ANTICORROSIVE COATING APPLICATION METHOD Russian patent published in 2020 - IPC C25D5/10 C25D5/50 

FIELD: electroplating.

SUBSTANCE: invention relates to electroplating and can be used for application of protective galvanic coatings with subsequent thermal treatment. Proposed method comprises de-fatting of part, etching part and subsequent deposition of layers of zinc-tin-zinc-tin system with subsequent thermal treatment of steel. Between the tin and zinc layers, an intermediate layer of copper with thickness of 1 mcm is applied by an electrochemical method. Heat treatment of the part is carried out at temperature of 100 to 180 °C for 1 to 12 hours. Copper layer is applied from the non-toxic pyrophosphate electrolyte in a two-step mode at current density of 3 A/dm² for 30 seconds, and then at current density of 0.7 A/dm² for 190 seconds.

EFFECT: technical result is the development of a method of applying coating on parts of low-alloyed carbon steels with accurate tolerances and / or having thread, having in conditions of accelerated corrosion tests coatings of more than 8000 h and during operation of parts in all climatic conditions high protective properties due to prevention of mutual diffusion of layers of zinc and tin, which are part of coating.

1 cl, 1 dwg, 1 ex