Non-equilibrium molecular dynamics simulations of the spallation in Ni: Effect of vacancies

作者：Qiu, Tian; Xiong, Yongnan; Xiao, Shifang; Li, Xiaofan; Hu, Wangyu; Deng, Huiqiu^*

来源：Computational Materials Science, 2017, 137: 273-281.

DOI：10.1016/j.commatsci.2017.05.039

• Spallation
• Vacancy concentration
• Shock wave
• Molecular dynamics simulations

The effects of defects on the fracture resistance of materials have attracted considerable attention recently. In the present work, the vacancy effects on the spallation in single-crystalline Ni are studied by nonequilibrium molecular dynamics simulations. The vacancy concentration ranges from 0% to 2.0%, and the spallation in shock wave loading along three low-index directions ([001], [110], and [111]) is investigated. We found that vacancies provide the sites of nucleation for compression-induce plasticity, and tension stress-induced plasticity plays the key role in void nucleation. Along the [001] direction, the degree of spall damage does not increase with the increase in vacancy concentration; however, along the [110] and [111] directions, it decreases with the increase in vacancy concentration when the vacancy concentration is higher than the threshold value.

• 出版日期2017-9
• 单位湖南大学