Hydride Reprecipitation in Prototypical 17x17 PWR Fuel Rods after Simulated Vacuum Drying Conditions
Conference
·
OSTI ID:3002495
- ORNL
- Argonne National Laboratory
Light water reactor (LWR) fuel rod cladding picks up hydrogen as it oxidizes in reactor. Once the hydrogen concentration exceeds the solubility limit, zirconium hydride platelets precipitate, generally in the circumferential direction. In preparation for dry storage, elevated temperatures can dissolve some of the circumferential hydrides, which during cooling can then reprecipitate in a direction perpendicular to the hoop stress (radially). From 2019 to 2024, ORNL published a series of reports that included metallographic observations of cladding after a thermal transient to 400°C followed by slow cooling. The simulated dry storage process was performed on three full-length 17x17 PWR fuel rods at their as-discharged rod internal pressure. There were two important observations from the metallographic examinations of these heat-treated rods: (1) the propensity for hydride reorientation is strongly influenced by nearby as-discharged precipitated hydrides, (2) the radial hydrides observed near the cladding inner diameter were often associated with cracks in the pellet. Subsequent modeling using the BISON fuel performance code that considered the effects of pellet cracks and pellet-cladding bonding observed in high-burnup fuel support the conclusion that pellet cracks enhance the local hoop stress in the cladding creating preferential sites for hydride reorientation, and that the influence of the pellet cannot be ignored in accurate fuel rod performance predictions.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-00OR22725
- OSTI ID:
- 3002495
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of Lower Drying-Storage Temperature on the Ductility of High-Burnup PWR Cladding
Effects of Lower Drying-Storage Temperatures on the DBTT of High-Burnup PWR Cladding
Effects of Radial Hydrides on PWR Cladding Ductility following Drying and Storage
Technical Report
·
Tue Aug 30 00:00:00 EDT 2016
·
OSTI ID:1326598
Effects of Lower Drying-Storage Temperatures on the DBTT of High-Burnup PWR Cladding
Technical Report
·
Fri Aug 28 00:00:00 EDT 2015
·
OSTI ID:1480053
Effects of Radial Hydrides on PWR Cladding Ductility following Drying and Storage
Technical Report
·
Sat Dec 31 23:00:00 EST 2016
·
OSTI ID:1478471