Authors: S Ningshen M Sakairi K Suzuki S Ukai
Publish Date: 2013/08/03
Volume: 18, Issue: 2, Pages: 411-425
Abstract
In spent fuel nuclear reprocessing plant nitric acid is the main medium used in PUREX method The passive film compositions and corrosion resistance of 11 Cr ferritic/martensitic and 9–15 Cr oxide dispersion strengthened steels in different nitric acid concentrations were studied The open circuit potential is shifted toward more noble potential as the concentrations increased from 1 M HNO3 to 9 M HNO3 in all the investigated alloy steels The results of the potentiodynamic polarization plots also exhibited a shift in corrosion potential as the concentrations increased from 1 M to 9 M HNO3 This shift is undesirable because of risk of overshooting the potential beyond passive region and may result into transpassive corrosion The Xray photoelectron spectroscopy results of the passive film analysis are composed mostly of Fe2O3 Cr2O3 and Y2O3 and the depth profile of Fe and Cr concentrations vary depending upon the nitric acid concentration The surface morphology after the corrosion test does not show intergranular corrosion attack at the nitric acid concentrations studied It is desirable that materials for use in nitric acid service are resistant to such corrosion induced degradation
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