Microstructural analysis of impurity segregation around β-Nb precipitates in Zr-Nb alloy using positron annihilation spectroscopy and atom probe tomography

Fe segregation are evident at the interface between β-Nb precipitates and α-Zr matrix by atom probe tomography (APT). Defects are observed at the interface by positron annihilation spectroscopy. It is also suggested that Fe was segregated to a concentration of several tens of percent at a local region at the interface, which is approximately one order of magnitude higher than APT and difficult to observe directly even using APT.214