Synthesis and Microwave Dielectric Properties of CaMg2Si3O9 Ceramics

CaMg2Si3O9 ceramics with low dielectric constant were obtained using the traditional solid-state reaction. Phase analysis, Raman spectroscopy, microstructure, and microwave dielectric properties of the CaMg2Si3O9 at different sintering temperatures were investigated. Only a single phase CaMg2Si3O9, which had the same monoclinic crystal structure as CaMgSi2O6 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 εr values of CaMg2Si3O9 ceramics initially increased and subsequently decreased as the sintering temperature increased. When the sintering was conducted at 1250 °C for 4 h, the CaMg2Si3O9 ceramics showed a maximum bulk density of 3.45 g/cm3 and enhanced microwave dielectric properties of εr = 7.61, Q × f = 41,998 GHz, and τf = − 49.8 ppm/°C.