纳米Fe/Ni薄膜界面位错的形核和发射

The Nucleation and Emission of Dislocation of Nano Fe/Ni Interface

用分子动力学模拟的方法研究了拉伸加载下位错在Fe/Ni界面的形核和发射过程。拉伸沿Fe[1 0 0]方向进行,平行于界面。由于晶格失配,系统弛豫后在Fe(0 0 1)/Ni(1 1 0)界面处会形成长方形的失配位错网络。模拟结果显示,当应变达到7.2%时,滑移位错首先在界面处失配位错线上形核,随着应变增加滑移位错向铁内部发射,而在镍内部并没有位错发射。当应变达到8.4%时,镍内才出现位错发射。在Fe基底中位错主要在{1 1 0}滑移面上滑移,而在Ni中主要在{1 1 1}滑移面上滑移。

Molecular dynamics simulations were carried out to investigate the nucleation and emission of dislocation initialized from an interface within a Fe/Ni bilayer. A tensile loading was applied parallel to the issued interface. After relaxation, rectangular shaped dislocations were observed at the Fe(0 0 1)/Ni(1 1 0) interface. The simulation results show that glide dislocation nucleated from the interface firstly when the strain reach 7.2%, and emitted into Fe layer as the strain increasing. The dislocation nucleated and emitted in Ni layer only when the strain reached 8.4%. Glide dislo- cations were found to mainly occur on {1 0 1} plane in Fe layer and on {1 1 1} plane in Ni layer.