Influence of Overvoltage During Electrodeposition of Thin Zn-Ni-Cu Alloy Films on Its Phase Composition

The change in the phase composition of Zn-Ni-Cu alloy films in a wide range of potential values and current density of deposition by different modes from an ammonium-glycinate electrolyte for the subsequent design of multilayer coatings based on this alloy are considered. The alloy films are anodically dissolved in the potentiodynamic mode. In this case, the gamma phase of the Zn-Ni alloy and the copper component are selectively oxidized. The latter is copper and, depending on the deposition conditions, solid solutions of zinc and nickel in it. In films obtained under potentiostatic conditions, in contrast to films obtained under galvanostatic conditions, the
$\boldsymbol{\gamma}$
-phase is present in the form of two structures. With an increase in polarization in films obtained under galvanostatic conditions, a more significant increase in the fraction of the phase is observed. The proportion of the Cu-component decreases, and a peak of oxidation of the
$\boldsymbol{\beta}$
-phase of the Zn-Ni alloy appears.