Photostability of reflective coatings based on ZrO2 pigments doped by strontium cations

The effect of the doping with SrSiO₃ on optical properties of ZrO₂ powders and their stability at ultraviolet irradiation were investigated. It was founded that the powders doped with 1 mass% of SrSiO₃ possess the greater photostability. Two types of thermal control coatings were fabricated. The first one was based on the undoped ZrO₂ pigment and the second one was based on the ZrO₂ pigment doped by 1 mass% of SrSiO₃. The comparative investigations of their optical properties and photostability show that the coating based on doped pigment is more effective than the coating with undoped pigment. The prediction of optical properties degradation for these coatings was made for the lifetime of 10 years acceding to obtained data. This prediction may be used for altitudes of 600-800 kilometers where the main damaging factor is ultraviolet radiation of the sun.