METHOD FOR PASSIVATION OF STRIP BLACK PLATE

摘要

The invention concerns a process for passivation of strip steel plate, having the following steps: - electrochemical treatment of the black plate by passing the black plate through an electrolyte to form an inert steel surface, - rinsing the black plate, - application of an aqueous chromium-free treatment solution to at least one surface of the black plate to form a conversion layer that protects against corrosion and an adhesion layer for paints and organic coating materials. The black plate treated in accordance with the invention is characterized by high corrosion resistance and has good bonding capacity for paints and organic coatings and therefore is very suitable as a substitute for tin-free steel (TFS or ECCS) and tinplate for the production of packagings, in particular cans. In contrast to the traditional manufacturing and passivation processes for tin-free steel and tinplate, no chromium VI, which is environmentally hazardous and hazardous to health, is used in the process in accordance with the invention.