US4906609A
Expired / Lapsed
US
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Fabrication of superconducting oxide wires by powder-in-tube method
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1988-03-31
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Granted: 1990-03-06
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Expires: 2008-03-31
Abstract
Abstract A powder-in-tube method of producing an oxide superconduction wire is disclosed in which a preformed copper oxide superconducting powder is continuously filled into a tube precursor having a U shape cross-section formed from a long strip of metal material. The tube precursor is formed into a tube by bending and welding. The resulting tube is drawn to a reduced cross-section and further heated to sinter the packed powder to form the finished oxide superconducting wire.
Inventors
- 👤 Kazuhisa Yamauchi
- 👤 Kazuya Ohmatsu
- 👤 Tetsuya Ishida
- 👤 Tomoji Gotoh
- 👤 Syuji Yazu
- 👤 Tetsuji Jodai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:33
CPC Classifications
H; H10; H10N; H10N60/00; H10N60/01; H10N60/0268; H10N60/0801; Y; Y10; Y10S; Y10S505/00; Y10S505/70; Y10S505/704; Y10S505/725; Y10S505/739; Y10S505/74; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49014; Y10T29/51; Y10T29/5185; Y10T29/5187
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
95 words
A method of producing a superconducting wire, comprising the steps of: continuously forming a long strip of material into a tube precursor having a U-shaped section; continuously filling the interior of the resulting tube precursor with powder of a copper oxide superconductive ceramic material; forming the tube precursor of U-shaped section into a tube having an O-shaped section and welding together opposed butted edge portions of said strip material, to form a tube; drawing the resulting tube having the powder enclosed therein to a reduced cross-section; and heating the resulting assembly to sinter said powders.
Claim 2
Independent Claim
95 words
A method of producing a superconducting wire, comprising the steps of: continuously forming a long strip of material into a tube precursor having a U-shaped section; continuously filling the interior of the resulting tube precursor with powder of a copper oxide superconductive ceramic material; forming the tube precursor of U-shaped section into a tube having an O-shaped section and welding together opposed butted edge portions of said strip material, to form a tube; drawing the resulting tube having the powder enclosed therein to a reduced cross-section; and heating the resulting assembly to sinter said powders.
Claim 3
Dependent Claim
88 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that said powder of a copper oxide superconductive ceramic material is formed by sintering a mixture of powders comprising oxides, nitrides, fluorides, carbonates, nitrates, oxalates or sulfates of one kind of element α selected from elements of Mg, Ca, Sr and Ba in, one kind of element β selected from elements of Sc, Y, La, and Lanthanides, copper and powders of composite oxides obtained by baking mixtures of said elements and pulverizing them.
Claim 4
Dependent Claim
39 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that said strip material is formed into a tube precursor of C-shaped section before it is formed into said tube precursor of U-shaped section.
Claim 5
Dependent Claim
37 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that at least an inner surface of said strip material is subjected to a surface treatment prior to said first forming step.
Claim 6
Dependent Claim
34 words
A method of producing a superconducting wire as set forth in claim 4, characterized by that said surface treatment is a treatment for forming an oxidized film on a surface of said strip material.
Claim 7
Dependent Claim
34 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that said strip material is formed into a tube precursor of U-shaped section by means of a forming roll.
Claim 8
Dependent Claim
39 words
A method of producing a superconducting wire as set forth in claim 1, characterized in that said edge portions of the strip material are subjected to a grinding operation to expose an activated surface prior to said welding step.
Claim 9
Dependent Claim
25 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that said welding step is carried out by TIG welding.
Claim 10
Dependent Claim
29 words
A method of producing a superconducting wire as set forth in claim 8, characterized by that said TIG welding is carried out in an atmosphere of N 2 gas
Claim 11
Dependent Claim
28 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that said drawing step is carried out by means of a reducing die.
Claim 12
Dependent Claim
34 words
A method of producing a superconducting wire as set forth in claim 10, characterized by that the drawing process is carried out plural times repeatedly at a reduction in area of 30% or less.
Claim 13
Dependent Claim
53 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that said strip material is formed of a metal selected from the group consisting of stainless steel, Cu, Ag, Au, Pt, Pd, Rh, Fe, Pb, Sn, Cd, Ti, W, Mo, Zr, Hf, Ta, and Nb or alloys thereof.
Claim 14
Dependent Claim
60 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that powders of oxides, carbonates, sulfates or nitrates of at least one metal selected from the group consisting of V, Nb, Ta, Mo, W, Ti, Cr, Mn, Ga, In, Cd, Sn, Tl, Pb and Zn are additionally added to said raw material powders as additives.
Claim 15
Dependent Claim
35 words
A method of producing a superconducting wire as set forth in claim 13, characterized by that said additives are added at an atomic ratio of 0.01 to 0.15 based on one mol of said element.
Claim 16
Dependent Claim
26 words
A method of producing a superconducting wire as set forth in claim 1, characterized in that said powders have particle diameters of 30 microns or less.
Claim 17
Dependent Claim
47 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that the sintering is carried out at a temperature between 0° and 100° C. less than the melting point of the material having the lowest melting point of said raw material powders.
Claim 18
Dependent Claim
34 words
A method of producing a superconducting wire as set forth in claim 1, characterized by that the sintered powders are gradually cooled at a rate of 15° C./min or less after said sintering step.
Claim 19
Dependent Claim
27 words
A method of producing a superconducting wire as set forth in claim 2, characterized in that said element α is Ba and said element β is Y.
Claim 20
Dependent Claim
27 words
A method of producing a superconducting wire as set forth in claim 2, characterized by that said element α is Ba and said element β is Ho.
Claim 21
Dependent Claim
27 words
A method of producing a superconducting wire as set forth in claim 2, characterized by that said element α is Ba and said element β is Dy.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-03-05 | 1993-09-04 | 1994-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-05 | 1997-09-04 | 1998-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-05 | 2001-09-04 | 2002-03-06 | $7700.00 | Window Closed / Lapsed |