Influence of the Parameters of Feed Water of the WWER-1000 Reactors on the Corrosion-Electrochemical Behavior of 08KH18N10T Steel.

We study the influence of the temperature and composition of the feed water of ammonia-hydrazine control on the corrosion-electrochemical behavior of 08Kh18N10T stainless steel. It is shown that, as temperature increases from 25 to 300°С, the corrosion currents increase by more than an order of magnitude for hydrazine concentrations of 0-2.0 mg/kg, by 1.5-2 orders of magnitude depending on the concentration of chlorides, and by two orders of magnitude within the рН range 6.9-9.0. We plot the dependences of the susceptibility of steel to pitting and repassivation on temperature, on the concentrations of hydrazine and chloride ions, and on the рН value. It is shown that, for a content of chloride ions of 2.0 mg/kg and рН 6.9, the analyzed steel is most susceptible to the initiation of pits within the range 25-300°С. [ABSTRACT FROM AUTHOR]