Production manner null of the Cr content spelter alloy based organicity distributed plated steel sheet which is superior corrosion-resistant and

摘要

PURPOSE:To produce a steel sheet dispersion-plate with Cr-contg. zinc alloy-org. matter and having superior adhesion of the upper plating layer by adding a certain amt. or more of SO32- to a plating soln. CONSTITUTION:When the surface of a steel sheet is electroplated with a plating soln. for dispersion plating with Cr-contg. zinc alloy-org. matter, =1ppm SO32- is added to the plating soln. contg. =10g/l Cr3+ and =10ppm cationic polymer and electroplating is carried out while keeping =1ppm SO32-. Since SO32- is present in the plating soln., a reducing effect is produced and a reducing atmosphere is formed by accumulating SO32- around the anode by the anionic property to prevent the generation of Cr6+ and R'(NH3)+(COO)-.