Adopting CoCrNi medium-entropy alloy (MEA) with high strength and toughness as the binder metal can be a solution for the property improvement of cermets. To explore the feasibility of CoCrNi MEA as the binder and optimize the sintering process, contact angle evolutions between liquid equiatomic CoCrNi alloy and binderless TiC_0.4N_0.6 substrate under high purity Ar and vacuum conditions were tested by a sessile drop method. Microstructure and composition changes of the alloy system after testing were observed and analyzed. The results show that the initial contact angles and their corresponding temperatures under Ar and vacuum are 20.8° (1415 °C) and 20.6° (1447 °C), respectively. In the substrate, a structure of CoCrNi- gradient binder phase and hard phase is formed. Different from the Ar situation, under a vacuum condition, during the 1450 °C dwell stage, liquid CoCrNi overflows along the surface of the substrate, and its diffusion and penetration ability in the substrate is distinctly weakened. A noteworthy advantage of Ar atmosphere for the liquid phase sintering stage of this alloy system is revealed. Wetting behavior of TiC_0.4N_0.6 and Ni system is adopted for the comparison. CoCrNi MEA is proved to be an adequate binder metal for TiCN-based cermets

采用具有高强度和韧性的CoCrNi中熵合金（MEA）作为粘结剂金属可以提高金属陶瓷的性能。为了探索CoCrNi MEA作为粘结剂的可行性并优化烧结工艺，液态等原子CoCrNi合金与无粘结剂TiC _0.4 N _0.6的接触角演变通过无滴法测试了高纯度Ar和真空条件下的基底。观察并分析了合金体系的微观组织和组成变化。结果表明，在Ar和真空下，初始接触角及其相应的温度分别为20.8°（1415°C）和20.6°（1447°C）。在衬底中，形成CoCrNi-梯度粘结剂相和硬质相的结构。与Ar情况不同，在真空条件下，在1450°C的保压阶段，液态CoCrNi沿基材表面溢出，并且其在基材中的扩散和渗透能力明显减弱。揭示了在该合金体系的液相烧结阶段中Ar气氛的显着优点。TiC _0.4 N的润湿行为比较采用_0.6和Ni体系。事实证明，CoCrNi MEA是TiCN基金属陶瓷的合适粘合剂金属