Materials Research Bulletin, Vol.44, No.3, 638-643, 2009
Effect of ZnO addition on the sintering and electrical properties of (Mn,W)-doped PZT-PMS-PZN ceramics
The effect of ZnO addition on the phase structure, microstructure and dielectric and piezoelectric properties of 0.2 wt.% MnO(2) and 0.6 wt.% WO(3)-cloped Pb(Zr(0.52)Ti(0.48))O(3)-Pb(Mn(1/3)Sb(2/3))O(3)-Pb(Zn(1/3)Nb(2/3))O(3) (PZT-PMS-PZN) ceramics was investigated. X-ray diffraction shows that the phase structure of ceramics is transformed from rhombohedral to tetragonal with the increasing of ZnO addition. The bulk density significantly increases when ZnO is added and then it slightly decreases for ZnO addition above 0.2 wt.%. SEM micrographs show the grains of ceramics are uniform and well developed by adding 0.1 wt.% ZnO. The Curie temperature (T(c)) of 270 degrees C is obtained at the 0.1 wt.% ZnO addition. Mechanical quality factor (Q(m)), electromechanical coupling factor (K(p)) and piezoelectric constant (d(33)) increase firstly, and then decrease with the increasing of ZnO addition, while dielectric loss tan 8 drops all the time. The Q(m), K(p), d(33), tan delta and T(c) of the ceramics show the optimum values of 1899,0.55,300 (pC/N). 0.0063 and 270 degrees C, respectively, at the lower sintering temperature of 1120 degrees C and with 0.1 wt.% ZnO addition. (C) 2008 Elsevier Ltd. All rights reserved.