The microwave dielectric properties of CaxSr1−xBi2Nb2O9 (0.0 ≤ x ≤ 1.0) ceramics

Abstract

To improve the microwave dielectric properties of SrBi2Nb2O9 ceramics, the Ca element was selected as the substitute for Sr site. The CaxSr1−xBi2Nb2O9 ceramics were prepared by the conventional solid-state ceramic route. The crystal structure, microstructural evolution and microwave dielectric properties of CaxSr1−xBi2Nb2O9 (x = 0.0, 0.3, 0.6 and 1.0) were investigated. With the content of Ca2+ ions increasing, the dielectric constant er decreased from 145 to 98 and Q × f value increased from 167 to 672 GHz, respectively. Increasing sintering temperature can effectively promote the dielectric properties of CaxSr1−xBi2Nb2O9 ceramics. The optimal microwave dielectric property of er = 98, Q × f = 672 GHz was obtained for the CaBi2Nb2O9 ceramic sintered at 1050 °C for 5 h. The relatively low sintering temperature and high dielectric properties in microwave range would make CaxSr1−xBi2Nb2O9 ceramics promising for application in electronics.