Influence of breakdown voltages on arc erosion of a Ti3AlC2 cathode in an air atmosphere

摘要

The influence of breakdown voltage on arc erosion of Ti3AlC2 has been investigated. After 3-10 kV arc erosion in air, the cathode surface appeared uneven with pits, cracks and ejected particles. The arc columns were recorded by a high speed camera. By increasing the breakdown voltage, the breakdown current and erosion area increase, meanwhile breakdown strength decreases. Experimental results demonstrated that after high-energy arc erosion in air, Ti3AlC2 was oxidized to TiO2 and Al2O3. Remarkably, crystal transformation from anatase to TiO2 rutile occurred for breakdown voltage higher than 3 kV, the transformation process being completed for breakdown voltage 9 and 10 kV.