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arXiv · 2006.15242

Embracing the chaos: Alloying adds stochasticity to twin embryo growth

Yang Hu·Vladyslav Turlo·Irene J. Beyerlein·Subhash Mahajan·Enrique J. Lavernia·Julie M. Schoenung·Timothy J. Rupert
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Abstract

High-throughput atomistic simulations reveal the unique effect of solute atoms on twin variant selection in Mg-Al alloys. Twin embryos first undergo a stochastic incubation stage when embryos choose which twin variant to adopt, and then a deterministic growth stage when embryos expand without changing the selected twin variant. An increase in Al composition promotes the stochastic incubation behavior on the atomic level due to nucleation and pinning of interfacial disconnections. At compositions above a critical value, disconnection pinning results in multiple twin variant selection.

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Yang Hu, Vladyslav Turlo, Irene J. Beyerlein, Subhash Mahajan, Enrique J. Lavernia, Julie M. Schoenung, Timothy J. Rupert. 2020-06-27. Embracing the chaos: Alloying adds stochasticity to twin embryo growth. https://doi.org/10.1103/physrevlett.125.205503

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