Optimization of processing parameters of PZT ceramic prepared by sol-gel derived nanocrystalline PZT powders

In this study, nanocrystalline PZT powders have been synthesized by a sol-gel route. The crystallized PZT powders were pressed and then sintered at various temperatures from 900° to 1200°C, with a holding time up to 4 hr to obtain optimum condition of sintering. PZT ceramic sintered at 1100°C has maximum theoretical density of 95% and the material had a dielectric constant of 1119 and tan ¿ = 0.005 at 1 KHz and d₃₃ of 100 at room temperature. Also for purpose of densification behavior comparison, PZT ceramics with 7 wt. % excess PbO were traditionally prepared. It was found that owing to the formation of liquid phase in ceramics containing excess PbO, these ceramics can achieve maximum theoretical density 94% at lower temperatures and shorter soaking times, but they have lowers dielectric constant (~600) in comparison with sol-gel derived and conventionally prepared PZT ceramics.