Tribological Properties and Microstructure Evolution of Cu-Graphite-Ti3AlC2 Composites Fabricated by SPS

Abstract:

Ti₃AlC₂ was added into Cu-graphite composites to enhance their tribological properties. The impact of sintering temperature on properties of Cu-graphite-Ti₃AlC₂ composites (CGTCs) fabricated by spark plasma sintering (SPS) was studied, including microstructure, density, hardness, electrical conductivity, interfacial properties, and tribological behavior. The results indicate that mutual diffusion between Ti₃AlC₂ and Cu occurs during sintering, leading to metallurgical bonding. Moreover, titanium atoms originating from Ti₃AlC₂ undergo a reaction with carbon atoms on the graphite surface, facilitating enhanced bonding between Cu and graphite. CGTCs exhibit promising lubrication performance at different sintering temperatures, with friction coefficients ranging from 0.15 to 0.25. The wear rate decreases and then increases with the increase of sintering temperature. Optimal tribological properties are achieved at 980 °C, when the average friction coefficient and wear rate are 0.18 and 4.82×10^-6 mm³·(N·m)^-1, respectively.