The effects of long-time irradiation and thermal aging on 304 stainless steel

The effect of long-time irradiation and thermal aging on the tensile, fracture, and swelling properties of 304 stainless steel were studied. Samples of cold-worked and annealed 304 were irradiated in EBR-II at temperatures between 371–400°C or thermally aged in the EBR-II primary core basket at 371°C for times up to 18 years. Samples of annealed steel were irradiated in rows 4 and 12 of EBR-II to determine the effect of dose rate. No significant changes in tensile properties or density occurred in cold-worked thermally aged steel. For samples irradiated near 370°C, decreasing the dose rate caused an increase in swelling and had no measurable effect on tensile properties.