Original paper(Vol.48 No.6 pp.566)

Preparation and electric properties of Pb (Sc sub 1 sub sub /2Nb sub 1 sub sub /2)O3 PbTiO3 PbZrO3 ceramics

Ohuchi Hiromu; Tsukamoto Shintaro; Yamanobe Yosuke; Morishita Toshinori

Abstract:Solid solution ceramics of the system xPb(Sc sub 1 sub sub /2Nb sub 1 sub sub /2)O3 yPbTiO3 zPbZrO3, where x equals 0 minus 0.4, y equals 0. 0.6, z equals 0 0.7, x plus y plus z equals 1, were prepared by the solid state reaction of powder materials. The density, dielectric and piezoelectric properties and crystal structures of sintered body were studied. The system was composed of three crystal phases at room temperature: the tetragonal, rhombohedral and orthorhombic. Sintering of the system xPb (Sc sub 1 sub sub /2 Nb sub 1 sub sub /2) O3 yPbTiO3 zPbZrO3 was much easier than that of each terminal compositions, and well sintered ceramics were obtained for the composition near the morphotropic transformation. Piezoelectric ceramics with high dielectric constants and high radial coupling coefficient, kr, and low mechanical quality factor were obtained for the compositions near the morphotropic transformation. Pb (Sc sub 1 sub sub /2Nb sub 1 sub sub /2) sub 0 sub .3Ti sub 0 sub . 4 4Zr sub 0 sub .2 sub 6O3 ceramics showed the high kr of 0.67.

Key Words:Pb(Sc1/2Nb1/2)O3-PbTiO3-PbZrO3 ceramics, morphotropic transformation, dielectric properties, piezoelectric properties, radial coupling coefficient