Effect of ZrO2 Doping on the Microwave Dielectric Properties of Ba(Mg1/3Nb2/3)O3 Ceramics

The microwave dielectric properties of Ba(Mg1/3Nb2/3)O-3 ceramics with x (x = 0-10) wt.% ZrO2 (BMZN) were investigated by the solid-state reaction technique. X-ray diffraction (XRD) analysis suggested that there were two phases: the main crystalline phase Ba(Mg1/3Nb2/3)O-3(BMN) and a secondary phase Ba5Nb4O15. Meanwhile, the Zr ions entered the B site of BMN and disturbed the 1:2 ordering. Scanning electron microscopy (SEM) analysis demonstrated that Zr4+ could promote the grain growth obviously. The addition of Zr4+ had a huge and positive influence on the Q x f value, for example, the sample with x = 8 had the highest Q x f value of 106,410 GHz. The BMZN ceramics with x = 8 sintered at 1400A degrees C for 5 h had excellent microwave dielectric properties: epsilon (r) = 32.9, Q x f = 106,410 GHz (f = 8 GHz) and tau(f) = +0.7 ppm/A degrees C.