Electrical coating of steel strip - using zinc on zinc-nickel alloy then treating strip as anode in electrolyte soln.

摘要

Steel strip is electrolytically coated on one side with Zn or ZnNi alloy and then treated as anode in electrolyte contg. 0.1-10, pref. 1 g/l urea, 50-200, pref. 100 g/l Na sulphate, and 10-50, pref. 30 g/l citric acid, at pH 8-9 and bath temp. 40-70 deg.C, pref. 60 deg.C. Current density is e.g. 50 A/dm2 and treatment time 3 sec.. USE/ADVANTAGE - Vehicle body strip, unwanted coating being removed from uncoated side of strip.