Nb-doped PLZT piezoelectric ceramics
US5595677A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 1995 |
| Grant date | Jan 21, 1997 |
| Priority date | — |
| Expiry date | May 30, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N30/853
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
PLZT piezoelectric ceramics having the general formula (Pb.sub.1-x La.sub.x)(Zr.sub.y Ti.sub.1-y).sub.1-(x/4) O.sub.3 are fabricated in a hot forging process using PbO, TiO.sub.2, ZrO.sub.2, and La.sub.2 O.sub.3 powders as starting materials with Nb.sub.2 O.sub.5 added to provide niobium (Nb) as a dopant. The ZrO.sub.2 and TiO.sub.2 powders are mixed at a molar ratio of y/(1-y), calcined at approximately 1300.degree.-1500.degree. C., ball milled in acetone, and evaporated to a dry powder. The mixture of ZrO.sub.2 and TiO.sub.2 is then combined with the PbO, La.sub.2 O.sub.3, and Nb.sub.2 O.sub.5 powders, and the new mixture is ball milled in acetone, evaporated to a dry powder, calcined at approximately 700.degree.-850.degree. C., and sifted to obtain a particle size of approximately 0.3-2.0 .mu.m. The final PLZT powder is formed into the desired shape by cold pressing followed by sintering at approximately 1000.degree.-1150.degree. C. in oxygen. The PLZT ceramic material is further densifted to about 98.5% of the material's theoretical maximum density by heating to approximately 1175.degree.-1275.degree. C. at 800-1200 psi uniaxial pressure. The resulting high performance Nb-doped…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.