Excellent strength-ductility combination in the absence of twinning in a novel single-phase VMnFeCoNi high-entropy alloy

Abstract

In the field of single-phase high-entropy alloys (HEAs), most research has been limited to a few systems. For example, among the face-centered cubic (FCC) alloys, the Cantor alloy (equiatomic CrMnFeCoNi) and its derivatives have received the greatest attention. Subsequent attempts to produce quinary single-phase FCC HEAs have been largely unsuccessful, except for a few examples such as NiCuPdPtAu (the Freundenberger alloy). In the present work, we show for the first time that the equiatomic VMnFeCoNi alloy, which is not a subset of any previously reported system, has been successfully synthesized as single-phase FCC, with homogeneous composition and random texture. Its room-temperature tensile properties were investigated and compared with those of CrMnFeCoNi. VMnFeCoNi exhibits superior tensile properties to CrMnFeCoNi in terms of yield strength, work hardening behavior, ultimate tensile strength, and ductility. Surprisingly, its remarkable strength-ductility combination was achieved despite the absence of deformation twinning, as confirmed by transmission electron microscopy.