Structure and microwave dielectric properties of BaAl2−2x(CuSi)xSi2O8 ceramics

• Published in: Journal of materials science. Materials in electronics Vol. 31; no. 3; pp. 2591 - 2597
• Main Authors: Yan, Xinkan, Ding, Shihua, Zhang, Yun, Song, Tianxiu, Huang, Long, Zhang, Xiaoyun
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.02.2020; Springer Nature B.V
• Subjects: Bulk density; Celsian; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dielectric properties; Materials Science; Microstructure; Optical and Electronic Materials; Phase composition; Resonant frequencies; Sintering
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-019-02798-5

The sintering behavior, phase composition, microstructure and dielectric properties of BaAl 2−2 x (CuSi) x Si 2 O 8 ( x  = 0, 0.01, 0.015, 0.02, 0.04, 0.06, 0.08) ceramics prepared via solid-state reaction route were investigated. Deviation between theoretical and experimental permittivity of BaAl 2 Si 2 O 8 ceramics was discussed, and the theoretical and experimental temperature coefficient of resonant frequency ( τ f ) was also compared. The results showed that substituting (Cu 0.5 Si 0.5 ) 3+ for Al 3+ in matrix of hexacelsian could lower the sintering temperature from 1400 to 1200 °C and greatly promote the transformation of hexacelsian-to-celsian. And the single celsian phase was obtained for the compositions with x  ≥ 0.02. The bulk densities, microstructure and dielectric properties of BaAl 2−2 x (CuSi) x Si 2 O 8 ceramics were improved by doping a small quantity of (Cu 0.5 Si 0.5 ) 3+ ions in the BaAl 2 Si 2 O 8 . The BaAl 1.96 (CuSi) 0.02 Si 2 O 8 ceramics sintered at 1300 °C obtained good microwave dielectric properties: ε r  = 6.7, Q  ×  f  = 31,276 GHz, τ f  = − 17.17 × 10 −6 °C −1 .