摘要
采用多体势 ,用分子动力学方法对 Ti Al中空位、反位原子、间隙原子以及小尺寸空位团(N0 =2 ,3,4 )进行计算机模拟研究 ,分析讨论了空位团最稳定的构形 ,研究了空位团对单空位迁移的影响 .计算结果表明 :Ti Al中钛空位的形成能大于铝空位的形成能 ;热平衡状态下存在大量的钛反位原子 ;间隙原子形成能较大 ,为空位形成能的 2 ,3倍 ;在稳定存在的空位团中 ,每个空位都尽可能地与其他空位保持最近邻关系 ;已有的空位团可作为空位的凝聚中心具有捕获或吸收附近空位的能力 。
The molecular dynamics method with a many body potential is used to investigate the vacancy, antisite defect, interstitial and small vacancy clusters in TiAl. The most stable configuration of a vacancy cluster and its effect on the migration of a nearby vacancy are simulated and discussed. The results show that the formation energy of Ti vacancy is bigger than that of Al vacancy in TiAl, and there are many Ti anti site defects in thermal equilibrium, and the formation energy of interstitial is much bigger, i.e. is 2 to 3 times that of vacancy. In the most stable configuration, each vacancy endeavors to form a nearest neighbor relationship with other vacancies. An existing vacancy cluster has the ability of trapping or absorbing a nearby vacancy.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2001年第5期30-35,共6页
Journal of Lanzhou University(Natural Sciences)
基金
国家自然科学基金 (5 9895 15 0 )资助项目
