Interaction of void-induced phase instability and subsequent void growth in AISI 304 stainless steel

There are two types of radiation-induced phase instabilities that AISI 304 is prone to develop at temperatures in the 400-550 °C range at dpa rates typical of fast reactors, and there is some concern that these instabilities may shift to lower temperatures (≤400 °C) at lower dpa rates typical of pressurized water reactors. One of these instabilities, the void-induced γ→α transformation, is investigated in this study at dpa rates typical of both types of reactors. The mode of nickel segregation shifts somewhat at PWR-relevant conditions, but the γ→α transformation has not yet been observed in the range 380-400 °C for swelling levels less than 2%.