Interfacial bonding and wear resistance of W, Mo, and MoS2 reinforced graphite/copper composites via microwave sintering

Abstract

In the present work, W, Mo, and MoS₂ reinforced graphite/copper composites were prepared using microwave sintering. By focusing on the copper matrix and graphite reinforcement, W and Mo elements were introduced into the copper matrix, while MoS₂ was doped into the graphite. During sintering, carbide pinning phases and Cu-Mo-S transition layers were formed at the graphite/copper interface, enhancing the interfacial bonding between graphite and copper. The effects of sintering time on the microstructure and properties of the composites were investigated, including their tribological performance under varying friction loads and linear speeds. A sintering time of 60 min was observed to lead to composite materials with improved microstructural properties, specifically a higher density of pinning phases and Cu-Mo-S transition layers, as well as a uniform microstructure. Significant improvements were observed in density, hardness, electrical, and thermal conductivity. Under a friction load of 4 N and a sliding speed of 1.7 m/s, the wear rate of the composites was only 4.52 × 10⁻⁸ cm³ N⁻¹ m⁻¹. These findings provide a reference for improving the interface of graphite/copper composites and their application in the field of friction and wear.