Influence of the Cross-Hatched Surface Texture on a Starved Hydrodynamic Linear Contact

Surface roughness and topography are two important parameters that influence the film thickness and friction of a lubricated contact. In many industrial applications, these parameters are imposed by the manufacturing process. This has been the case for the cylinder liner: the honing process creates a specific cross-hatched groove pattern on the cylinder liner surface. Laser surface texturing can produce surfaces with the same type of micro-geometry, but with an increased precision and control. Thus a better compromise between friction losses and oil consumption can be found. For this, it is necessary to understand the effects of the cross-hatched grooves on the film thickness and friction. This paper describes a transient model of a starved hydrodynamic linear contact based on the Reynolds equation. A deterministic description of the surface cross-hatched grooves is used. The results show that the introduction of a surface pattern always reduces the mean film thickness compared to a smooth surface. This reduction depends on parameters like cross-hatch angle and groove density. An appropriate cross-hatched angle can reduce the frictional losses.