Effect of silver coating thickness on high current contact stability

A great deal of research related to high current contacts was reported by Holm through the 1960s, but most of this work was carried out using often ingenious analytical methods, before the practicability of computer-based numerical methods. As a result, the analysis does not include the effects of temperature-dependent material properties. We report computations of high current contact stability based on transient nonlinear finite element analysis which includes the effect of temperature-dependent material properties. These analyses indicate that if a Ag coating over Al is too thin and the surface is too rough, the Al can melt under the Ag, without the Ag melting, leading to premature contact instability.