Thermodynamic properties of vanadium nitride

Nitrogen-vanadium mononitride equilibrium in homogeneity region of the latter and in the VN x-V 2N y heterogeneous system has been studied by thermogravimetric method at nitrogen pressures 0.5...1000 hPа and temperatures 1573...1923 K. Dependence of equilibrium nitrogen pressure on composition and temperature was obtained using a thermodynamic model based on C. Wagner’s method of interaction parameters. Standard Gibbs formation energies of stoichiometric nitride at 1500...2000 K were calculated and an equation for formation energy of a nonstoichiometric nitride of given composition is presented.