Microstructure, Mechanical Properties, and Oxidation Behavior of Al_xCr_0.4CuFe_0.4MnNi High Entropy Alloys

Al_xCr_0.4CuFe_0.4MnNi (x = 0, 0.1, 0.2, 0.3, 0.4) high entropy alloys (HEAs) were prepared by copper-mold casting. The effects of Al were investigated on the microstructure, tensile properties and oxidation behavior of these HEAs. It was shown that the addition of Al resulted in the formation of BCC and ordered BCC phases. The compositional heterogeneity between dendrites and interdendrites was alleviated when the content of Al was small. The mechanical properties of HEAs have been remarkably improved by the addition of Al. Considering the low cost and good mechanical properties, this kind of HEAs is rather competitive among HEAs for engineering application as structural materials. In this work, it was also shown that the oxidation resistance of current HEAs was significantly improved by the addition of Al.