Coupling effect of plastic deformation and surface roughness on friction behaviors of rough line contact for ground metal surfaces

Abstract

Grinding is a pervasive technique employed in manufacturing and machining fields. Metal surfaces after grinding processing exhibit striated surface topography, which can be simplified into a two-dimensional plane strain friction problem, distinct from conventional three-dimensional rough surface friction models. In this paper, a novel approach that integrates dimensional analysis and finite element analysis is proposed to systematically investigate the coupled effect of plastic deformation and surface roughness on the frictional behavior of ground metal surfaces in rough line contact. First, the surface morphology is characterized through experimental surface observation. Subsequently, dimensional analysis was applied to identify the crucial parameters influencing frictional behavior. The actual surface topography was then imported into a numerical model, utilizing the finite element method, to comprehensively investigate the combined effects of plastic deformation and surface roughness on the frictional behavior of ground surfaces. The results show that higher plasticity and a lower local friction coefficient result in earlier sliding initiation. Following the comprehensive onset of sliding across the interface, the steady-state friction coefficient is still influenced by both the local friction coefficient and the degree of plasticity. The friction behaviors are highly sensitive to the interaction between surface roughness and the level of plasticity, and higher plasticity and lower roughness contribute to a reduced friction coefficient. This study contributes to the understanding of the friction behavior of ground metal surfaces, offering insights for the development of novel approaches to reduce friction coefficients.