Strong trapping and slow diffusion of helium in a tungsten grain boundary

CORC > 金属研究所 > 中国科学院金属研究所

	Strong trapping and slow diffusion of helium in a tungsten grain boundary
	Wang, Xin-Xin ; Niu, Liang-Liang ; Wang, Shaoqing
刊名	JOURNAL OF NUCLEAR MATERIALS
	2017-04-01
卷号	487 页码:158-166
关键词	Grain boundary Helium Segregation Diffusion Tungsten
ISSN号	0022-3115
通讯作者	Niu, LL (reprint author), Beihang Univ, Dept Phys, Beijing 100191, Peoples R China.
中文摘要	We have investigated the segregation, trapping and diffusion of He in a Sigma 3 < 110 >{111} W grain boundary (GB) using combined techniques of ab initio and classical atomistic simulations. We show that, with an average segregation energy of -3.20 eV, the strong He trapping can be attributed to a GB interstitial trapping or a vacancy trapping mechanism, while an average energy barrier of 1.97 eV leads to a slow diffusion of He in the GB plane. We further reveal by molecular dynamics simulations that the He diffusion will be dictated by GB migration through the motion of GB disconnections. Interestingly, we also observe a He-induced GB structural transition in classical simulations. The present work suggests that the GB does not provide fast transport channel for He, providing useful reference for the possible application of polycrystalline W under He irradiation in advanced nuclear fusion reactors. (C) 2017 Elsevier B.V. All rights reserved.
学科主题	Materials Science, Multidisciplinary ; Nuclear Science & Technology
收录类别	SCI
资助信息	National Major Research Program of China [2016YFB0701302]; Informalization Construction Project of Chinese Academy of Sciences during the 11th Five Year Plan Period [INFO-115-b01]; Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (the second phase)
语种	英语
公开日期	2017-08-17
内容类型	期刊论文
源URL	[http://ir.imr.ac.cn/handle/321006/78206]
专题	金属研究所_中国科学院金属研究所
推荐引用方式 GB/T 7714	Wang, Xin-Xin,Niu, Liang-Liang,Wang, Shaoqing. Strong trapping and slow diffusion of helium in a tungsten grain boundary[J]. JOURNAL OF NUCLEAR MATERIALS,2017,487:158-166.
APA	Wang, Xin-Xin,Niu, Liang-Liang,&Wang, Shaoqing.(2017).Strong trapping and slow diffusion of helium in a tungsten grain boundary.JOURNAL OF NUCLEAR MATERIALS,487,158-166.
MLA	Wang, Xin-Xin,et al."Strong trapping and slow diffusion of helium in a tungsten grain boundary".JOURNAL OF NUCLEAR MATERIALS 487(2017):158-166.