METHOD OF PASSIVATION OF STRIP-SHAPED BLACK PLATE Russian patent published in 2018 - IPC C23C22/05 C23C22/34 C23C22/78 C23C22/82 C23G1/00 C25F1/06 

FIELD: metallurgy.

SUBSTANCE: invention relates to the passivation of strip-shaped black plate. Method includes passing a strip of cold-rolled, hardened and rolled black plate with a carbon content of 20 to 1000 million^-1 by weight through a coating machine for strip steel with a strip speed of at least 200 m/min, cleaning and degreasing said strip in an alkaline solution of sodium hydroxide or potassium hydroxide and washing it, electrochemical treatment of the strip in an alkaline electrolyte at a current density of 2 to 30 A/dm² with a steel strip connected as an anode, washing it and drying it, application of an aqueous chromium-free solution to form a conversion layer on the surface of the strip and a bonding layer for paints and organic coating materials. Solution used contains the following components: a) titanium and zirconium, or b) titanium, zirconium and manganese, or c) titanium, zinc and phosphates, or d) titanium, zinc, manganese and phosphates.

EFFECT: black plates treated using said method are highly corrosion resistant, have good adhesiveness with paints and organic coatings, and are very well suited as a substitute for tin-free steel sheet and tin plate for the production of packages, in particular cans.

13 cl, 1 tbl