在表轴状晶体的塑性放松过程中发生的脱位相互作用
Ilya Svetlizky1, Seongsoo Kim2, David A Weitz2,3,4
1School of Engineering and Applied Sciences (SEAS), Harvard University, Cambridge, MA, USA. isvetlizky@technion.ac.il.
了解晶体可塑性受到观测宏观变形和原子尺度脱位动态的挑战所限制. 这项研究揭示了合晶体中的脱位相互作用如何导致利的塑性松和复杂的3D网络.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 晶体学 晶体学是指结晶学.
背景情况:
- 晶体可塑性对于材料的行为至关重要.
- 同时观察宏观变形和原子尺度脱位动态是具有挑战性的.
- 了解薄膜中应变放松机制至关重要.
研究的目的:
- 研究合晶体中的宏观变形和脱位演变之间的相互作用.
- 阐明尖塑料放松和网络形成背后的机制.
- 了解脱位相互作用在薄膜可塑性中的作用.
主要方法:
- 使用合晶体作为模型系统.
- 采用高速三维 (3D) 共聚焦显微镜进行单粒子成像.
- 解决了实时表轴不适应应变张放松和脱位演变.
主要成果:
- 观察了由位移相互作用驱动的复杂3D位移网络的形成.
- 经过吸引力脱位相互作用的促进,表现出意想不到的尖的塑性松.
- 识别了阻断机制 (静止结,排斥),这些阻断机制分裂了位移网络.
- 发现阻断机制的强度随着晶体膜的厚度而降低.
结论:
- 脱位相互作用关键地控制了薄膜中的塑性变形.
- 吸引力相互作用促进了高效的应变介导失位.
- 这些发现可以从合体到原子尺度进行概括.
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