Ring-tensile properties of irradiated oxide dispersion strengthened ferritic/martensitic steel claddings

The effects of fast neutron irradiation on ring-tensile properties of the oxide dispersion strengthened (ODS) ferritic/martensitic steel claddings with improved microstructural isotropy from recrystallization and α–γ phase transformation were investigated. The samples were irradiated in the experimental fast reactor JOYO using the material irradiation rig at temperatures between 670 and 807 K to fast neutron fluences ranging from 5.0 × 1025 to 3.0 × 1026 n/m2 (E>0.1 MeV). The post-irradiation ring-tensile tests were carried out on samples with five sets of irradiation conditions. The experimental results showed that strengths were increased by 10% due to irradiation. Microstructural improvement considerably increased elongations for these samples and specimens retained respectable elongation after irradiation. The ring-tensile properties of these ODS steel claddings remain excellent within the fluence level achieved in this study.