Electrochemical Research of Corrosion behavior of Steels in Water-Chemical Conditions of the Third Circuit of FN-type reactors

6/30/2025 2025 - #02 Nuclear materials

Smykov V.B. Legkikh K.G. Askhadullin S.R.

https://doi.org/10.26583/npe.2025.2.05

The results of the study of corrosion resistance of the most common structural steels of the reverse steam generator (10H2M-HP – steam generator tubes and 12H1MF – reverse steam generator body) under conditions simulating the adopted water chemistry modes of fast neutron reactors with sodium coolant were obtained As a result of the study, it was established that under conditions simulating feedwater, both grades of steel are not subject to corrosion Pitting corrosion is observed in concentrated solutions simulating the evaporation zone (the drying zone of residual moisture)of a reverse steam generator with neutral non-corrective water chemistry Under conditions simulating oxygen-ammonia water chemistry in the evaporation zone, both grades of steel are not prone to corrosion It has been established that the most unfavourable conditions for the development of corrosion processes in steels occur with neutral non-corrective water chemistry The most favourable conditions for the passivation of steels and the extension of their service life, according to the results of the study, occur with oxygen-ammonia water chemistry The intensity (magnitude of current density) of electrochemical corrosion of 12H1MF steel with neutral non-friction water-chemical regime in the evaporation zone is about 2 orders of magnitude higher than with oxygen-ammonia water-chemical mode The intensity of electrochemical corrosion of 10H2M- HP steel with neutral non–friction water-chemical regime in the evaporation zone is about 1.5-2.0 orders of magnitude higher than with oxygen-ammonia water-chemical mode. It has been shown that in the evaporation zone, when two steel grades come into contact, an electrochemical galvanic effect is observed.

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water chemistry regime corrosion evaporation zone feed water anodic polarization curve method

Link for citing the article: Smykov V.B., Legkikh K.G., Askhadullin S.R. Electrochemical Research of Corrosion behavior of Steels in Water-Chemical Conditions of the Third Circuit of FN-type reactors. Izvestiya vuzov. Yadernaya Energetika. 2025, no. 2, pp. 50-57; DOI: https://doi.org/10.26583/npe.2025.2.05 (in Russian).