NSUF 25-5338: Investigation of Fission Product Speciation in UN MiniFuel Particles

This work aims to characterize fission product speciation in irradiated UN particles in bare kernel and TRISO configurations. The samples were irradiated in HFIR at ORNL to 6% FIMA. Initial PIE showed fission gas release from the bare kernels, but none from the TRISO particles. Two microscopy mounts, each containing two particles polished to the midplane have already been prepared. The proposed work aims to use SEM coupled with EDS and EBSD to characterize the microstructural differences, specifically focusing on fission product behavior, between the two configurations. Additionally, FIB tomography is proposed to examine the 3D structure of the gaseous fission products in the bubbles. With a proposed timeline of 2 months, the insight gained from this work will provide valuable data to support the development of mechanistic fuel models for UN fuel and provide some base for UN-TRISO fuel specifications.

Additional Info

Field	Value
Awarded Institution	Oak Ridge National Laboratory
DOI	10.46936/NSUF/60015367
Embargo End Date	2027-09-03
Facility Tech Lead	Kory Linton
NSUF Call	FY 2025 RTE 2nd Call
PI	Casey McKinney
PIE Facilities	Irradiated Fuels Examination Laboratory
Project Member	Dr. Jason Harp, Group Leader - Oak Ridge National Laboratory (https://orcid.org/0000-0002-5345-8440)
Project Member	Dr. Casey McKinney, Postdoctoral Research Associate - Oak Ridge National Laboratory (https://orcid.org/0000-0003-3538-3614)
Project Member	Dr. William Cureton, Research Scientist - Oak Ridge National Laboratory
Project Member	Dr Denise Adorno Lopes, Senior R&D Staff Member - Oak Ridge National Laboratory (https://orcid.org/0009-0002-3705-9877)
Project Type	RTE