Effect of Contact Parameters on Current Density Distribution in a Contact Interface

The distribution of individual current paths within a smooth mated surface contact interface results in the areas of highest current density being located at the outer rim of the contact interface. As contact surface roughness increases, the areas of highest current density become more evenly distributed across the contact interface, though still biased toward the outer rim. This effect can be predicted using a 3-dimensional simulation visualization technique and validated experimentally. The technique used for experimental validation involves using thermal camera technology to directly view the thermal response of the material within a contact interface. This is done as a volt-age/current pulse is applied across a plated electrical contact surface mated to an appropriate probe surface. These results are then used to visualize the resulting effect on the current density distribution. This work focuses on the further development and application of the simulation tool and thermal observation tech-nique to be able to better quantify contact interface thermal per-formance with respect to multiple contact parameters.