Piezoelectric ceramics and their production methods
US5221872A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 26, 1992 |
| Grant date | Jun 22, 1993 |
| Priority date | — |
| Expiry date | May 26, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N30/8554
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A piezoelectric ceramic comprising at least two kinds of ceramic domains that are different from each other either in composition or in piezoelectric characteristics. It is made possible to produce a piezoelectric ceramic with better piezoelectric characteristics than that composed of a single kind of ceramic domain by having the compositions or the piezoelectric characteristics of each ceramic domain properly selected. For example, it is possible to obtain a piezoelectric ceramic of an extremely small rate of change in resonance frequency in response to a change in temperature by having a ceramic domain with a positive rate of change in resonance frequency in response to a change in temperature and the one with a negative rate of change in resonance frequency in response to a change in temperature combined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.