Sintering behavior and dielectric properties of Al2O3 ceramics with CaMgSi2O6 addition

Al2O3–CaMgSi2O6 ceramics with different amount of CaMgSi2O6 additions were prepared by a conventional solid-state method, and the effects of CaMgSi2O6 addition on the sintering behavior and dielectric properties of Al2O3 ceramics have been investigated. CaMgSi2O6 was used as a liquid sintering aid to effectively lower the sintering temperature of Al2O3 ceramics and its addition resulted in the presence of CaAl2Si2O8 and MgAl2O4 phases. However, the CaMgSi2O6 addition deteriorated the dielectric properties of Al2O3–CaMgSi2O6 ceramics because of the higher dielectric loss of the derived CaAl2Si2O8 and MgAl2O4 compared with that of Al2O3 ceramics. After sintered at 1450°C, the Al2O3–CaMgSi2O6 ceramic with 10 wt % CaMgSi2O6 addition possessed dielectric properties of εr = 9.83, tan δ = 1.5 × 10−4 (1 MHz) and Q × f = 20,425 GHz (f0 = 12 GHz).