Nanocrystalline Ni₂₅Co₂₀Cu₁₀Fe₂₅Mn₂₀ High-Entropy Alloys Prepared by Mechanical Alloying

An Ni₂₅Co₂₀Cu₁₀Fe₂₅Mn₂₀ high-entropy alloy (HEA) was produced using mechanical alloying. Similar to equiatomic NiCoCuFeMn alloy, a face-centered cubic single-phase nanocrystalline HEA was obtained after 28-h milling. The lattice parameter of this new HEA (0.360 nm) was slightly smaller than that of equiatomic alloy (0.361 nm). The crystallite size of the final product was ~ 9 nm, significantly finer than the values reported for the equiatomic HEAs. According to the analysis of the HEA powder particles' deformation behavior, the system operated in a ductile-brittle mode. The thermal behavior of prepared alloy, characterized by differential thermal analysis, was similar from that of equiatomic NiCoCuFeMn alloy. Similar to the equiatomic NiCoCuFeMn, the sluggish diffusion effect was not true for the Ni₂₅Co₂₀Cu₁₀Fe₂₅Mn₂₀ HEA. Studying the magnetic behavior of Ni₂₅Co₂₀Cu₁₀Fe₂₅Mn₂₀ HEA, using vibrating sample magnetometry, confirmed a soft magnetic behavior for this material like an equiatomic alloy.