Damage Study of Copper Alloys Submitted to Vibration Tests

The main requirement for the connector materials used in electrical contacts and submitted to vibration mode is to maintain very low and stable electrical resistance. Wear and fretting corrosion are a major cause of connector failure and the main reasons influencing the reliability of the electrical system. If the use of coating materials in electrical contacts is widespread, the coatings disappear from the contact surfaces after a certain number of vibration cycles and the contact is carried out between the two basic substrates in contact at the interface. Our study relates to the contact resistance characterization under dynamic vibrations for a contact between a sphere and plane using high content copper alloys with no coatings. Only one contact part is subjected to a vibratory movement, the other part is fixed. The contact resistance is continuously measured during the test. An experimental study of contact resistance behaviour is undertaken in order to evaluate the influence of mechanical and electrical material properties on the degradation of conduction. The obtained results show that the hardness and the resistivity of the copper alloys used have a large influence on the component lifespan.