MANUFACTURE OF STEEL PLATE ELECTROPLATED WITH NI-ZN ALLOY AND PROVIDED WITH SUPERIOR WORKABILITY AND CORROSION RESISTANCE

摘要

PURPOSE:To manufacture the titled plated steel plate by plating a steel plate at high current density in a plating bath having specified concns. of Zn2+ and Ni2+ and a pH below an upper limit value determined in accordance with the relative speed of the bath to the plate and the composition of the bath. CONSTITUTION:A plating bath contg. =20g/l Zn2+ while satisfying Ni2+/Zn2++ Ni2+)=0.55-0.90 and having a pH below a valve defined by the equation [where v is the relative speed (m/sec) of the bath and a steel plate, Zn2+ is the concn. of Zn2+, and Ni2+ is the concn. of Ni2+] is used. A steel plate electroplated with an Ni-Zn alloy and provided with superior workability and corrosion resistance can be obtd. by carrying out plating in said plating bath at high current density.