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DOE OSTI · 3374574

Multi-scale modeling of wastage layer formation in metallic fuel cladding

Aagesen Jr, Larry Kenneth [Idaho National Laboratory] (ORCID:000000034936676X)·Hirschhorn, Jacob Aaron [Idaho National Laboratory] (ORCID:0000000302425902)·Jiang, Chao [Idaho National Laboratory] (ORCID:0000000306106327)·Beausoleil, Boone [Idaho National Laboratory] (ORCID:0000000238377685)
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Abstract

Fuel-cladding chemical interaction (FCCI) is a major concern for U-Zr metallic fuels' performance, primarily due to the formation of a brittle layer (wastage) in the cladding. This brittle layer, resulting from intermetallic compounds between cladding constituents Fe, Cr, and lanthanide fission products, significantly impacts the cladding's mechanical integrity. Recent efforts focus on developing a mechanistic modeling framework to understand lanthanide production, transport to the fuel-cladding interface, and phase transformation to intermetallic phases. A multi-scale computational approach has been used to calculate lanthanide transport rates, with atomistic calculations determining Nd diffusivities through the solid fuel matrix and along pore surfaces. These diffusivities inform a mesoscale model to determine an effective diffusion coefficient, accounting for porosity and infiltration with bond sodium. This effective diffusivity is used in engineering-scale simulations via the BISON fuel performance code, which has been validated against EBR-II and FFTF reactor experiments.

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11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS36 - MATERIALS SCIENCEcladdingFCCImetallicwastage

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Aagesen Jr, Larry Kenneth [Idaho National Laboratory] (ORCID:000000034936676X), Hirschhorn, Jacob Aaron [Idaho National Laboratory] (ORCID:0000000302425902), Jiang, Chao [Idaho National Laboratory] (ORCID:0000000306106327), Beausoleil, Boone [Idaho National Laboratory] (ORCID:0000000238377685). 2025-09-30. Multi-scale modeling of wastage layer formation in metallic fuel cladding. https://www.osti.gov/biblio/3374574

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