Microwave properties of B2O3-doped Nd(Mg1/2Ti1/2)O3-CaTiO3 dielectric resonators at microwave frequency

The effects of B2O3 addition on the microwave dielectric properties and the microstructures of (1-x)CaTiO3-xNd(Mg1/2Ti1/2)O-3 ceramics prepared by conventional solid-state routes have been investigated. Doping with 0.5 wt.% B2O3 can effectively promote the densification and the microwave dielectric properties of (1-x)CaTiO3-xNd(Mg1/2Ti1/2)O-3. It is found that CaTiO3-Nd(Mg1/2Ti1/2)O-3 ceramics can be sintered at 1300 degrees C due to the liquid phase effect of a B2O3 addition observed by scanning electronic microscopy (SEM). The system forms a solid solution throughout the entire compositional range. The dielectric constant decreases from 143 to 27 as x varies from 0.1 to 1.0. In the (1-x)CaTiO3-xNd(Mg1/2Ti1/2)O-3 system, the microwave dielectric properties can be effectively controlled by varying the x value. The microwave dielectric properties indicate the possibility of a phase transformation for x between 0.3 and 0.5. (c) 2005 Elsevier B.V. All rights reserved.