Effect of graphitization on microstructure and tribological properties of C/SiC composites prepared by reactive melt infiltration

Carbon fiber reinforced SiC matrix (C/SiC) composites for use in future advanced braking systems were prepared by reactive melt infiltration with and without graphitization before siliconizing. The effect of graphitization on tribological properties of C/SiC composites was studied by simulating the normal landing of aircraft. The results showed that a dense microstructure and high thermal diffusivity were obtained by the graphitization. After braking tests, high and stable coefficient of friction could be obtained, due to the formation of uniform and continuous debris film on the rubbing surface of the graphitized samples. Simultaneously, the wear rate was slightly higher because of the high coefficient of friction, but still lower than the results in other researches.