Direct atomistic modeling of solute drag by moving grain boundaries
Direct atomistic modeling of solute drag by moving grain boundaries
复制标题
通过移动晶界对溶质阻力进行直接原子建模
DOI：
10.1016/j.actamat.2020.07.052
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发表时间：
2020
期刊：
影响因子：
9.4
通讯作者：
Mishin, Y.
中科院分区：
文献类型：
--
作者：
Koju, R.K.;Mishin, Y.
我们表明，分子动力学（MD）模拟能够再现溶质偏析的气氛中移动晶界（GB）的阻力。虽然晶格扩散在MD时间尺度上被冻结，但加速的GB扩散提供了足够的原子迁移率，以允许分离的原子跟随移动的GB。这一发现打开了研究溶质拖曳效应的原子精度使用MD方法的可能性。我们表明，移动GB激活扩散，并改变其运动过程中扫描的晶格区域中的短程顺序。它还表明，一个移动的GB拖动的气氛中的非平衡空位，加速扩散周围的晶格区域。
We show that molecular dynamics (MD) simulations are capable of reproducing the drag of solute segregation atmospheres by moving grain boundaries (GBs). Although lattice diffusion is frozen out on the MD timescale, the accelerated GB diffusion provides enough atomic mobility to allow the segregated atoms to follow the moving GB. This finding opens the possibility of studying the solute drag effect with atomic precision using the MD approach. We demonstrate that a moving GB activates diffusion and alters the short-range order in the lattice regions swept during its motion. It is also shown that a moving GB drags an atmosphere of non-equilibrium vacancies, which accelerate diffusion in surrounding lattice regions.