Microstructure, Phase Relations, and Precipitation Hardening Studies in Mg Containing CoCrCuFeNi High-Entropy Alloys

Abstract

CoCrCuFeNi high-entropy alloys (HEAs) have high ductility owing to their unique two-phase microstructure. Phase relations and microstructure evolution were investigated by scanning electron microscopy coupled with energy dispersive spectrometry and differential thermal analysis. These results contributed to clarifying the formation mechanism of the HEA microstructures. The effects of Mg addition as an alloying element in HEAs were also studied, with respect to precipitation hardening, thereby aiming to obtain strength-ductility balanced HEAs.

Figure 6 Microstructures of the Mg_yCoCrCu_0.55FeNi alloys when y was (a) 0, (b) 0.02, (c) 0.07, and (d) 0.12. R: Cu-rich phase, D: Cu-diluted phase, L: Laves phase.