Radiation-induced segregation and void swelling in 304 stainless steel

Void swelling and radiation-induced segregation have been measured in 304 stainless steel. Samples were irradiated in the outer regions of the EBR-II reactor where displacement rates of 2.0×10^-8 and 6.6×10^-8 dpa/s are comparable to those in pressurized water reactor components. Samples were irradiated at temperatures from 371-390°C to total doses of up to 20 dpa. Void swelling reached a maximum of 2 % at 20 dpa. Nickel enrichment and chromium depletion to of 20 at% and 12 at% respectively were measured. Both void swelling and radiation-induced segregation were dependent on dose rate, increasing as the dose rate decreased. Grain boundary compositions were measured both near and in areas free of precipitates. The presence of a precipitate significantly changes the grain boundary compositions near the precipitate.