Influence of weave of carbon fabric on low amplitude oscillating wear performance of Polyetherimide composites

Three composites were fabricated based on Polyetherimide (PEI) matrix and carbon fabric (CF) (55 vol.%) of different weaves, viz. plain, twill and satin (4H) by impregnation technique. These composites were evaluated for various mechanical properties and tribological performance in low amplitude oscillating wear (LAOW)/fretting wear mode. It was observed that CF reinforcement led to a significant enhancement in all strength and modulus properties of PEI except elongation to break (e). Twill weave proved to be the most effective followed by satin and plain weave in almost all the properties. The LAOW mode evaluation under various loads revealed that the wear performance order was exactly opposite to the above trend. Overall, plain weave composite was the best performer followed by twill and satin. Various wear mechanisms, such as fiber-matrix debonding due to repetitive reciprocating shearing stresses, micro-cracking, micro-cutting and pulverization of fibers followed by removal of debris from the contact zone were operative during such wear situation. Amongst these processes, generation of fiber debris, their temporary retention in fabric weaves and subsequent removal from the crater played a key role in overall wear performance. The ability of plain weave to hold back the debris was maximum that resulted in lowest wear while satin weave had the minimum retention ability that led to the highest wear. The proposed wear mechanisms were supported by SEM studies.