论文标题
在纳米级处干滑动摩擦的热激活
Thermal Activation of Dry Sliding Friction at The Nano-scale
论文作者
论文摘要
分子动力学（MD）模拟用于研究动力学系数对纳米尺度温度的依赖性。该系统由铝制球形颗粒组成，该铝颗粒由FCC晶格在几层石墨烯层的堆叠上滑动的32000个原子组成，并且使用LAMMPS进行了模拟。相互作用的电势是电荷优化的多体（comb3）电势，而langevin恒温器将系统保持在几乎恒定的温度。假设线性粘性摩擦，$ f_ {fr} = - γv$，在[1，600] k $的$ t \ in [1，600] k $的间隔下得出并在不同温度下得出动力摩擦系数$γ$。结果，通过升高温度，动力学系数降低。因此，尽管将摩擦视为线性粘性模型，但结果与原子尺度摩擦中的热激活相似。也就是说，（1）通过增加滑动速度摩擦力将增加，（2）通过增加温度，动摩擦系数降低。
Molecular dynamic (MD) simulations are applied to investigate the dependency of the kinetic friction coefficient on the temperature at the nano-scale. The system is comprised of an aluminum spherical particle consisting of 32000 atoms in an FCC lattice sliding on a stack of several layers of graphene, and the simulations have done using LAMMPS. The interaction potential is charge-optimized many-body (COMB3) potential and a Langevin thermostat keep the system at a nearly constant temperature. With an assumption of linear viscous friction, $F_{fr}= - γv$, the kinetic friction coefficient $γ$ is derived and plotted at different temperatures in the interval of $T \in [1, 600] K$. As a result, by increasing temperature, the kinetic friction coefficient is decreased. Consequently, while the friction is assumed as a linear viscous model, the results are similar to the thermal activation in atomic-scale friction. That is, (1) by increasing sliding velocity friction force will be increased and (2) by increasing temperature, kinetic friction coefficient decreases.
