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A study of the sea atmosphere influence on the corrosion products of steel constructions near Sochi at difference distances from the sea has been made. The phases and compositions of the corrosion products formed on different sides of steel construction elements were examined by using Mössbauer spectroscopy (at 298 and 78 K). The results show that phases and composition distributions in oxide films are different on different parts of the constructions. The differences depend not only on the distance from the sea, but from their relative orientation to the sea also. The phase structure of the oxide films on different positions is identified.

The oxidation states of minor alloying elements in Zircaloys often determine their resistance to corrosion, especially in reactors. In particular, tin is of interest because of its near ubiquitous use in earlier Zircaloys. To study changes in the oxidation state of tin under irradiation, specimens of Zr-0.76Fe-1.6Sn were corroded at similar conditions in an autoclave and in a nuclear reactor. Corrosion rates were found to be significantly accelerated following irradiation compared to those in the autoclave. Mössbauer spectroscopy revealed that in both the autoclave conditions and reactor conditions, a combination of tetravalent, divalent, and elemental (β-Sn) tin particles are formed during the initial corrosion processes. The kinetics of both the change in tin oxidation state and the corrosion rate in-reactor are greatly accelerated, pointing to the effect of irradiation driving tin into solution more quickly.

Data were obtained with the help of 57 Fe Mössbauer spectroscopy about the redistribution of iron atoms between intermetallic precipitates and between precipitates and the solid solution phase in E635-type alloy (Zr-1.2 wt% Sn-0.34 wt% Fe-1.0 wt %Nb-0.03-0.05 wt% O) due to neutron irradiation.