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arXiv · 2605.18219

Short-range order in the CoCrFeMnNi high-entropy alloy from cluster expansion

Wei Chen·Gian-Marco Rignanese·Geoffroy Hautier
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Abstract

We investigate the short-range order (SRO) and phase stability of the equiatomic CoCrFeMnNi high-entropy alloy using cluster expansion supplemented by an eigen-decomposition analysis of the SRO parameters. Our results reveal that the primary ordering behavior is determined by strong Cr-Cr repulsive interactions, complemented by attractive heteroatomic Cr-$X$ pairs in the first nearest-neighbor shell. This chemical affinity is consistent with the emergence of ordered local environments and appears to be a major contributor to the primary order-disorder transition. At lower temperatures, the spectral SRO analysis suggests two additional lower-temperature instabilities: a collective ordering instability and an Fe-rich local clustering instability.

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Wei Chen, Gian-Marco Rignanese, Geoffroy Hautier. 2026-05-18. Short-range order in the CoCrFeMnNi high-entropy alloy from cluster expansion. https://arxiv.org/abs/2605.18219

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