Low activation high entropy alloys for next generation nuclear applications

Abstract

An integrated experimental and molecular dynamics approach was used for developing low-activation high entropy alloys, potentially attractive for next generation nuclear reactor applications. These alloys were based on the concept of high entropy phase formation from a palette of elements with intrinsic low activity, namely Ta–Ti–V–Zr–X (X = Hf or W), with constituents in equimolar proportions. Molecular dynamics predicted homogenous alloy formation for Ta–Ti–V–Zr–Hf. In contrast, a tendency for Ta–W atomic-pair clustering was seen for Ta–Ti–V–Zr–W, in agreement with microstructure after melt-casting and homogenization. Both alloys showed stable microstructure with high hardness, which was retained up to 300 °C.