METHOD FOR PRODUCING SUPERHYDROPHOBIC COATINGS ON MAGNESIUM-CONTAINING ALUMINUM ALLOYS Russian patent published in 2021 - IPC C25D11/04 

FIELD: electroplating.

SUBSTANCE: invention relates to the field of electroplating, it can be used in the formation of coatings that provide protection from moisture and reduction of the rate of corrosion processes during the operation of constructions and structures made of aluminum alloys doped with magnesium in an atmosphere with high humidity and prevent their icing in winter. The method includes plasma-electrolytic oxidation (hereinafter – PEO) of the product with its anode polarization in an electrolyte containing, g/l: potassium tartrate C₄H₄O₆K₂·0,5H₂O 10-30 and sodium fluoride NaF 0.6-2.0, in a galvanostatic mode at an anode current density of 150-160 A/dm², and an increase in the anode voltage from 10-30 to 330-340 V for 1.5-3.0 minutes. During the first minute, the voltage is increased until micro-discharges occur on the oxidized surface. The PEO-coated product is kept in a drying box at a temperature of 250-280ºC for 1-3 minutes. Immediately after that, it is immersed for 1-2 minutes in the melt of ultrafine polytetrafluoroethylene at a temperature of 310-330ºC at the boundary of its transition to a solid state. The product removed from the melt is dried at a temperature of 250-280ºC and during 1.5-2.0 hours the temperature is reduced to room temperature.

EFFECT: simplification of the method and its hardware design, reduced labor and electricity consumption for its implementation and a reduced cost of the coatings produced while ensuring their high protective qualities.

2 cl, 4 ex, 2 dwg