Review on sputtering erosion mechanisms of discharge hollow cathode of ion thruster

The latest progress in the investigation of sputtering erosion mechanisms of discharge hollow cathode of ion thruster was reviewed. The sputtering erosion of discharge hollow cathode has a serious impact on the life and reliability of ion thrusters. Because the kinetic energy of the ions, provided by the low electrostatic potential difference in ion thruster, cannot exceed the sputtering energy threshold of the materials, the mechanisms responsible for the high energy ion sputtering have been a focus in the study of sputtering erosion of discharge cathode. In spite of the extensive theoretical and experimental studies, the issue remains elusive. The major difficulties, problems and possible solutions, as well as the loopholes of the existing theoretical models and experimental simulations, were also tentatively discussed in a thought provoking way.