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纳米尺寸无形金属的尺寸依赖的变形行为表明从集体到个体原子运输的过渡
Naijia Liu1,2, Sungwoo Sohn3,4, Min Young Na5
1Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT, 06511, USA.
Nature communications
|September 26, 2023
概括
无形金属的变形从粘性流向变化到小尺度的界面扩散. 这种由温度和元素扩散度影响的尺寸依赖性行为,为玻璃物理和材料加工提供了新的见解.
科学领域:
- 机械和材料科学 机械和材料科学
- 玻璃物理学 玻璃物理学
背景情况:
- 晶体金属的变形机制已被理解,但无形金属的变形仍然不清楚,特别是在时间和空间尺度上.
- 现有的模型通常假定流动均,未能捕捉小规模的行为.
研究的目的:
- 为了阐明无形金属在小尺度上的变形的原子化机制.
- 为了确定控制变形过渡的关键长度和时间尺度.
- 研究温度和合金成分对变形行为的影响.
主要方法:
- 对无形金属尺寸依赖变形的分析.
- 研究从集体原子运输 (粘性流) 过渡到个人原子运输 (接口扩散).
- 取决于温度的研究,以确定关键的长度尺度,特别是在玻璃过渡期间.
主要成果:
- 无形金属变形在小尺度上偏离同质流动,显示变形速率增加,尺寸减少.
- 观察到变形机制从粘性流向界面扩散的过渡.
- 这种过渡的临界长度尺度取决于温度,在玻璃过渡时达到顶峰.
- 扩散驱动的变形取决于构成,有利于具有更高扩散性的元素.
结论:
- 这项研究揭示了纳米尺度无形金属变形机制的根本性转变.
- 这些发现为纳米力学和无形材料的物理提供了关键的见解.
- 结果可能会为金属玻璃制造提供新的加工技术.
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