Synthesis and diffused phase transition of Ba0.7Sr0.3TiO3 ceramics by a reaction-sintering process

Ba0.7Sr0.3TiO3 (BST) ceramics prepared by a reaction-sintering process were investigated. BST ceramics could be obtained after 2–6 h sintering at 1330–1370 °C without any calcination involved. BST with density 5.68 g/cm3 (99.8% of the theoretic value) was obtained at 1350 °C for 6 h sintering. Grains of 2–15 μm were formed after 2–6 h sintering at 1330–1370 °C. A diffused ferroelectric–paraelectric transition was observed in pellets sintered at 1330 °C for 2 h and disappeared at a longer soak time or a higher sintering temperature.