Influence of copper content on the microstructure and hardness of copper-doped tungsten carbide–cobalt bulk at the elevated temperature

Ultrafine WC–Co cemented carbides doped with 0, 0.5, 1, 1.5 and 2 wt.% Cu were fabricated by the sintering/hot isostatic pressing (sinter–HIP) process for the mixed WC and chemical precipitated Co–Cu powders. The Vickers hardness of cemented carbides was measured at temperatures ranging from room temperature to 800 °C. The Cu-doped WC–Co alloys with the higher proportion of WC hard phase and finer microstructure of the average grain size of 590 nm exhibit the higher hardness at the elevated temperature of 800 °C. The Cu-doped WC–Co cemented carbides have a potential application in machining.

► Cu-doped tungsten carbide-cobalt cemented carbides were fabricated.
► Cu doping can effectively inhibit the dissolution of WC in binder phase and the growth of finer WC particles.
► Cu-doped WC-Co alloys with higher proportion of WC and finer microstructure exhibit higher hardness at elevated temperature.