Electrical contacts are essential in many applications including modern transportation means like airplanes, trains and automobiles as well as in everyday electronic portable devices. The mechanical components that form the electrical contact in these applications are always subjected to vibrations and micrometer displacements during use. These vibrations may lead to aggressive fretting wear which in turn affects their durability. Most of the electrical contacts are made of gold which is not a wear resistant material. In order to improve the life-span of such connectors lubricating greases are considered to be a good choice. In this study, special greases were tested to study their influence on improving the life span of automotive electrical connectors. The fretting behaviour was studied using a high frequency fretting tester and a high precision microtribometer. The electrical contacts were tested directly in their original design (male-female coupling) under small amplitude vibrations at a high frequency of 50 Hz thus achieving a real contact simulation. It is shown that dielectric greases do improve the electrical performance of the gold connectors by at least 25 times. The improvement is due to a reduction in wear loss and good isolation of the contact from ambient conditions thus preventing oxidation and third body abrasion. The usage of grease did not significantly affect the frictional aspect of the contact. Greases which can hinder slip between the contacts are beneficial for the endurance of the connector assembly. Results indicate that simulation of electrical contacts by classical crossed-cylinder configuration could yield different results from real simulations thus challenging its credibility.
Investigation of fretting wear and durability of automotive electrical contacts under high frequency vibrations
Untersuchung der Kontaktermüdung und Dauerhaftigkeit der elektrischen Kontakte im Fahrzeug unter Hochfrequenzvibrationen
2008
7 Seiten, 8 Bilder, 2 Tabellen, 10 Quellen
Aufsatz (Konferenz)
Datenträger
Englisch
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|FRETTING AND FRETTING FATIGUE IN METAL-TO-METAL CONTACTS
AIAA | 1970
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