Open AccessStudy on the erosion characteristics of copper‐carbon electrode pairs by DC air arc
Author(s) -
Xie Wenhan,
Wu Guangning,
Yang Zefeng,
She Pengpeng,
Wang Hong,
Zuo Haozi,
Wei Wenfu,
Gao Guoqiang,
Tu Chuanjun
Publication year - 2021
Publication title -
high voltage
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.732
H-Index - 20
ISSN - 2397-7264
DOI - 10.1049/hve2.12124
Subject(s) - anode , cathode , materials science , electrode , carbon arc welding , composite material , electric arc , carbon fibers , copper , plasma arc welding , airflow , metallurgy , electrical engineering , chemistry , mechanical engineering , submerged arc welding , heat affected zone , composite number , engineering , welding
As common electric contact materials, copper‐carbon electrode pairs are widely used in the field of electric contact such as in high‐speed railways, motor collector rings and grounding brushes. They play a key role in energy transmission in the above‐mentioned systems. Arc erosion has become a key issue threatening system safety. In this work, a dedicated arc erosion platform was built to study the polarity effect of copper‐carbon electrode pairs. It was found that arc dynamics and electrodes erosion behaviours were significantly different under different polarities, which could be understood from the mechanism of heat transfer, cooling and electron emission of the electrode. Then, when the carbon material was used as an anode, the arc caused carbon transfer: the carbon material sublimated quickly due to electron condensation and thermal conduction and quickly condensed on the low‐temperature metal electrode, while the carbon material transfer could partly inhibit the oxidation of the cathode metal electrode. In addition, the rapid sublimation of the carbon material produced high‐temperature airflow, which would make the arc impedance fluctuate and cause the arc voltage to jump. Finally, the anode heat transfer and cathode cooling mechanism directly affected the material state, and the erosion of the anode material was more serious.