ABSTRACT
The effects of CaTiO3 addition on microstructure and microwave dielectric properties of α-CaSiO3-6 wt% SiO2 have been investigated. The X-Ray Diffraction (XRD) patterns results indicate that samples exhibit a three-phase system, which has a wollastonite-structured α-CaSiO3 primary phase associated with SiO2 and CaTiO3 minor phase. It was observed that the average grain size increased with the increasing addition of CaTiO3 by Scanning Electron Microscope (SEM). The τ f value is strongly correlated to the compositions and can be controlled through the compositional ratio. The α-CaSiO3-6 wt% SiO2 ceramics containing 2.5 wt% of CaTiO3 sintered at 1350°C showed excellent microwave dielectric properties: an ε r value of 7.86, a quality factor Q × f value of 21,035 GHz, and a τ f value of 0.59 ppm/°C.
