Re‐experimental determination phase equilibria in the CaO–SiO ₂ –TiO ₂ system at 1300–1400°C in air

Abstract The phase equilibria of the CaO–SiO 2 –TiO 2 ternary system were experimentally investigated at 1300 and 1400°C in air using high‐temperature equilibration followed by quenching, combined with phase identification via x‐ray diffraction and electron probe microanalysis. Based on the identified phase assemblages, isothermal sections at both temperatures were constructed. Comparisons with the calculated diagrams from the FactSage thermodynamic software and previous reported data revealed notable discrepancies, particularly in the SiO 2 ‐rich region and the extent of rutile primary phase field. These findings provide reliable experimental constraints for thermodynamic model optimization and offer a solid foundation for the design and performance tuning of Ti‐bearing oxide ceramics.