Anodic Behaviour of Electrodeposited Zn-Sn Alloys

Abstract

SummaryThe paper discusses the anodic behaviour of the electrodeposited alloys Zn-15%Sn in comparison with pure Zn coatings in 0.5M Na2SO4 and 5% NaCI. A passive state in 0.5M Na2SO4 medium was registered for the alloy while in 5% NaCI the typical passive state was not observed. The selective dissolution of Zn-Sn coatings in media of 0.5 M Na2SO4, and 5% NaCI under the effect of anodic polarisation in the active state was investigated. Strong selective dissolution of some of the alloy components was not established.The elemental and chemical compositions of the surface layers formed on ZnSn coatings after anodic treatment in 0.5 M Na2SO4 were studied by X-ray photoelectron spectroscopy (XPS). A gradual tin-enrichment of the surface layer was established.The changes in the structure and morphology of the studied galvanic alloy in 0.5 M Na2SO4 under the influence of different corrosion-electrochemical treatments were investigated.