Fretting in copper-to-copper contacts under AC and DC currentconditions

摘要

The effect of fretting on the contact resistance behavior ofcopper-to-copper wire-plate combinations under AC and DC currentcarrying conditions was investigated. The fretting conditions were asfollows: frequency 1 Hz, slip amplitude 100 μm and load 400 g (4N).The current level in both AC and DC conditions was 50 mA. In addition tocontact resistance measurements, SEM and EDX were used to examine thesurface damage in the fretted contact zones. The results indicate thatthe overall contact resistance behavior of copper-to-copper wire-platecouples subjected to the same fretting conditions but under AC and DCcurrents was practically the same. The characteristic feature of thesamples under AC current conditions is a pronounced distortion of thecontact voltage waveforms. The results of SEM surface analysis of thecontact zones indicates that the surface damage resulting from frettingunder AC current conditions was different from that under DC currentconditions