Some tribological properties of SHS-produced chromium sulfide

Oxidation resistance and tribological properties of SHS-produced chromium sulfide have been explored. The material was oxidized up to 5 to 7 μm thick from its surface upon heat treatment at 1000°C for a short time. It also exhibited a unique compositional change in sulfur and chromium at the interface between matrix and oxide layer formed during heat treatment. Meanwhile, the synthesized material showed the coefficient of kinetic friction of below 0.18, which is an acceptable value for a solid lubricant. Although the friction coefficient of CrS was initially low, it was found to grow upon high-temperature oxidation of the CrS surface. This fluctuation in the tribological property seems to depend on both the crystal structures of chromium sulfide and chromium oxide and of the interface between the oxide and matrix.