无形碳涂层的分子尺度三元学:薄膜厚度,粘附和远程相互作用的影响
G T Gao1, Paul T Mikulski, Judith A Harrison
1Chemistry Department, United States Naval Academy, Annapolis, Maryland 21402, USA.
Journal of the American Chemical Society
|June 13, 2002
概括
使用分子动力学研究了钻石表面之间的原子尺度摩擦. 负载下的三基化学反应减少摩擦,而对面的终结会影响粘附和整体摩擦.
科学领域:
- 部落学 (tribology) 是一个学科.
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 了解原子级摩擦对于设计先进材料和表面至关重要.
- 由于其硬度和低摩擦性能,钻石和碳薄膜被广泛用于 Tribological 应用.
研究的目的:
- 为了研究结钻石和无形碳膜之间的原子级摩擦和磨损.
- 阐明 tribochemical 反应,薄膜厚度和对面和在摩擦中的作用.
主要方法:
- 使用了古典分子动力学模拟.
- 研究了两种无形碳薄膜,厚度各不相同,但sp(3) /sp(2) 比率相似.
- 对面和度是不同的,以评估粘附贡献.
主要成果:
- 在测试负载范围内的两种薄膜厚度中观察到类似的平均摩擦.
- 在临界负载以上, tribochemical 反应诱导膜重组,类似于"run-in",导致摩擦减少.
- 减少对面气终结增加了摩擦,突出了粘附的作用.
结论:
- 三基化学反应和表面重组显著影响原子尺度上的摩擦.
- 对面特性,特别是终结,在调节粘附和摩擦方面发挥着关键作用.
- 这项研究提供了对控制钻石基部落系统摩擦机制的见解.
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