Effects of calcium on the phase transition and the dielectric properties of Sm-modified PbTiO3 ceramics

Abstract (Pb 0.85 Sm 0.1 )(Ti 0.98 Mn 0.02 )O 3 ceramics exhibits exceptionally large electromechnical anisotropy. Their properties allow them to be used for high-frequency applications such as SAW devices and piezoelectric transformers. Our previous studies on (Pb 0.88− x Ca x Sm 0.02 )(Ti 0.98 Mn 0.02 )O 3 ( x =0.11−0.17) ceramics demonstrated that the Ca and Sm additives not only reduce the lattice anisotropy, but also maintain good dielectric and anisotropic properties of Sm and Ca-modified PbTiO 3 ceramics. This study investigates the effect of calcium on the phase transition and dielectric properties of this system. X-ray diffraction, Raman scattering and DSC methods are used to elucidate the doping effect of (Pb 0.88− x Ca x Sm 0.02 )(Ti 0.98 Mn 0.02 )O 3 . The X-ray results show that the c / a ratio decreases as the amount of Ca dopant increases. The DSC result indicates that the transition temperature of the F–P transition of Ca-doped PbTiO 3 decreases as the content x increases.