Investigation Of Space Combined Environment Degradation Effect On Spacecraft Thermal Control Coatings

A Combined environment which consists of charged particle radiation and ultraviolet(UV) radiation exists in the medium and high Earth orbit. It results in great degradation of the properities of spacecraft surface materials such as the solar absorptance increase of thermal control coatings, mechanical properties damage of thin films, et al. This becomes a major adverse factor in the devolepment of long-life and high reliability spacecrafts.This thesis bagan with the review of space combined environment effect investigation. The dose-depth profile of charged particle in the materials was calculated, and a fitting method of space environment dose-depth profile was used for the determination of test parameters. Then five types of thermal control coatings were exposed to low energy proton, low energy electron and UV individually or simultaneously in a low energy combined environment test facility. The fluence of electron and proton is equal to 15-year total dose of GEO. The total fluence of UV is 5000ESH. In the test in-situ solar absorptance measurement was conducted. The degradation law of solar absorptance and spectral reflectance of materials was analysed. A fitting calculation of solar absorptance was performed and the method of life prediction of thermal control coatings in the combined environment was discussed preliminarily.