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IMPACT-01 Assembly Overview [Slides]

Sanches, David M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0009000373369570)·Downey, Calvin Myer [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]
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Abstract

The Irradiated Material Properties Accelerated Characterization Test (IMPACT) series of experiments will irradiate three metallic fuel alloy specimens with embedded thermal conductivity probes in the Advanced Test Reactor (ATR). Metallic fuel alloys have long been under investigation for use in advanced reactors on account of their high thermal conductivity. Metallic fuel undergoes dramatic microstructural changes early in life due to fission gas swelling until ~2-3 at% burnup when pores interconnect, thus allowing fission gas to escape into the fuel pin plenum and swelling effectively ceases. The evolution of metallic fuel thermal conductivity during this early phase has never been successfully measured in situ. This experiment will be designed to use advances in measurement sciences to characterize how thermal transport properties evolve while in reactor. The IMPACT experiment consists of three metallic fuel rodlets with thermal conductivity probes axially centered within the fuel specimen. This presentation is an overview of the IMPACT-01 assembly process with a focus MFC fuel fabrication and experiment assembly steps.

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Sanches, David M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0009000373369570), Downey, Calvin Myer [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]. 2025-09-30. IMPACT-01 Assembly Overview [Slides]. https://doi.org/10.2172/3394708

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