单晶铝孔洞生长的分子动力学模拟  

Molecular dynamics simulations of void growth in single crystal aluminum

作　　者：胡晓燕[1] 徐建刚[1] 闫新兴[1] 

机构地区：[1]西安邮电大学理学院,陕西西安710061

出　　处：《兵器材料科学与工程》2012年第6期52-55,共4页Ordnance Material Science and Engineering

基　　金：陕西省教育厅专项科研计划项目(2010JK844)

摘　　要：用分子动力学方法模拟不同晶向单轴加载过程中,单晶铝中微纳米孔洞(约1.6 nm)的生长及周围区域的变形过程。为研究晶向对孔洞生长的影响,对具有相同初始孔洞体积分数的两个晶向进行拉伸加载,并对不同温度影响进行研究。结果表明:A晶向(x-[100],y-[010],z-[001])的形变机制主要是{111}晶面部分位错引起的堆垛层错,B晶向(x-[-110],y-[111],z-[11-2])主要是位错的移动与堆积;B晶向比A晶向的位错成核应力大;B晶向屈服应力比A晶向对温度敏感。The growth and deformation pattern of nano-void （diameter d≈ 1.6 nm）in aluminum single crystals with different orientation were investigated using molecular dynamics simulations. In order to study the influences of orientation on void evolution in single crystals, two orientation with the same initial volume fraction of voids were considered. Investigations of the effects of temperature were also performed. The results of simulation reveal that the main deformation mechanism of orientation A （x- [100], y- [010], z- [001] ） is stacking fault caused by partial dislocation of {111} lattice plane, and of orientation B （x- [110], y-[111], z-[ 112 ] ） is the dislocation motion and pile up. Furthermore, the nucleation stress of dislocation in orientation B is much higher than that of orientation A. The yield strengths for orientation B are much more sensitive to temperature than those for orientation A.

关 键 词：分子动力学模拟 纳米孔洞生长 单晶铝 

分 类 号：O733[理学—晶体学]