Mechanical characterization of synergistic thermal and irradiation effects on fracture resistance of stainless steel

This study investigates the synergistic effects of thermal aging and neutron irradiation on the fracture resistance of austenitic stainless steel used in nuclear power plant reactor internals. Thermal aging and irradiation environments are known to reduce fracture resistance, posing risks to the structural integrity of critical components. Considering the high temperature and neutron irradiation environments, which deteriorate the fracture resistance, this study simulates the J-R curves to evaluate the integrity of austenitic stainless steel used in reactor internals. The analysis includes thermal aging at 295 °C for 118,000 h and irradiation dose of 0.4 dpa. The results demonstrate a reliable method for predicting material fracture behavior under prolonged exposure to high temperatures and neutron irradiation, which is essential for the effective lifecycle management of nuclear reactors. This research provides critical insights and practical approaches for ensuring the long-term safety and performance of nuclear power plants.