Silver diffusion in coated fuel particles

An innovative method has been developed to trap silver (Ag) between two layers of silicon carbide (SiC) produced by chemical vapor deposition at 1300°C. The study has shown for the first time that silver diffuses through intact SiC in tristructural isotropic-coated particles. We also refute some speculations reported in previous studies by showing that silver can diffuse in stoichiometric SiC and that it is the differences in SiC microstructure that play a fundamental role in the diffusion process rather than the formation of nanocracks due to a mechanical process. Our results stress the importance of the microstructure inherent to the SiC produced by fluidized bed chemical vapor deposition on Ag diffusion.