Abnormal interactions between high-speed edge dislocation and microvoid in BCC metals

被引:19
作者
Bao, Qifan [1 ]
Huang, MinSheng [1 ,2 ,3 ]
Zhu, Yaxin [1 ,2 ]
Zhao, Lv [1 ,2 ]
Li, Zhenhuan [1 ,2 ]
机构
[1] Huazhong Univ Sci & Technol, Sch Aerosp Engn, Dept Mech, Wuhan 430074, Peoples R China
[2] Hubei Key Lab Engn Struct Anal & Safety Assessmen, Wuhan 430074, Peoples R China
[3] State Key Lab Mat Proc & Die & Mould Technol, Wuhan 430074, Peoples R China
基金
中国国家自然科学基金;
关键词
High-speed dislocation; Subsonic; Dislocation-void interaction; Dynamic effect; DYNAMICS; PLASTICITY; CRYSTAL; MODEL; IRON;
D O I
10.1016/j.ijplas.2021.103125
中图分类号
TH [机械、仪表工业];
学科分类号
0802 ;
摘要
The interaction between a high speed edge dislocation and a microvoid has been investigated by molecular dynamics (MD) simulations in BCC crystals of Ta, Fe, V and W in the present work. The focus is placed on the dynamic effect on the dislocation-microvoid interaction. Three interaction scenarios different from static cases, i.e., repeated dislocation oscillations around microvoids, dislocation depinning from microvoid like releasing an elastic slingshot, and formation of abnormal "pull forward" dislocation configuration, have been found for the first time. The "repeated oscillations" can be attributed to the dislocation line tension and dynamic effect, which is analogous to under-damped mechanical oscillator system. For the "releasing slingshot" case, the dislocation first bows out after breaking away from the microvoid, and then a stable "drag backward" dislocation configuration is formed. When further increasing the applied shear stress, the dislocation can accelerate to subsonic speed of roughly0.7CT, with CT being the transverse sound speed, leading to a stable "pull forward" configuration. These different dislocation configurations are closely related to the formation of superjog driven by the dislocation-microvoid interaction. By careful analysis, it is found that the variation of relative mobility between the original edge dislocation on the (110) plane and the superjog segments on the (112) plane with shear stresses perfectly coincides with the above three dislocation configurations. In fact, when the applied shear stress is high enough and the dislocation speed is subsonic, the friction stress on the superjog segments turns to be smaller than that of the original edge dislocation, resulting in the formation of abnormal "pull forward" configuration.
引用
收藏
页数:13
相关论文
共 39 条
[11]   Void-induced cross slip of screw dislocations in fcc copper [J].
Hatano, Takahiro ;
Kaneko, Tetsuya ;
Abe, Yousuke ;
Matsui, Hideki .
PHYSICAL REVIEW B, 2008, 77 (06)
[12]   Energy radiation and limiting speeds of fast moving edge dislocations in tungsten [J].
Jin, Zhaohui ;
Gao, Huajian ;
Gumbsch, Peter .
PHYSICAL REVIEW B, 2008, 77 (09)
[13]   Relativistic effect inducing drag on fast-moving dislocation in discrete system [J].
Kim, Soon ;
Kim, Hokun ;
Kang, Keonwook ;
Kim, Sung Youb .
INTERNATIONAL JOURNAL OF PLASTICITY, 2020, 126 (126)
[14]   Prediction of the shear strength of aluminum with 0 phase inclusions based on precipitate statistics, dislocation and molecular dynamics [J].
Krasnikov, Vasilii S. ;
Mayer, Alexander E. ;
Pogorelko, Viktor V. .
INTERNATIONAL JOURNAL OF PLASTICITY, 2020, 128
[15]   Strongly correlated breeding of high-speed dislocations [J].
Li, Qing-Jie ;
Li, Ju ;
Shan, Zhi-Wei ;
Ma, Evan .
ACTA MATERIALIA, 2016, 119 :229-241
[16]   Dislocation jumping over the sound barrier in tungsten [J].
Li, QK ;
Shi, SQ .
APPLIED PHYSICS LETTERS, 2002, 80 (17) :3069-3071
[17]   Glide mobility of the 1/2[1101(001) edge dislocation in UO2 from molecular dynamics simulation [J].
Lunev, A. V. ;
Kuksin, A. Yu. ;
Starikov, S. V. .
INTERNATIONAL JOURNAL OF PLASTICITY, 2017, 89 :85-95
[18]   Coupling continuum dislocation transport with crystal plasticity for application to shock loading conditions [J].
Luscher, D. J. ;
Mayeur, J. R. ;
Mourad, H. M. ;
Hunter, A. ;
Kenamond, M. A. .
INTERNATIONAL JOURNAL OF PLASTICITY, 2016, 76 :111-129
[19]   Mechanical and energetical analysis of molecular dynamics simulations of dislocation-defect interactions [J].
Monnet, Ghiath .
ACTA MATERIALIA, 2007, 55 (15) :5081-5088
[20]   Supersonic dislocations observed in a plasma crystal [J].
Nosenko, V. ;
Zhdanov, S. ;
Morfill, G. .
PHYSICAL REVIEW LETTERS, 2007, 99 (02)