Microstructural investigation of oxidized complex refractory high entropy alloys

The microstructures of two newly developed refractory high entropy alloys were examined after isothermal oxidation at 1200°C for 10 hours. Scanning electron microscope analysis showed the formation of aluminosilicate layer on the sample surface, and the structure of oxide layers appears to be greatly affected by the content of Al and V. With increased Al content and decreased V content, the size of pores within the internal oxidation zone was decreased. Future directions to improve the oxidation resistance of complex refractory alloys were proposed.