Arc erosion reduction on electrical contacts using transverse current injection

Electrical contact life time is often directly determined by arc erosion. A method for reducing arc erosion was developed consisting of injecting an additional electrical current flowing parallel to the contact surface. This method was examined in three arc environments using the additional electrical current with a density less than 1 A/mm ²: (1) automobile ignition contacts; (2) pulsed air arc; and (3) low pressure arc in nitrogen. SEM and X-ray examination showed that application of a transverse current in a contact during arcing changed the phase composition and micro structure of the contact surface. Under optimal conditions the micro structure which is formed is significantly more erosion resistant than without the transverse current injection