Variability of impurity doping in the modified Pb(Zr,Ti)O3 ceramics of type ABO3

The influence of sintering effects on microstructure, mechanical quality factor Q(m) and electromechanical coupling factor K Of 1 mol% Nb-doped lead zirconate titanate (PZT) piezoceramics with a composition Zr/Ti = 53/47 prepared by the conventional ceramic technology were investigated. Replacement of Ti+4 by Nb+5 in such perovskite type solid solutions was accomplished by the creation of cation vacancies. These created vacancies seemed to facilitate material transport and benefit from sintering. Calcined at 850degreesC/2 h and sintered at 1250degreesC/2 h, the PZT ceramics had the minimum value of Q(m) 50 and exhibited maximum electromechanical coupling factor kappa(p) 0.62 in accordance with the relationship between mechanical quality factor and electromechanical coupling factor. The measured P-E hysteresis loop illustrated that the remanent polarization (P-r) and coercive field (E-c) were 8.63 muC/cm(2) and 17.2 kV/cm, respectively. The fundamental resonance frequency was around 200 kHz, which was suitable for piezoelectric resonator and filter applications. (C) 2004 Elsevier Ltd. All rights reserved.