This contribution examines the intricate dynamics of friction and wear in connector design, where the reduction of insertion friction forces while maintaining a low electrical resistance and high mechanical integrity presents a significant challenge.
The undesired disconnection of connectors stands as the primary cause of failure in automotive electrical systems, and with the proliferation of assistance systems and the rising prevalence of electric vehicles, the quantity of connectors increases significantly. Therefore, customizing friction and wear properties in connectors becomes of utmost importance.
Direct laser interference patterning (DLIP) is used to produce asymmetric saw-tooth structures on typical contact materials, aiming to generate an asymmetric tribological behavior. Through careful control of structural inclinations and periodicity, the tailored surfaces exhibit varying degrees of anisotropy, resulting in substantial differences between insertion and removal forces, up to fourfold in certain configurations. It is observed that topographical interlocking is the primary operating mechanism providing the required asymmetry.
Tribological and electrical characterization via simulated insertion/removal cycles highlight improved performance compared to conventional connectors, with marginal impact on electrical properties. The tests are conducted on a self-built multipurpose test rig with varying counter electrode geometry and loads. The wear tracks are evaluated by means of confocal laser scanning microscopy after testing.
The results presented in this contribution provide new insights into the development of connector efficiency in modern electrical systems by deploying a chemistry-free process to tailor the insertion and removal forces in connectors, without affecting the electrical characteristics at their contact spot.