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DOE OSTI · 1872988

EPMA-Based Mass Balance Method for Quantitative Fission Product Distribution Comparison between TRISO Particles

Wright, Karen E.·Stempien, John D·Van Rooyen, Isabella J
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Abstract

Two irradiated AGR-2 TRISO particles were chosen to demonstrate a recently developed mass balance technique in which EPMA-generated concentration data was used to determine fission product mass on a layer-by-layer basis in TRISO particles. EPMA-calculated fission product masses for most fission products in the two particles were within +/- 20% of their ORIGEN-modelled masses. Results show that Sr, Ba, and Eu accumulate preferentially in the carbon-rich kernel periphery on the particles’ side that lacks a gap between the buffer and IPyC. In addition, the more mobile elements--Cs, Sr, and Pd, accumulate in greater quantity in the outer layers of particle AGR2-223-RS34 compared to particle AGR2-223-RS06, which has relatively more of those elements’ mass located in the kernel and kernel periphery, suggesting enhanced fission product transport in particle AGR2-223-RS34. This model can be used better understand and test fission product transport in TRISO particles.

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11 NUCLEAR FUEL CYCLE AND FUEL MATERIALSEPMAelectron probe microanalysisirradiated TRISO

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Wright, Karen E., Stempien, John D, Van Rooyen, Isabella J. 2022-02-03. EPMA-Based Mass Balance Method for Quantitative Fission Product Distribution Comparison between TRISO Particles. https://doi.org/10.1557/s43580-021-00166-2

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