Potentiodynamic Studies of the Anodic Behavior of Zn-Ni Alloys Electroplated from Acetate-Chloride Baths

The potentiodynamic anodic behavior of zinc, nickel, and their alloy is studied depending on the compositions of both the electrolyte for dissolution and electroplates to be dissolved. Zinc deposits are indifferent to the presence of chloride ions in solutions. However, the latter ions strongly affect the anodic behavior of Ni and Zn-Ni alloy. The curves of increasing the polarization of the alloys containing more than 70% Ni demonstrate peaks corresponding to the dissolution of both the Zn-Ni solid solution in a range from -0.2 to +0.2 V and nickel in a range from 0.6 to 0.9 V. For alloys containing less than 31% Ni, no peak of its anodic dissolution is observed, because all Ni is bound with Zn.