Determining the tensile strength of fuel surrogate TRISO-coated particle buffer, IPyC, and buffer-IPyC interlayer regions

Journal Article · 25 May 2023 · Journal of Nuclear Materials

DOI: https://doi.org/10.1016/j.jnucmat.2023.154540 · OSTI ID:2000529

Mauseth, Tanner  ^[1]; Dunzik-Gougar, Mary Lou ^[1]; Meher, Subhashish ^[2]; van Rooyen, Isabella Johanna  ^[3]

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1. Idaho State University, Pocatello, ID (United States)
2. Idaho National Laboratory (INL), Idaho Falls, ID (United States)
3. Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

A novel micro tensile sample fabrication technique for determining the tensile strength of the buffer, IPyC, and buffer -IPyC interlayer regions of surrogate (ZrO2) TRISO fuel particle layers was refined and implemented. Copper micro tensile samples served as baseline materials to verify the methods used. Tensile tests performed in this study, while limited in number, were analyzed using standard and Weibull statistics. As expected, the buffer layer was weakest, with an average ultimate tensile strength of 138.70 MPa, and the IPyC layer samples, were strongest, with an average ultimate tensile strength of 189.74 MPa. In the buffer -IPyC interface samples, all breaks occurred in the buffer region, though the average ultimate tensile strength of the samples, 159.80 MPa, was between the pure buffer and IPyC samples. These results suggest the interlayer region has unique properties, perhaps associated with pyrocarbon infiltration into the buffer layer during particle coating. All interlayer samples fractured within the buffer side; however, the stress strain behavior of some of these samples resembled the behavior of the IPyC layer samples. Here, the buffer and IPyC layer strengths had a normal distribution under Weibull analysis, while the interlayer region had a Rayleigh distribution. Further testing is needed to clarify both the standard and Weibull statistical results

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE)
• Grant/Contract Number: AC05-76RL01830
• OSTI ID: 2000529
• Alternate ID(s): OSTI ID: 2000099
• Report Number(s): PNNL-SA--181513
• Journal Information: Journal of Nuclear Materials, Journal Name: Journal of Nuclear Materials Vol. 583; ISSN 0022-3115
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English