Title:
PIEZOELECTRIC CERAMICS
Document Type and Number:
Japanese Patent JPH03256382
Kind Code:
A
Abstract:
PURPOSE:To lower Qm and to realize an acoustic transducer whose frequency characteristic is good by a method wherein, at a ternary material composed of specific substances, Ta2O5 and Li2CO3 in a specific ratio is added and this mixture is baked. CONSTITUTION:At a [PbaSrbBac].[(Zn1/3Nb2/3)zTixZry]O3-system, 0.5wt.% or lower of Ta2O5 and 0.5wt.% or lower of Li2CO3 are added and this mixture is baked. For example, prescribed quantities of Pb3O4, ZrO2, ZnO, Nb2O5, BaCO3, SrCO2 and Ta2O5 are weighed and mixed; this mixture is baked temporarily for two hours. After 0.5wt.% or lower of Li2CO3 has been added to a powder obtained by crushing the mixture, this mixture is molded to be a disk; the disk is baked for two hours. Ta2O3 is contained in a ceramic sheet, e.g. [Pb0.8825 Sr0.08Ba0.0375][(Zn1/3Nb2/3)0.125Ti0.40Zr0.475]O3; microscopic empty holes which have been formed by LiCO3 dissociated at a baking operation are provided.
Inventors:
MIKI YASUHIRO
Application Number:
JP5610490A
Publication Date:
November 15, 1991
Filing Date:
March 06, 1990
Export Citation:
Assignee:
ONKYO KK
International Classes:
H01L41/187; (IPC1-7): H01L41/187