On the multi-physics elastoplastic electrical contact of rough surfaces

Abstract

Multi-physics coupling effect and elastoplastic deformation of rough surface asperities on contact interfaces are the two critical factors influencing the electrical contact properties. It is challenging to consider both factors in the modeling and efficient computation of rough surface electrical contact problems. To address this challenge, this study proposes a novel and efficient method for the behavior investigation of multi-physics elastoplastic electrical contact of rough surfaces. The electro-thermal and thermo-mechanical coupling equations are derived by incorporating the Joule heating and resultant expansion of material. The J2 plasticity criterion, with both the isotropic and kinematic hardening laws, describes the plastic deformation of contact components. The displacement field caused by the contact pressure of the asperities is calculated using the boundary integral method, while the stresses due to plastic and thermal strains are treated as bulk stresses, and their contribution is solved using the volume integral method. An iterative algorithm is applied to obtain the electrical contact results including electric potential, electrical contact resistance, temperature rise, contact area, contact pressure, displacement, stress, elastic and plastic strains. This method is validated compared with a finite element model. The influence of plastic deformation and multi-physics coupling on the behavior of rough surface electrical contact is investigated.