在金属玻璃中原子层次的碎片透
David Z Chen1, Crystal Y Shi2, Qi An3
1Division of Engineering and Applied Sciences, California Institute of Technology, Pasadena, CA 91125, USA. dzchen@caltech.edu.
概括
金属玻璃表现出异国情调的特性, 碎形结构由透集群解释. 原子在液相中透,在玻璃过渡温度变硬,揭示了一个新的组织机制.
科学领域:
- 材料科学
- 凝聚物质物理学
- 计算材料科学
背景情况:
- 金属玻璃具有独特的特性, 归因于它们的原子层结构.
- 这些非晶体结构的基本物理机制,特别是碎形方面,仍然不太清楚.
研究的目的:
- 在金属玻璃中阐明结构组织机制.
- 确定短距离的分形和长距离的同质结构之间的关系.
- 验证金属玻璃结构的透集群模型.
主要方法:
- 在现场X射线衍射
- 进行X光断层扫描
- 分子动力学模拟
主要成果:
- 从分形到同质组织的结构交叉证明范围越来越大.
- 识别了透集群作为一个模型,解释了各种金属玻璃组合的结构细节.
- 在液态阶段的原子透与玻璃过渡温度的结构刚性相关.
结论:
- 透集群模型为金属玻璃中的原子组织提供了物理机制.
- 液态中的原子透是导致金属玻璃冷却后刚性结构的关键因素.
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