(Bi, Pb).sub.2, Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.x superconductor and method of making same utilizing sinter-forging
US5821201A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 13, 1996 |
| Grant date | Oct 13, 1998 |
| Priority date | — |
| Expiry date | Nov 13, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S505/739
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A (BiPb).sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.x (Bi223) superconductor with high J.sub.c, phase purity, density and mechanical strength is formed from Bi2223 powder which is synthesized from a mixture of Bi.sub.2 O.sub.3, PbO, SrCO.sub.3, CaCo.sub.3 and CuO. The mixture is milled, then dried and calcined to synthesize the Bi2223 powder with the desired phase purity. The calcination is performed by heating the dried mixture for 50 hours at 840.degree. C. The partially synthesized powder is then milled for 1-4 hours before calcining further for another 50 hours at 855.degree. C. to complete the synthesis. After calcination, the Bi2223 powder is cold pressed to a predetermined density and sinter forged under controlled temperature and time to form a Bi2223 superconductor with the desired superconducting properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.