ABSTRACT The article presents the results of a study of high-temperature electrochemical corrosion the Zn55Al alloy doped with indium in various environments. The interaction of the Zn55Al alloy doped with indium with atmospheric oxygen in the temperature range about 473-623 K, in the solid state, was investigated by thermogravimetric method. Oxidation parameters of the high-temperature oxidation of alloys were evaluated at the solid state. It is shown that additions of indium in the range of 0.01-0.05 wt% insignificantly increase the oxidizability of the initial alloy, and the oxidation products of the alloys are Al2O3, ZnO, In2O3 oxides. The effect of additive indium on the corrosion behavior of the Zn55Al alloy in a neutral medium of 0.03%, 0.3%, and 3% NaCl was studied by a potentiostatic method. It was found that with an increase in the concentration of sodium chloride electrolyte and alloying component, the corrosion potential decreases, which indirectly indicates a decrease in the anticorrosion resistance of alloys as the aggressiveness of the corrosive environment increases. It was revealed that alloys are most resistant to pitting corrosion in an electrolyte environment of 0.03 and 0.3% NaCl. Alloys with additive indium within 0.01-0.1 wt% have low values of anodic corrosion rate as compared to the initial alloy. The corrosion rate of alloyed alloys with indium is 1.5-3 times lower than the initial Zn55Al alloy. Additive indiums within the range of 0.01-0.1 wt% have a particularly positive effect. The proposed compositions of zinc-aluminum alloys containing indium can be used as anodic coatings for corrosion protection of steel products.
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