Fuel-Cladding Interaction Between U-Pu-Zr Fuel and Fe

Abstract

This work investigates fuel-cladding chemical interaction (FCCI) between U-25Pu-14Zr (in wt pct) fuel and pure Fe at elevated temperatures, understanding of which is critical for evaluation of the fuel performance. Phases and microstructure formed in the quaternary uranium-plutonium-zirconium-iron (U-Pu-Zr-Fe) system were characterized using the transmission electron microscopy technique. Phases formed within the FCCI layer were identified using selective area electron diffraction (SAED) analysis as Fe2U (Fd- m), Fe2Zr (Fd-3m), α-U (Cmcm), Fe2Pu (Fd-3m), β-Pu (C12/m1), and β-Zr (Im-3m).