Tailoring the stability of {10(1)over-bar2} twins in magnesium with solute segregation at the twin boundary and strain path control
Tailoring the stability of {10(1)over-bar2} twins in magnesium with solute segregation at the twin boundary and strain path control
复制标题
通过孪晶边界处的溶质偏析和应变路径控制来调整镁中 {10(1)over-bar2} 孪晶的稳定性
DOI：
10.1016/j.commatsci.2018.05.035
复制
发表时间：
2018
影响因子：
3.3
通讯作者：
Li Dongyang
中科院分区：
文献类型：
--
作者：
Zhu Heyu;Liu Shan;Liu Ziran;Li Dongyang
摘要镁合金中的{1 0 1 <$2}< 1 0 1 <$1>孪晶通常在室温下受到机械载荷的激活，以适应任意变形。采用第一性原理计算方法研究了孪晶晶界溶质偏聚对{1 0 1 <$2}孪晶稳定性的影响。提出了外应力作用下孪晶能的定义，用以预测在应变作用下孪晶边界有固溶体的孪晶的稳定性。计算结果表明，在边界有无固溶体的情况下，通过施加外应力，可以调整{1 0 1 <$2}孪晶的稳定性，其稳定性取决于应变路径.模型定性地与以前的实验结果相匹配。根据电子功函数（EWF）可以选择有效的溶质原子来替代{1 0 1 2}孪晶晶界上沿着的某些位置的Mg原子，以稳定孪晶。
Abstract {1 0 1¯ 2}< 1 0 1¯ 1> twins in magnesium is commonly activated at the room temperature under mechanical loading to accommodate arbitrary deformation. The effect of solute segregation at twin boundary on the stability of {1 0 1¯ 2} twins was investigated by employing first-principles calculations. A definition of twinning energy under external stress is proposed to predict the stability of twin with solid solutes at twin boundary under strains. The calculations reveal that the stability of {1 0 1¯ 2} twins, which is dependent on the strain path could be tailored by applying external stress with or without solid solutes at boundary. The modeling well matches the previous experimental results qualitatively. Effective solute could be selected based on the electron work function (EWF) to substitute Mg atoms in certain positions along the {1 0 1¯ 2} twin boundary in order to stabilize the twin.