Reverse pulse electrodeposition of Zn–Ni alloys from a chloride bath

The properties of electrodeposited zinc–nickel alloys including corrosion resistance are largely controlled by their chemical compositions and structures. The present work systematically investigates the influence of pulse parameters for the reverse pulse electrodeposition of zinc–nickel alloys in a chloride bath on the composition and structure of the deposits. Different degrees of zinc and nickel dissolutions occur upon varying the anodic current density between 0 and 0.1 A/cm2, yielding γ-phase coatings with nickel content ranging from 11 to 17 wt.%. Deposits with much higher nickel content are obtained by prolonging the dezincification period with increased pulse reverse duration. Furthermore, anodic pulse can also introduce grain refinement and pore formation to the structure. Effective tailoring of the zinc–nickel alloys’ characteristics has been demonstrated using the reverse pulse plating technique.