WEAR
RESISTANCE
COMPOSITES
OF
FILLED
EPOXYPOLYAMIDE
IN AGGRESSIVE
MEDIA
V. S. G u m e n y u k , G . A. a n d S. D. L e k h m a n
Kulinskii,
UDC 539.4 : 539.62
The authors investigate the influence of c e r t a i n a g g r e s s i v e m e d i a (toxic c h e m i c a l s ) on the w e a r r e s i s t a n c e of filled epoxypolyamide c o m p o s i t e s . The p r e s e n c e of toxic c h e m i c a l s in the zone of friction c a u s e s a s h a r p fall in the w e a r of the p o l y m e r s . The m a x i m u m w e a r r e s i s t a n c e is displayed b y epoxypolyamide c o m p o s i t e s filled with iron powder, c e m e n t , o r graphite.
Metal s u r f a c e s o p e r a t i n g in d i r e c t contact with toxic c h e m i c a l s (in p a r t i c u l a r , the working s u r f a c e s of sliding b e a r i n g s ) in c r o p - s p r a y i n g machines often b e c o m e c o r r o d e d and u n s e r v i c e a b l e . In a p r e v i o u s p a p e r [1] we showed that g l a s s - f i b e r - r e i n f o r c e d m a t e r i a l s a r e p r o m i s i n g for o p e r a t i o n in a g g r e s s i v e media. One w a y of i n c r e a s i n g the s e r v i c e l i v e s of m e t a l components o p e r a t i n g in a g g r e s s i v e m e d i a is to deposit on t h e i r s u r f a c e s thin epoxypolyamide c o a t i n g s , which have good adhesion to m e t a l s and good m e c h anical strength. A n t i c o r r o s i o n epoxypolyamide coatings a r e deposited on clean d e g r e a s e d m e t a l s u r f a c e s of f r a m e components in the f o r m of solutions in acetone; on the internal s u r f a c e s of the m e t a l m a t r i c e s of sliding b e a r i n g s , t h i n - l a y e r epoxypolyamide coatings (up to 0.5 ram thick} a r e deposited b y sizing [2]. In this a r t i c l e w e d i s c u s s the w e a r r e s i s t a n c e of epoxypotyamide c o m p o s i t e s with v a r i o u s d i s p e r s e d fillers. The epoxide c o m p o s i t e s w e r e p r e p a r e d as follows. Epoxide r e s i n E D - 6 was heated to 70-80°C, weighed on a m i c r o b a l a n c e in a clean g l a s s v e s s e l , and mixed with the f i l l e r s which w e r e d r i e d for 3 h at 150°C; L - 1 9 a m i n o p o l y a m i d e (30 p a r t s by weight to 100 p a r t s o f r e s i n ) was added to the m i x t u r e which was cooled to 25-30°C, and then the c o m p o s i t e was c a r e f u l l y s t i r r e d . The filler contents of the c o m p o s i t e s h r e listed in Table 1. Our method of investigation was the s a m e as that d e s c r i b e d in [1]. The r e s u l t s a r e plotted in Fig. 1. The l e a s t d e g r e e of w e a r is that for c o m p o s i t e 7, filled with iron powder, c e m e n t , and graphite; the g r e a t e s t is that of c o m p o s i t e s 1, 9, 1i, and 12. It is c h a r a c t e r i s t i c that c o m p o s i t e 5, filled with the sam.e amount of d i s p e r s e iron and c e m e n t as c o m p o s i t e 7 but without the g r a p h i t e , w e a r s five or six t i m e s f a s t e r than c o m p o s i t e 7. This shows that g r a p h i t e has a m a r k e d effect on the a n t i f r i c t i o n c h a r a c t e r i s t i c s of the c o m positions. C o m p o s i t e 10, titled with graphite only, differs little f r o m c o m p o s i t e 7 in w e a r . C o m p o s i t e 3, filled with 200 p a r t s b y weight of iron, also has high w e a r r e s i s t a n c e . In a g g r e s s i v e media, which act like a kind of l u b r i c a n t , the w e a r of our c o m p o s i t e s was much r e duced. On c o m p a r i n g the w e a r of c o m p o s i t e 7 with the p r e v i o u s l y e x a m i n e d m a t e r i a l s [1], we can conclude that c o m p o s i t e 7 (with d r y friction o r in v a r i o u s media) w e a r s 2-3 t i m e s s l o w e r than s t e e l 3, 8-10 t i m e s s l o w e r than c a s t iron or unfilled epoxypolyamide c o m p o s i t e s , and twice as f a s t as g l a s s - f i b e r - r e i n f o r c e d p l a s t i c with f i b e r s lying p e r p e n d i c u l a r to the plane of friction. Ukrainian A g r i c u l t u r a l A c a d e m y , Kiev. T r a n s l a t e d f r o m Mekhanika P o l i m e r o v , No. 3, pp. 535-537, May-June, 1974. Original a r t i c l e s u b m i t t e d June 20, 1973.
© 1975 Plenum Publishing Corporation, 227 West 17th Street, New York, N.Y. 10011. No part o f this publication may be reproduced, ] stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, 1 recording or otherwise, without written permission o f the publisher. A copy o f this article is available from the publisher for $15.
453
T A B L E I. F i l l e r C o n t e n t s o f E p o x y p o l y a m i d e C o m p o s i t e s (per 100 p a r t s b y w e i g h t o f e p o x i d e r e s i n a n d 30 p a r t s b y w e i g h t of a m i n o polyamide) ,,,, . . . . .
Composire No.
Parts by weight
Filler
Ironpowder Same
50 200 120 5 120
Cement Grade 400 Tale
I m~'l~m -z
i
a
7
-t
Parts by weight
Filler
8
10 2O 120
9
Asbestos Aluminum
60 120
20 25
10
Graphite
60 50
I1 12
Asbestos ,,
4O 15 10 2O
powder
t2 : m~n3.km -1,
/ 7 /J . / ~
.... ~
b
2
t2
~/,,
t2
!
.
120
/7
t2
8
,,
~Iron powder t Cement Grade 400 Graphite Iron powder
160
Talc " " Iron powder Cement Grade 400 Iron powder
t$
Compos- ] ite No. ]
0,8
o., 0,5 ~
-
..... 0,¢o
~ 7 *
5
6
7
5
pkg.cm -z I ~
C~3
"
7
f--
2 :Im rr~.km-Z
m~3.~m-1 I
d
,2
pkg.cm-2 2/f2
~ g.,
to
O,2
o,t
1
e
3,10
•
$
6
7
Pkg'crn-2
4
5
6
7
pkg'cm-2
F i g . 1. W e a r of f i l l e d e p o x y p o l y a m i d e e o m p o s i t s vs r e l a t i v e l o a d . a) D r y f r i c t i o n ; b) in w a t e r ; c) in N u v a r c r o n - 2 0 ; d) in a m m o n i a . F i g u r e s on c u r v e d e n o t e n u m b e r s o f c o m p o s i t e s . S l i d i n g s p e e d , 0.5 m / s e c . G l a s s - f i b e r - r e i n f o r c e d p l a s t i c a n d c o m p o s i t e 7 w e r e t e s t e d b y us a s s l i d i n g b e a r i n g s and p r o t e c t i v e c o a t i n g s f o r p u m p s w o r k i n g in a g g r e s s i v e m e d i a ; t h e y a r e r e c o m m e n d e d f o r u s e in t h e p r o d u c t i o n to v a r i o u s c o m p o n e n t s and units in c r o p - s p r a y i n g m a c h i n e s .
LITERATURE 1,
2.
454
CITED
V. S. Gumenyuk, G. A. Kulinskii, and S. D. Lekhman, Mekhan. Polimerov, No. 2,364 (1974). G. A. Kulinskii, Teklmologiya i Organizatsiya Proizvodstva, No. I, 87 (1972).
