Zircaloy-4 oxidation at 1300 to 2400/sup 0/C

Technical Report · Wed Apr 01 04:00:00 EST 1987

OSTI ID:6490513

Prater, J T; Courtright, E L

The oxidation kinetics of Zircaloy-4 in steam have been extended to 2400/sup 0/C. The ZrO/sub 2/ and ..cap alpha..-Zr layers display parabolic growth behavior over the entire temperature range studied. A discontinuity in the oxidation kinetics at 1510/sup 0/C causes rates to increase above those previously established by the Baker-Just relationship. This increase coincides with the tetragonal-to-cubic phase transformation in ZrO/sub 2-x/. No additional discontinuity in the oxide growth rate was observed when the metal phase melted. The effects of temperature gradients were taken into account, and corrected values representative of near-isothermal conditions were computed. Oxide growth was also measured in various steam-hydrogen mixtures at 1565/sup 0/C and 1815/sup 0/C. Hydrogen concentrations up to 90 mol% had no effect on oxidation kinetics. The rate-controlling factor appears to be diffusion through the oxide layer. Finally, the oxidation kinetics of prereacted Zircaloy-15 mol% UO/sub 2/ were measured at 1400 to 2150/sup 0/C. The rates were comparable to those obtained for Zircaloy above 1500/sup 0/C.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA); Nuclear Regulatory Commission, Washington, DC (USA). Div. of Reactor Systems Safety
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6490513
• Report Number(s): NUREG/CR-4889; PNL-6166; ON: TI87008841
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220300 -- Nuclear Reactor Technology-- Fuel Elements
36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ACCIDENTS
ALLOYS
CHEMICAL REACTIONS
CRYSTALLIZATION
FUEL CANS
FUEL ELEMENTS
LOSS OF COOLANT
MATERIALS
METALLOGRAPHY
OXIDATION
PHASE TRANSFORMATIONS
REACTOR ACCIDENTS
REACTOR COMPONENTS
REACTOR MATERIALS
STEAM
TEMPERATURE GRADIENTS
TIN ALLOYS
VERY HIGH TEMPERATURE
ZIRCALOY
ZIRCALOY 4
ZIRCONIUM ALLOYS
ZIRCONIUM BASE ALLOYS