Preparation method of low-loss ferrite bismuth-barium titanate-based piezoelectric ceramic

Abstract

The invention discloses a low-loss BiFeO3-BaTiO3-based leadless piezoelectric ceramic and a preparation method thereof. The composition general formula of the low-loss BiFeO3-BaTiO3-based leadless piezoelectric ceramic is (1-x)(Bi1-tLat)FeO3-xBa(Ti1-uSnu)O3+0.5%BiMnO3+yBa(Cu1 / 3Nb2 / 3)O3+zLiBiO3+mBa(W1 / 2Cu1 / 2)O3, wherein t, x, u, y, z and m express mole fractions; t is larger than 0 and less than or equal to 0.02; x is larger than or equal to 0.15 and less than or equal to 0.30; u is larger than 0 and less than 0.05; y is larger than 0 and less than 0.05; z is larger than 0 and less than 0.05; m is larger than 0 and less than 0.05. The preparation method comprises the processes of preparing materials according to the composition general formula, ball milling, molding pills, discharging glue, sintering and the like. By adopting the technologies of reduction of sintering temperature, rapid heating and cooling and high pressure oxygen, volatilization of Bi element is reduced, oxygen vacancy is restrained, valence change of Fe<3+> is prevented in the cooling process, and therefore, the purpose of reducing dielectric loss is achieved, the high temperature leadless piezoelectric ceramic with the dielectric loss lower than 0.5% is prepared, and the leadless piezoelectric ceramic can be practically applied to the high temperature piezoelectric field.

Description

technical field [0001] The invention relates to a preparation method of lead-free piezoelectric ceramics, in particular to a preparation method of low-loss high-performance bismuth ferrite-barium titanate-based high-temperature lead-free piezoelectric ceramics prepared by low-temperature liquid phase rapid sintering under high-pressure oxygen conditions . Background technique [0002] Piezoelectric ceramics are widely used in high-tech fields such as information, laser, navigation, electronic technology, communication, measurement and detection, precision processing and sensing technology. Bismuth ferrite-barium titanate piezoelectric ceramics have received great attention because of their lead-free, low sintering temperature, high Curie temperature, high depolarization temperature and good piezoelectric properties. In 2009, Serhiy O. Leontsev and Richard E. Eitel et al. reported that the piezoelectric constant of the system can be obtained under the condition of sintering ...

AI Technical Summary

Problems solved by technology

In order to maintain the valence balance, these two factors will lead to the generation of a large number of oxygen vacancies, which will eventually make the sample have high dielectric loss and difficult polarization.