Laser micro-cladding in situ forming textured surface to improve the tribological performance

Abstract

As a branch of laser cladding technology, laser micro-cladding shows unique local selective processing characteristics. Based on laser micro-cladding technology, this article proposes a new method for the in-situ formation of textured surfaces using laser micro-cladding technology. A Ni60/WC/WS2 composite coating was prepared on the cemented carbide substrate using laser micro-cladding technology, and a micro-groove structure was formed in situ. The microstructure, mechanical properties and tribological performance of laser micro-cladding Ni60/WC/WS2 composite coating were studied. The results show that laser micro-cladding technology can effectively prepare periodic controllable micro-textures with micron-sized dimensions, and the thickness of the laser micro-cladding composite coating can reach ∼300 μm. The hardness of composite coating can reach ∼28.48 GPa. The composite coating and micro-texture have a synergistic effect and can effectively improve the tribological properties of the substrate. The LCT sample has the lowest friction coefficient, with an average friction coefficient of ∼0.38. Due to the high hardness of the composite coating, it shows better wear resistance, but the micro-textured edge will cut the steel ball during the friction process, causing the steel ball wear rate of the LCT sample to reach ∼45.86 × 10−5 mm3/Nm. The exploration of laser micro-cladding in-situ forming textured surfaces provides experimental support for the application of cutting tools, brake discs and other mechanical components.