| The application of preparing technology of nanopowder and doping modification process provided a new approach for the improvement of properties of piezoelectric ceramics. The fabrication of nanocrystalline PZT powders and the effects of many kinds of additives, such as La3+, CNTs and γ'-Fe4N on the physical, dielectric and piezoelectric properties for PZT piezoelectric ceramics were investigated in this report.A number of chemical synthesis techniques have been reported to yield pure homogeneous PZT powders in recent years. Among all these methods, sol-gel and hydrothermal techniques are important. In this paper, we report the synthesis of pure, homogeneous nanocrystalline PZT powders at a relatively low temperature, from comparatively inexpensive raw materials by a hybrid method of sol. and hydrothermal. This method produced very reactive PZT powder, from which PZT ceramics with good compositional and structural homogeneity can be derived.PZT with a composition of Pb(Zr0.52Ti0.48)O3, which is near the morphotropic phase boundary (MPB) was selected in the present study. powders are characterized by DSC/TGA, FT-IR, XRD, and SEM analysis. The starting materials used were reagent grade lead nitrate [Pb(NO3)2] , zirconium nitrate hydrate [Zr(NO3)4 · 5H2O], tetra-butyl titanate [Ti(OC4H9)4], using NaOH as the mineralizer. PZT phase started to form at a soaking temperature as low as 220℃, while phase-pure PZT powders were obtained at 270℃2h. The PZT powders can be used to prepare PZT ceramics at a fairly low temperature but with electrical properties that are comparable to the PZT ceramics synthesized by conventional methods. The 1150℃2h-sintered PZT ceramics fabricated from nanocrystalline powders, with an average grain size of 1.5 μm and relative density of 97.5%, have a high piezoelectric constant d33 of 220 pC/N, a dielectric constant ε33T/ε0 of 1006 measured at 1kHz, an electromechanical coupling coefficient kp of 0.5 and a...
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