Enhanced magnetisation with increased chromium concentration in FeCoCr_xNi₂Al high-entropy alloy

The present work reports the effect of increasing concentration of antiferromagnetic element Cr in FeCoCr_xNi₂Al (x = 0.5, 1.5) high entropy alloy (HEA) on their magnetic properties. We find that the structure and composition of different phases present in HEA significantly affects its magnetic properties. Interestingly, the sample with Cr concentration x = 1.5 showed two times larger saturation magnetisation as compared to x = 0.5. Furthermore, the magnetisation versus temperature response shows multi-phase character and exhibits distinct behaviour in low temperature and high temperature regime in both the samples. The obtained soft ferromagnetic behaviour of these HEA is crucial for the development of a new class of HEA for various applications.