A micromechanical model for solving competitive relationship between Joule and frictional heating in sliding electrical contact

Abstract

A micromechanical model is presented to solve the electrical contact problem between a spherical indenter and a homogeneous half-space, accounting for the combined effects of frictional heating and Joule heating. Based on micromechanics theory, the fully coupled multi-physics problem in this work is effectively solved using a sequential electro-thermal-mechanical coupling approach. By applying Fourier integral transforms to the potential functions within Green’s functions and Eshelby’s tensors, explicit frequency-domain solutions for both thermal and elastic fields are derived. A sequential multi-physics coupling algorithm is proposed that integrates the conjugate gradient method with the fast Fourier transform algorithm to ensure efficient and accurate analysis. The model was validated through both finite element simulations and experimental testing. The combined effects of factors such as velocity, load, voltage, current, and indenter radius on frictional heating and Joule heating are thoroughly examined. Additionally, a multiparameter-coupled temperature-rise minimization function model is proposed, which quantitatively characterizes the synergistic effects of load, current, voltage, and indenter radius on the optimal velocity under minimal temperature rise through functional mapping relationships, providing a practical parameterized tool for achieving minimal temperature-rise conditions.