Study on the microwave sintering of the novel Mo–W–Cu alloys

Abstract

In this study, we fabricated a new type of Mo–W–Cu alloys by microwave sintering at a low temperature (1000 °C) in a short time (5 min) and characterized the phases, microstructures, and properties of the alloys. Through calculating the skin depth, it was proved that the microwave field enabled complete penetration of radiation to Mo, W, and Cu particles, thus effectively promoting the diffusion and solid solution among Mo, W, and Cu. XRD and TEM results showed that Mo-W-Cu alloys contained three new phases besides Mo, W, Cu phases, i.e., Mo-W ordered phase, Mo-Cu solid solution, and Cu0.4W0.6 intermetallic compound. It was also found that Mo–W–Cu alloys exhibited better densification and comprehensive properties than Mo-Cu alloys. The number and size of the sintering necks varied with the W content from 10 to 50 wt% among which the optimal microstructure and properties were obtained at 30 wt% W. This study could provide useful guidelines for further research of the densification and properties of microwave sintered Mo-W-Cu alloys.