Effect of Doping Nb_2O_5 on Microstructure and Properties of Piezoelectric ceramics PSZT

摘要

To improve the electrical properties of PSZT piezoelectric ceramics, a ceramic powder Pb_(0.94)Sr_(0.06)(Zr_(0.52)Ti_(0.48))O_3 (PSZT) with Nb_2O_5 was designed. The power was prepared by solid state sintering. The surface structure of sample was characterized using SEM, and the crystal structure of the sample was examined by XRD. The capacitance and dielectric loss of sample was measured by Tonghui Electronics TH2618 capacitor tester. The result of microstructure and electrical properties show that Nb_2O_5 inhibit crystal growth when the contents of Nb_2O_5 is less than 0.5.wt%, but excessive Nb_2O_5 cause pyrochlore phase producing while the contents of Nb_2O_5 more than 0.5wt.%. The excellent piezoelectric properties are achieved in the ceramics with 0.5wt.% Nb_2O_5:ε_r=1504, tanδ=0.0065, d_(33)=336pC/N, kp=0.562.