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arXiv · 2310.12078

Deformation Mechanisms in High Entropy Alloys: A Minireview of Short-Range Order Effects

Novin Rasooli·Wei Chen·Matthew Daly
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Abstract

The complex atomic scale structure of high entropy alloys presents new opportunities to expand the deformation theories of mechanical metallurgy. In this regard, solute-defect interactions have emerged as critical piece in elucidating the operation of deformation mechanisms. While notable progress has been made in understanding solute-defect interactions for random solute arrangements, recent interest in high entropy alloys with short-range order adds a new layer of structural complexity for which a cohesive picture has yet to emerge. To this end, this minireview synthesizes the current understanding of short-range order effects on defect behavior through an examination of the key recent literature. This analysis centers on the nanoscale metallurgy of deformation mechanisms, with the order-induced changes to the relevant defect energy landscapes serving as a touchstone for discussion. The topics reviewed include dislocation-mediated strengthening, twinning and phase transformation-based mechanisms, and vacancy-mediated processes. This minireview concludes with remarks on current challenges and opportunities for future efforts.

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Novin Rasooli, Wei Chen, Matthew Daly. 2023-10-18. Deformation Mechanisms in High Entropy Alloys: A Minireview of Short-Range Order Effects. https://doi.org/10.1039/d3nr05251f

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