Oxidation behavior of beta-Nb precipitates in Zr-1Nb-0.2Bi alloy corroded in lithiated water at 360 degrees C

摘要

The oxidation behavior of beta-Nb Precipitates in Zr-1Nb-0.2Bi alloy corroded in lithiated water with 0.01 M LiOH at 360 degrees C/18.6 MPa was investigated by high-resolution transmission electron microscopy (HRTEM). From the HRTEM observation and the analysis for the oxide layer, the oxidation behavior of beta-Nb precipitates corroded in lithiated water in early stage is as follows: beta-Nb precipitates are first oxidized to NbO2, then part of it is further oxidized to Nb2O5 in some specific crystallographic orientations. The reason for accelerated corrosion of Zr-Nb alloys in lithiated water is discussed from the rapid oxidation of beta-Nb precipitates. (C) 2015 Elsevier Ltd. All rights reserved.