METHOD FOR PROTECTIVE COMPOSITE COATINGS PRODUCTION ON MAGNESIUM ALLOY Russian patent published in 2017 - IPC C25D11/30 

FIELD: chemistry.

SUBSTANCE: method comprises plasma electrolytic oxidation (PEO) of the alloy surface in silicate-fluoride electrolyte in a bipolar mode, in two steps. During the first 200-240 s of alloy surface anodic polarization, process is performed galvanostatically at a current density of 0.5-0.7 A/cm², until the anode voltage reaches 250-270 V, and during cathodic polarization, - potentiostatically at a cathode voltage of -(30-40) V. Then, during 600-700 s, oxidation is continued at an anode voltage, decreasing to 200-210 V, and cathode voltage - to -(8-10) V. A fluoropolymer layer is applied to the formed substrate surface by dipping into a tetrafluoroethylene telomers solution in acetone, followed by coating drying and heat-treating the at 250-275°C for at least one hour. Fluoropolymer coating is repeated 2-3 times.

EFFECT: increased method technology at increased service life and improved corrosion resistance, anti-friction and hydrophobic properties of coatings.

3 cl, 2 dwg, 3 tbl, 4 ex