Preparation and Space Environmental Stability of a Nano-Materials Modified Thermal Control Coating

Abstract

As an essential part of the spacecraft thermal control system, thermal control coatings are widely used. In this paper, nanometer modification technology for spacecraft thermal control coatings is studied. Sol-Gel technology is used to add nano-SiO2 into thermal control coating system, where TEOS is used as the precursor of SiO2, in order to modify the binder and the filler of the coating system. The thermal control coatings were characterized by FTIR, PL and optical properties testing, both before and after proton irradiation, which has a significant applied background in engineering and theoretical research importance. The test results prove that the nano modified coating has well established optical properties (αs ≤ 0.2) and radiation stability. After 90 keV proton irradiation, Δαs of the nano modified coating is reduced to 0.12. The stability improves almost 50 % as compared to ordinary ZnO white paint. The main reason why the performance of nano modified coating degrades is that defects are formed in ZnO during the irradiation, according to the analysis. Modified ZnO powder can effectively eliminate the variations and quantities of irradiation defects, such as oxygen vacancies. This not only improves the proton irradiation stability of ZnO powder, but also effectively reduces the absorbed oxygen content in the coating system, thereby, lowering the damage to chemical bonds in the adhesives.