The Microwave Characteristics of Glass-BaTi₄O₉Ceramics

Microwave characteristics of BaTi 4 O 9 ceramics combined with different amounts of MgO–CaO–SiO 2 –Al 2 O 3 (MCAS) glass and sintered at different temperatures were examined. The temperature needed to densify the BaTi 4 O 9 dielectric is lowered with an increase of the content of MCAS glass. The densities and the dielectric constants of densified MCAS-BaTi 4 O 9 ceramics decrease with the an increasing amount of MCAS glass. The results of X-ray diffraction (XRD) patterns indicate that BaTi 4 O 9 and MCAS glass (cordierite phase) exist as two different phases. For BaTi 4 O 9 with 3 wt% addition of MCAS, the sintering temperature is lowered to 1200°C, and the ceramics have the optimum dielectric properties: Q =5720 ( Q × f =42050), ε r values=34.6, and τ f =14.2.