High performance X8R dielectric ceramics were prepared by dopingBi2O3 to BaTiO3-based ceramics.The effect of small amounts（≤1.2 mol%） ofBi2O3 additive on the microstructure and dielectric properties of BaTiO3-based...High performance X8R dielectric ceramics were prepared by dopingBi2O3 to BaTiO3-based ceramics.The effect of small amounts（≤1.2 mol%） ofBi2O3 additive on the microstructure and dielectric properties of BaTiO3-based ceramics have been investigated.The Bi2O3 ,acting as a sintering additive,can effectively lower the sintering temperature of BaTiO3-based ceramics from 1300 to 1130 °C.The bulk density of BaTiO3-based ceramics increased and reached the maximum value with increasingBi2O3 content.The dielectric constant increased with increasingBi2O3 until it reached the maximum value with 0.8 mol%Bi2O3 additive,and the dielectric loss decreased with increasingBi2O3 content.Optimal dielectric properties of ε=2470,tanδ=0.011 and △ε/ε 25 ≤±9%（-55-150 °C） were obtained for the BaTiO3-based ceramics doped with 0.8 mol%Bi2O3 sintered at 1130 °C for 6 h.展开更多
Titania （TiO2） and barium titanate （BaTiO3） were synthesized using three different dicarboxylates, which included oxalate, malate and tartarate. These powders were characterized by X-ray powder diffraction, scanni...Titania （TiO2） and barium titanate （BaTiO3） were synthesized using three different dicarboxylates, which included oxalate, malate and tartarate. These powders were characterized by X-ray powder diffraction, scanning electron micrographs, BET specific surface area and particle size distribution. Their properties depended to a great extent on the nature of the precursor. The titania and barium titanate powders obtained from the tartarate precursor were found to be good for slip casting. Slips of these oxides with different solids contents were prepared at different pH values using both distilled water and ethanol as the dispersing agent and also with and without deflocculant. The theological behaviors of the suspensions were then determined, and the slip, green and sedimentation bulk densities were measured. The minimum viscosities were observed at pH 8.2 for the TiO2-water and pH 10.2 for the BaTiO3-water system.展开更多
基金supported by the Tianjin Natural Science Foundation, China (Grant No. 06YFJMJC01000)
文摘High performance X8R dielectric ceramics were prepared by dopingBi2O3 to BaTiO3-based ceramics.The effect of small amounts（≤1.2 mol%） ofBi2O3 additive on the microstructure and dielectric properties of BaTiO3-based ceramics have been investigated.The Bi2O3 ,acting as a sintering additive,can effectively lower the sintering temperature of BaTiO3-based ceramics from 1300 to 1130 °C.The bulk density of BaTiO3-based ceramics increased and reached the maximum value with increasingBi2O3 content.The dielectric constant increased with increasingBi2O3 until it reached the maximum value with 0.8 mol%Bi2O3 additive,and the dielectric loss decreased with increasingBi2O3 content.Optimal dielectric properties of ε=2470,tanδ=0.011 and △ε/ε 25 ≤±9%（-55-150 °C） were obtained for the BaTiO3-based ceramics doped with 0.8 mol%Bi2O3 sintered at 1130 °C for 6 h.
文摘Titania （TiO2） and barium titanate （BaTiO3） were synthesized using three different dicarboxylates, which included oxalate, malate and tartarate. These powders were characterized by X-ray powder diffraction, scanning electron micrographs, BET specific surface area and particle size distribution. Their properties depended to a great extent on the nature of the precursor. The titania and barium titanate powders obtained from the tartarate precursor were found to be good for slip casting. Slips of these oxides with different solids contents were prepared at different pH values using both distilled water and ethanol as the dispersing agent and also with and without deflocculant. The theological behaviors of the suspensions were then determined, and the slip, green and sedimentation bulk densities were measured. The minimum viscosities were observed at pH 8.2 for the TiO2-water and pH 10.2 for the BaTiO3-water system.
