Hydrogen atmosphere can significantly change the tribological behavior at diamond and diamondlike carbon (DLC) surfaces and the friction-reducing effect depends on the partial pressure of hydrogen. We combined density functional theory modeling and thermodynamic quantities to predict the equilibrium partial pressures of hydrogen at temperature T, P-H2 (T), for a fully atomic hydrogen passivated diamond surface. Above the equilibrium P-H2 (T), ultralow friction can be achieved at diamond and DLC surfaces. The calculation agrees well with friction tests at various testing conditions. We also show that P-H2 (T) increases with temperature; therefore, the temperature effect observed in friction tests should first be treated as an equilibrium factor rather than a kinetic factor. (C) 2008 American Institute of Physics.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据