Sintered piezoelectric ceramic, piezoelectric ceramic device, monolithic piezoelectric ceramic device, and method for producing sintered piezoelectric ceramic
AssigneeMurata Mnufacturing Co., Ltd.
InventorsKoichi Kawano, Kazuya Kamada
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Abstract
Disclosed is a sintered piezoelectric ceramic which is resistant to the high voltage for polarization with no dielectric breakdown and has good moisture resistance. When a plurality of the ceramics are fired, they are prevented from being fused and combined together. The production costs of the ceramic are low. The sintered piezoelectric ceramic comprises particulate or agglomerate zirconia grains dispersed in piezoelectric ceramic grains, in which the mean grain size of the piezoelectric ceramic grains is smaller than that of the zirconia grains.
Claims20
A sintered piezoelectric ceramic comprising a mixture of zirconia grains and piezoelectric ceramic grains, in which the mean grain size of the piezoelectric ceramic grains is smaller than that of the zirconia grains.
A method for producing sintered piezoelectric ceramics comprising the steps of
- providing a calcined piezoelectric ceramic body;
- grinding the calcined body into a powder;
- mixing the powder with a binder to obtain a binder-containing mixture;
- molding the mixture into a molding;
- and
- firing the molding into a sintered molding;
- wherein zirconia grains whose mean grain size is larger than that of the grains of the calcined piezoelectric ceramic are combined with the ceramic after the step of providing the calcined body and before the step of obtaining the molding.
Dependencies are inferred from the claim text.