Process for making superconductors using barium hydroxide
US5061683A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 31, 1988 |
| Grant date | Oct 29, 1991 |
| Priority date | — |
| Expiry date | May 31, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S505/738
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
There is disclosed an improved process for preparing a superconducting composition having the formula M.sub.w A.sub.z Cu.sub.v O.sub.x wherein M is selected from the group consisting if Bi, Tl, Y, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm Yb and Lu; A is at least one alkaline earth metal selected from the group consisting of Ba, Ca and Sr; x is at least 6; w is at least 1; z is at least 2 and v is at least 1; said composition having a superconducting transition temperature of above 77 K, preferably above about 90 K; said process consisting essentially of (a) forming a suspension having an M:A:Cu atomic ratio of w:z:v by mixing A(OH).sub.2, AO or AO.sub.2 and M.sub.2 O.sub.3 with an aqueous solution of cupric carboxylate or cupric nitrate at a temperature from about 50.degree. C. to about 100.degree. C., or mixing A(OH).sub.2 with an aqueous solution of Cu carboxylate, nitrate or a mixture thereof and M carboxylate, nitrate or a mixture thereof at a temperature from about 50.degree. C. to about 100.degree. C.; (b) drying the suspension formed in step (a) to obtain a precursor powder; and (c) heating and cooling the powder under specified conditions to form the desired superconducting compositi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.