Effect of Rotation Speed on the Tribological and Conductive Behaviors of Rolling Current-Carrying Cu Pairs

Abstract

The tribological and conductive performance of the rolling current-carrying pairs were studied at different rotation speeds based on the disc-disc Cu pairs. Whether the current was applied or not, the friction coefficient decreased with the increasing of rotation speed. The average contact resistance increased with the rotation speed and the applied current. The sharp fluctuation of the real-time current was proposed as the failure criterion for the rolling current-carrying pairs, and both the rotation speed and the current accelerated the failure process. Erosion pits and melting could be observed by SEM, and the surface oxidation could be detected by EDS on the failure surface. It was speculated that arc discharge appeared under high speed and large current conditions, which encouraged the transformation of damage mechanism from mechanical wear to arc erosion. These results may provide some useful suggestions on the failure mechanism and life tests of the electro-conductive rotary joints.

The role of relatively humidity in friction and wear behaviors of carbon sliding against copper with electric current

“…Therefore, research on the wear phenomena and wear mechanism of carbon contact strip materials has become one of the important topics in the field of electric railways. Several investigations have been performed that operating conditions such as electric current [4][5][6], velocity [7][8][9][10], vibration [11,12] have an impact on the tribological properties of sliding electric contact materials.…”