METHOD FOR ELECTROLYTIC CHROMIUM PLATING Russian patent published in 2021 - IPC C25D3/04 

FIELD: electricity.

SUBSTANCE: invention relates to the field of electroplating and can be used for electrolytic chromium plating of steel parts. The process is conducted while heating at a direct current using an electrolyte solution containing chromium anhydride CrO₃, calcium carbonate CaCO₃ and cobalt sulphate heptahydrate CoSO₄∙7H₂O, wherein chromium plating is conducted at an electrolyte temperature of 18 to 35°C and a current density of 75 to 200 A/dm², and an inorganic additive in the form of nickel sulphate heptahydrate NiSO₄∙7H₂O and hydrofluoric acid HF is additionally included in the composition of the electrolyte, at the following content of electrolyte components, g/l: chromium anhydride CrO₃ 420 to 450; calcium carbonate CaCO₃ 50 to 55; cobalt sulphate heptahydrate CoSO₄∙7H₂O 10; nickel sulphate heptahydrate NiSO₄∙7H₂O 10; hydrofluoric acid HF 0.65 to 0.85.

EFFECT: increase in the chromium deposition rate with the ensured high coating quality, maintained strength characteristics and simultaneous increase in the corrosion resistance and wear resistance.

2 cl, 1 tbl, 1 dwg