The Study of the Effects of VUV/UV Radiation on the Thermal Control Coatings

Abstract

In recent years, extensive research has been conducted on long-term reliability of thermal control coatings (TCC) used in space. The properties of TCC’s directly affect the internal temperature control of spacecraft and their normal performance. In this paper, optical properties of several typical TCC samples including the antistatic silvered cerium glass second reflectance mirror, KS-Z white coating, antistatic F46 film silvered second reflectance mirror were measured in situ in different VUV (115–200 nm) and UV (200–400 nm) ranges and radiation doses using a long-term ultraviolet radiation exposure facility. Data fitting was conducted to obtain the solar absorption ratio degradation curve of the thermal control coatings, and the ratio was extrapolated reasonably. The solar absorption ratio of the thermal control coatings tends stabilize after a certain amount of radiation, whether UV or VUV. Other parameters of the thermal control coatings before and after UV/VUV radiation, such as the surface microstructure and infrared emissivity were also measured and their degradation after UV/VUV radiation is discussed.