A rough surface electrical contact model considering the interaction between asperities

Abstract

A rough surface electrical contact model considering the asperity interaction is developed to study the electrical contact behavior. The rough surface is generated by using a two-dimensional Weierstrass-Mandelbrot function. First, the mechanical contact area of the rough surface is determined by the boundary element method in the absence of the electric potential. The electrical contact area is then calculated by a fitting function based on the mechanical contact area. The fitting data is provided by the single-asperity electrical contact model developed in our previous study. By using the electrical contact area of each asperity, the contact force, electrical contact resistance, electric current, and temperature rise on the asperities are calculated. Finally, the electrical contact behavior on the rough surface is thus determined by summarizing the contributions of each contact spot. The finite element simulation of electrical contact of rough surfaces is also conducted to validate the proposed model. The proposed model is used to investigate the effects of the electric potential, fractal surface parameters, and material parameters on the electrical contact behavior. The results illustrate that the developed model can accurately predict the multi-physics behavior of electrical contact.