White Anodic Coating on Aluminium Surface for Spacecraft

The white anodic film on aluminium surface is a kind of important thermal control coatings for spacecraft. In this article a systematic study about the film was carried out by anodizing aluminium foil in sulfuric acid electrolyte. The experimental results show that the optical properties of the coating depend strongly upon the film thickness and various operation parameters: polishing time, oxidation voltage, electrolyte temperature etc. Polishing aluminium surface can increase solar reflectance of the coating while increasing oxidation voltage and electrolyte temperature makes infrared emittance rise rapidly. Under the optimized conditions (oxidation voltage 10V, electrolyte temperature 20℃) white anodic thermal control coatings with excellent performance on aluminium surface can be prepared.