High-Temperature Tribological Properties of Cu–Ni–Sn/WC Composite Coatings Produced by Laser Cladding

Abstract

High-temperature wear-resistant Cu–Ni–Sn/WC composite coatings were fabricated via laser cladding. The effects of WC–17Co content on the microstructure, microhardness, and high-temperature tribological properties at room temperature to 500 °C were investigated. The results reveal that the addition of WC–17Co enhances the microhardness of the coatings, increasing from 334.8 HV0.2 to 412.4 HV0.2. The friction coefficient initially decreases and then rises with increasing WC–17Co content, while the wear rate displays an opposite trend. The increased temperature promotes a reduction in the wear rate, while exhibiting a little impact on the friction coefficient. At room temperature to 300 °C, abrasive wear is the predominant wear mechanism. However, at high temperatures, the dominant wear mechanism transitions to oxidative wear. The wear resistance is enhanced by the synergistic interaction of WC–17Co particles and a tribo-oxide layer.