| abstract |
PURPOSE: To obtain the plated steel plate of superior white rusting resistance even without applying special post-treatment by electroplating a steel plate in the bath comprising adding ions such as of Cr, V, W, etc. as third components to a zinc- nickel alloy plating bath. n CONSTITUTION: With a steel plate as a cathode, it is electroplated in the acidic plating solution comprising adding one or more kinds of Cr(III) (e.g.: chromium sulfate), Cr(VI) (e.g.: chromate), V(II) (e.g.: VSO 4 ), V(III) ( e.g.: vanadic sulfate), V(IV) (e.g.: vanadyl chloride), V(V) (e.g.: vanadate), W(VI) (e.g.: ammonium tungstate) as third components to a zinc-nickel plating bath (molar ratio of Zn:Ni is 1:0.1W2, preferably 1:05W1.0), whereby the high corrosion-resistant electroplated steel plate is obtained. The addition amounts of the third components are 0.001W0.5mol, preferably 0.05W0.2mol, of Cr, 0.001W 0.5mol, preferably 0.01W 0.5mol, of V and 0.0001W0.5mol of W, based on 1mol of the sum of Zn and Ni. n COPYRIGHT: (C)1980,JPO&Japio |