AFC FAST Status Report Fiscal Year 2025

Beausoleil, Boone [Idaho National Laboratory] (ORCID:0000000238377685); Murdock, Christopher J [Idaho National Laboratory] (ORCID:0009000631684419); Stockwell, Jake [Idaho National Laboratory]; Fielding, Randall S [Idaho National Laboratory] (ORCID:0000000169934379); Bascom, Andrew John [Idaho National Laboratory] (ORCID:0009000566915128); Swearingen, Alexander Lee [Idaho National Laboratory] (ORCID:000900064719238X); Yao, Tiankai [Idaho National Laboratory] (ORCID:0000000183307638); Zirker, David Laurence [Idaho National Laboratory]; Jacobsen, Todd Lynn [Idaho National Laboratory]; Maupin, Jakeob [Idaho National Laboratory]; Hawkins, Katie [Idaho National Laboratory]; Baird, Katelyn Marie [Idaho National Laboratory]; Capriotti, Luca [Former INL]

DOE OSTI · 3374699

AFC FAST Status Report Fiscal Year 2025

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Abstract

The Fission Accelerated Steady-state Test (FAST) methodology has been used to test several innovative metallic fuel designs for use in Sodium?cooled Fast Reactors (SFRs). The FAST method utilizes geometrically scaled fuel pins to produce improved burnup rates for fuels while maintaining semi-prototypic thermal conditions. This report provides a summary description of the test matrix and test objectives for the AFC FAST irradiation campaign as well as details of the as-built conditions for all rodlets. This report also include status update on the irradiation conditions for the rodlets as well as post-irradiation examination (PIE) results on low to mid?range burnup fuel rodlets and a summary power history for those rodlets. A brief discussion provides some early interpretation of the results and whether or not FAST is producing results typical of metallic fuels. Lastly, an outlook for the work expected to be completed in fiscal year (FY) 2026 is also included.

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Beausoleil, Boone [Idaho National Laboratory] (ORCID:0000000238377685), Murdock, Christopher J [Idaho National Laboratory] (ORCID:0009000631684419), Stockwell, Jake [Idaho National Laboratory], Fielding, Randall S [Idaho National Laboratory] (ORCID:0000000169934379), Bascom, Andrew John [Idaho National Laboratory] (ORCID:0009000566915128), Swearingen, Alexander Lee [Idaho National Laboratory] (ORCID:000900064719238X), Yao, Tiankai [Idaho National Laboratory] (ORCID:0000000183307638), Zirker, David Laurence [Idaho National Laboratory], Jacobsen, Todd Lynn [Idaho National Laboratory], Maupin, Jakeob [Idaho National Laboratory], Hawkins, Katie [Idaho National Laboratory], Baird, Katelyn Marie [Idaho National Laboratory], Capriotti, Luca [Former INL]. 2025-09-18. AFC FAST Status Report Fiscal Year 2025. https://www.osti.gov/biblio/3374699

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