The Reaction Sequence and Dielectric Properties of BaAl₂Ti₅O₁₄ Ceramics

Xiaogang Yao, Wei Chen, Lan Luo

Shanghai Institute of Ceramics Chinese Academy of Science.

DOI: 10.4236/ampc.2012.24B008                

Abstract

To investigate the correct reaction sequence of BaO-Al₂O₃-5TiO₂ system, powders calcined at different temperatures are analyzed by x-ray diffraction. The results show that the source phase BaCO₃ decomposes below 800°C, TiO₂ and Al₂O₃ start to consume at 900 and 1100°C, respectively. BaTi₄O₉ phase appears at 1000°C while BaAl₂Ti₅O₁₄ phase starts to reveal at 1200°C. As the temperature increases, the density, dielectric constant and quality factor of the BaAl₂Ti₅O₁₄ ceramic increase and keep unchanged at 1350°C. The dielectric properties of BaAl₂Ti₅O₁₄ ceramic sintered at 1350°C for 3h are: ε_r=35.8, Q×f=5130GHz, τ_f=-6.8ppm/°C.

Keywords

Reaction Sequence; BaAl₂Ti₅O₁₄; Ceramics; Dielectric Properties

Conflicts of Interest

The authors declare no conflicts of interest.

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