Molecular statics was employed to simulate interaction between screw dislocation and twin boundaries(TB)in hexagonal close-packed zirconium.In the moving TB model,the interaction of a moving {10(1―)2} TB with a static 1/3<11(2―)0>{10(1―)0} screw dislocation was investigated.Twinning dislocation(TD)nucleation and movement play an important role in the interaction.The screw dislocation passes through the moving TB and changes to a basal one with a wide core.In the moving dislocation model,a moving 1/3<11(2―)0>{10(1―)0} dislocation passes through the TB,converting into a basal one containing two partial dislocations and an extremely short stacking fault.If the TB changes to the {10(1―)1} one,the moving1/3<11(2―)0>{10(1―)0} prismatic screw dislocation can be absorbed by the static TB and dissociated into two TDs on the TB.Along with the stress-strain relationship,results reveal the complicated mechanisms of interactions between the dislocation and TBs.%采用分子静力学模拟密排六方金属锆中孪晶界与螺位错之间的交互作用.在移动晶界模型中,研究一个移动的{10(1―)2}孪晶界与一个静止的<11(2―)0>螺位错之间的交互作用.在此类交互作用中孪晶位错的形核与移动起到了重要的作用.静止的螺位错穿过了孪晶界并转换为基面上的一个具有宽位错芯的缺陷.在移动位错模型中,一个移动的<11(2―)0>位错穿过孪晶界并转换为两个基面部分位错及它们之间的一段极短的层错.如果在同一个模型中将孪晶界置换为{10(1―)1}类型,这个移动的<11(2―)0>柱面螺位错将被完全吸收并分解为孪晶界上的两个孪晶位错.分析相应的应力-应变曲线与缺陷结构,揭示位错与孪晶界之间的复杂交互作用.
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