Influence of weave of carbon fabric in polyetherimide composites in various wear situations

Bi-directionally (BD) reinforced composites enjoy the combination of benefits of best possible enhancement in mechanical properties in two directions, enhanced tribo-performance, ease in processing, etc. Polyetherimide (PEI) is a promising specialty thermoplastic polymer with very good mechanical and thermal properties. In composite form, it has exhibited significant tribo-potential. Carbon fabric (CF) reinforcement is most favored from mechanical strength and tribological point of view, especially in dry adhesive wear mode. Though weave of fabric is known to control properties of composites, collective information is not available in the literature on the role of weave in controlling tribo-performance of composites in various wear modes. Hence, three composites of PEI containing 55 vol.% CF with three weaves, viz. plain (P), twill (T) and satin 4-H (S) were fabricated by prepreg (impregnation) technique followed by compression molding. These were characterized for physical and mechanical properties. In depth studies in four dry wear modes, viz. adhesive, fretting, abrasive and erosive were conducted on these composites. The twill weave proved to be the best for enhancing most of the mechanical properties of the composites followed by satin and plain. In case of tribo-performance, however, the role of weave varied with wear modes. No weave performed best or poorest in all wear modes. Different wear mechanisms were proposed to analyze the role of weave of fabric.