Strontium doping effects on the characteristics of Sm-modified PbTiO ₃ ceramics

In this paper, Sr dopants are introduced in the Sm-modified lead titanate (PbTiO₃) ceramic systems with a composition of (Pb_0.88-x Sr_xSm_0.08)(Ti_0.98Mn_0.02)O ₃; x = 0.05-0.25 using conventional mixed-oxide method. Dielectric and piezoelectric properties of these doped ceramics were measured at room temperature. Micro structural and compositional analyses have been carried out using scanning electron microscope (SEM) and X-ray diffraction (XRD). The Curie point versus the amount of Sr composition was also investigated. Surface acoustic wave (SAW) properties, including phase velocity and electromechanical coupling coefficient, were measured. The experiments successfully showed that Sr additive is helpful to obtain higher phase velocity and high electromechanical coupling coefficient. The SAW properties of our samples (V_p, k²) are better than the commercially-made PZT and PT samples.