Superconductors Bi-Sr-Cu-O

US4990488A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Hans-Georg von Schnering · Aidlingen, DE
• Winfried Becker · Kelkheim, DE
• Martin Schwarz · Wien, AT
• Leonhard Walz · Rastatt, DE
• Elfi Waldschmidt · Bad Camberg, DE
• Joachim Adam · Rockenberg, DE

Key dates

• Filing date: Nov 23, 1988
• Grant date: Feb 5, 1991
• Expiry date: Nov 23, 2008

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S505/782
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Black crystal compositions having the empirical composition Bi.sub.a Sr.sub.b Cu.sub.c O.sub.d are described where a+b+c=1, A=0.36-0.557, b=0.098-0.496, c=0.1-0.4 and d=approximately 1+a/2. These compositions have a superconducting transition temperature T.sub.c for superconductivity of greater than 20 K and contain a principal phase which crystallizes in the orthorhombic system. They can be prepared from the mixture of the oxides in the atomic ratio stated by heating to 700.degree.-1000.degree. C.