Study On Piezoelectric Materials And Ceramic Target For Magnetoelectric Composite Films

Magnetoelectric(ME) composite films are a kind of energy conversion material which are the research focus of functional materials. The piezoelectric thin films are important parts of M composite films. The piezoelectric thin films made by magnetron sputtering method are closely tied to the quality of the sputtering target. Consequently, it is important to study the piezoelectric ceramic target with controllable piezoelectric properties for the preparation of piezoelectric films and ME composite films.This paper studied a series of piezoelectric ceramic formulas with different piezoelectric properties whose piezoelectric coefficients are from 150 to 600 p C/N on the basis of x Bi(Mg1/2Ti1/2)O3-(1-x)Pb Ti O3(BMT-PT) system and Pb(Zr0.54Ti0.46)O3(PZT) system. Firstly, we studied the effects of Sr, La doping on the properties of BMT-PT piezoelectric ceramics. And we found that the piezoelectric ceramic in the morphotropic phase boundary location when BMT is 0.68. Sr, La ion substitution of a small amount of Pb has little effect on the piezoelectric properties of the ceramics, but excessive Sr can reduce the piezoelectric properties of the ceramics. La doping can significantly improve the piezoelectric performance of BMT-PT ceramics. When the weight ratio of La2O3 was 0.02%wt, the piezoelectric ceramics achieved the best performance. Secondly, we research the influence of Sr doping on the properties of PZT piezoelectric ceramics. With the increasing of Sr content, the piezoelectric properties of PZT ceramics increased first and then decreased. When the doping molar ratio of La ion was 7%mol, the PZT piezoelectric ceramics achieved the best performance. The performance of the piezoelectric ceramics increased with the increasing of Pb content.This paper discussed the preparation of PZT piezoelectric ceramic target with solid-state sintering method. We found that the lateral shrinkage of PZT piezoelectric ceramic sample is 14%, on which base, the target mold being designed. In order to improve the density and uniformity of the target body, the body was molded by cold isostatic pressing method. The sintering temperature and molding press parameters were determined by thermal gravimetric analysis and sintering testing. Eventually we obtained the piezoelectric ceramic target with relative density 94.6%, finding that the target formed single and pure perovskite phase, uniform grain size, clear boundary. The target met the basic needs.