PRE-TREATMENT COMPOSITION Russian patent published in 2021 - IPC C23C22/50 C23C22/53 C23C22/56 C23C22/57 C23C22/78 C23C22/83 

FIELD: metallurgy.

SUBSTANCE: group of inventions relates to a system of compositions for treatment of a metal substrate, a method for treatment of a metal substrate and variants of treated substrates. The system of compositions for treatment of a metal substrate comprises a first composition for contacting at least a part of the substrate surface, containing a cation of a lanthanide family element and an oxidising agent, and a second composition for contacting at least a part of the substrate surface, containing a Group IA metal carbonate and substantially free of an oxidising agent and fluoride, or a third composition for contacting at least part of the substrate surface, containing a cation of a IVB group metal.

EFFECT: inventions allow to provide treated metal substrates with corrosion resistance and adhesion properties equivalent to or even superior to the corrosion resistance and adhesion properties provided by means of using phosphate or chromium-containing conversion coatings.

24 cl, 2 dwg, 13 tbl, 6 ex