Arc Erosion Wear Characteristics and Mechanisms of Pure Carbon Strip Against Copper Under Arcing Conditions

摘要

The wear behavior of pure carbon strip against copper (carbon/copper pair) under continuous arcing condition was investigated. To simulate the extreme condition of continuous arc discharge at high current, sliding wear tests were conducted on a home-made wear tester. The arc erosion wear characteristics and mechanisms of carbon/copper pair were studied by analyzing the wear scars and wear debris of the carbon strip in detail. Therefore, various analytical techniques, including Raman spectroscopy, transmission and scanning electron microscopy, and focused ion beam systems, were utilized to characterize the wear scars and wear debris of the carbon strip. The results show that the wear rate and the degree of arc erosion of the carbon strip increase with increasing electric current density. Typical entwined turbostratic carbon nanospheres (ETCNs) exhibited sphere-like stacking structure that were observed in the microstructure of the wear debris of the carbon strip produced during the friction process with current, which is the characteristic of the textural changes in carbon materials under combined arcing and sliding friction conditions. Moreover, the number and size of ETCNs increase with the electric current density increase. The arc erosion wear mechanisms of the carbon/copper pair are mainly due to the synergetic action of oxidation ablation, local electric arc impact and high-temperature graphitization under continuous arcing.