二元金属玻璃中的原子质量传输:Mg,Al,Ca和Al4的案例研究
1Department of Physics, Maharaja Krishnakumarsinhji Bhavnagar University, Bhavnagar 364001, Gujarat, India.
概括
这项研究揭示了金属玻璃和液体中独特的原子运输机制. 玻璃中的扩散依赖于振动,而液体则使用动态重排,影响玻璃过渡和稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 热力学是一种热力学.
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 非平衡热力学提供了一个框架,将原子运输与可观测量联系起来.
- 了解二元散装金属玻璃 (BMG) 中的质量传输对于材料设计至关重要.
- 之前的工作模拟了无形的Mg2Ca,Al2Ca和Al4Ca系统.
研究的目的:
- 研究二元散装金属玻璃 (BMG) 中的质量运输机制.
- 为了区分在玻璃状和液态中的原子运输行为.
- 为了将玻璃过渡和稳定性与热力学特性相关联.
主要方法:
- 使用来自不可逆热力学的达肯-曼宁 (DM) 方程.
- 在玻璃和液相分析中运用自由体积理论.
- 从分子动力学模拟中获得的输入来量化扩散交叉相关效应.
主要成果:
- 在玻璃 (振动主导) 和液体 (不和性驱动) 阶段确定了不同的质量运输行为.
- 观察到液相表现出非声波振动模式,在玻璃相中减小.
- 发现了玻璃过渡,稳定性,孔形成能量和弹性模块之间的相关性.
结论:
- 金属玻璃中的原子扩散由弹性振动控制,而液体则由动态结构重排驱动.
- 洞理论有效地描述了相位能量,其中波动驱动了液相质量传输.
- 曼宁参数突出了相位转换对间扩散的影响,特别是在随机力下.
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