Development of a Database on the Changes in the Optical Properties of Materials used on the External Surfaces of Spacecraft Under the Action of the Space Environment Factors

摘要

Currently, there exist a large number of studies in the stability of the optical properties of materials used on the external surfaces (blankets, thermal control coatings, solar arrays etc.) of spacecraft. All of them, confirm the fact that the factors of the space environment (FSE) exercise a strong influence both on the spectral and the integral optical parameters of the materials. The purpose of the project was a development of the Database (DB) in the electron format DBMS Access2000, including results of investigation of optical properties of external materials for space vehicles (SV) under conditions of SEF. Within the framework of the present project, laboratory testing for materials applied to external surfaces of SV were carried out under the action of UV-radiation, electrons having an energy of 40, 100 and 200 keV, and also protons having an energy of 40, 150, 300 and 500 keV. Testing was performed for the case of separate action of each of the factors mentioned on the material. The maximum level of an exposure dose, which was reached while performing laboratory testing, amounted up to 1 equivalent solar year under conditions of GEO for the UV-radiation. The objects to be investigated were thermal control coatings (8 trade marks), fabrics (6 trade marks), polymeric films (3 trade marks), solar array elements (6 trade marks). The main material characteristics for materials were: integral and spectral coefficients of electromagnetic radiation absorption, reflection and transmission, coefficient of thermal radiation, angular dependency for reflected and transmitted electromagnetic radiation within the plane of beam incidence. The characteristics mentioned were measured before and after a radiation action, and also in the course of radiation action for different values of the dose absorbed. The total volume of the Data Base amounted up to approximately 2600 records, as represented in tabular and graphical form.