Erosion behavior of Ti3AlC2 cathode under atmosphere air arc

We report herein on the arc erosion behavior of Ti3AlC2 cathode under atmosphere at 7 kV d.c. voltage. The arc life and the breakdown strength for Ti3AlC2 are 28.468 ms and 1.239 × 106 V/m, respectively. The process of arc discharging can be divided into three stages: arc formation, steady burning and attenuation, which was observed by a high-speed camera. During steady burning, the arc column is the brightest and the largest. The eroded material was detected by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscope and energy dispersive X-ray spectroscopy. Under the action of arc discharging, the arc erosion morphology characterized with cracks, pores, protrusions with holes displays on the surface of Ti3AlC2. Meanwhile, the material is dissociated and oxidized to TiO, TiO2, Al2O3, arising from the high temperature and energy intensity of electric arc. The different composition and Marangoni effect are responsible for the multiple morphologies.