Deformation twinning, one of the major deformation modes in a crystalline material, has typically been analyzed using generalized planar fault energy ( GPFE) curves. Despite the significance of these curves in understanding the twin nucleation and its effect on the mechanical properties of crystals, their experimental validity is lacking. In this comparative study based on the first-principles calculation, molecular dynamics simulation, and quantitative in-situ tensile testing of Al nanowires inside a transmission electron microscopy system, we present both a theoretical and an experimental approach that enable the measurement of a part of the twin formation energy of the perfect Al crystal. The proposed experimental method is also regarded as an indirect but quantitative means for validating the GPFE theory.

中文翻译：

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评估孪晶形成能的方法：原子模拟与原位 TEM 拉伸试验的比较研究


变形孪晶是晶体材料中的主要变形模式之一，通常使用广义平面断层能 (GPFE) 曲线进行分析。尽管这些曲线对于理解孪晶成核及其对晶体机械性能的影响具有重要意义，但它们的实验有效性缺乏。在这项基于透射电子显微镜系统内铝纳米线的第一性原理计算、分子动力学模拟和定量原位拉伸测试的比较研究中，我们提出了一种理论和实验方法，可以测量一部分完美铝晶体的孪晶形成能。所提出的实验方法也被视为验证 GPFE 理论的间接但定量的手段。