Piezoelectric Property and Strain Behavior of Pb(Yb_(0.5)Nb_(0.5))O_3-PbHfO_3-PbTiO_3 Polycrystalline Ceramics

摘要

(1-x)Pb(Hf_(1-y)Ti_x)O_3-xPb(Yb_(0.5)Nb_(0.5))O_3 (x = 0.10-0.44, y = 0.55-0.80) ceramics were fabricated. The morphotropic phase boundary (MPB) of the ternary system was determined by X-ray powder diffraction. The optimum dielectric and piezoelectric properties were achieved in 0.8Pb(Hf_(0.4)Ti_(0.6))O_3-0.2Pb (Yb_(0.5)Nb_(0.5))O_3 ceramics with MPB composition, where the dielectric permittivity ε_r, piezoelectric coefficient d_(33), planar electromechanical coupling k_p, and Curie temperature T_c were found to be on the order of 1930,480 pC/N, 62%, and 360℃, respectively. The unipolar strain behavior was evaluated as a function of applied electric field up to 50 kV/cm to investigate the strain nonlinearity and domain wall motion under large drive field, where the high field piezoelectric d_(33) was found to be 620 pm/V for 0.82Pb(Hf_(0.4)Ti_(0.6))O_3-0.18Pb(Yb_(0.5)Nb_(0.5))O_3. In addition, Rayleigh analysis was carried out to study the extrinsic contribution, where the value was found to be in the range 2%-18%.