Effects of phosphorus additions on microwave sintering properties of ultrafine WC-10Co cemented carbides

Abstract

Using the microwave sintering technology, the effects of phosphorus (P) additions on the microstructure and properties of the ultrafine WC-10Co alloys were investigated. The experimental results show that with only 0.3wt% P additions, full density WC-10Co cermets were obtained at temperature of 1250 °C, which is 70 °C lower than that of the undoped counterparts. Lower sintering temperature can result in finer WC grain growth; therefore, the P-doped WC-10Co alloys exhibited higher hardness than the undoped ones. But at the same time, P doping could lead to sacrifice of fracture toughness of WC-10Co cemented carbides.

Keywords

microwave sintering / cemented carbides / ultrafine hardmetals / phosphorus / grain growth inhibitor

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