Zhu Shengguang, Ni Liyong
University of Electronic Science and Technology of China, Zhongshan Institute, Zhongshan 528402, China.
College of Mechanical Engineering, South China University of Technology, Guangzhou 510641, China.
Micromachines (Basel). 2021 Nov 21;12(11):1428. doi: 10.3390/mi12111428.
Previous research on friction calculation models has mainly focused on static friction, whereas sliding friction calculation models are rarely reported. In this paper, a novel sliding friction model for realizing a dry spherical flat contact with a roughness effect at the micro/nano scale is proposed. This model yields the sliding friction by the change in the periodic substrate potential, adopts the basic assumptions of the Greenwood-Williamson random contact model about asperities, and assumes that the contact area between a rigid sphere and a nominal rough flat satisfies the condition of interfacial friction. It subsequently employs a statistical method to determine the total sliding friction force, and finally, the feasibility of this model presented is verified by atomic force microscopy friction experiments. The comparison results show that the deviations of the sliding friction force and coefficient between the theoretical calculated values and the experimental values are in a relatively acceptable range for the samples with a small plasticity index (Ψ≤1).
以往对摩擦计算模型的研究主要集中在静摩擦方面，而滑动摩擦计算模型的报道较少。本文提出了一种新颖的滑动摩擦模型，用于实现微/纳尺度下具有粗糙度效应的干式球-平面接触。该模型通过周期性基底势的变化产生滑动摩擦，采用了格林伍德-威廉姆森随机接触模型关于粗糙峰的基本假设，并假设刚性球体与名义粗糙平面之间的接触面积满足界面摩擦条件。随后采用统计方法确定总滑动摩擦力，最后通过原子力显微镜摩擦实验验证了所提出模型的可行性。比较结果表明，对于塑性指数较小（Ψ≤1）的样品，滑动摩擦力和系数的理论计算值与实验值之间的偏差处于相对可接受的范围内。
