An atom probe tomography study of the chemistry of radiation-induced dislocation loops in Zircaloy-2 exposed to boiling water reactor operation

• Zircaloy-2 was analysed after in-reactor exposure using APT in voltage mode. Clusters of Fe and Ni were disc-shaped, clusters Cr spheroidal. Fe–Ni Fe–Cr seem to be associated with radiation-induced -loops. segregation the loop plane. smaller denser than clusters. This study is complementary previous atom probe tomography (APT) studies irradiation effects zirconium alloy Zircaloy-2. Using pulse mode, a difference morphology observed between exposed high fast neutron fluence commercial boiling water reactor. The disc-shaped diameter 5–15 nm, whereas spheroidal approximately 5 nm. Both types appeared located at irradiation-induced -type dislocation loops aligned layers normal -direction. concentration higher dilute clusters, which inside loops, had formed on all three families first-order prismatic planes some deviation from perfect -axis alignment. might very small precipitates nucleation loops.