Influence of interface oxidation on the electrical contact properties of C-Cu contact pairs

Pantograph catenary system is the only way of train energy transfer and is a typical carbon/metal contact pair. Due to its long-term operation in the atmospheric environment, metal oxide film will be formed on the surface of the pair. The highresistivity of oxide film will affect the stability of electric energy transmission and bring severe challenges to the safe operation of current carrying friction pairs. This paper presents a method to simulate different oxidation states by quantitatively controlling the thickness of oxide film on the surface of carbon sliding plate, and studies the effect of interface oxidation on the electrical contact performance of current carrying friction pair. The results show that the contact resistance first decreases and then increases with the increase of oxide film thickness, The change of current carrying efficiency is just the opposite; The arc discharge energy and duration first decreased and then increased with the increase of oxide film thickness. The research content has certain significance for improving current carrying tribology and ensuring the safe and stable operation of C/Cu contact pair.