在金属玻璃中压力诱导的稳定放松动态的非单调交叉
Xin Zhang1, Hongbo Lou1, Beatrice Ruta2
1Center for High Pressure Science and Technology Advanced Research, Shanghai 201203, China.
概括
研究人员研究了在压力下的金属玻璃中原子级放松动态. 他们观察到,随着压力增加,原子运动的意外加速与结构变化有关,而不仅仅是密度.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 无形材料的研究研究.
背景情况:
- 了解放松动态对于理解玻璃的形成和特性至关重要.
- 在玻璃中探测原子尺度动力学,特别是在极端条件下,如高压,仍然是一个重大挑战.
研究的目的:
- 为了研究基于的金属玻璃在原子尺度放松动态中的压力诱导的变化.
- 探索放松动态,样本密度,应力和压缩下的局部原子结构之间的关系.
主要方法:
- 开发和应用现场高压同步子高能X射线光子相关谱 (XPCS).
- 利用现场高压同步子X射线衍射来同时分析局部原子结构.
主要成果:
- 在大约3 GPa的放松动态中观察到非单调的压力诱导交叉,原子运动最初减慢,然后在进一步压缩时加速.
- 证明这种异常放松行为与局部原子结构的剧烈变化密切相关,而不仅仅与样本密度或整体应力有关.
结论:
- 这项研究揭示了金属玻璃的稳定放松动态中异常的压力诱导的交叉作用.
- 这些发现突出了当地的原子结构进化的关键作用,在压力下控制放松动态,为玻璃的行为提供了新的见解.
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