Thermodynamic modeling of the CaO-SiO2-M2O (M=K,Na) systems

The aim of the present study is the CALPHAD modeling of the systems CaO-SiO2-M2O (M=K,Na) based on a careful review of the available literature data - phase diagram and thermodynamics - as well as own experiments. The heat capacities (Cp) of three compounds, CaSiO3, K2Ca2Si2O7 and K 8CaSi10O25 (determined using drop calorimetry), were included in the optimization of the ternary phase diagram CaO-SiO2-K2O.