Post-radiation annealing influence on the evolution of the materials properties of the supporting structures of WWER-440 reactor vessels. Part 2: Analysis of the influence of material annealing after low temperature irradiation

Abstract

The results of studying the influence of annealing temperature on the restoration degree of the materials properties of WWER-440 reactor vessels supporting structures (low-strength ferritic-pearlitic steel and its weld metal) irradiated at low temperatures (50–90°C) are analyzed. The main processes that occur during the annealing of the supporting structures materials after low-temperature irradiation and lead to an ambiguous effect of the annealing temperature on the recovery degree of the properties of supporting structures materials are revealed. The influence of impurities (phosphorus and copper) on the embrittlement of the material during irradiation and on the recovery of its properties after annealing is considered.