A kinetic study of interface reactions for an organic molybdenum compound as a lubricant additive

Abstract

The kinetics of molybdenum-sulphur compounds as anti-wear and extreme pressure additives are studied on a V-block-pin testing machine. The surface films of pins are analysed by Auger electron spectroscopy (AES). The apparent reaction order in the general kinetic equation can be determined from the experimental data. The results show that the composition of the surface film depends on the relative reaction rates of sulphidation and oxidation and k S k O can be found from the AES profile, where k is the reaction rate constant. The surface film of a mixture of iron oxide and sulphide possesses better anti-wear properties than the sulphide film alone.