Controlling Friction and Wear with Anisotropic Microstructures in MoN-Coated Surfaces

Abstract

This study considers anisotropic microstructures with typical dimensions of a few 10 µm which have been created on steel surfaces by laser surface texturing (LST). It is shown that the subsequent deposition of thin molybdenum nitride coatings by high-power impulse magnetron sputtering (HiPIMS) leads to surfaces that conserve the surface microstructures and exhibit a remarkably large resistance against mechanical wear. Tribological experiments with steel counter bodies are substantially influenced by the relative orientation of the structures and the wear track. Both friction and wear are shown to be modified by more than 30%, with the main effect being the removal of abrasion particles from the mechanical contact. Experiments with alumina counter bodies that hardly provide wear particles show that the orientation has no effect on the abrasion of the counter body. The novelty of the article lies in the combination of MoN coatings with surface texturing.