Thermal annealing as a method to predict results of high temperature irradiation embrittlement

In order to assess the validity of post-irradiation annealing as a method to predict results of high temperature irradiation a new analysis of experimental data has been performed revealing the combined influence of annealing temperature and impurities content on residual embrittlement after annealing. For 2CrMoV (WWER-440 reactor pressure vessel) steel with low contents of copper and phosphorus, the comparison of two embrittlement dependencies has been done: on irradiation temperature and post-irradiation annealing temperature. It is demonstrated that data for both the transition temperature shift after irradiation, ΔTk, and the residual transition temperature shift after post-irradiation annealing, ΔTres, fall within the same scatter band. A similarly close correlation is observed by comparison of yield strength increases after irradiation and after post-irradiation annealing.