Department of Materials Science and Engineering, University of California, Irvine, California 92697, USA.
Department of Mechanical and Aerospace Engineering, University of California, Irvine, California 92697, USA.
Phys Rev Lett. 2020 Nov 13;125(20):205503. doi: 10.1103/PhysRevLett.125.205503.
High-throughput atomistic simulations reveal the unique effect of solute atoms on twin variant selection in Mg-Al alloys. Twin embryo growth first undergoes 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.
高通量原子级模拟揭示了溶质原子对 Mg-Al 合金孪生变体选择的独特影响。孪生胚胎在选择采用哪种孪生变体时，首先经历一个随机潜伏期，然后在不改变所选孪生变体的情况下进入确定性生长阶段。Al 成分的增加促进了界面不连续处形核和钉扎导致的原子级随机潜伏期行为。在超过临界值的组成下，不连续钉扎导致多种孪生变体的选择。
