Reactor Pressure Vessels
Goal
The most life-limiting structural component in light-water reactors is the reactor pressure vessel (RPV) because its replacement is not currently considered a viable option. Thus, this research area’s goal is to examine and understand the influence of irradiation at high fluences on RPV embrittlement. Additional goals include obtaining data from high fluence surveillance capsules and harvested RPV materials to validate RPV embrittlement prediction models.
Outcome
Research is directed at removing gaps in the knowledge of RPV performance under long-term aging conditions and incorporating this knowledge into a model that can be used by the industry to make informed aging management decisions and by the U.S. Nuclear Regulatory Commission to improve guidance.
Planned Major Accomplishments
- Development of a new predictive embrittlement trend curve for RPV materials.
- Verification of the latest embrittlement trend curve on materials harvested from the decommissioned Zion Unit 1 RPV and the Palisades high fluence surveillance capsule.
- Development of mini-CT (compact tension) specimens for fracture toughness characterization of RPV materials.
![Representative atom maps showing the presence of Cu-rich precipitates within the Fe matrix
[Edmondson et al., JNM 545 (2021) 152740]](https://lwrs.inl.gov/content/uploads/11/2024/03/Atom-Map.jpg "Atom Map")
