中国有色金属学报(英文版)
中國有色金屬學報(英文版)
중국유색금속학보(영문판)
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
2015年
8期
2666-2674
,共9页
运动行为%刃型位错%氦%原子模拟%镍
運動行為%刃型位錯%氦%原子模擬%鎳
운동행위%인형위착%양%원자모의%얼
movement%edge dislocation%He%atomic simulation%Ni
应用分子动力学(MD)技术和改进分析型嵌入原子法(MAEAM)研究氦原子对镍金属中(a/2)?110?{111}刃型位错迁移行为的影响。首先通过计算晶格的Burgers矢量分布,确定两刃型分位错之间的平衡距离(Ded)约为25.95?,而它们之间的堆垛层错能(Esf)约为108 mJ/m2。然后研究He原子在晶格中不同位置的形成能(Ef),发现He原子在镍金属晶体的张力区域受到晶格的吸引,而其在压缩区域则受到晶格排斥。通过探讨 He 原子与刃型位错之间的相互作用发现,相比于置换He原子而言,间隙He原子对位错迁移行为的影响更强烈。最后,研究表明间隙He原子的迁移在第一个分位错跨过后表现更明显,同时刃型位错也为He原子迁移提供了更快速的扩散路径。
應用分子動力學(MD)技術和改進分析型嵌入原子法(MAEAM)研究氦原子對鎳金屬中(a/2)?110?{111}刃型位錯遷移行為的影響。首先通過計算晶格的Burgers矢量分佈,確定兩刃型分位錯之間的平衡距離(Ded)約為25.95?,而它們之間的堆垛層錯能(Esf)約為108 mJ/m2。然後研究He原子在晶格中不同位置的形成能(Ef),髮現He原子在鎳金屬晶體的張力區域受到晶格的吸引,而其在壓縮區域則受到晶格排斥。通過探討 He 原子與刃型位錯之間的相互作用髮現,相比于置換He原子而言,間隙He原子對位錯遷移行為的影響更彊烈。最後,研究錶明間隙He原子的遷移在第一箇分位錯跨過後錶現更明顯,同時刃型位錯也為He原子遷移提供瞭更快速的擴散路徑。
응용분자동역학(MD)기술화개진분석형감입원자법(MAEAM)연구양원자대얼금속중(a/2)?110?{111}인형위착천이행위적영향。수선통과계산정격적Burgers시량분포,학정량인형분위착지간적평형거리(Ded)약위25.95?,이타문지간적퇴타층착능(Esf)약위108 mJ/m2。연후연구He원자재정격중불동위치적형성능(Ef),발현He원자재얼금속정체적장력구역수도정격적흡인,이기재압축구역칙수도정격배척。통과탐토 He 원자여인형위착지간적상호작용발현,상비우치환He원자이언,간극He원자대위착천이행위적영향경강렬。최후,연구표명간극He원자적천이재제일개분위착과과후표현경명현,동시인형위착야위He원자천이제공료경쾌속적확산로경。
The molecular dynamics (MD) simulation and the modified analytical embedded-atom method (MAEAM) were used to study the influence of a He atom on the movement of the(a/2)?110?{111} edge dislocation in Ni. First, the calculated Burgers vector distribution shows that the equilibrium dissociation distance (Ded) and the stacking fault energy (Esf) between two partial edge dislocations are about 25.95 ? and 108 mJ/m2, respectively. Then, the obtained formation energies (Ef) of a He atom at some different sites demonstrate that the He atom is attracted and repelled in the tension and compression regions, respectively. And the He?dislocation interaction reveals that an interstitial He atom plays a more significant role in the dislocation movement than a substitutional He atom. Finally, it is found that the movement of an interstitial He atom is apparent as the first partial dislocation bypasses and the edge dislocation offers fast-diffusion path for the migration of a He atom.