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US5411938A Expired / Lapsed US ⏱️ 0.0 years remaining

Sealed glass coating of high temperature ceramic superconductors

Assignee: University of Chicago
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Filing: 1993-07-30
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Granted: 1995-05-02
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Expires: 2013-07-30
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Abstract

Abstract A method and article of manufacture of a lead oxide based glass coating on a high temperature superconductor. The method includes preparing a dispersion of glass powders in a solution, applying the dispersion to the superconductor, drying the dispersion before applying another coating and heating the glass powder dispersion at temperatures below oxygen diffusion onset and above the glass melting point to form a continuous glass coating on the superconductor to establish compressive stresses which enhance the fracture strength of the superconductor.

Inventors

  • 👤 Weite Wu
  • 👤 Cha Y. Chu
  • 👤 Kenneth C. Goretta
  • 👤 Jules L. Routbort

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 20:46
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B41/45; C04B41/50; C04B41/5022; C04B41/80; C04B41/81; C04B41/85; C04B41/86; C23; C23D; C23D5/00; C23D5/02; H; H10; H10N; H10N60/00; H10N60/01; H10N60/0268; H10N60/0661; H10N60/0716; Y; Y10; Y10S; Y10S505/00; Y10S505/70; Y10S505/704; Y10S505/725

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 101 words
A method of manufacturing a coated, high temperature 123 YBaCuO superconductor, comprising the steps of: providing a 123 YBaCuO superconductor article; applying the suspension of said glass powders to form a dispersion of said glass powders on said high temperature 123 YBaCuO superconductor article; heating said dispersion of said glass powders causing melting and formation of a lead oxide based continuous glass coating on said high temperature 123 YBaCuO superconductor article; and cooling said melted lead oxide based continuous glass coating forming a solid glass coating on said superconductor article and formation of compressive stresses on said 123 YBaCuO superconductor article.
Claim 2
Independent Claim 101 words
A method of manufacturing a coated, high temperature 123 YBaCuO superconductor, comprising the steps of: providing a 123 YBaCuO superconductor article; applying the suspension of said glass powders to form a dispersion of said glass powders on said high temperature 123 YBaCuO superconductor article; heating said dispersion of said glass powders causing melting and formation of a lead oxide based continuous glass coating on said high temperature 123 YBaCuO superconductor article; and cooling said melted lead oxide based continuous glass coating forming a solid glass coating on said superconductor article and formation of compressive stresses on said 123 YBaCuO superconductor article.
Claim 3
Dependent Claim 38 words
The method as defined in claim 1 wherein said lead oxide based glass coating comprises 80-95 wt. % lead oxide and further includes about 12-20 wt. % boron oxide and less than 2 wt. % SiO 2 .
Claim 4
Dependent Claim 28 words
The method as defined in claim 1 wherein said lead oxide based glass coating has a coefficient of thermal expansion less than said high temperature 123 YBaCuO superconductor.
Claim 5
Dependent Claim 33 words
The method as defined in claim 3 wherein the coefficient of thermal expansion of said lead oxide based glass coating is about fifty to eighty percent of said high temperature 123 YBaCuO superconductor.
Claim 6
Dependent Claim 31 words
The method as defined in claim 4 wherein said lead oxide based glass coating is selected from the group consisting of a lead-zinc-boron-silica glass, a lead-boron-silica glass and a lead-zinc-fin-boron-silica glass.
Claim 7
Dependent Claim 17 words
The method as defined in claim 1 wherein said solution of said suspension comprises an organic solution.
Claim 8
Dependent Claim 18 words
The method as defined in claim 1 wherein said heating step is performed in an oxygen containing atmosphere.
Claim 9
Dependent Claim 28 words
The method as defined in claim 1 wherein said step of applying the suspension comprises applying a plurality of coatings and drying said coatings before applying another coating.
Claim 10
Dependent Claim 13 words
The method as defined in claim 1 wherein said article comprises a wire.
Claim 11
Independent Claim 128 words
A method of manufacturing a coated high temperature 123 YBaCuO superconductor, comprising the steps of: providing a high temperature 123 YBaCuO superconductor wire; preparing a suspension of glass powders in an organic solution, said glass powders consisting essentiallyof glasses having a lead oxide base of at least 80 wt. %; covering said wire with a coating of said dispersion of glass powders; drying said coating before applying another coating to said wire; and heating said wire and said coating above the melting point of said coating of said glass powders to form a solid, continuous coating of glass on said wire with said glass coating having a coefficient of thermal expansion less than said high temperature superconductor, said continuous solid coating causing compressive residual stresses on said wire.
Claim 12
Independent Claim 128 words
A method of manufacturing a coated high temperature 123 YBaCuO superconductor, comprising the steps of: providing a high temperature 123 YBaCuO superconductor wire; preparing a suspension of glass powders in an organic solution, said glass powders consisting essentiallyof glasses having a lead oxide base of at least 80 wt. %; covering said wire with a coating of said dispersion of glass powders; drying said coating before applying another coating to said wire; and heating said wire and said coating above the melting point of said coating of said glass powders to form a solid, continuous coating of glass on said wire with said glass coating having a coefficient of thermal expansion less than said high temperature superconductor, said continuous solid coating causing compressive residual stresses on said wire.
Claim 13
Dependent Claim 36 words
The method as defined in claim 10 wherein said step of heating said wire is performed at a temperature such that oxygen diffusion in said wire does not cause change of the superconductor wire critical temperature.
Claim 14
Dependent Claim 18 words
The method as defined in claim 11 wherein said temperature of heating is less than about 410° C.
Claim 15
Dependent Claim 18 words
The method as defined in claim 10 wherein said heating step is performed in an oxygen containing atmosphere.
Claim 16
Dependent Claim 29 words
The method as defined in claim 10 wherein the coefficient of thermal expansion of said glass coating is less than eighty percent of that of said high temperature superconductor.

References Cited (Backward Citations)

US3308525A Cited
US4044173A Cited
US4378409A Cited
US3982048A Cited
US5093311A Cited
US5006671A Cited
JPH0574232A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-05-01 1998-10-31 1999-05-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-05-01 2002-10-31 2003-05-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-05-01 2006-10-31 2007-05-02 $7700.00 Window Closed / Lapsed

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