Correlation between fretting situation and the contact resistivity of electrical connections

Nowadays one of the most dynamically progressing production sector is the car industry. All units of every vehicle are developed uninterrupted. Since the electronics are the most progressive and sensible parts of cars, so the reliable power supply and the contact quality became a more and more important parameter. According to a new trend, which is beginning nowadays, a car has to be made in such a way that all of the components are used up at the same time, so that the service-costs could be avoided. Today incandescent bodies are planned in such a way that during the lifetime of an average car they can work efficiently and with excellent light-radiation without exchange (10-15 years). To utilize these advantages it is necessary to apply such contacts, which are also able to resist against similar long time the aggressive vibrations during the usage of the car. Besides the long-life bulbs further electrical instruments of the vehicles also need reliable contacts with unchanged electrical properties during a long-life duration. This paper reports experimental results on an investigation project simulating electrical connection behaviour of moving vehicles. Certain possibilities to avoid typical contact failures are also shown. The alloy used for the experimental series was bronze (copper and 5 wt. % tin) for both partners.