Effects of 3D anisotropic heterogeneous subsurface topology on film thickness, pressure, and subsurface stresses in an elasto-hydrodynamically lubricated point contact

Bearing steel on a sufficiently small scale is strongly heterogeneous and anisotropic. To enable evaluation of the criticality of particular aspects of the microstructure, in this paper an EHL model is solved by the developed multigrid algorithm for a full 3D elastic domain containing varying anisotropic heterogeneous material. Pressure fluctuations and local stress concentrations occur mostly near the boundaries of grains that have large orientation differences. As a consequence, the crystallographic microstructure may have a significant effect on rolling contact fatigue life unless grains are very small relative to the Hertzian contact. However, to the contrary, the influence of crystallographic microstructure on the film thickness distribution under the considered steady state conditions is very small.