THERMODYNAMICS OF GAS DISSOLUTION IN LIQUID-METALS WITH EXTENSIVE SOLUBILITY - THE U(L)-N, ZR(L)-O, AND TH(L)-O SYSTEMS

The pressure-composition-temperature (p-C-T) relationships of the syst ems U(L)-N, Zr(L)-O, and Th(L)-O are derived using thermodynamic const raints and a modified form of Sievert's law. The results are used to e valuate the thermodynamic functions of each system: The integral Gibbs enthalpy of formation of UN and the Gibbs energy of solution of nitro gen in liquid uranium are determined. Inconsistency in the literature concerning the Th(L)-O system is resolved. The equilibrium oxygen pres sure in the two-phase alpha Th(L)/sigma ThOC region is reassessed and the corresponding Gibbs energy of solution is determined.