Tribological investigation of boron carbide films sliding against different mating materials under high relative humidity

Abstract

Tribological performances are significantly affected by the tribo-chemical reaction of the mating materials, while the effect on the B4C film under high relative humidity conditions are poorly investigated. Therefore, fiction tests of three tribo-pairs (B4C/WC, B4C/steel and B4C/Al2O3) under 85 % RH with various normal loads and sliding frequencies were performed. The results show that the B4C/WC tribo-pair exhibits excellent tribological properties, including very stable friction curves, minimum friction coefficients & wear rates, maximum carrying-load capacity and the smallest fluctuations with the change of the normal load. Similar results have been obtained for the B4C/WC tribo-pair with the increase in the sliding frequency. This is mainly attributed to the oxidation of WC to form WO3 that is conducive in enhancing the tribological performances. Therefore, the sliding contact of B4C/WC is the desirable design for engineering applications under high relative humidity.