Taming the TiCN/HEA Interface: Competitive Bonding Unlocks Wettability by Mo 2 C

ABSTRACT The poor wettability between TiCN and many high‐entropy alloys (HEAs) with excellent properties is an important reason why HEAs have not been widely applied in cermets. In this work, Mo 2 C was added to modify poor wettability between TiCN and Ta 0.65 CrCoFeNi 2.0 , endowing them with good wettability. The addition of Mo 2 C induces a competitive bonding mechanism, which promotes the spreading of Ta 0.65 CrCoFeNi 2.0 on the TiCN surface. The improvement of wettability significantly enhances the mechanical properties of the cermets. Compared with the sample without Mo 2 C addition, the flexural strength, Vickers hardness, and fracture toughness of the sample with 8% mass fraction of Mo 2 C added are increased by 63.49%, 90.37%, and 287.17%, respectively. Compared with the sample prepared with AlCrCoFeNi 2.1 (which has inherent good wettability with TiCN) as the binder phase, the Vickers hardness is increased by 36.29% while maintaining the same level of flexural strength and fracture toughness.