Heterogeneous structures with inhomogeneous inclusions under elastohydrodynamic lubrication contact with consideration of surface roughness

Abstract

In order to predict the microscopic response of surface coatings and subsurface inhomogeneous inclusions, a semi-analytical solution is developed for heterogeneous materials subjected to elastohydrodynamic lubrication contact. In this solution, the inhomogeneous inclusions are homogenized according to Eshelby’s equivalent inclusion method with unknown eigenstrains to be determined. The topmost coating is assumed as an inhomogeneous inclusion of finite size and thus simulated with the same methodology. The disturbed surface deformation due to the presence of coatings and inhomogeneous inclusions are iteratively introduced into the lubricant film thickness until a convergence is achieved. The effects of surface roughness on the pressure and film thickness profiles and subsurface elastic fields are considered to approach the engineering practice. This solution takes into account the interactions between the loading body, the fluid lubricant and the coating/substrate system with embedded inclusions.