Process for producing a high-temperature superconductor containing bismuth, strontium, calcium and copper
US5238914A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 1992 |
| Grant date | Aug 24, 1993 |
| Priority date | — |
| Expiry date | Jul 9, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S505/782
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The invention relates to a process for producing a bismuth-, copper-, strontium- and calcium-containing high-temperature superconductor, in which an aqueous solution is produced which has a pH of 0.5-4 and which contains the metals in an atomic ratio corresponding to a high-temperature superconductor, the solution is combined with an oxalic acid solution to precipitate the metals quantitatively as oxalates, the oxalates formed are separated off and decomposed thermally to form the oxides and the latter are reacted in the presence of oxygen at temperatures above 700.degree. C. to form the desired high-temperature superconductor. The process comprises concentrating the aqueous solution of the metal until a precipitate begins to appear and using the oxalic acid as a solution in an organic solvent which is miscible with water The oxalates are decomposed at 550-700.degree. C. in the presence of oxygen.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.