Determination of the Lower Temperature Limit of Void Swelling of Stainless Steels at Relatively Low Displacement Rates
An issue of current interest to PWRs is the possibility that void swelling of austenitic near-core internal components may exert some deleterious effect on component functionality, particularly during extended operation to 60 years. A similar concern has also been raised for water-cooled fusion devices. One question of particular interest is the range of temperature over which void swelling can occur, since the internal components experience temperatures from ~290 to perhaps as high as 390 degrees C in some limited locations. This question was addressed using a flow restrictor component from the low-flux breeder zone of the BN-350 fast reactor in Kazakhstan. This component was constructed of annealed 12X18H10T, an alloy similar to AISI 321 which is used in Russian reactors for applications where AISI 304L would be used in comparable Western and Japanese reactors. Extensive sectioning to produce 114 separate specimens, followed by examination of the radiation-induced microstructure showed that void swelling in the range of temperatures and dpa rates of PWR interest occurs down to ~305 degrees C. At 330 degrees C the swelling reached ~1% at 20 dpa. Comparison of these data with other published results from Russian LWR reactors at <10 dpa confirms that the lowest temperature that stainless steels can begin swelling appears to be ~300 degrees C. Since fusion and PWR spectra generate similar levels of hydrogen and helium, it is expected that these conclusions are also application to fusion devices operating at comparable dpa rates.
- Research Organization:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1002206
- Report Number(s):
- PNNL-SA-31898; AT6020100
- Country of Publication:
- United States
- Language:
- English
Similar Records
Determination of the Lower Temperature Limit of Void Swelling of Stainless Steels at PWR-Relevant Displacement Rates
Void Swelling at Low Displacement Rates in Annealed X18H10T Stainless Steel at 4 to 56 DPA and 280-332 degrees centigrade