Simulation of Outgassing Breakdown Induced by Electromagnetic Radiation on Metal-Aluminum Film in Atmospheric Environment

Spacecraft operate in complex space environments filled with a variety of natural or anthropogenic particles and fields, which may trigger outgassing breakdown on their surfaces and thus lead to spacecraft failures in orbit. The physical process of outgassing breakdown in the atmosphere is more complex than in vacuum, which requires the consideration of electron-neutral collisions and electron attachment effects in addition to field emission and secondary electron multiplication. In this article, based on particle-in-cell (PIC), a 2-D simulation model of electromagnetically irradiated metal-aluminum film under atmospheric conditions is established to simulate the outgassing breakdown process in oxygen and air, and to analyze the influence laws of gas density, gas composition, microwave field strength, and electron attachment effect on the breakdown. The results show that gas breakdown is related to the background gas composition, and breakdown is more likely to occur in an oxygen environment than in air; the same kind of gas shows different breakdown formation time patterns at low and high pressures. At low pressure, the breakdown time is rapidly shortened with the increase in air pressure, and at high pressure, the breakdown time increases with the increase in air pressure; the electron attachment has an inhibitory effect on the gas breakdown at high air pressure.