The deformation behaviour of twinned FCC nanowires has been extensively investigated in recent years. However, the same is not true for their BCC counterparts. Very few studies exist concerning the deformation behaviour of twinned BCC nanowires. In view of this, molecular dynamics (MD) simulations have been performed to understand the deformation mechanisms in twinned BCC Fe nanowires. The twin boundaries (TBs) were oriented parallel to the loading direction [110] and the number of TBs is varied from one to three. MD simulation results indicate that deformation under the compressive loading of twinned BCC Fe nanowires is dominated by a unique de-twinning mechanism involving the migration of a special twin–twin junction. This de-twinning mechanism results in the complete annihilation of pre-existing TBs along with reorientation of the nanowire. Further, it has been observed that the annihilation of pre-existing TBs has occurred through two different mechanisms, one without any resolved shear stress and other with finite and small resolved shear stress. The present study enhances our understanding of de-twinning in BCC nanowires.

中文翻译：

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通过孪生BCC纳米线的解缠可塑性

近年来，对孪晶FCC纳米线的变形行为进行了广泛的研究。但是，对于BCC同行，情况却并非如此。关于孪生BCC纳米线的变形行为的研究很少。鉴于此，已经进行了分子动力学（MD）模拟，以了解双BCC Fe纳米线的变形机理。孪晶边界（TBs）平行于加载方向[110]，并且TBs的数量从一到三不等。MD仿真结果表明，孪生BCC Fe纳米线在压缩载荷下的变形主要由独特的孪生机理决定，该机理涉及特殊的孪生-孪生结的迁移。这种解除缠绕的机制导致了既存结核的完全灭绝以及纳米线的重新定向。此外，已经观察到，预先存在的结核病的灭绝是通过两种不同的机制发生的，一种没有任何解析的切应力，而另一种则具有有限且小的解析切应力。本研究增强了我们对BCC纳米线中的孪生现象的理解。