Some algorithms of thermodynamic modeling by the theory of ideal associated solutions (TIAS) are provided. The thermodynamic properties of liquid alloys of the Al-C system are calculated using the TIAS and some experimental data. The analysis of own and literary data has allowed to establish the most reliable mixing enthalpies of binary boundary systems Al-Si(Ge, Sn, Pb), C-Si. This allowed to estimate the thermodynamic properties of ternary alloys of the Al-C-Si(Ge, Sn, Pb) systems by Kohler equation.

Are critically parsed and the thermodynamic properties of alloys of three-component systems Si - Al - Me are generalized. For obtaining the indicated systems in all a concentration interval their simulation from the data for double systems on an equation Bonnier – Cabo is made.

There are the results of investigation of deoxidizing ability of 4d–metals in Fe–Ni–O melting systems (invars) carried out by calorimetry method in isoparabolic calorimeter at 1873 K.

The partial and integral mixing enthalpies of liquid Ni - S and Ni - S - Me alloys at 1870 K are determined by calorimetry. The first partial mixing enthalpy of sulfur in nickel is 130 +/- 20 kJ/mole, which agrees with literature data. The activity of nickel in the range 0.5 < x(Ni) < 1 is calculated from the Ni - S phase diagram, with extrapolation of the results over the whole concentration range; the activity of sulfur is calculated from the Gibbs - Duhem equation. The activity of sulfur is characterized by very large negative deviations from Raoult's law. The partial solution enthalpies of a number of metals in Ni - S melts are determined. According to the results, the exothermal effect is greatest for the solution of La and Ce, which may be used as strong sulfur-removal agents.

The thermochemical properties of Fe-Hf (1870 K) and Ni-Hf (1877 K) melts were studied by calorimetry. The melts were shown to feature strong interatomic interactions, with <(Delta H)over bar>(Hf(Fe)) = -80 +/- 5 kJ/mol and <(Delta H)over bar>(Hf(Ni)) = -137 +/- 8 kJ/mol. These findings are in line with phase-diagram data, according to which the Fe-Hf and Ni-Hf systems each contain a few intermetallic compounds. The thermochemical properties of Fe-IVb and Ni-IVb melts are compared. The iron-based melts are characterized by an insignificant increase in heat effects in going from titanium to zirconium or hafnium. In the Ni-IVb systems, the energy of interatomic interactions rises in the sequence Ni-Hf --> Ni-Ti --> Ni-Zr.