the crystal structure was analyzed using an X-ray diffractometer. and the surface morphology was examined with a field emission scanning electron microscope.Electrical measurements were carried out after screen-printing Ag paste on both sides of a disk-shaped specimen and subsequent firing at 700 for 30 min.The electric-field-induced strain measurement was carried out using a linear variable differential transducer.The piezoelectric constant d33 was determined using a Berlin-court d33-meter after poling samples under an electric field of 5kV/mm at 80 for 15 min.The dielectric constant,loss tangent,planar piezoelectric coupling coefficient and mechanical quality factor of poled specimens were characterized with an impedance analyzer on the basis of IEEE standards.