LAUSR

Cathode erosion by ion sputtering is one of the primary erosion mechanisms in hollow cathode discharges. In this paper, the moving mesh approach coupling with a two-dimensional plasma fluid model was employed to simulate the cathode erosion process for 100 h in a hollow cathode arc discharge. In the numerical model, plasma transport, arc flow and heating, and cathode thermal balance were considered. In addition, the electron emission, ion bombardment, and surface radiation were taken into account on the cathode wall. The normal erosion depth on the cathode surface was defined to characterize the degree of cathode erosion. The results showed that the ion sputtering erosion was sensitive to the ion flux toward the cathode wall and the distribution of the plasma potential. The external magnetic field could mitigate the erosion process. The changes of erosion depth and position under different discharge currents, gas flow rates, and intensities of the applied magnetic field were also investigated in this paper.