在La55Al25Co20金属玻璃中的热力学放松和衰老动态
Adit Sharma1, M V Gorshenkov2, Vladislav Yu Zadorozhnyy2,3
1School of Mechanics, Civil Engineering and Architecture, Northwestern Polytechnical University, Xi'an 710072, China.
The Journal of chemical physics
|October 13, 2025
概括
这项研究揭示了如何影响La55Al25Co20金属玻璃的热力学性能. 增强了动态异质性和放松性,影响了先进应用的热稳定性和老化.
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
背景情况:
- 金属玻璃表现出复杂的热力学行为,受成分的影响.
- 了解原子移动性和结构动力学对于定制材料特性至关重要.
研究的目的:
- 为了研究La55Al25Co20金属玻璃的热力学反应.
- 阐明在动态异质和放松过程中的作用.
主要方法:
- 动态机械分析 (DMA) 是一种
- 不同扫描热量计 (DSC)
- 科尔劳施 - 威廉姆斯 - 瓦茨 (KWW) 压力放松模型
主要成果:
- 确定了一个稳定的超冷液体区域 (ΔT ≈50°C) 和玻璃过渡温度 (Tg) 在220°C开始.
- 观察到突出的,与协同诱导的动态异质性相关的应变敏感β放松.
- 低于Tg的物理衰老通过减少自由体积和β-放松增加了刚性和储存模块.
结论:
- 添加对基于La的金属玻璃的动态异质性,放松性和老化有显著影响.
- 冰形圆形集群有助于放松和几何挫折,影响应力和模量.
- 组合设计可以优化缓,热稳定性和热力学应用的老化.
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