钛铝金属间化合物中位错相互作用的原子尺度模拟  

Atomistic Simulations of Dislocation Interaction in Intermetallic TiAl

作　　者：王皞[1] 徐东生[1] 杨锐[1] 

机构地区：[1]中国科学院金属研究所,沈阳110016

出　　处：《科研信息化技术与应用》2011年第6期99-103,共5页E-science Technology & Application

基　　金：科技部973项目(2006CB605104);自然科学基金项目(50911130367;50631030)

摘　　要：本文对钛铝金属间化合物中的位错偶湮灭和位错反应进行原子尺度模拟研究。结果显示,位错偶并未发生完全的湮灭,而是转变为依赖于位错偶高度和温度的多种稳定构型,低温下形成空腔、垂直和倾斜等构型,高温下形成空位团簇等复杂构型;位错的直接相互作用可以产生高浓度的、多种形式的空位,自间隙原子和层错偶极子等缺陷。这些位错相互作用的产物可能成为运动位错的障碍,或者与位错发生反应,从而对后续塑性变形产生重要影响。In the present paper, dislocation dipole annihilation and dislocation reaction are investigated in the intermetallic TiAI with atomic-scale simulations. It is shown that dipoles do not simply annihilate, instead they transform into various stable configurations depending on their height and temperature. Hollows, vertical and inclined configurations are formed at low temperature, while vacancy clusters at high temperature. The direct interactions between dislocations result in vacancies, interstitials and faulted dipoles at high density. Such products after dislocation interaction may become obstacles of moving dislocations, or react with them, hence influencing subsequent plastic deformation.

关 键 词：钛铝 位错 位错偶 点缺陷 原子模拟 

分 类 号：TG146.23[一般工业技术—材料科学与工程]