Effect of Micro-Textures on the Surface Interaction of WC+Co Alloy Composite Coatings

Abstract

The surface properties of alloys can be improved by coating their surfaces and adding a micro-texture. The effect on the surface properties of alloy composite coatings of adding a textured surface has not been addressed in previous studies. In this study, a micro-texture was added to the surface of a WC+Co alloy AlCrN/AlTiSiN composite coating. The influence of the micro-texture’s geometric parameters on the surface properties of the composite coating and its lifespan were studied in detail. First, the surface hardness and phases of various micro-textured composite coatings were analyzed to explore the effect of different micro-texture parameters on the surface properties. Then, a friction and wear test was conducted to establish a model that can predict the lifespan of a micro-texture and the influence of different micro-texture parameters on the surface friction of the composite coating. After that, the wear pattern of the composite coating and the relative action of the micro-texture were analyzed on the basis of the visible wear morphology. The results show that using a laser to add a micro-texture to the surface of a composite coating creates a hardened layer that increases the coating’s surface hardness. Analysis of the surface phases of the composite coating showed that there are three principal types of grain on the surface, namely WC, CrN and TiN, with WC having the largest grain size. The main kind of wear on the surface of the composite coating was found to be abrasive wear, which can be reduced by the addition of a micro-texture.