Preparation method of white aluminum alloy surface thermal control coating with high solar reflectance

TLDR: In this paper, a preparation method of a white aluminum alloy surface thermal control coating with a high solar reflectance is presented, where during the micro-arc oxidation preparation process, a mixture of one or more of sodium silicate, trisodium phosphate, and sodium aluminate, of which the concentration is 2-50 g/L, is adopted as a film-forming agent in the used microarc oxidation electrolyte.

Abstract: The invention discloses a preparation method of a white aluminum alloy surface thermal control coating with a high solar reflectance. The preparation method lies in that during the micro-arc oxidation preparation process, a mixture of one or more of sodium silicate, trisodium phosphate and sodium aluminate, of which the concentration is 2-50 g/L, is adopted as a film-forming agent in the used micro-arc oxidation electrolyte; potassium fluozirconate of which the concentration is 2-30 g/L is adopted as a coloring agent; a mixture of one or more of sodium sulfate, sodium acetate and sodium hypophosphite of which the concentration is 1-15 g/L is adopted as a stabilizer; a mixture of one or more of oxalic acid, cinnamic acid, citric acid and lactic acid is adopted as a PH regulating agent; the PH value of the electrolyte is maintained within the range of 3-6; deionized water is adopted as a solvent; the dosage of all the substances is calculated on the basis of the volume of the added deionized water; the frequency of a pulsed power supply is 50-2000 Hz; the duty ratio is 5-45%; the electric current density is 1-12 A/dm[2]; the reaction time is 20-180 min. The white aluminum alloy surface thermal control coating prepared by adopting the preparation method has a high solar reflectance.