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arXiv · 2004.09086

Magnetically driven short-range order can explain anomalous measurements in CrCoNi

Flynn Walsh·Mark Asta·Robert O. Ritchie
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Abstract

The presence, nature, and impact of chemical short-range order in the multi-principal element alloy CrCoNi are all topics of current interest and debate. First-principles calculations reveal that its origins are fundamentally magnetic, involving repulsion between like-spin Co-Cr and Cr-Cr pairs that is complemented by the formation of a magnetically aligned sublattice of second-nearest-neighbor Cr atoms. Ordering models following these principles are found to predict otherwise anomalous experimental measurements concerning both net magnetization and atomic volumes across a range of compositions. In addition to demonstrating the impact of magnetic interactions and resulting chemical rearrangement, the possible explanation of experiments would imply that short-range order of this type is far more prevalent than previously realized.

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Flynn Walsh, Mark Asta, Robert O. Ritchie. 2021-03-31. Magnetically driven short-range order can explain anomalous measurements in CrCoNi. https://doi.org/10.1073/pnas.2020540118

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