首 页  |  期刊简介  |  投稿须知  |  专家审稿  |  编者登陆  |  公告信息  |  联系我们
 
α-Fe中氦泡阻碍位错移动硬化的分子动力学研究
Molecular dynamics study of hardening induced by helium bubbles impeding edge dislocation motion in α-Fe
摘要点击 69  全文点击 14  投稿时间:2018-02-02  修订日期:2018-02-26
查看全文  查看/发表评论  下载PDF阅读器
DOI编号  
中文关键词   氦泡  刃位错  氦空位比例  分子动力学
英文关键词   Helium bubble  edge dislocation  He/V ratio  molecular dynamics
基金项目   U1730123
作者单位E-mail
刘星 中国科学技术大学 fixed@mail.ustc.edu.cn 
时靖谊 深圳大学新能源研究中心  
彭蕾 中国科学技术大学  
中文摘要
    基于周期性位错阵列模型,利用分子动力学方法,研究了α-Fe中1/2a0<111>{110}刃位错与3 nm氦泡的相互作用导致硬化的过程,重点研究了不同温度下(300 K和623 K),氦空位比例对位错与3 nm氦泡作用机制影响的差异性。研究结果表明,当氦空位比例在0~1之间变化时,氦空位比例的变化对临界剪切应力的影响微弱,当氦空位比例在1~1.5之间变化时,氦泡内氦原子的数量的增加,临界剪切应力随之降低。氦空位比例升高至1.75时,高温623 K与室温相比,临界剪切应力反常升高,原因是高温引起的位错与氦泡的排斥机制:氦泡严重超压,与位错接触瞬间,沿位错拉伸侧踢出自间隙原子团簇,被位错吸收后产生割阶;由于位错割阶与超压氦泡同为压应力场,割阶被氦泡强烈排斥反弹。
英文摘要
    Abstract: The interaction between 1/2a0<111>{110} edge dislocation and 3.0 nm helium bubble with various Helium-to-vacancy ratios (He/V) and temperatures (300 K and 623 K) in α-Fe were studied by using molecular dynamics based on the periodic arrays of dislocations model. The results show that the release stress of dislocation weakly depends on He/V ratios ranging from 0 to 1; when He/V ratio varies from 1.0 to 1.5, increasing the number of helium atoms in the helium bubble has positive effects on the climbing of dislocation; for the helium bubble (He/V = 1.75), when the temperature rises from 300 K to 623 K, the increase of the bubble pressure caused by the increase of temperature changes the interaction mechanism and caused the increase of CRSS. A repel mechanism of dislocation and helium bubble interaction is proposed to elucidate the effect of temperature. When the helium bubble is heavily over-pressured, the edge dislocations absorbs the interstitials and clusters which are punched out from the bubble, thus forms a superjog and is repelled from the bubble since there both are compressive stress fields around the dislocation jog and over-pressured helium bubble.

您是第 2909901 位访客
版权所有 @ 2006《原子与分子物理学报》编辑部
通讯地址:四川省成都市武侯区四川大学收发服务中心378号信箱   邮编:610065
电话:3094757965  传真:  E-mail:jamp@scu.edu.cn
本系统由北京勤云科技发展有限公司设计