CORROSION STUDY OF ALLOY 22 AND CHARACTERIZATION OF CORROSION PRODUCTS FORMED IN SIMULATED YUCCA MOUNTAIN (YM) WATER

摘要

Alloy 22 (Ni-22Cr-13Mo-3Fe-3W) is a candidate alloy for nuclear materials storage containers in the Yucca Mountain High Level Nuclear Waste Repository as well as for sub-surface applications. In this study, we present the results of our investigation on the corrosion behavior of Alloy 22 as a function of temperature simulated Yucca Mountain (YM) water in deaerated/aerated conditions. Standard electrochemical potentiodynamic tests have been used to determine the passivation behavior of Alloy 22 in simulated YM water. Our results show that, at room temperature, the passive current density for Alloy 22 in aerated conditions was 5×10-7 A.cm-2 compared to 2×10-6 A.cm-2 in deaerated YM water, suggesting aeration is conducive to formation of passive films (that inhibit the corrosion process). Results from Potentiodynamic studies, Scanning Electron Microscope (SEM) coupled with Energy Dispersive X-Ray Microanalysis (EDX) to characterize the passive film at room temperature and at different applied potential are presented.