Ag Out-surface Diffusion In Crystalline SiC With An Effective SiO2 Diffusion Barrier

Journal Article · Tue Sep 01 04:00:00 EDT 2015 · Journal of Nuclear Materials, 464:294-298

DOI:https://doi.org/10.1016/j.jnucmat.2015.05.001· OSTI ID:1208775

Xue, H.; Xiao, Haiyan Y.; Zhu, Zihua; Shutthanandan, V.; Snead, Lance L.; Boatner, Lynn A.; Weber, William J.; Zhang, Y.

For applications of tristructural isotropic (TRISO) fuel particles in high temperature reactors, release of radioactive Ag isotope (110mAg) through the SiC coating layer is a safety concern. To understand the diffusion mechanism, Ag ion implantations near the surface and in the bulk were performed by utilizing different ion energies and energy-degrader foils. High temperature annealing was carried out on the as-irradiated samples to study the possible out-surface diffusion. Before and after annealing, Rutherford backscattering spectrometry (RBS) and secondary ion mass spectrometry (SIMS) measurements were employed to obtain the elemental profiles of the implanted samples. The results suggest little migration of buried Ag in the bulk, and an out-diffusion of the implanted Ag in the near-surface region of single crystal SiC. It is also found that a SiO2 layer, which was formed during annealing, may serve as an effective barrier to reduce or prevent Ag out diffusion through the SiC coating layer.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1208775
• Report Number(s): PNNL-SA-111733; 47459; KP1704020
• Journal Information: Journal of Nuclear Materials, 464:294-298, Journal Name: Journal of Nuclear Materials, 464:294-298
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory