首页 | 本学科首页   官方微博 | 高级检索  
     


Atomistic simulation of the point defects in B2-type MoTa alloy
Authors:Jian-Min Zhang  Fang Wang  Vincent Ji
Affiliation:a College of Physics and Information Technology, Shaanxi Normal University, Xian 710062, Shaanxi, PR China
b State Key Laboratory for Mechanical Behavior of Materials, Xian Jiaotong University, Xian 710049, Shaanxi, PR China
c ICMMO/LEMHE UMR 8182, Université Paris-Sud 11, 91405 Orsay Cedex, France
Abstract:The formation and migration mechanisms of three different point defects (mono-vacancy, anti-site defect and interstitial atom) in B2-type MoTa alloy have been investigated by combining molecular dynamics (MD) simulation with modified analytic embedded-atom method (MAEAM). From minimization of the formation energy, we find that the anti-site defects MoTa and TaMo are easier to form than Mo and Ta mono-vacancies, while Mo and Ta interstitial atoms are difficult to form in the alloy. In six migration mechanisms of Mo and Ta mono-vacancies, one nearest-neighbor jump (1NNJ) is the most favorable due to its lowest activation and migration energies, but it will cause a disorder in the alloy. One next-nearest-neighbor jump (1NNNJ) and one third-nearest-neighbor jump (1TNNJ) can maintain the ordered property of the alloy but require higher activation and migration energies, so the 1NNNJ and 1TNNJ should be replaced by straight [1 0 0] six nearest-neighbor cyclic jumps (S[1 0 0]6NNCJ) or bent [1 0 0] six nearest-neighbor cyclic jumps (B[1 0 0]6NNCJ) and [1 1 0] six nearest-neighbor cyclic jumps ([1 1 0]6NNCJ), respectively. Although the migrations of Mo and Ta interstitial atoms need much lower energy than Mo and Ta mono-vacancies, they are not main migration mechanisms due to difficult to form in the alloy.
Keywords:61.66.Dk   61.72.Bb   67.80.Mg
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号