A Magnetron Method for Enhancing the Erosion Resistance of Vacuum Interrupter Contacts Using Halbach Arrays

The application of an axial magnetic field (AMF) can promote the rapid transition of a vacuum arc into a diffuse mode, effectively preventing arc constriction. This method is highly effective in mitigating localized overheating and reducing material loss on the contact surface. This paper aims to investigate the effect of Halbach arrays-based AMF on the erosion resistance of contacts under high-current vacuum conditions (4 kA-16 kA). The erosion process of the contacts under the Halbach arrays-based AMF was recorded using a high-speed camera. At the conclusion of the experiment, the microscopic morphology of the contact surface was observed using an electron microscope. The surface was found to be smooth, with no significant ablation pits, and the Cr particles were fine and evenly distributed, demonstrating uniform ablation characteristics. The results indicate that the 80-110 mT AMF generated by the Halbach arrays can significantly enhance the anti-melting resistance of the contacts.