Microstructure and properties of WC-12Co cemented carbide fabricated via selective electron beam melting

In this study, we investigated the microstructure, mechanical and wear properties of WC-12Co cemented carbides fabricated via selective electron beam melting (SEBM). Subsequently, some of the samples were treated with vacuum sintering heat treatment at 1400 °C at 5 MPa under argon. Apart from the WC and Co phases, the Co 3 W 3 C phase was found in the SEBM-fabricated cemented carbides. After heat treatment, WC grain growth and the Co 6 W 6 C phase appeared. Interestingly, η phase content decreased after heat treatment. The longitudinal section of the samples exhibited a layered structure, which was interlaced with coarse and fine WC. A compressive strength value of 1839 MPa was achieved after heat treatment, while the compressive strength without heat treatment was 1770 MPa. The nanoindentation test showed that the microhardness of the heat-treated samples decreased compared to the SEBM- fabricated sample (18.92 GPa). The SEBM-fabricated WC-12Co cemented carbides had an average friction coefficient of 0.548 and a wear rate of 0.0055 mm 3 , which increased by 59.7% and 142% in the samples after heat treatment. • WC-12Co alloys were prepared by SEBM and heat treatment. • Co 3 W 3 C phases was found in the SEBM-fabricated WC-12Co cemented carbides. • The hardness and wear resistance of the WC-12Co declined after heat treatment, due to WC grain growth, stress relief.