Preparation, sintering, and microstructures of strontium barium bismuth tantalate layered perovskite ceramics

• Published in: Journal of materials science 2004-05, Vol.39 (9), p.3079-3083
• Main Authors: LU, Chung-Hsin, BAI, Jia-Hau, HUNG CHEN
• Format: Article
• Language: English
• Subjects: Applied sciences; Barium; Bismuth; Building materials. Ceramics. Glasses; Ceramic industries; Ceramic powders; Ceramics; Chemical industry and chemicals; Electrotechnical and electronic ceramics; Exact sciences and technology; Grains; Lattice parameters; Materials science; Morphology; Perovskite structure; Perovskites; Plates (structural members); Preferred orientation; Rapid prototyping; Sinterability; Sintering (powder metallurgy); Solid solutions; Technical ceramics
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1023/B:JMSC.0000025835.22825.5c

The solid solutions of Ba-doped SrBi2Ta2O9 layered perovskite ceramic powders have been successfully prepared via a two-step process using BiTaO4 as a precursor. The lattice constants of the solid solutions monotonically increase with increasing barium-ion content. The sinterability of (Sr1−xBax)Bi2Ta2O9 powders is significantly improved by increasing the barium-ion content. When the specimens with high barium-ion contents are sintered at 1100°C, they thermally decompose to form rod-like grains and the matrix expands, leading to a lower density. The addition of barium ions to SrBi2Ta2O9 also results in significant variation in the morphology of the sintered specimens and the occurrence of c-axis preferred orientation which is ascribed to the anisotropic growth of plate-like grains. The precise control of the barium-ion content as well as the sintering conditions is critical for obtaining densified barium-ion doped SrBi2Ta2O9 ceramics with a pure, layered perovskite structure.