在La-Ce-Al-Co-Ga散装金属玻璃的热稳定性和β放松之间的相关性
Xiong Shang1, Liang Yang1, Wenkang Tu2
1Center for Advanced Structural Materials, State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China.
The Journal of chemical physics
|August 15, 2025
概括
提高金属玻璃的热稳定性至关重要. 这项研究揭示了β放松过程与热稳定性之间的关键相关性,提供了提高玻璃性能的策略.
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:
- 金属玻璃具有热不稳定性,限制了其应用和加工.
- 提高热稳定性是金属玻璃的关键研究领域.
研究的目的:
- 为了研究β放松与金属玻璃中的热稳定性之间的关系.
- 为了确定β放松参数和热特性 (如玻璃过渡温度和超冷液体区域宽度) 之间的相关性.
主要方法:
- 研究了一个[La0.7Ce0.3) 65Al10Co25]100-xGax模型系统.
- 分析了动态机械性能,以探测放松过程.
- 与热稳定性指标相关联的放松强度,温度和激活能量.
主要成果:
- 在β与α放松强度 (E′′β/E′′α) 和玻璃过渡温度 (Tg) 的比率之间发现了正相关性.
- 在β与α放松温度 (Tβ/Tα) 的比率和超冷液区域宽度 (ΔTx) 之间观察到正相关性.
- 在ΔTx和β放松激活能量 (Eβ) 之间发现了负相关性.
结论:
- 建立了三种关键关系,将β放松动态与金属玻璃的热稳定性联系起来.
- 证明调节β放松是增强热稳定的可行策略.
- 这些发现加深了对控制玻璃稳定性的因素的理解,并为材料设计提供了实际意义.
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