Influence of aramid fabric on fretting wear performance of polyetherimide composite - Polyimides and Other High Temperature Polymers - page 509

Influence of aramid fabric on fretting wear performance
of polyetherimide composite

∗ ,1 2

J. INDUMATHI,

1 Industrial Tribology, Machine Dynamics and Maintenance Engineering Centre (ITMMEC), Delhi,
Hauz Khas, New Delhi 110016, India
2 Centre for Polymer Science and Engineering (CPSE), Indian Institute of Technology, Delhi,
Hauz Khas, New Delhi 110016, India

JAYASHREE BIJWE and ANUP K. GHOSH

Abstract—Polyetherimide (PEI) is a high temperature engineering thermoplastic polymer (Tg
218 ° C and m. p. 380 ° C) with very good combination of mechanical and electrical properties along
with easy injection mouldability. Its fibre reinforced and solid lubricated composites have shown
excellent tribological potential in adhesive wear mode. In fretting wear mode, however, only very
little is reported in the literature on short fibre reinforced and solid lubricated composites of PEI and
not at all on fabric reinforced composites. The authors have reported in their earlier papers on the
significant potential of carbon fabric for improving the fretting wear performance of PEI. In this pa-
per efforts have been devoted to explore the tribo-potential of aramid (Kevlar 29) fabric for improv-
ing fretting wear performance of PEI. It was observed that aramid fabric (lighter and less expensive
than the carbon fabric) improved the fretting wear behavior of PEI significantly. The friction coeffi-
cient of PEI (0.4) was independent of operating conditions while that of aramid fabric composite
(AFC) very much depended on both load and temperature. Overall, fabric inclusion reduced the fric-
tion coefficient of PEI from 0.4 to 0.3 and the specific wear rate to one-third which is very signifi-
cant improvement. The tribo-performance improvement capability of aramid fabric (AF), however,
slightly deteriorated at high operating temperature (150-200 ° C). The study of worn surfaces by
SEM proved to be very helpful in understanding wear mechanisms. It was observed that higher
temperature (200 C) was more damaging to the fabric, and hence to the performance of the compos-

ite, rather than the higher load (200 N).

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Keywords : Polyetherimide; fretting wear; high temperature polymer; aramid fabric reinforced
composite.

1. INTRODUCTION

Fretting wear is a type of wear which occurs when there is a small amplitude os-
cillatory movement between contacting surfaces. This phenomenon generally
takes place in the case of bearings; gears; bushes; multilayer leaf springs; pallia-
tives; bolted, riveted and pinned joints; bearing liners; spline couplings; gripped