Preparation and ferroelectric properties of MnO₂ doped BaTi ₂O₅ ceramics by spark plasma sintering from the solid-state-calcined powder

Dense BaTi₂O₅ are fabricated from the conventional calcined powder by using spark plasma sintering and by adding MnO₂ as a dopant. The effects of the sintering temperature and the amount of MnO ₂ on the phase purity are symmetrically investigated. A pure BaTi₂O₅ phase is obtained under a condition with the sintering temperature of 1,055 C and the amount of MnO₂ doping of 0.2 wt% from the conventional powder calcined at 950 C. The relative density of that ceramics is 98 %. The temperature dependence of dielectric property shows the Curie temperature (T _c) of 446 C with the peak value of 450. Besides, the ceramics polarization of 0.63 μC/cm² and the coercive field of 2.0 kV/cm at room temperature, respectively.