在金属玻璃成型材料中超均性的方法,表现出脆弱到强的玻璃过渡
Hao Zhang1, Xinyi Wang2, Jiarui Zhang2
1Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada. hao.zhang@ualberta.ca.
The European physical journal. E, Soft matter
|June 28, 2023
概括
金属玻璃 (Al90Sm10) 显示脆弱强 (FS) 玻璃形成,偏离了典型的液体行为. 它的阻塞和粒子定位揭示了与水晶化和玻璃软化相似的关键见解.
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
- 计算材料科学科学 计算材料科学
背景情况:
- 金属玻璃成型 (GF) 液体表现出独特的脆弱-强 (FS) 玻璃成型模式.
- 这些材料偏离了放松时间和扩散的标准现象学关系.
- FS液体在响应函数中显示出真正的热力学特征,并在玻璃过渡温度 (Tg) 上显示出最小的特征.
研究的目的:
- 使用分子动力学模拟研究Al90Sm10金属玻璃中的FS玻璃形成.
- 了解FS GF液体中的异常静态散射和分子干扰.
- 与水和其他FS GF液体中观察到的相似性相关的发现.
主要方法:
- 模拟Al90Sm10金属玻璃的分子动力学.
- 对超均性指数 (H) 的量化,以测量分子干扰.
- 对粒子定位的德拜-沃勒参数 (u2) 的估计.
- 与加热的晶体铜 (Cu) 的比较分析.
主要成果:
- 量化了超均度指数 (H),提供了分子干扰的度量.
- 温度依赖性和H的大小与德拜-沃勒参数 (u2) 一起分析.
- 确定了H ≈ 10-3的临界值,类似于化和玻璃软化Lindemann标准.
结论:
- 这项研究提供了关于FS GF液体,特别是Al90Sm10.10异常行为的见解.
- H的临界值作为玻璃软化和水晶化的指标.
- FS玻璃形成和液体-液体相分离与GF液体中的合作自组装过程有关.
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