Preparation of Ni–P alloys super-black materials applied to baffle surface

Super-black materials refer to the materials whose reflectivity is less than 0.5% and have many significant applications in the aerospace field. Though super-black materials have excellent optical properties, most of them cannot be directly applied to the baffle of star trackers because of all kinds of limits. We presented a method to improve the preparation of super-black materials based on Ni–P alloys which helped this material better applied to star tracker baffle. This process chose the concentration of 10% oxalic acid solution to activate the aluminium surface and enlarged the plating area of Ni–P alloys film. Meanwhile, we anodised Ni–P alloys film in the non-oxidising acid solution instead of conventional blackening process. Consequently, the method improved the controllability of blackening process and avoided the time error. Thus, this method of preparing super-black materials could be applied to star tracker baffle.