Abstract
An atom probe tomography study of the microstructure of a Zircaloy-2 material subjected to 9 annual cycles of BWR exposure has been conducted. Upon dissolution of secondary phase particles, Fe and Cr are seen to reprecipitate in large numbers of clusters and particles of 1-5 nm sizes throughout the Zr metal matrix. Fe and Sn were observed to segregate to ring-shaped features in the metal that are interpreted to be 〈c〉-component vacancy loops. This implies that these two elements play a major role in the irradiation growth phenomenon in Zr alloys, which is believed to be caused by the formation of 〈c〉-loops. Similarly to autoclave-corroded Zr alloys, the formation of a sub-oxide layer of approximate composition ZrO was observed. On the other hand, no oxygen saturated metal phase was detected underneath the oxide scale.
| Original language | English |
|---|---|
| Pages (from-to) | 178-185 |
| Number of pages | 8 |
| Journal | Journal of Nuclear Materials |
| Volume | 454 |
| Issue number | 1-3 |
| DOIs | |
| State | Published - Nov 2014 |
| Externally published | Yes |
Funding
The authors would like to thank Daniel Jädernäs at Studsvik Nuclear AB and the MUZIC-2 consortium for useful discussions about the manuscript. Financial support was provided by Westinghouse Electric Sweden AB , Sandvik Materials Technology AB , Vattenfall AB , the Electric Power Research Institute , Studsvik Nuclear AB and the Swedish Research Council .