Examination of Zircaloy-clad spent fuel after extended pool storage

Technical Report · Tue Sep 01 04:00:00 EDT 1981

DOI:https://doi.org/10.2172/5915801· OSTI ID:5915801

Bradley, E R; Bailey, W J; Johnson, Jr, A B; Lowry, L M

This report presents the results from metallurgical examinations of Zircaloy-clad fuel rods from two bundles (0551 and 0074) of Shippingport PWR Core 1 blanket fuel after extended water storage. Both bundles were exposed to water in the reactor from late 1957 until discharge. The estimated average burnups were 346 GJ/kgU (4000 MWd/MTU) for bundle 0551 and 1550 GJ/kgU (18,000 MWd/MTU) for bundle 0074. Fuel rods from bundle 0551 were stored in deionized water for nearly 21 yr prior to examination in 1980, representing the world's oldest pool-stored Zircaloy-clad fuel. Bundle 0074 has been stored in deionized water since reactor discharge in 1964. Data from the current metallurgical examinations enable a direct assessment of extended pool storage effects because the metallurgical condition of similar fuel rods was investigated and documented soon after reactor discharge. Data from current and past examinations were compared, and no significant degradation of the Zircaloy cladding was indicated after almost 21 yr in water storage. The cladding dimensions and mechanical properties, fission gas release, hydrogen contents of the cladding, and external oxide film thicknesses that were measured during the current examinations were all within the range of measurements made on fuel bundles soon after reactor discharge. The appearance of the external surfaces and the microstructures of the fuel and cladding were also similar to those reported previously. In addition, no evidence of accelerated corrosion or hydride redistribution in the cladding was observed.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5915801
• Report Number(s): PNL-3921; ON: DE82001846
• Country of Publication: United States
• Language: English

Related Subjects

050900* -- Nuclear Fuels-- Transport
Handling
& Storage
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
ALLOYS
BURNUP
DATA
EXPERIMENTAL DATA
FUEL ELEMENTS
FUEL POOLS
INFORMATION
METALLOGRAPHY
NUMERICAL DATA
PWR TYPE REACTORS
REACTOR COMPONENTS
REACTORS
SPENT FUEL ELEMENTS
SPENT FUEL STORAGE
STORAGE
TIN ALLOYS
WATER COOLED REACTORS
WATER MODERATED REACTORS
ZIRCALOY
ZIRCONIUM ALLOYS
ZIRCONIUM BASE ALLOYS