Process and product for the corrosion protection treatment of metal surfaces, in particular of steel surfaces

摘要

Process for the corrosion protection treatment of bare metal surfaces, which at least partially represent steel surfaces, wherein the metal surfaces are contacted with an acidic aqueous solution of a fluoro-complex of at least one element M selected from the group B, Si, Ti, Zr and Hf, rinsed with Wasswer and thereafter coated with a cathodic electrodeposition paint, wherein a) the aqueous solution contains not more than 1 mg / l of organic polymer with allylamine or vinylamine monomers, b) the aqueous solution additionally contains at least one further component which is selected from: Nitrate ions, copper ions, silver ions, vanadium or vanadate ions, bismuth ions, magnesium ions, zinc ions, manganese ions, cobalt ions, nickel ions, tin ions, buffer systems for the pH range of 2.5 to 5.5, aromatic carboxylic acids having at least two groups containing donor atoms , Silica particles with a mean particle size below v on 1 μm, and c) the metal surface is not dried before coating with the electrodeposition paint; acid, chromium-free aqueous solution of a fluoro-complex of at least one element M selected from the group B, Si, Ti, Zr and Hf with a pH in the range of 2 to 5.5 for the treatment of metal surfaces, which additionally comprises one or more components selected from: tin ions, bismuth ions, buffer systems for the pH range from 2.5 to 5.5, aromatic carboxylic acids having at least two groups, the ...