Preparation And Electrical Properties Of PZT Based Piezoelectric Ceramics

With the development of information society,the piezoelectric ceramis has become a kind of important functional materials due to their very excellent ferroelectric,piezoelectric,pyroeleetrie,electro-optic properties.Now,the study of piezoelectric ceramics has attracted extensively attention.In this paper,a review was the latest development of PZT,PLZT and PMN-PT,and then a description of the synthesis of PZT,PLZT and PMN-PT powders and fine-grained ceramics.The fermelectric and piezoelectric have been investigated.This thesis of main content was described as follows:(1)Study iron doped on modification of PZT piezoelectric ceramicsThe preparing of PZT powder and ceramics were proposed.The effect of the composition,sintering condition of powder,pressure,sintering temperature and iron doping of ceramic on dielectric and piezoelectric were investigated.The study found that structure of PZT iron doping has not badly changed.Dense ceramics can be sintered at about 1150℃ with dielectric and piezoelectric properties comparable to that of PZT no iron doping.In arrangement of iron,with the increase of iron content,the more excellent performance of PZT.(Ⅱ)Study on modification of PLZT piezoelectric ceramicsThe content of La on the phase structure of PLZT ceramics,the influence of the structure and electrical properties of crystals were mainly studied in this part.A group of PLZT ceramics was preparation by changing of the content of the lanthanum.The PLZT property of piezoelectric ceramics was studied on the morphotropic phase boundary(MBP)and sintering temperature.The research obtains the following conclusion:the doped La piezoelectric ceramics,piezoelectric properties and dielectric properties were better than that of undoped PZT ceramics.The PLZT of lanthanum 4%has the largest piezoelectric coefficient and density at 1250℃ sintering temperature,2h.The PLZT of lanthanum 4%was the maximum dielectric constant.(Ⅲ)Study on PMN-PT piezoelectric ceramicsThe content of this part mainly through the use of two synthetic method of low temperature synthesis of PMN-PT perovskite phase was studied by optimizing the component design and process conditions.The volatilization of PbO and the pyrochlore phase harmful impurity phase formation.And the excellent of PMN-PT piezoelectric ceramic was obtained by using pre synthesized ceramic powders and PbO protective atmosphere sintering.The research obtains the following conclusion:PMN-PT piezoelectric ceramics was preparation by using synthesis of MgNb2O6 precursor and the lead oxide.Solid state reaction temperature is reduced to 800℃.The PMN-PT perovskite phase has become at 800℃.After the temperature of 1150-1200℃ sintering PMN-PT relaxor ferroelectric ceramics,with two synthesis were prepared by the method of PZT piezoelectric ceramics have good dielectric properties.