Deviation from high-entropy configurations in the atomic distributions of a multi-principal-element alloy

TLDR

Combining multiple elements in near‑equimolar ratios—high‑entropy alloys—has shown great potential for producing exceptional engineering materials that tend to form single phases and exhibit enhanced properties. The study aims to understand elemental distribution and the evolution of configurational entropy during solidification of the Al₁.₃CoCrCuFeNi alloy. This is investigated by analyzing the elemental distribution in the Al₁.₃CoCrCuFeNi model alloy during solidification. The results show that even with elemental segregation, precipitation, chemical ordering, and spinodal decomposition, significant disorder persists due to multi‑element distributions in the major phases, indicating that high‑entropy alloy design can be applied to a wide range of complex materials and that such alloys can maintain enhanced properties despite segregation and ordering.

Abstract

The alloy-design strategy of combining multiple elements in near-equimolar ratios has shown great potential for producing exceptional engineering materials, often known as ‘high-entropy alloys’. Understanding the elemental distribution, and, thus, the evolution of the configurational entropy during solidification, is undertaken in the present study using the Al1.3CoCrCuFeNi model alloy. Here we show that, even when the material undergoes elemental segregation, precipitation, chemical ordering and spinodal decomposition, a significant amount of disorder remains, due to the distributions of multiple elements in the major phases. The results suggest that the high-entropy alloy-design strategy may be applied to a wide range of complex materials, and should not be limited to the goal of creating single-phase solid solutions. Alloys containing multiple elements of equal distributions are known to show enhanced properties as they tend to form single phases. Here, the authors demonstrate that even in cases of elemental segregation and chemical ordering, these alloys can still maintain enhanced properties.