METHOD FOR PRODUCING CORROSION-RESISTANT HYBRID COATINGS ON MAGNESIUM AND ITS ALLOYS Russian patent published in 2023 - IPC C25D11/30 

FIELD: corrosion-resistant coatings.

SUBSTANCE: formation of corrosion-resistant hybrid coatings on magnesium and its alloys, applied in various fields of industry: mechanical engineering, aircraft and automotive manufacturing, instrument making, computer, space and defense technology, as well as implant surgery. The method involves plasma electrolytic oxidation of magnesium or its alloy in an aqueous electrolyte containing, g/l: sodium silicate 20-25 and sodium fluoride 4-7, in a two-stage bipolar mode, at the first stage of which the anodic voltage component is changed potentiodynamically, the cathodic component is maintained potentiostatically, at the second stage, the anodic and cathodic components are changed potentiodynamically with the formation of a base ceramic-like PEO coating with a porous surface layer. The formed base PEO coating is processed in one stage in a solution containing 0.05-0.10 M benzotriazole and 50-60 g/l polycaprolactone in dichloromethane, preferably using a vacuum impregnation apparatus, and dried.

EFFECT: increase in the corrosion resistance of protective coatings obtained on the surface of magnesium and its alloys, an increase in their service life when operating in corrosive environments due to the formation of the self-healing function of the coatings.

2 cl, 3 dwg, 2 tbl