Paper PI-22

Calculation of the Equilibrium Phase Diagram of Ca-Mgo-Al2O3-SiO2 Ceramic System by the ESTPHAD Method

Mende Tamás, Roósz András

University of Miskolc, Materials Science Institute, Department of Physical Metallurgy

H-3515 Miskolc, Egyetemváros, Hungary

In the metallurgical and materials engineering is important to know the phase transformation processes in metals and alloys induced by the temperature and concentration changes. This knowledge is simply shown by the measured phase diagrams. In this paper a method (called ESTPHAD) will be introduced, wich converts this phase diagrams into equations upon thermodynamic basis. This method used a regression wich assigns simple equations to the solidus, liquidus etc. curves. It could be easy to calculate the accurate values of the temperature or concentrations by this equations. The main advantage of this method (compared to others) the good accuracy and the low time necessity of the calculation.

The ESTPHAD method gives also a great aid in the field of ceramic materials. For this reason this paper shows the basics of the ESTPHAD method in the MgO rich corner of MgO-CaO-Al2O3-SiO2 quaternary system and its binaries and ternaries too. In Fig. 1. the measured and the calculated data are compared in case of binary MgO – CaO system.

Fig.1.