Effect of fiber length on the wear resistance of short carbon fiber reinforced epoxy composites

In this study, the influence of fiber length on tribological properties of short carbon fiber (SCF) reinforced epoxy composites was investigated. Both a block-on-ring and a pin-on-disk apparatus were applied for the study of sliding performance of composite specimens against polished steel counterparts under dry conditions. It was found that composites with longer SCF (nominal length = 400 μm) exhibited better wear resistance than those with shorter SCF (nominal length = 90 μm), in both cases either with or without graphite flakes and TiO2 nanoparticles. This effect seemed to be more pronounced at higher contact pressures applied. Furthermore, the steady frictional coefficient and contact temperature were reduced slightly by longer fibers. The relationships among the frictional coefficient, the contact temperature and the wear rate were discussed under the support of scanning electron microscope observations of the worn surfaces.