THE THEORETICAL AND CALCULATION ANALYSIS OF OXIDE FORMATION PROCESS ON STEEL IN LEAD COOLANT

Authors & Affiliations

Alekseev V.V., Orlova E.A., Kozlov F.A., Torbenkova I.Ju., Kondratev A.S.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia

Abstract

Two models of steel oxidation in lead coolant have been developed for the cases with prevailing mechanism of magnetite formation and formation of two-layer oxide film on steel surface. Based on the first model, the permeability constants for magnetite in lead were calculated using available experimental data. The temperature dependence of permeability coefficient for iron in oxide film on steel EI-852 is: Кpr = 10-(4,69+7040/Т), кг/(м·с). The second model involves the mathematical description of oxidation process at simultaneous formation of magnetite and iron-chromium spinel layers of oxide film. The simultaneous solution of the equations obtained under the given boundary conditions allows the formation dynamics of each oxide sublayers and their thickness to be calculated. The agreement between calculated and experimental data on steel EI-852 oxidation has been obtained at aО=0.01 and t=650 °С. As it follows from the calculations, the magnetite mechanism of oxide film formation prevails at oxygen activity in lead from 1 up to 10-3 for the conditions under consideration. At oxygen activity of 10-4 and lower, only the iron-chromium spinel mechanism of oxidation is the case.

Keywords
lead coolant, model, steel oxidation, magnetite, permeability constants, oxide sublayers, oxide film, oxidation mechanism

Article Text (in Russian, PDF)

References

UDC 539.17

Problems of Atomic Science and Technology. Series: Nuclear Constants, issue 1-2, 2010