Densification, microstructural evolution, and dielectric properties of CaTiO3-LaGaO3 microwave ceramics

The relations among the densification, microstructural evolution, and microwave dielectric properties of the (1-x)CaTiO3-xLaGaO(3) ceramics with x=0.34 and 0.36 were investigated in this study. The results indicated that (1-x)CaTiO3-LaGaO3 ceramics can be densified at 1300 degrees C with at least 97% of the theoretical value. The ceramics reported an orthorhombic perovskite structure, and no other detectable phases were found. Both epsilon(r) and Qxf values can be improved by slowing the cooling rate during sintering. The epsilon(r) and Qxf values of the 0.64CaTiO(3)-0.361.aGaO(3) ceramics at cooling rates of > 10 degrees C/min and 0.1 degrees C/min are 48.1 and 27,500 and 48.7 and 38,000, respectively. The higher densification obtained at a slower cooling rate plays an important role in improving the microwave dielectric properties. (C) 2011 Elsevier Ltd. All rights reserved.