The effect of tantalum substitution on the microstructure and dielectric and piezoelectric properties of Pb_(0.99)(Zr_(0.95)Ti_(0.05))_(0.98)Nb_(0.02)O_3 ceramics

摘要

Lead zirconate titanate (PZT95/5) based piezoelectric ceramics with the compositions Pb-0.99(Zr0.95Ti0.05)(0.98)Ta0.02O3 (PZTT) and Pb0.99-0.5x(Zr0.95Ti0.05)(0.98-x)Nb0.02TaxO3 (PZTN), where x = 0.0, 0.005, 0.010, 0.015 and 0.020 were synthesized using conventional solid state sintering at 1250 A degrees C for 2 h in air. The effect of tantalum substitution on the microstructure, dielectric and piezoelectric properties of the samples were studied. The results showed that the Ta-doped samples had finer microstructures. The PZTT samples had microstructures with finer grains (average grain size of 3.80 A mu m) in comparison with the PZTN samples (average grain size of 5.33 A mu m). The relative densities of the PZTN and PZTT samples were approximately 94.1 and 94.4%, respectively. Moreover, the relative dielectric constant (epsilon(r)), piezoelectric coefficient (d(31)) and elastic compliance (S-11 (E)) of the samples reached the maximum values of 349, - 15.2 PC/N and 8.42 Pm-2/N, respectively at 1.5 mol% tantalum substitution. Furthermore, the relative dielectric constant (epsilon(r)), piezoelectric coefficient (d(33)) and voltage coefficient (g(33)) of the PZTN samples reached the optimal values of 306, 69 PC/N and 25.44 mV m/N, respectively, in comparison with the PZTT samples (329, 67 PC/N and 21.43 mV m/N, respectively). The results indicate that the tantalum doped PZT95/5 ceramics can be used for pulsed power devices.