Role of fabric reinforcement on the low amplitude oscillating wear of polyetherimide composites

Influence of fabric reinforcement in polymers is well investigated in the unidirectional sliding wear mode leading to adhesive wear of the composites, but not in the case of low amplitude oscillating (fretting or reciprocating) wear mode. In the authors' laboratory, series of polyetherimide (PEI) composites reinforced with fabrics of carbon and glass were investigated in this respect. In this paper, results on the low amplitude oscillating wear of three composites, viz. C-CF, C-AF and C-HY containing fabrics of carbon (CF), aramid (AF) and combination of both (hybrid, HY) based on PEI matrix are presented. After characterizing for physical and mechanical properties, these composites along with the unfilled PEI (C-0) were evaluated for their low amplitude oscillating wear performance on SRV optimol tester under different loads and temperatures using ball-on-pin configuration. It was concluded that the carbon fabric proved to be significantly beneficial in improving the friction and wear performance of PEI under all loads and temperatures. AF inclusion on the other hand, proved beneficial for improving the friction behaviour moderately. It also improved the wear performance of PEI under high loading conditions but not under high temperature conditions. At 100 degreesC, the wear performance was poorer than that of unfilled PEI. Interestingly, friction behaviour of hybrid composite was almost similar to that of CAF but not the wear behaviour. The wear performance of C-HY under high loading condition was little lower than that of CAF, but significantly better than that of unfilled PEI. The C-HY had clear edge over C-AF in the high temperature wear performance. At temperatures up to 150 degreesC, it exhibited improved wear performance unlike C-AF. Beyond that, however, the performance deteriorated. SEM studies proved to be helpful in understanding the wear mechanism. (C) 2003 Elsevier B.V. All rights reserved.