Changes in the Structure of Irradiated Steel 0.12C18Cr10NiTi Caused by Plastic Deformation at Different Temperatures

The results of a fractographic study of the fracture surface of samples of irradiated steel 0.12C18Cr10NiTi after tensile tests at temperatures of 24, 350, 450 °C are presented Samples for studies were prepared from the faces of the hexagonal assembly ducts of the fast neutron reactor BN-350 after irradiation with sodium and subsequent storage of water in the reactor. It is shown that with increasing test temperature, the plastisity of steel decreases. Based on the analysis results, it was concluded that a decrease in the ductility of steel with an increase in the test temperature may be due to a change in the fracture mechanism under the action of shear stresses, which was facilitated by local increase in the porosity of the material as a result of grains accommodation processes of the rotational type.