Mechanical and tribological performance of copper matrix self-lubricating composite prepared by resonant acoustic mixing powder

Abstract

CuNi-WS2 self-lubricating composites with 10 wt% WS2 were fabricated by combining resonant acoustic mixing (RAM) powders and pressureless sintering in an H2 atmosphere. The influence of acceleration, a critical process parameter of RAM, on the microstructures, mechanical and tribological performance of the composites were investigated, then the mechanism of acceleration on the performance of composites was discussed based on the analysis of the morphology and dispersion of WS2. The composite exhibits optimal mechanical and tribological properties at an acceleration of 70 g, with a bending strength of 231 MPa, and the friction coefficient and the wear rate are 0.243 and 9.26 × 10−5 mm3/N·m, respectively. WS2 is primarily dispersed through the composite as small clusters and tiny particles at an acceleration of 70 g. It not only promotes the interfacial reaction of WS2 to generate hard W particles, improving the strength of composites, but also facilitates the formation of compact tribo-film, avoiding massive fractures caused by the fragmentation of large WS2 agglomerations.