A statistical model of elastic-plastic contact between rough surfaces

作者：Zhao, Guang^*; Li, Sheng-xiang; Xiong, Zhi-liang; Gao, Wen-dong; Han, Qing-kai

来源：Transactions of the Canadian Society for Mechanical Engineering, 2019, 43(1): 38-46.

DOI：10.1139/tcsme-2017-0052

• elastic-plastic contact
• rough surfaces
• asperity
• Hertz contact
• GW model

In a mechanical interface, the contact surface topography has an important influence on the contact stiffness. In the contact processes of asperities, elastic-plastic change can lead to discontinuity and lack of smoothness at a critical contact point. The result is a large difference between the elastic-plastic deformation and the actual asperity deformation. Based on Hertz contact theory, the heights of asperities on a rough surface obey a Gaussian distribution. To take into consideration the continuity of elastic-plastic asperity deformation, we divide the elastic-plastic deformation into three stages: pre-elastic-plastic, mid-elastic-plastic, and post-elastic-plastic deformation. This establishes an elastic-plastic contact model of asperity at a continuous critical point. The contact model of a single asperity fits well with the Kogut-Etsion model and the Zhao-Maietta-Chang model, and the variation trend is consistent. At a lower plastic index, the present model coincides with classical models of contact area and contact load. At a higher plastic index, the simulation results of the present model differ from the Greenwood-Williamson model and the Chang-Etsion-Bogy model but are similar to results from the Kogut-Etsion and Zhao-Maietta-Chang models. This study provides a more accurate microscopic contact model for rough surfaces and a theoretical framework for interface design and analysis.

• 出版日期2019-3
• 单位大连理工大学