Numerical Simulations of Asperity Crushing—Application to cold rolling

Abstract

Asperity flattening has a huge influence on friction and wear in metal forming processes. Nevertheless, phenomena that occur at the microscopic scale are still not well understood. Since no experiments can be easily performed in real forming conditions, numerical models are essential to achieve a better knowledge of what happens in these contact regions. In this paper, two finite elements models are presented. The first one represents the flattening of a serrated asperity field in plane strain conditions. The results are compared to the experiments conducted by Sutcliffe [1]. The second one is a tri-dimensional asperity model flattened by a rigid plane. The boundary conditions applied to this model correspond to the ones encountered in a real cold rolling case. The results are compared to the relative contact area computed by a strip rolling model using the analytical laws proposed by Wilson & Sheu [2] and Marsault [3].

Numerical Investigation of the Material Behaviour during Compression Tests for Samples with Rough Surfaces Represented in Different Geometry Scale Factors

“…During strip drawing the significant influence was executed by the drawing speed, so at higher speed values the greater amount of the lubricant escaped from the pockets on the contact surface than at lower speeds. Carretta et al applied an own numerical FE-model regarding the asperity geometry successful for cold rolling process [22]. Karpenko & Akay did numerical computation of the friction force for two contacted rough plates in [23].…”