Investigation of arc spot splitting behavior on aluminum, titanium, and their alloy cathodes under different gas flows

This paper presents an experimental study on the spot splitting behavior of aluminum, titanium, and their alloy cathodes during electric arc discharge. Utilizing high-speed digital cameras, we dynamically captured the splitting motion of cathode arc spots and analyzed their behavior under different pressures of argon, nitrogen, and oxygen. The study also examined the effects of pulsed arc current parameters on spot splitting. We observed a ringlike expansion of pulsed arc spots during splitting, with aluminum cathodes showing better performance than titanium in promoting spot splitting and stabilizing the subsequent motion of the split spots. Oxygen was found to enhance spot splitting more effectively than nitrogen. Furthermore, the parameters of the pulsed arc can control the extent of spot splitting and expansion. These findings provide valuable insights for optimizing arc parameter control in metal film deposition processes.