(中国科学院 金属研究所,沈阳 110016)
摘 要: 采用分子动力学模拟研究α-Ti中a型刃位错和螺位错的运动特点及其相互作用。对于独立的刃位错和螺位错,发现刃位错滑移时位错芯形态保持不变,而螺位错芯存在两种不同的分解方式:三维分解和基面分解,并导致不同的滑移特征;三维分解的螺位错沿基面滑移时需转变为基面分解,而基面分解的螺位错沿柱面滑移时需转变为三维分解状态,从而导致其开动困难。刃位错与螺位错之间存在多种不同形式的相互作用,其位错反应可形成其他形式复杂的缺陷。
关键字: α-Ti;位错;分子动力学;位错反应
a-type dislocations in α-titanium
(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110006, China)
Abstract:Molecular dynamics simulations were performed for α-titanium to investigate the gliding behavior and interaction of a-type edge and screw disl, ocations. For isolated edge and screw dislocations, the former are found to glide maintaining their characters, whereas for the latter there exist two distinct dissociation patterns, i.e. 3-dimension dissociation and basal-plane dissociation, resulting in distinct gliding behaviors. The 3-dimension dissociated dislocation needs to transform into basal-plane dissociation, in order to initialize gliding on the basal plane, while the basal-plane dissociated dislocation has to transform into 3-dimension dissociation to glide on the prism plane, both of which produce further resistance to the dislocation glide. There are different kinds of interaction between the edge and screw dislocations, which generate complex defects other than dislocations.
Key words: α-titanium; dislocation; molecular dynamics; dislocation reaction