Kim Hong-Kyu, Kim Sung-Hoon, Ahn Jae-Pyoung
Advanced Analysis Center, Korea Institute of Science and Technology, Seoul, 136-791, Republic of Korea.
Mechanical R&D Group, Samsung Electronics, Gyeonggi-do, 16677, Republic of Korea.
Appl Microsc. 2020 Sep 17;50(1):19. doi: 10.1186/s42649-020-00039-2.
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.
形变孪晶是晶体材料中的主要形变模式之一，通常使用广义平面层错能（GPFE）曲线进行分析。尽管这些曲线对于理解孪晶形核及其对晶体力学性能的影响具有重要意义，但其实验有效性仍存在不足。在这项基于第一性原理计算、分子动力学模拟以及透射电子显微镜系统内铝纳米线定量原位拉伸测试的对比研究中，我们提出了一种理论和实验方法，能够测量完美铝晶体孪晶形成能的一部分。所提出的实验方法也被视为验证GPFE理论的一种间接但定量的手段。
