A mathematical model for the calculation of TiAl alloy evaporation and deposition was developed. The activity coefficients of the elements represent the interaction between the components in the liquid pool. It is found that the main parameters affecting the evaporation rate include the activity coefficients and saturation vapor pressures of the elements. Experimental data are coincided with calculated data well. The results show that TiAl alloy can be deposited using the so-called single-crucible consisting of a water-cooled copper crucible with the base material being fed continuously through the bottom of the crucible.