Correlation of local parameters of brittle crack initiation and propagation with the fracture toughness of VVER-1000 pressure vessel steels

摘要

Base metal of the VVER-1000 reactor pressure vessel steel in the unirradiated state was studied. The purpose of the work was to find a correlation between local fracture microparameters and macroparameters of samples under quasi-static loads. Fracture toughness tests of steel were performed in the transition temperature region. Structural parameters and brittle fracture origin types were defined by means of fractographic analysis of the tested samples. The stress-strain state of the studied samples at brittle fracture initiation moment was calculated using the complex experimental-calculative method.