Wear behaviour of molybdenum disulphide diffusion coatings under vacuum conditions

Abstract

Strong adhesion is a particular trait of an effective thin film solid lubricant. A new technological process for the synthesis of MoS 2 diffusion coatings has been developed to improve the adhesion. It allows formation of the solid lubricant layer with uniform thickness even for details having complex geometrical shapes. The coating consists of the MoS 2 as a base layer and the transition zone alloyed with sulphides of substrate elements (Fe, Ni, Cr, etc.). The total thickness of the diffusion coating can be varied between 10–100 μm. The wear intensity of the MoS 2 diffusion coatings is sufficiently low in comparison with that of the traditional MoS 2 coatings. The main wear mechanism of the MoS 2 diffusion coatings is fatigue wear caused by crack generation. The technology developed is promising for improvement of serviceability, reliability and durability of mechanical units (bearings, gears, seals, etc.) working under vacuum conditions, under high loads and over a wide temperature range.