Investigating the Effect of Surface Finish on Mixed EHL in Rolling and Rolling-Sliding Contacts

Surface finish may significantly affect the lubrication performance of a tribological interface through the influence of topography on micro/nanoscale fluid flows around localized contacts at surface asperities. This paper aims to study the mixed lubrication performance of a group of engineered surfaces, including turned, isotropically finished, ground, and dimpled surfaces, under different operation conditions by means of a deterministic mixed elastohydrodynamic lubrication (EHL) model. The honed surface was used to mate with other surfaces. The results indicate that a longitudinal contact ellipse favors longitudinally oriented mating surface roughness and that a transverse contact ellipse, as well as a line contact, prefers a transversely orientated mating surface roughness for lubrication enhancement.