Influence of weave of glass fabric on the oscillating wear performance of polyetherimide (PEI) composites

Glass fabric of three weaves (plain, twill and woven) was selected as reinforcement for developing composites based on polyetherimide matrix. One more composite containing additional fillers (PTFE and Cu powder) was also formulated to investigate the influence of fillers on the wear performance. The composites were characterised for compositional, thermal and mechanical properties. Oscillating (small amplitude) wear studies were done on these composites on SRV Optimol Tester (ball on plate configuration) under different loads for all the composites and temperatures in the case of one. It was observed that plain weave proved to be the most effective in enhancing the wear behaviour of PEI by three times. Friction coefficient also was comparatively low in this case (≅50% reduction at higher loads as compared to neat PEI and other composites). Inspection of worn surface revealed that very thin and uniformly spread layer of back-transferred polymeric material, adhering very strongly to the fabric was observed to be the reason behind this. Twill weave and fillers, however, performed poorly resulting significant deterioration in wear performance while woven fabric showed some improvement in wear performance at higher loads. Moreover, mechanical properties of the composites did not support the trends in the wear behaviour. Thus nature of weave proved to be the most prominent wear controlling factor. SEM studies were done on the worn surfaces to understand reasons for failure of some composites and influence of operating parameters.