在深度低温的ZrTi中,快速的晶体生长会融化
Zhihuang Yan1, Feiqi Huang1, Yanxue Wu1
1School of Materials Science and Engineering, Central South University, 410083 Changsha, China.
The Journal of chemical physics
|January 31, 2024
概括
在Zr50Ti50融化的晶体生长速度很快,受液体排序的影响. 一种新的放松机制,包括结构放松和相对子运动,解释了深度低冷液体的快速生长率.
科学领域:
- 材料科学 材料科学 材料科学
- 计算材料科学科学 计算材料科学
- 物理化学 物理化学
背景情况:
- 了解金属融中的晶体生长动力学对于材料加工至关重要.
- 像Zr50Ti50这样的金属合金在不同的条件下表现出复杂的固化行为.
- 现有的理论很难完全解释深度低温时的增长率.
研究的目的:
- 用分子动力学模拟来研究Zr50Ti50融中的晶体生长机制.
- 探索液体排序和动态过程对固化速率的影响.
- 确定控制深度低冷液体中快速晶体生长的新型放松机制.
主要方法:
- 经典的分子动力学模拟.
- 嵌入式原子方法和斯蒂林格-韦伯潜在模型.
- 结晶结方法用于界面诱导的排序分析.
主要成果:
- 模拟显示了快速的固化速率,与过渡状态理论和金兹堡-兰多理论在小低温下一致.
- 预先存在的液体排序 (以体为中心的立方体形状,二面体形状) 影响了晶体生长率.
- 深度低冷却显示出层次放松过程的脱和超冷液体中出现的集体运动.
- 增长动力学是无扩散的,活性障碍较低,与结构放松和相对运动有关.
结论:
- 接口诱导的排序解释了模型的差异,而不是深度低温的温度依赖的增长率.
- 深度低温Zr50Ti50融中的快速晶体生长是由非扩散,放松控制的机制控制的.
- 鉴定的放松机制为金属融中的固化动态提供了新的见解.
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