Dielectric and Piezoelectric Properties of Praseodymium Modified Lead Zirconate Titanate Ceramics

摘要

Praseodymium (Pr) modified lead zirconate titanate ceramics (Pb_(1-1.5x)Pr_x (Zr_yTi_(1-y)) O_3 with x = 0.02, 0.04, 0.06, 0.08 and y = 0.51, 0.52, 0.54, 0.56, 0.58, 0.60) were prepared by the high temperature solid-state reaction method. X-ray diffraction (XRD) results show that the morphotropic phase boundary (MPB) of Pb_(0.955)Pr_(0.03)(Zr_yTi_(1-y))O_3 (PPZT_1) is located in the area where the molar fraction of Zr is near 55%, when the molar fraction of Zr is 54% and the sintering temperature is 1240℃ with 1h curing time, the superior piezoelectric properties of compositions of PPZT_1 system were optimized, a set of d_(33) = 420 pC/N; ε~T_(33)/ε_0 = 2,000; T_c = 314℃; Q_m = 76; tanδ = 2% and k_p = 0.53. On the other hand, Pb_(1-1.5x)Pr_x(Zr_(0.54)Ti_(0.46))O_3 (PPZT_2) is far from MPB and their compositions are all in tetragonal phase.