Numerical Computation of Surface Melting at Imperfect Electrical Contact between Rough Surfaces

This paper presents a surface melting model by means of numerical simulation of three-dimensional imperfect electrical contact (ImPEC) between rough surfaces in a high electrical current application. The continuous convolution and fast Fourier transform (CC-FFT) and discrete convolution and fast Fourier transform (DC-FFT) algorithms with the conjugated gradient method (CGM) for pressure iteration are applied to solve the surface melting problem under thermo-electro- mechanically coupled ImPEC conditions. The computational result suggests that asperity melting by Joule heating of electron tunneling through a surface oxide film layer may be initiated in a very short time interval if the apparent current density is extremely high. Averaged asperity melting speeds at molten contact asperities are also predicted by means of simulated asperity melting heights.