Calculation of heterogeneous phase equilibria in the SiAlON system

Two available computer programs have been adapted for the calculation of phase equilibria in salt systems. Missing thermodynamic data have been estimated from known values and compared with experimental literature data. With one program the condensed quasibinaries Al2O3-AlN and SiO2-Si3N4 have been calculated. The other program was used to calculate heterogeneous phase equilibria in the SiAlON system. The results clearly show the importance of composition and partial pressures of the gas phase on the condensed equilibria.