Magnesium -boride superconducting wires fabricated using thin high temperature fibers

• US 20050074220A1
• Filed: 04/29/2003
• Published: 04/07/2005
• Est. Priority Date: 05/10/2002
• Status: Active Grant

• Current Assignee: Christopher Mark Rey
• Original Assignee: Christopher Mark Rey
• Inventors: Rey, Christopher Mark
• Granted Patent: US 6,946,428 B2
• Time in Patent Office: Days
• US Class Current: 385/141
• CPC Class Codes: H10N 60/0856 of devices comprising metal borides, e.g. MgB2

Abstract

This invention uses a novel approach for the fabrication of low temperature superconducting (LTS) magnesium di-boride (MgB₂) wire or cable. This approach employs the use of a “high temperature fiber or tape” as a high performance substrate material. High temperature fiber substrates are low-cost, round, light-weight, non-magnetic, and capable of withstanding, without degradation, the high reaction temperatures necessary to form the superconducting phase of Mg—B.

Claims

1. A method for producing a superconducting wire, tape or cable consisting of:

a thin non-superconducting high temperature fiber or tape;

a non-superconducting buffer layer or layers;

a precursor superconducting material;

a means for combining said thin high temperature fiber or tape template, said non-superconducting buffer layer or layers, and said precursor superconducting material using one or more of the known thick and/or thin film deposition techniques in combination with one or more of the known texturing techniques to fabricate a multi-layer film

and a means for combining/stacking/bundling/twisting/transposing said multi-layer fiber film into a multi-filament conductor.

2. The method of claim 1, wherein said precursor low temperature superconducting material is a stoichiometric mixture of chemical elements of a magnesium boride superconductor.

3. The method of claim 1, wherein said precursor low temperature superconducting material is a non-stoichiometric mixture of chemical elements of a magnesium boride superconductor.

4. The method of claim 1, wherein said precursor low temperature superconducting material is a mixture of chemical elements of a magnesium boride superconductor doped with other elements such as titanium, niobium, zirconium, tantalum, vanadium, silicon carbide, tungsten carbide, boron nitride etc. to enhance the critical superconducting properties.

5. The method of claim 1, wherein said multi-layer film includes a noble metallic and dielectric coatings to enhance electric and thermal stability and provide electrical insulation and environmental protection.

6. The method of claim 1, wherein said multi-layer film includes physical defects and/or chemical dopants/impurirteis in the magnesium boride superconducting material to enhance the pinning force which increases the critical current of the superconducting multi-layer film.

7. A method for producing a superconducting wire, tape or cable consisting of:

a thin non-superconducting high temperature fiber or tape template;

a precursor superconducting material;

a means for combining said thin high temperature fiber or tape template and said precursor superconducting material using one or more of the known thick and/or thin film deposition techniques to fabricate a multi-layer film

and a means for combining/stacking/bundling/twisting/transposing said multi-layer fiber film into a multi-filament conductor.

8. The method of claim 7, wherein said precursor low temperature superconducting material is a stoichiometric mixture of chemical elements of a magnesium-boride superconductor.

9. The method of claim 7, wherein said precursor low temperature superconducting material is a non-stoichiometric mixture of chemical elements of a magnesium-boride superconductor.

10. The method of claim 7, wherein said precursor low temperature superconducting material is a mixture of chemical elements of a magnesium-boride superconductor doped with other elements such as titanium, niobium, zirconium, tantalum, vanadium, silicon carbide, tungsten carbide, boron nitride, etc. to enhance the critical superconducting properties.

11. The method of claim 7, wherein said multi-layer film includes a noble metallic and dielectric coating to enhance electric and thermal stability and provide electrical insulation and environmental protection.

12. The method of claim 7, wherein said multi-layer film includes physical defects and/or chemical dopants/impurities in the magnesium boride superconducting material to enhance the pinning force which increases the critical current of the superconducting multi-layer film.

13. A method for producing a superconducting wire, tape or cable consisting of:

a thin non-superconducting high temperature fiber or tape;

a non-superconducting buffer layer or layers;

a precursor superconducting material;

a means for combining said thin high temperature fiber or tape template, said non-superconducting buffer layer or layers, and said precursor superconducting material using one or more of the known thick and/or thin film deposition techniques to fabricate a multi-layer film

and a means for combing/stacking/bundling/twisting/transposing said multi-layer fiber film into a multi-filament conductor.

14. The method of claim 13, wherein said precursor low temperature superconducting material is a stoichiometric mixture of chemical elements of a magnesium boride superconductor.

15. The method of claim 13, wherein said precursor low temperature superconducting material is a non-stoichiometric mixture of chemical elements of a magnesium boride superconductor.

16. The method of claim 13, wherein said precursor low temperature superconducting material is a mixture of chemical elements of a magnesium boride superconductor doped with other elements such as titanium, niobium, zirconium, tantalum, vanadium, silicon carbide, tungsten carbide, boron nitride, etc. to enhance the critical superconducting properties.

17. The method of claim 13, wherein said multi-layer film includes a noble metallic and dielectric coatings to enhance electric and thermal stability and to provide electrical insulation and environmental protection.

18. The method of claim 13, wherein said multi-layer film includes physical defects and/or chemical dopants/impurities in the magnesium boride superconducting material to enhance the pinning force which increases the critical current of the superconducting multi-layer film.