Preparation of high-performance (ZrHfTaNbTiMo)C–10Co ceramic by SPS using self-synthesized fine high-entropy carbide powders

A series of high-entropy carbide ceramics with high-performance were successfully prepared by SPS using self-synthesized fine high-entropy carbides powders as hard phase and metal Co as the binder. The effects of Ti and/or Mo addition on densification, grain size and mechanical properties of (ZrHfTaNb)C–10Co ceramic were investigated. The results showed that the addition of Mo improved the wettability between the ceramic phase and Co phase, and significantly increased the densification degree of the ceramics. In addition, the average grain size decreased and the microstructure became more uniform after adding Ti and/or Mo. Compared with the mechanical properties of (ZrHfTaNb)C–10Co ceramic, those of (ZrHfTaNbTiMo)C–10Co ceramic were greatly enhanced under the action of high-entropy effect and solid solution strengthening. The hardness and fracture toughness of the (ZrHfTaNbTiMo)C–10Co ceramic achieved the satisfactory values of 20.37 GPa and 8.59 MPa m1/2, respectively.