Molecular dynamics simulation of grain boundary plasticity in magnesium and solid-solution magnesium alloys
Molecular dynamics simulation of grain boundary plasticity in magnesium and solid-solution magnesium alloys
复制标题
DOI：
10.1016/j.commatsci.2013.04.043
复制
发表时间：
2013-09
影响因子：
3.3
通讯作者：
H. Somekawa;T. Mukai
中科院分区：
文献类型：
--
作者：
H. Somekawa;T. Mukai
采用两种不同的[1−10 0]对称倾斜晶界模型(Σ2 5，倾角θ=2 3°和Σ10，θ=1 78°)，用分子动力学模拟方法研究了镁合金晶界的变形行为。由于变形过程中内能的降低，两种模型都发生了晶界迁移。晶界变形机制为孪晶诱导的晶界迁移。晶界的迁移受晶界结构的影响，在高能的晶界上，晶界的迁移得到加强。溶质原子如铝和银的加入抑制了晶界迁移。研究发现，银原子比铝原子更能有效地抑制。这些行为在分子动力学模拟和实验中都有发生。
The deformation behavior at the grain boundary was investigated by the molecular dynamics simulation using two models based on different kinds of [1−100] symmetric tilt boundaries (Σ25 with a tilt angle ofθ= 23° and Σ10 withθ= 78°) in magnesium. Grain boundary migrations occurred in both models due to the reduction in the internal energy during deformation. The deformation mechanism at the grain boundary was shown to be the twinning induced grain boundary migration. The grain boundary migration was affected by the grain boundary structures, and it was enhanced in the grain boundaries with high energies. On the other hand, the grain boundary migration was suppressed by the addition of solute atoms, i.e., aluminum and silver. The silver atoms were found to be more effective for suppression than the aluminum atoms. These behaviors occurred in both the molecular dynamics simulation and the experiments.