Erosion Evolution and Mass Loss of Polyimide in AO Environment Using 3D Monte Carlo Method

Polyimide films coated on the surface of satellites are exposed to atomic oxygen (AO) environment during service. This will suffer variation of microscopic structure and morphology, leading to corrosion and mass loss in macroscopic. In this work, a 3D undercutting model based on Monte Carlo method (MC) and Ray Tracing method was constructed, with which the AO related erosion feature of polyimide film was evaluated. Then, we predicted the evolution of erosion cross-section of the coated material with defect of different sizes and shapes exposed in higher AO fluence. The macroscopic mass loss was derived by the eroded microscopic volume and material density, during which the actual roughness was considered in our proposed undercutting model. This work provides insights into the study of microscopic 3D erosion morphology and connects with macroscopic mass loss in experiment at higher fluences.