Thermodynamic investigations of fuel-cladding chemical interaction in U-5Fs and U-10Zr metallic fuels with the TAF-ID

Fuel-Cladding Chemical Interaction (FCCI) in metallic nuclear fuels is a key phenomenon that limits the maximum burn-up and operating power as it can cause premature failure of fuel cladding. Therefore, being able to accurately predict interactions fuel-cladding system by means thermodynamic calculations contributes our understanding how mitigate this mechanism. In order test capabilities Thermodynamic Advanced Fuels – International Database (TAF-ID) these interactions, have been performed on two irradiated fuels: U-5Fs SS316 cladding U-10Zr HT9 cladding, for which experimental observations are available literature. TAF-ID allowed confirmation some phases were observed during characterizations identification unknown ones: Particularly fuel, primary Fe-rich predicted: (i) FeU6, extends up 120 ?m into (ii) UFe2 with >30 wt.% Fe, likely be layer experimentally adjacent side. Also, minor observed, such U-Mo, U-Ru, lanthanoid-noble metals (Nd,Ce-Pd), predicted stable. As several U-Fe-Zr (e.g., UFe2, ?-FeUZr), Fe-(Ce,Nd) Fe17Ln2), FCC phase consisting Ce, Nd, La, Y, Sr. These excellent agreement observations.