Molecular dynamics study of the interactions between the 1/2[111] edge dislocation and the [010] dislocation loop in BCC-Fe
LIN Pandong, NIE Junfeng, LIU Meidan
Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
Abstract：The mechanical behavior of irradiated RPV steel is important for nuclear reactor safety. The property changes are due to microscale dislocation motion and interactions between dislocations and irradiation defects that need to be further understood. This study used molecular dynamics studies to model the interactions between 1/2[111] edge dislocations and [010] dislocation loops in BCC-Fe. The models show the effects of temperature and dislocation loop radius on the interactions and the critical resolved shearing stress (CRSS). The results indicate that the interactions include the formation of mixed dislocation segments, sweeping of the dislocation segments, formation of screw dipoles and edge dislocations breaking away from the dislocation loop. Higher temperatures promote the absorption of dislocation loops and reduce the CRSS. The length of a [010] dislocation segment swept by a 1/2[111] edge dislocation increases with increasing dislocation loop radius which increases the CRSS.
林盼栋, 聂君锋, 刘美丹. BCC-Fe中1/ 2[111]刃型位错与[010]位错环相互作用的分子动力学研究[J]. 清华大学学报（自然科学版）, 2022, 62(12): 2029-2034.
LIN Pandong, NIE Junfeng, LIU Meidan. Molecular dynamics study of the interactions between the 1/2[111] edge dislocation and the [010] dislocation loop in BCC-Fe. Journal of Tsinghua University(Science and Technology), 2022, 62(12): 2029-2034.
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2022, Vol. 62 
