Contact surface condition effect on contact resistance and improving methods

Electrical contact is an important part in electrical switches, the contact resistance of electrical contacts will not only affect the electrical switches properties, but also play an important role in energy saving of electrical appliance. Therefore, electrical contact manufacturers and electrical appliance manufacturers pay more and more attention to the electrical contact resistance. Especially in the relays field, contact resistance is considered as one of the important indicators of relay quality. This paper discusses the commercial electrical contacts surface foreign materials, surface roughness, surface flatness, as well as the surface film formation process and their effects on contact resistance, and puts forward the main technical indicators which affect contact resistance and the improving methods.