Arc erosion characteristics evolution of Ag/Ti₃SiC₂ composites during repetitive arc breakdowns in SF₆ gaseous medium

Abstract

To disclose the impact of SF6 gaseous medium on Ag/Ti3SiC2 contact materials, arc discharges on the Ag/Ti3SiC2 cathodes were performed 100 times in SF6 gas at 10 kV. After 1, 50, and 100 times of arc discharges, the morphologies of arc‐eroded surfaces were characterized. The changes in breakdown strength with the number of tests were recorded. After 100 times of arc erosion, the composition of the surface was characterized, and the morphologies and compositions of the cross section were measured. In the process of multiple arc breakdowns, the arc erosion position randomly changes. In the later stage of tests, the breakdown strength of Ag/Ti3SiC2 increased. The protrusion on the arc‐eroded surface is the ignition point for the arc, the down of protrusion height and the smooth of protrusion tip were observed after multiple arc discharges, which may result in the increase in breakdown strength. After multiple arc erosion tests, Ag2S was detected on the surface by XPS, and part of silicon elements were dissociated outward from Ti3SiC2. The composition change is inferred to be one of the reasons for the rise of breakdown strength.

Influence of nano-mechanical evolution of Ti 3AlC 2 ceramic on the arc erosion resistance of Ag-based composite electrical contact material

“…Compared to traditional Cd-containing and Cd-free reinforcing phases used in electrical contacts, the MAX phase is distinguished by its unique layered structure and the inherent instability of its A atomic layer. Furthermore, at high temperatures, the MAX phase undergoes a "decompositionoxidation" process, which manifests in distinct features such as self-healing, diminished arc energy, and a delay in arc destruction [26,31]. These attributes give it unparalleled advantages in its application to Ag-based electrical contacts.…”

Influence of Electron Beam Treatment on Structure and Phase Composition of TiB2–Ag Coating Deposited by Electrical Explosion Spraying

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