Abstract
The article presents a non-model algorithm for calculating the fusibility diagrams of multicomponent systems exclusively from data on the fusibility diagrams of binary subsystems. The first geometric calculation algorithm is based on solving systems of linear equations of liquidus isotherms. The second, thermodynamic calculation algorithm requires only the coordinates of the binary eutectic. The application of both algorithms is demonstrated by the example of fusibility diagrams of ternary quasi-simple salt systems with a common cation and a common anion. There is a convincing agreement between the calculation results the results of the non-model calculation with the available experimental literature data. The proof of the fact that all non-invariant points of various quasi-simple ternary systems (with two identical and one different component) belong to one mono-variant curve is given. Examples of calculations of these mono-variant curves are given and convincing agreement of the non-model calculation with experimental data is demonstrated. A system of transcendental equations has been compiled for calculating the coordinates of ternary eutectic.