机械放松和平衡动力学之间的联系在高的金属玻璃中
Y J Duan1,2, M Nabahat2, Yu Tong3
1School of Mechanics, Civil Engineering and Architecture, Northwestern Polytechnical University, Xi'an 710072, China.
Physical review letters
|February 16, 2024
概括
这项研究表明,高金属玻璃中的结构放松涉及到广泛的激活能量,而不仅仅是β放松. 压力放松与平衡率相关,显示微观结构的减少和动态异质性的增加.
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
- 物理化学 物理化学
背景情况:
- 金属玻璃在从非平衡状态过渡到超冷液体时表现出复杂的放松现象.
- 了解结构放松的动力学对于预测材料特性和稳定性至关重要.
研究的目的:
- 为了研究机械放松和平衡动力学在特定高金属玻璃 (Pd$_{20}$Pt$_{20}$Cu$_{20}$Ni$_{20}$P$_{20}$) 之间的相关性.
- 阐明结构放松的基本机制及其激活能量的分布.
主要方法:
- 在金属玻璃中,详细分析了压力放松在老化时间上的演变.
- 压力放松时间与平衡率的相关性.
- 在放松过程中对微观结构和动态异质性变化的评估.
主要成果:
- 结构性放松的特点是激活能量的广泛分布,超出通常接受的β放松范围.
- 在压力放松时间和平衡速度之间观察到明显的相关性.
- 发现微观结构异质性的下降与动态异质性的增加一致.
结论:
- 这些发现挑战了对金属玻璃中放松过程的传统观点.
- 这项研究为放松动力学和热力学之间的复杂相互作用提供了新的见解.
- 这项工作增强了对高金属玻璃老化和寻求平衡行为的理解.
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