The influence of surface roughness and viscosity on micropitting damage

Abstract

Purpose This study aims to investigate the influence of surface roughness and viscosity on micropitting and their influence sequence. Design/methodology/approach Specimens were made of carburized and quenched 18CrNiMo7-6, and different surface roughness was obtained by grinding and shot peening. Tests were carried out on a rolling-sliding tribometer, with different viscosity lubricants and a heavy load under a boundary lubrication condition. The laser confocal microscope was used to measure the aspects, surface roughness, profiles in the contacted region and micropitting damage percentage. A factorial experiment was designed, and the range analysis was applied to find the sequence of influence of surface roughness and viscosity. Findings The result shows that surface roughness has a more noticeable influence since the change of viscosity cannot generate sufficient wear loss to suppress micropitting. Originality/value The influence sequence of two factors on micropitting was investigated and the reason for the distribution was analyzed.