Microwave sintering of WC-HEA cemented carbide: Sintering process, microstructure and mechanical properties

Microwave sintering is an efficient and green material preparation technology. Ultrafine crystalline WCCoCrFeNiCu cemented carbide were fabricated by microwave sintering using mechanically alloyed highentropy alloy (HEA) as a binder. The effects of the microwave sintering process (sintering temperature, holding time) on grain distribution, microstructure and mechanical properties of WC-HEA cemented carbide were studied. WC-10wt%HEA showed the best mechanical properties as sintered at 1400 degrees C with holding time of 10 min. Its grain size, Vickers hardness and fracture toughness were 273 +/- 6 nm, 17.6 +/- 0.8 GPa, and 8.7 +/- 0.3 MPa & sdot;m1/2, respectively. The delayed diffusion effect of HEA played significant role in inhibiting grain growth, resulting in 38% smaller than that of WC-Co cemented carbide. Improving the wettability of HEA on WC to reduce the porosity of the sintered body is the main challenge in producing cemented carbide tool materials with HEA as a binder.