Abstract
In the electrolytic dissolution of binary alloys the concepts of ionization and redeposition of a metal, coupling of the anodic reactions in accordance with the concepts of irreversible thermodynamics, and volume diffusion in the presence of given supersaturations of single and double vacancies are analyzed theoretically. The ionization‐redeposition mechanism is in principle possible but only if coupling of the anodic reactions occurs. Volume diffusion may be operative via divacancies. Results from x‐ray investigations and from measurements with a rotating disk‐ring electrode for copper‐gold alloy indicate that interdiffusion of the constituent metals in the alloy occurs to a significant extent and dissolution of Au does not take place. Electrochemical measurements with a Cu‐Zn alloy involving 30 a/o (atomic per cent) Zn give no indication of occurrence of the ionization‐redeposition mechanism.