Environmental Effects on the Composition of Surface Films Produced by an Organo-Molybdenum Compound©

Abstract

The influence, of environments on the properties of the surface films formed, with molybdenum dithiocarbamate (MoDTC) was examined under a reciprocating sliding condition. MoS₂ was formed on the rubbing surfaces in air and oxygen, and molybdenum compounds with an oxidation state lower than MoS₂ were produced in nitrogen and argon. The surface film composed of MoS₂ was effective in reducing the friction and wear, while the molybdenum compound formed in nitrogen or argon had no ability to prevent direct contact between the rubbing surfaces and to reduce the friction. It was a necessary condition for forming the surface film composed of MoS₂ that the environment to be rubbed contained oxygen at a concentration above a certain level.