Effect of dysprosium substitution on the electrical properties of SrBi _4Ti _4O _(15) ceramics

摘要

The four-layer Aurivillius compound SrBi _(4x)Dy _xTi _4O _(15) (x=0.020.1) was synthesized by using a solid state sintering method. X-ray diffraction (XRD) analysis revealed that the dysprosium-substituted SrBi _4Ti _4O _(15) ceramics have a pure four-layer Aurivillius-type structure. The lattice parameters and densities were calculated with XRD studies. The experimental densities obtained were about 95% that of theoretical values. The effects of dysprosium oxide on the microstructure, ferroelectric, dielectric and piezoelectric properties of the ceramics were investigated. The dielectric constant of Dy-doped samples was found to decrease with increasing Dy content. At x=0.06, the piezoelectric charge coefficient (d _(33)) and the electromechanical coupling factor (k _p) were found to be maximum.