▎ 摘　　要

NOVELTY - Production process of nano-passivation coating galvanized sheet involves (i) performing electro-galvanized or hot-dip galvanizing to form a zinc coating on surface of metal substrate, (ii) degreasing the obtained galvanized sheet with alkali, washing with water and drying with hot air, using a chromium-free passivation solution to passivate the surface of the galvanized sheet and form a colorless and transparent passivation layer, and (iii) coating an 8-20 mu m thick nano-passivation coating on the colorless and transparent passivation layer of the galvanized sheet obtained through the treatment by roller coating, and baking, where the chromium-free passivation solution is prepared from water-soluble resin, water-soluble solvent, metal phosphate, phosphoric acid and water, the nano-passivation coating is prepared from aqueous polyester resin, aqueous amino resin, aliphatic dibasic acid ester, nano-filler, colored pigment, silane coupling agent, processing additive and water. USE - The process useful for production of nano-passivation coating galvanized sheet (claimed). ADVANTAGE - The process has simple operation and low production energy consumption. The galvanized sheet obtained by the production has excellent corrosion resistance and wear resistance. DETAILED DESCRIPTION - Production process of nano-passivation coating galvanized sheet involves (i) performing electro-galvanized or hot-dip galvanizing to form a zinc coating on surface of metal substrate, (ii) degreasing the obtained galvanized sheet with alkali, washing with water and drying with hot air, using a chromium-free passivation solution to passivate the surface of the galvanized sheet and form a colorless and transparent passivation layer, and (iii) coating an 8-20 mu m thick nano-passivation coating on the colorless and transparent passivation layer of the galvanized sheet obtained through the treatment by roller coating, and baking at 150-250 degrees C to solid dryness to obtain the product, where the chromium-free passivation solution is prepared from water-soluble resin, water-soluble solvent, metal phosphate, phosphoric acid and water, the amount of the metal phosphate accounted for 3-8 g/100 ml, the amount of the phosphoric acid accounted for 2-3 g/100 ml, the nano-passivation coating is prepared from aqueous polyester resin, aqueous amino resin, aliphatic dibasic acid ester, nano-filler, colored pigment, silane coupling agent, processing additive and water, the nano-filler is formed by mixing nano-graphene powder and nano-silica powder in a mass ratio of 1:(4-5), and the nano-filler accounts for 3-8 wt.%. An INDEPENDENT CLAIM is included for a nano-passivation coating galvanized sheet produced by the above production process, comprising metal substrate, colorless transparent passivation layer coated on the surface of the metal substrate, and nano-passivation coating coated on the surface of the colorless transparent passivation layer.