman, J. 27 Telyatnikov, G.V. 77 Teramura, H. 101 The, P.J. 34,48 Themelis, N.J. 65,67 Thibault, M.A. 95 Thiemer, J. 91 Thistiethwaite, S.R. 63 Thomas, G. 14,64, 73, 98 Thomas, M.T. 45 Thomas, S. 45 Thompson, A.W. 81,99 Thompson, D.G. 40 Thompson, S.W. 72 Thomson, R.M. 29, 83 Thonstad, J. 62 Thorpe, S.J. 12 Tien, J.K. 5,73,74,79,80 Titze, H.O. 78 Tiwari, B.L. 36, 50 Todd, J. 77 Toguri, J.M. 11,93 Topor, L. 42 Torklep, K.E. 35 Torma, A.E 29 Tosten, M.H. 13, 73 Traulsen, H.R. 24 Tressler, R.E. 32 Tricklebank, S.B. 62 Trybus, C.L. 100 Tsai, C.V. 28 Tsay, Y.L. 55 Tsumeizumi, T. 93 Tsuyuguchi, S. 24 Turkanis, J.L. 86 Turner, D.L. 27 Tumey, J.R. 37 Twist, J.R. 61

u Ujiie, S. 20 Ulrich, K.T. 33 Underwood, E.E. 82 Unnam,J. 88 Upadhya, K. 26, 52 Urata, N. 48 Utigard, T. 93

v Vaaler, L. 55 Valdo, A. 96 VanAken, D.C. 39 Vandell, T.D. 7 VanDenAvyle, J.A. 27 Vander Sande, J.B. 26,38,87 Van Riper, G.G. 7 Vasudevan, A.K. 13,66, 73 Vaught, C. 95 Vecchio, R.S. 83,99 Vedernikov, G.F. 20 Vedula, K.M. 88 Venables, J.D. 60 Venkatachalam, S. 51, 59 Venugopalan, P. 62 Vigueras, D.J. 28 Visknev, V.G. 20 Vittadini, I. 102 Vives, Ch. 94 Vizsolyi, A. 29 Vogt, M.F. 34 Void, C.L. 103 VOlker, R. 8 Voorhees, P.W. 10, 74, 79 Vos, R.J. 29

w Wada, H. 46 Wadsworth, J. 86

Wadsworth, M.E. 36, 51, 68 Waeber, W.M. 78 Wagner, G.P. 88 Wagoner, R.H. 10, 21 Wagstaff, F.E. 95 Wahnsiedler, W.E. 48 Walker, L.K. 34 Wall, M. 72 Walline, R.E. 7 Wallner, J. 10 Walqui, H. 65 Walton, R.P. 20 Wang, J.S. 13 Wang, L. 92 Wang, Z.R. 13, 21 Warner, S.J. 67 Warnes, D.E. 100 Warren, G.W. 30, 31, 68, 90 Warren, R. 98 Wasynczuk, J.A. 73 Watson, D. 88 Watson, R.E. 11 Watters, J.F. 79 Wayman, C.M. 72 Weaver, C. 63 Webb, R. 33 Weeks, J.R. 39,54 Weerasooriya, T. 86 Weertman, J.R. 73 Wei, R.P. 16,97 Weirick, N.E. 47 Weiss, I. 53 Wells, M.E. 18 Welch, B.J. 62, 94 Welsch, G.E. 76 Wenching, S. 68 Weng, T.-L. 62 Wert, J.A. 27,86 Wert, J.J. 97 Wesely, R. 65 West, R.N. 76 Westengen, H. 87 Westmacott, K.H. 72, 78 Whang, S.H. 53, 56, 73, 102 White, C.L. 32, 66 White, R.G. 77 Whitsnant, J.S. 42 Wichlacz, P.L. 55 Wiedemann, K.E. 88 Wiegers, B.W. 84 Wiertz, J. 29 Wiggins, C.J. 97 Wilde, B.E. 10, 97 Williams, F.S. 34 Williams, J.C. 3, 12, 18, 45, 53, 102 Williams, R.L. 100 Williams, R.O. 89 Willis, G.M. 11 Wilson, B.L. 87 Winand, R. 3.6 Winborne, D.A. 6 Winkhaus, G. 77 Witt, R.H. 47 Woerz, H. 10 Wojcik, C.C. 43,44 Woo,J. 71 Wood, A.H. 19 Wooten, J.R. 44 Worrell, W.L. 24, 83 Worzala, F.J. 27,83 Wriedt, H.A. 23 Wright, P.K. 46, 73, 79 Wright, R.N. 64, 69 Wu,J.-K. 82 Wu,L.H. 50 Wu, T.W. 54 Wynblatt, P. 32

y Yabe, T. 24 Yablonsky, K.V. 8 Yamada, K. 48 Yan, J. 98 Yang, C.H. 76 Yang, C.J. 21 Yang, C.Y. 5

Yao, P.C. 46, See addenda! Thermo I Yap, B.K. 8 Yates, M. 55 Yazici, R. 21 Yen, S.-C. 50 Yip, S. 30 Yokokawa, H. 20 Yoon, D.N. 100 Yoon, S.-Y. 81 Yoshihara, M. 48 Yost, F.G. 73 Youdelis, W.V. 17 Young, C.S. 47 Young,S. 24,36 Yu, H. 96 Yuan, B.L. 50 Yue, A.S. 5 Yu-Qing, W. 67

z Zabreznik, R.D. 4, 19, 48, 62, 94 Zaiken, E. 83 Zakharova, G. 8 Zambo, J. 48 Zee, R.H. 79 Zeik, K. 10 Zhang, M. 20 Ziegenbalg, S. 34 Zindel, J.W. 39 Zwicker, J.D. 94