Constituent binary subsystems Co-Cu, Co-Si and Cu-Si were described briefly, and their calculated phase diagrams were presented and invariant reactions of the liquid phase, as well. Thermodynamic parameters for Co-Si and Cu-Si systems were taken from the former own assessments and coefficients for binary system Co-Cu were accepted from the one of the most recent literature evaluations. Tdb file was then set up by means of binary formalism. Equilibrium calculations resulted in the parameters of all invariant reactions with liquid phase involved, and the Schei l reaction scheme was constructed as well. Graphical representation of the calculated liquidus surface was shown as the projection onto the G i b b s triangle plane.

On the basis of the earlier evaluation Bi-Cd system was critically assessed by means of CALPHAD method and using the most current thermochemical data for the constituent elements. The influence of various factors on the quality of data fitting was shown on the example of this systems.

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