Defect interaction summary between edge dislocations and <112>-axis symmetric tilt grain boundaries in copper on activation barriers and critical stresses
Defect interaction summary between edge dislocations and <112>-axis symmetric tilt grain boundaries in copper on activation barriers and critical stresses
复制标题
刃位错和缺陷相互作用总结
DOI：
10.1016/j.ijplas.2021.103153
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发表时间：
2022
影响因子：
9.8
通讯作者：
Shibutani Yoji
中科院分区：
文献类型：
--
作者：
Li Li;Liu Lijun;Shibutani Yoji
用<112>原子模拟方法研究了铜中刃型位错与非轴对称倾斜晶界的相互作用。分子动力学模拟和轻推弹性带方法进行了调查的两个缺陷之间的原子反应和所需的激活能触发这样的事件在各种应力或应变状态。结果表明，虽然引入了不同的GB，最常见的情况是位错吸收到GB和传输通过GB。在大多数情况下，一旦这两个晶体学缺陷撞击，主导的部分位错被吸收到GB中。相反，拖尾部分位错在阈值反应应力的确定中起着至关重要的作用。根据过渡态理论，反应能垒与分解的剪切应力或应变状态呈线性关系。恒定活化体积在22- 53 b3的范围内，其中B是Burgers矢量。此外，通过激活体积得到的应变速率敏感性与实验数据吻合较好。
The interactions between edge dislocations and <112>-axis symmetric tilt grain boundaries (GBs) in copper have been investigated by atomistic simulations. Molecular dynamics simulations and the nudged elastic band method were implemented to investigate the atomistic reaction between the two defects and the activation energy required to trigger such an event in various stress or strain states. The results showed that although different GBs were introduced, the most common scenarios were dislocation absorption into the GB and transmission through the GB. In most cases, the leading partial dislocation was absorbed into the GB once these two crystallographic defects impacted. In contrast, the trailing partial dislocation played a crucial role in determination of the threshold reaction stress. From transition state theory, the reaction energy barriers showed a linear relationship with the resolved shear stress or strain state. The constant activation volume was in the range 22–53b3, where b is the Burgers vector. Furthermore, the corresponding strain rate sensitivities obtained through the activation volumes showed good agreement with the experiment data.