Post-radiation annealing influence on the evolution of the materials properties of the supporting structures of WWER-440 reactor vessels. Part 1: Problem statement and test results

Experimental studies have been carried out regarding the effect of annealing temperature on the degree of properties recovery of supporting structures materials for WWER-440 reactor vessels (low-strength ferritic-pearlitic steel and its weld metal) irradiated at low temperatures (50–90°C). Properties connected with material embrittlement have been determined on the basis of test results of tensile specimens, impact bending specimens and fracture toughness specimens. Dependence of properties recovery coefficient on annealing temperature have been determined. It is shown that for material with high content of copper dependence of properties recovery coefficient on annealing temperature may be nonmonotonic.

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