Specific Heat and Thermal Expansion of BaTiO₃

Abstract

The specific heat and thermal expansion of barium titanate ceramics were measured between room temperature and 250°C., and their anomalies were confirmed. The specific heat, that was measured by Sykes' method showed a λ-type anomaly at the Curie temperature, but the magnitude of the anomaly at the peak was considerably small, amounting to only 0.005∼0.015 cal/gr. °C. We measured the thermal expansion with an optical dilatometer, and observed a contraction in the transition region. The thermal expansion coefficient showed a negative peak at the Curie temperature. The specific heat and thermal expansion vs. temperature curves and the positions of their peaks varied slightly for different samples by the condition of their preparation.