Preparation And Properties Of MZr_0.5Ti_0.5O₃（M=La,Nd,Ce,Pb） Piezoelectric Material

The preparation and application of lead-free piezoelectric ceramics is one of the researchissues in material science. Rare earth elements have the rich electrical properties, opticalproperties and magnetic properties, in addition to the unique chemical properties and physicalcharacteristics. The piezoelectric ceramics doped by rare earth oxides can improve the dielectricand piezoelectric significantly. This paper focuses on the piezoelectric material doped with rareearth elements (La,Nd,Ce). The nano-scale lead-free piezoelectric ceramics were prepared andthe catalytic performance and hysteresis loops of obtained products were studied. The maincontents are as follows:1) In the preparation process, the solid-phase method process is relatively simple, low cost,but the agglomeration of the powder is larger. And the stearic acid method can be used toimprove denseness, the material powder size is relatively small, the agglomeration is alsosmaller.2) XRD, TEM and Raman were employed to characterized microstructure of the sample.The performances of physics and chemistry of these powders were measured, and the graindiameters of samples were50-70nm.3) TG-DTG was used to measure the catalytic properties of as-products. The results showedthat the powder materials had some catalytic properties; they can reduce the decompositiontemperature of AP and increase the decomposition rate.4) The powder materials were used to produce piezoelectric ceramics and the ferroelectrictester were used to test the material’s hysteresis loop, leakage current and resilience. The resultsare as following:(1) The Pr and Er of piezoelectric ceramics were increased with the increasing of appliedelectric which shows a better resistance of breakdown characteristics.(2) Compared with PZT and RE zirconium titanate, Pr had be reduced and the Er had beincreased, which may be due to the strong anisotropy of rare earth.(3) When the density of the material structure is not high enough, the leakage current is toobig, so we cannot test the hysteresis loops of the piezoelectric film.(4) When reduced the test frequency, the hysteresis loop will change from the “waist" stateinto the square, and the Pr and Er increased by a big margin. (5) When reduced the test temperature, the hysteresis loop also will change from the “waist"state into the square, and the Pr and Er increased by a big margin.