Piezoelectric ceramic material
US6461532B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2000 |
| Grant date | Oct 8, 2002 |
| Priority date | — |
| Expiry date | Oct 27, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/475
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A piezoelectric ceramic material comprising a bismuth layer compound containing MII, Bi, Ti and O wherein MII is selected from Sr, Ba and Ca, and containing MIIBi4Ti4O15 type crystals, wherein MII, is represented by SrxBayCaz wherein x+y+z=1, utilizes thickness shear vibration when 0≦x≦ 1, 0≦y≦0.9, and 0≦z≦1, and thickness extensional vibration when 0≦x<0.9, 0≦y≦0.9, and 0≦z<1. Also provided is a piezoelectric ceramic material comprising a bismuth layer compound containing Ca, Bi, Ti, Ln and 0 wherein Ln is a lanthanoid, and containing CaBi4Ti4O15 type crystals, wherein the atomic ratio Ln/(Ln+Ca) is in the range: 0<Ln/(Ln+Ca)<0.5. These piezoelectric ceramic materials are free of lead, and have a high Curie point and improved piezoelectric characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.