Electrical Contact Resistance Between Rough Spherical Surfaces: Theory and Simulation

Abstract In practice, most electrical contacts occur on curved surfaces. However, existing studies have primarily focused on predicting the electrical contact resistance (ECR) of nominally flat surfaces. This study develops a theoretical model for the ECR prediction of rough spherical surfaces. First, two simplified contact configurations of rough spherical surfaces are compared, revealing that the configuration involving a rigid spherical surface and a deformable rough surface proves to be more reasonable. Based on this configuration, a theoretical model for ECR prediction is established, incorporating the interaction among contacting asperities, with the rough surface characterized by fractal theory. An iterative approach is employed to solve the contact behavior, including contact force, real contact area, and ECR. The theoretical results show good agreement with finite element simulations. This study provides valuable insights into the electrical contact behavior of rough spherical surfaces, supporting the structural design and failure analysis of electrical contact components in engineering applications.