摘要

The results of predicting thermodynamic properties in the full composition range of Ti-Al binary melts in a temperature range from 1973 to 2273 K were obtained by coupling with the developed thermodynamic model for calculating mass action concentration N-i of structural units in Ti-Al system based on the atom and molecule coexistence theory (AMCT). Temperature dependence of the activity coefficients of Ti and Al in natural logarithmic form in the infinitely dilute solution (0<x(Ti)<0.01) of Ti-Al binary melts was also determined from the calculated activity coefficients of Ti and Al at temperatures of 1973, 2073, 2173, and 2273 K. The standard molar Gibbs free energy change of dissolving pure liquid element i(l) for forming 1% (mass fraction) element i in Ti-Al binary melts further was deduced. With the aid of this model, meanwhile, the determined excess thermodynamic properties, such as the excess molar mixing Gibbs free energy/entropy/enthalpy were also calculated.