Black ceramic thermal control coating prepared by microarc oxidation

The black thermal control coating was produced by in situ growth on an aluminum alloy by a relatively new method: microarc oxidation (MAO). In this article, the black MAO thermal control coating that had a high solar absorptance and a high infrared emittance was produced in a 0.1 mol/L NaAlO₂ electrolyte system. The optical properties and phase composition of the coating across the surface to the substrate-coating interface were studied by a spectrophotometer and X-ray diffraction. Experimental results show that the MAO coating can reach a solar absorptance value > 0.90 and an infrared emittance value >0.77.