Experimental and Finite Element Analysis of Plastic Domain Evolution of Rough Surfaces during Contact

Abstract

The processing method has an effect on the morphology and yield strength of the rough surface. In this paper, experiments and finite element methods are used to analyze the contact behavior of asperities on the rough surface. And the effects of the distribution, height, surface noise, and yield strength of the asperities on the rough surface on the plastic expansion of the asperities are discussed. For the rough surface of the aluminum alloy machined by the three processing methods, the plastic evolution of the surface asperities is directly observed in the experiment. The results show that when the surface roughness is lower, the plastic growth of various asperities on the surface is more uniform. We consider that the morphology of the asperities consists of the periodic morphology and the noise of this morphology. The plastic deformations of rough surfaces with different morphologies are analyzed by finite element method. The results show that the higher the frequency of the asperity distribution, the smaller the plastic deformation under the same load. And the plastic deformation of asperities increases with height. In addition, the mean value of the noise has a limited effect on the plastic change of the rough surface. However, when the noise variance gradually increases, the plastic area of the asperities shows a slow upward trend.