取决于温度的摩擦诱导的表面无形化机制的水晶
Jie Qin1, Yilong Jiang1, Shehui Dang1
1Tribology Research Institute, Key Laboratory of Advanced Technology of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China.
Langmuir : the ACS journal of surfaces and colloids
|September 1, 2023
概括
温度上升会抑制的无形化,这是由于相互竞争的热激活和剪切应力效应造成的. 再结晶是一种热激活的过程,随着温度的增加而增加,成为减少整体无形化的主要因素.
科学领域:
- 材料科学 材料科学 材料科学
- 部落学 (tribology) 是一个学科.
- 计算物理 计算物理
背景情况:
- 中的摩擦诱导的表面无形化是设备磨损和可靠性的关键因素.
- 对无形化机制和温度效应的实验研究是具有挑战性的,因为观察晶体-无形界面动态很困难.
研究的目的:
- 通过反应分子动力学模拟,阐明形态化的温度依赖及其潜在机制.
- 研究不同温度下的无形化和再结晶过程之间的相互作用.
主要方法:
- 反应分子动力学 (MD) 模拟被用于模拟的摩擦诱导的表面无形化.
- 开发了分析模型来描述观察到的无形化和再结晶动力学.
主要成果:
- 发现较高的温度抑制了整体无形化的程度,与最初的假设相反.
- 无形化由两个相互竞争的热激活过程控制:剪切驱动的无形化和再结晶.
- 形态化速率表现出类似谷的温度依赖性,这是由于热激活和剪切应力减轻之间的平衡.
- 再结晶率随着温度的增加而单调地增加,成为高温下减少无形化的主要原因.
结论:
- 重结晶在较高温度下显著抵消无形化,解释了观察到的抑制.
- 开发的分析模型提供了一个定量框架,用于理解在摩擦下的温度依赖相变.
- 这些发现为提高基于的设备的可靠性和性能提供了关键的见解.
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