ACTIVITY COEFFICIENT OF NITROGEN IN BINARY LIQUID METAL ALLOYS.

Literature data for the limiting thermodynamic properties of nitrogen in liquid Fe, Co, Ni, and Cr, as well as in the six binary alloys consisting of two of the above elements, are critically evaluated. The ternary data are evaluated in terms of C. Wagner's model for quasi-interstitial liquid alloys, and values of the Wagner parameter h are obtained for each system. The correlation formulated by T. Chiang and Y. A. Chang between the Wagner parameter h and the relevant binary thermodynamic properties for oxygen in binary alloys has been found to be equally valid for nitrogen in binary alloys. From this correlation, a value of h may be predicted in the absence of any ternary experimental data. Utilizing the Wagner model and the value of h obtained for each system, values for the first-order and second-order Gibbs energy interaction parameters are derived.