Effect of Al_xCoCrFeNi High-Entropy Alloy Binder on Microstructure and High-Temperature Oxidation Resistance of Ti(C,N)-Based Cermets

Ti(C, N)-based cermets were prepared by low-pressure sintering with Al_xCoCrFeNi high-entropy alloy (x=0, 0.5, 1, molar ratio) as the binder, and the effects of Al_xCoCrFeNi high-entropy alloy binder on the microstructure and high-temperature oxidation resistance of cermets were investigated. The results show that the prepared cermets were mainly composed of Ti(C, N) phase with face-centered cubic (FCC) structure and high-entropy alloy binder phase with FCC structure, and the transformation from body-centered cubic (BCC) structure phase to FCC structure phase occurred in Al_0.5CoCrFeNi and AlCoCrFeNi high-entropy alloys during high-temperature sintering. The cermets all had a typical core-ring structure, and there were more pores in the cermets prepared with AlCoCrFeNi high-entropy alloy binder. After oxidizing at 1 000℃ for 6 h, the mass gains per unit area of cermets prepared with CoCrFeNi, Al_0.5CoCrFeNi, and AlCoCrFeNi high-entropy alloy binders were 3.58, 2.95, 2.81 mg·cm^-2, respectively, and the cermets prepared with AlCoCrFeNi high-entropy alloy binder had the best high-temperature oxidation resistance.