摘要
Many of our previous studies have discussed the shock response of symmetrical grain boundaries in iron bicrystals.In this paper, the molecular dynamics simulation of an iron bicrystal containing Σ3 [110] asymmetry tilt grain boundary(ATGB) under shock-loading is performed. We find that the shock response of asymmetric grain boundaries is quite different from that of symmetric grain boundaries. Especially, our simulation proves that shock can induce migration of asymmetric grain boundary in iron. We also find that the shape and local structure of grain boundary(GB) would not be changed during shock-induced migration of Σ3 [110] ATGB, while the phase transformation near the GB could affect migration of GB. The most important discovery is that the shock-induced shear stress difference between two sides of GB is the key factor leading to GB migration. Our simulation involves a variety of piston velocities, and the migration of GB seems to be less sensitive to the piston velocity. Finally, the kinetics of GB migration at lattice level is discussed. Our work firstly reports the simulation of shock-induced grain boundary migration in iron. It is of great significance to the theory of GB migration and material engineering.
Many of our previous studies have discussed the shock response of symmetrical grain boundaries in iron bicrystals.In this paper, the molecular dynamics simulation of an iron bicrystal containing Σ3 [110] asymmetry tilt grain boundary(ATGB) under shock-loading is performed. We find that the shock response of asymmetric grain boundaries is quite different from that of symmetric grain boundaries. Especially, our simulation proves that shock can induce migration of asymmetric grain boundary in iron. We also find that the shape and local structure of grain boundary(GB) would not be changed during shock-induced migration of Σ3 [110] ATGB, while the phase transformation near the GB could affect migration of GB. The most important discovery is that the shock-induced shear stress difference between two sides of GB is the key factor leading to GB migration. Our simulation involves a variety of piston velocities, and the migration of GB seems to be less sensitive to the piston velocity. Finally, the kinetics of GB migration at lattice level is discussed. Our work firstly reports the simulation of shock-induced grain boundary migration in iron. It is of great significance to the theory of GB migration and material engineering.
作者
张学阳
王昆
陈军
胡望宇
祝文军
肖时芳
邓辉球
蔡孟秋
Xueyang Zhang;Kun Wang;Jun Chen;Wangyu Hu;Wenjun Zhu;Shifang Xiao;Huiqiu Deng;Mengqiu Cai(Department of Applied Physics,School of Physics and Electronics,Hunan University,Changsha 410082,China;Laboratory of Computational Physics,Institute of Applied Physics and Computational Mathematics,Beijing 100088,China;Center for Applied Physics and Technology,Peking University,Beijing 100087,China;College of Materials Science and Engineering,Hunan University,Changsha 410082,China;National Key Laboratory of Shock Wave and Detonation Physics,Institute of Fluid Physics,Mianyang 621900,China)
基金
Project supported by the Fundamental Research for the Central Universities of China
the National Key Laboratory Project of Shock Wave and Detonation Physics of China
the Science and Technology Foundation of National Key Laboratory of Shock Wave and Detonation Physics of China
the National Key R&D Program of China(Grant No.2017YFB0202303)
the National Natural Science Foundation of China(Grant Nos.51871094,51871095,51571088,NSFC-NSAF U1530151,and U1830138)
the Natural Science Foundation of Hunan Province of China(Grant No.2018JJ2036)
the Science Challenge Project of China(Grant No.TZ2016001)
