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arXiv · 2404.00564

First Principles Studies of Stacking Fault Energies in Ternary Magnesium Alloys

Qiwen Qiu·Stephen Yue·Jun Song
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Abstract

Magnesium (Mg) alloys have emerged as promising materials due to their low density and high strength-to-weight ratio, offering a wide range of applications across multiple industries. Nevertheless, the inherent brittleness of Mg alloys poses a significant hurdle, necessitating innovative approaches to enhance their mechanical performance. Among the various strategies, manipulating stacking fault energy (SFE) has been a key focus, although primarily within the realm of binary alloys. This study investigates SFE in Mg alloys, focusing on ternary compositions. Utilizing first-principles DFT calculations, we analyze solute interactions and their influence on SFE, particularly in Mg-Al-X and Mg-Zn-X configurations. Predictive models are developed for estimating SFE effects, revealing solute pairs that mimic rare earth elements and show potential for improved ductility. The findings contribute to fundamental insights into Mg alloy behavior, offering practical directions for designing advanced materials with superior mechanical properties.

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Qiwen Qiu, Stephen Yue, Jun Song. 2024-03-31. First Principles Studies of Stacking Fault Energies in Ternary Magnesium Alloys. https://arxiv.org/abs/2404.00564

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