Formation kinetics and equilibrium thermodynamics study on the Bi₂O₃-TiO₂ system for synthesis of the bismuth titanate ceramics

Formation kinetics and equilibrium thermodynamics are fundamental knowledge for predicting microstructure and properties during materials processing and utilization. This work prepared high purity Bi₁₂TiO₂₀, Bi₄Ti₃O₁₂ and Bi₂Ti₄O₁₁ compounds and characterized these compounds by in-suit X-ray diffraction, scanning electron microscope, energy dispersive spectrometer as well as calorimetry. Based on the experimental data obtained in this work and the literature, a thermodynamic description of the Bi₂O₃–TiO₂ system was carried out, a thermodynamic database as well as the calculated phase diagram of the system was provided. The discrepancy between the present calculation with the experimental data were discussed, the formation kinetics of the compounds was explained and the bismuth titanate ceramics with tailored structure and specific physical properties were sintered.