An investigation of the contact behavior of electric distributed filament contacts

The findings of a preliminary experimental investigation into the contact behavior of nonmetallic, distributed filament contacts (DFC´s) are reported. The study was designed to probe the effects of numerous fibrous micro-contacts upon the electro-mechanical behaviors of composite contacts and to compare the resultant behaviors with conventional metal contacts. Four composite materials, representing the variables of interest to this study, were processed into electrical contacts by two novel manufacturing methods. Static and dynamic tests reveal that DFC contact resistances can saturate at a level of as low as 10 g, and that DFC contact stability is, similar to that of metals, dependent upon the contact loads and the contact surface hardness, but nearly independent of the properties of the carbon fibers. The results suggest that it is possible to tailor DFC electro-mechanical characteristics over a range that is not possible with monolithic contact materials by the judicious selection of matrix resin, fiber loading, and surface microstructures.