Flux effect analysis in WWER-440 reactor pressure vessel steels

Microstructural studies show that copper content decreases in the ferrite matrix and that there is formation of copper-enriched clusters and precipitates under irradiation and subsequent thermal annealing. Due to this fact the radiation damage does not depend on copper re-irradiation after annealing. Dependence of transition temperature shift on neutron flux is not expected for WWER-440 steels under re-irradiation after annealing.