Investigation on arc erosion characteristics of Ag/Ti3SiC2 composites in SF6 mixed with buffer gases

Electrical contact materials are core components in the gas sealing devices. In an airtight chamber, the arc erosion behaviors of Ag/Ti3SiC2 composites in SF6/N2 and SF6/CO2 were studied. The sample surfaces were observed by TFESEM and 3D LSCM, the phase constituents of the eroded surfaces were revealed by XPS, and the arc discharge frames in SF6 mixtures were observed by a high-speed video camera. With the growing of buffer gases in SF6 mixtures, the breakdown strength decrease, while the erosion area and the arc energy increase. In the two types of SF6 mixtures, the erosion centers are rough and cracks appear on the erosion edges. Seriously in SF6/CO2, oxides and dense pores exist in the erosion regions of Ag/Ti3SiC2 composites. Based on the experimental results, the arc erosion mechanisms of Ag/Ti3SiC2 in SF6 mixtures are proposed.