Piezoelectric ceramic composition
US5762816A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1996 |
| Grant date | Jun 9, 1998 |
| Priority date | — |
| Expiry date | Nov 13, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N30/8548
Abstract
The present invention provides a lead niobate piezoelectric ceramic composition useful for a piezoelectric ceramic element employable at a high temperature, such as a piezoelectric ceramic sensor, which is burned in air and which has a Curie temperature of over 400.degree. C. The piezoelectric ceramic composition contains as a main component a ceramic composition having a tungsten bronze type crystal structure and represented by the formula EQU (Pb.sub.1-(a+b+c) A1.sub.2a A2.sub.b A3.sub.2c/3).sub.x (Nb.sub.1-(d+e+f+g) B1.sub.5d/3 B2.sub.5e/4 B3.sub.f B4.sub.5g/6).sub.y O.sub.3y-.delta. wherein A1 indicates a monovalent metallic element, A2 indicates a divalent metallic element, A3 and B1 each indicate a trivalent metallic element, B2 indicates a tetravalent metallic element, B3 indicates a pentavalent metallic element, B4 indicates a hexavalent metallic element, .delta. indicates a defect amount, and a, b, c, d, e, f, g, x and y satisfy the following relations: PA1 each of a through g.gtoreq.0, PA1 0.015<a+b+c<0.225, PA1 0<d+e+f+g<0.2, PA1 0<x, 0<y, and PA1 x/y<1/2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.