Effect of Magnetic Field on the Current-carrying Friction and Wear Performance of C/Cu Contact Pairs

Carbon / copper (C / Cu) contact pairs have been widely used in pantograph-catenary system of rail transit and motor system of power field. In recent years, the wear of contact pairs is aggravated due to the increase of current-carrying capacity. Some scholars have tried to decouple the multi-physical coupling interaction between interfaces. Among them, the magnetic field has an important influence on the friction and wear performance of the contact pairs, but the influence mechanism is not clear. In this paper, a self-made reciprocating sliding current-carrying friction test bench is used, and permanent magnets are added to simulate the magnetic environment. By changing the magnetic induction intensity, the influence of different magnetic field on the friction coefficient, wear amount and surface topography of contact pairs was studied. The results show that the external magnetic field can effectively reduce the fluctuation of friction coefficient of current-carrying contact pairs. With the increase of magnetic induction intensity, the friction coefficient first decreases slowly and then increases rapidly, while the wear amount decreases continuously. After the introduction of an external magnetic field, the amount of copper transfer on the surface of the strip is significantly reduced. These results are of great significance for ensuring the safe and stable operation of C/Cu contact pairs under electromagnetic environment and guiding the design and manufacture of related structures.