Effect of fiber orientation on tribological properties of fiber-reinforced C/C-SiC composites mated with ceramic ball

Carbon fiber-reinforced SiC ceramic matrix composites (C/C-SiC composites) with advantages of high wear resistance and corrosion resistance are of high application potential as ceramic bearings. In this study, the frictional and wear behaviors of C/C-SiC with different fiber orientations mating with Al2O3 and SiC balls, respectively, have been investigated. Results reveal that fiber orientation effectively affects the friction and wear properties of carbon-ceramic composites in paired friction experiments with ceramic balls. In comparison to C/C-SiC with unidirectional fiber orientation, C/C-SiC pads with randomly arranged fibers exhibited a more stable coefficient of friction and lower volume wear, presenting the best performance among the pads considered herein, which may have the potential to be applied to bearing materials. The factors affecting the formation of continuous tribo-film, which influence the comprehensive performance, are researched. It is proposed that the amount of wear debris and the formation of SiC/SiC micro-hard frictional pairs may inhibit or promote the formation of continuous friction film. The dominant wear mechanisms for friction pairs of C/C-SiC and ceramic are abrasive wear and oxidation wear.