Microscopy Study of Fretting Corrosion of Tin Plated Contacts

In recent years, there has been increasing demand to miniaturize wiring harness connectors in automobiles due to the increasing volume of electronic equipment and the reduction of the installation space allocated for the electronic equipment in cars for the comfort of the passengers. In this report, we made fretting test samples of connectors for which contact resistance had increased and analyzed the cross-section of the contact points using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and micro hardness measurement. Based on the observation and measurement results, we considered the change of the contact microstructure for various fretting cycles.