Soft Magnetic High Entropy FeCoNiCuMn Alloy with Excellent Ductility and High Electrical Resistance

The equiatomic FeCoNiCuMn high entropy alloy (HEA) was prepared by vacuum arc-melting under argon atmosphere, and the as-cast alloy was subsequently annealed at 850 degrees C and 1000 degrees C for 2 and 12 h. The annealing effects on the microstructure, magnetic, electrical, and mechanical properties were investigated. Based on the microstructural analysis, three major phases were found in different conditions; (Fe, Co)-rich phase, Cu-rich phase, and homogenized solid solution phase. This HEA showed excellent soft magnetic properties (proper saturation magnetization (40 emu/g), low coercivity (7 Oe) and low magnetic remanence ratio (0.03)) and high electrical resistivity (287 mu Omega.cm) with proper strength and good ductility (41%). All these properties together make FeCoNiCuMn HEA better than that of the most reported soft magnet HEAs, and it can be used as a soft magnetic material in the future. Graphic Abstract

Automated summary

In this study, equiatomic FeCoNiCuMn high entropy alloy was prepared and its microstructure and properties were improved by annealing. The alloy exhibited good soft magnetic properties and high electrical resistivity, along with proper strength and ductility.