Thermodynamics of the interactions between liquid breeders and ceramic coating materials

The thermodynamic stabilities (Δ ri G) of various ceramics towards Pb Li alloys have been evaluated as a function of temperature, lithium composition and, for lithium, non-metal solute concentration. For non-metal saturated alloys, both increasing temperature and decreasing lithium composition (from lithium to Pb -17Li) lead to increased stability (more positive Δ r G values). Reducing non-metal solute concentration in lithium by cold trapping leads to decreased stability. Of the ceramics presently being assessed as coating materials, AlN, TiN, TiC, Y 2O 3 and CaO are stable in reactor grade Pb 17Li and reactor grade lithium, β-SiC, Al 2O 3, SiO 2 and MgO are stable in Pb 17Li but not lithium and Cr 2O 3 is unstable in both breeders.