Synthesis and microwave dielectric properties of CaMg2Si3O9 ceramics

• Published in: Journal of materials science. Materials in electronics 2020-12, Vol.31 (23), p.21583-21590
• Main Authors: Gao, Yan, Zheng, Yong, Lu, Xuepeng, Dong, Zuowei, Ke, Zheng
• Format: Article
• Language: English
• Subjects: Bulk density; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Crystal structure; Dielectric properties; Grain size; Grain size distribution; Materials Science; Optical and Electronic Materials; Raman spectroscopy; Sintering
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-020-04671-2

CaMg 2 Si 3 O 9 ceramics with low dielectric constant were obtained using the traditional solid-state reaction. Phase analysis, Raman spectroscopy, microstructure, and microwave dielectric properties of the CaMg 2 Si 3 O 9 at different sintering temperatures were investigated. Only a single phase CaMg 2 Si 3 O 9 , which had the same monoclinic crystal structure as CaMgSi 2 O 6 with a space group of C2/c, was formed in the sintered bodies and no second phases existed in ceramics when sintered at different temperatures. With sintering temperatures from 1200 to 1300 °C, the average grain size of ceramics continuously increased, and the grain size distribution became uniform. The density, Q  ×  f , and the ε r values of CaMg 2 Si 3 O 9 ceramics initially increased and subsequently decreased as the sintering temperature increased. When the sintering was conducted at 1250 °C for 4 h, the CaMg 2 Si 3 O 9 ceramics showed a maximum bulk density of 3.45 g/cm 3 and enhanced microwave dielectric properties of ε r  = 7.61, Q  ×  f  = 41,998 GHz, and τ f = − 49.8 ppm/°C.