Anodic Behavior and Oxidation of Thallium-Containing Alloy Zn22Al

This paper presents potentiodynamic and thermogravimetric data on the anodic behavior and oxidation of thallium-containing alloy Zn22Al in different media. We have determined anodic, kinetic, and energetic characteristics of the alloys under isothermal conditions. The electrochemical corrosion, pitting, and repassivation potentials of the thallium-containing alloys are shifted to positive values. The addition of 0.1–1.0 wt % thallium to alloy Zn22Al leads to an increase in its anodic oxidation resistance. The oxidation and corrosion rates of the thallium-containing (0.01–0.1%) alloys are a factor of 1.5–2 lower than those of alloy Zn22Al. The oxidation products of the alloys consist of a mixture of protective ZnO, Al2O3, Tl2O3, and ZnAl2O4 oxide films.