The effect of pre-treatment of substrate on fretting tribological behavior of MoS 2 coatings

Abstract

MoS 2 coatings were deposited by a radio frequency (rf) sputtering process on 1045 steel substrate which was pre-treated with ion-plated TiN and shot-peening processes. A series of fretting wear experiments were conducted to investigate the effects of various properties of substrate induced by different pre-treatment methods on the fretting tribological behavior of MoS 2 coatings. The results showed that the fretting damage of MoS 2 coating was greatly dependent on the surface characteristics, mechanical and physical-chemical properties of the substrate. The transfer and smearing of MoS 2 coating in the initial wear stage, the oxidation, and delamination of MoS 2 layers in the later wear process, were always subjected to the effects of mechanical properties of substrate, surface morphology, distribution of contact stress, and the adhesion strength of MoS 2 coatings. Additionally, the fretting tribological behavior of MoS 2 coatings was also affected by the change of its microstructure, the plastic deformation ability of the substrate and their synergistic effect.