Abstract
The corrosion cracking phenomena of electro-deposited Zn-Ni alloy layers were investigated in relation to the coating structures. Zn-Ni alloy layers with nickel content over 10%, corresponding to γ single phase are subject to the corrosion cracking at potential more noble than their corrosion potential in an aqueous solution. The corrosion cracking of these layers can be prevented by thermal treatment at temperatures above 450°C. The corrosion cracking seems to occur by internal tensile stress generated by preferential dissolution of a small amount of zinc in Zn-Ni alloy layers.
