Sintering Behavior and Microwave Dielectric Properties of MgO-2B 2 O 3 - Xwt %H 3 BO 3 - Ywt %BCB Ceramics

The bulk density, sintering behavior and microwave dielectric properties of MgO-2B 2 O 3 series ceramics synthesized by solid-state reaction method were systematically studied in this paper. X-ray diffraction and microstructural analysis revealed that the as-prepared MgO-2B 2 O 3 ceramics possessed a single-phase structure with rod-like morphology. Through the investigation of the effects of different dosages of H 3 BO 3 and BCB on bulk density, sintering behavior and microwave dielectric properties of MgO-2B 2 O 3 ceramics, the optimum sintering temperature was obtained at an addition of 30 wt %H 3 BO 3 and 8 wt %BCB and the sintering temperature was reduced to 825 o C. The addition of 40 wt %H 3 BO 3 and 4 wt %BCB increased the quality factor Q×f , permittivity ε r and temperature coefficient of resonance frequency τ f of MgO-2B 2 O 3 to 44,306 GHz, 5.1 and -32 ppm/ o C, respectively, meeting the criteria of low-temperature co-fired ceramics.