Microstructure, Phase Stability, and Oxidation Resistance of (FeCoNi)60Al15Cr25-xTix High-Entropy Alloys

Abstract In the current work, Cr was partially substituted by Ti to discover the effect on the microstructure, phase stability, and properties of the (FeCoNi)60Al15Cr25-xTix ( x = 5, 7.5, 10, atomic percent) alloys, besides, oxidation resistance of the alloys were studied. The (FeCoNi)60Al15Cr25-xTix alloys showed dendrites and interdendritic structures including a mixture of FCC + BCC phases, ordered and disordered. Moreover, Massive nanoparticles and nano-lamellar structures were found in the microstructures of H6T alloys. After annealing at 900°C for 2 h, intermetallic σ phase ( FeCr - type) with a topological structure emerged, and ordered and disordered phase transformation occurred. It is investigated that the designed H6T alloys exhibit an excellent oxidation resistance, and can be applied as a potential candidate of high-temperature material.