JPH03201319A - Manufacture of bismuth oxide superconductor - Google Patents
Manufacture of bismuth oxide superconductorInfo
- Publication number
- JPH03201319A JPH03201319A JP1343487A JP34348789A JPH03201319A JP H03201319 A JPH03201319 A JP H03201319A JP 1343487 A JP1343487 A JP 1343487A JP 34348789 A JP34348789 A JP 34348789A JP H03201319 A JPH03201319 A JP H03201319A
- Authority
- JP
- Japan
- Prior art keywords
- bismuth
- processing
- tape shape
- based oxide
- oxide superconductor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000002887 superconductor Substances 0.000 title claims abstract description 19
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 229910000416 bismuth oxide Inorganic materials 0.000 title abstract 3
- TYIXMATWDRGMPF-UHFFFAOYSA-N dibismuth;oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Bi+3].[Bi+3] TYIXMATWDRGMPF-UHFFFAOYSA-N 0.000 title abstract 3
- 239000000463 material Substances 0.000 claims abstract description 18
- 239000000843 powder Substances 0.000 claims abstract description 11
- 229910052797 bismuth Inorganic materials 0.000 claims description 21
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical group [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims description 20
- 238000010438 heat treatment Methods 0.000 claims description 11
- 238000000034 method Methods 0.000 claims description 11
- 229910052751 metal Inorganic materials 0.000 claims description 9
- 239000002184 metal Substances 0.000 claims description 9
- 238000003754 machining Methods 0.000 abstract 4
- 230000008602 contraction Effects 0.000 abstract 1
- 239000012071 phase Substances 0.000 description 12
- 238000011049 filling Methods 0.000 description 4
- 238000005491 wire drawing Methods 0.000 description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- 230000001747 exhibiting effect Effects 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 238000005096 rolling process Methods 0.000 description 3
- 229910052709 silver Inorganic materials 0.000 description 3
- 239000004332 silver Substances 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- 101100194003 Neurospora crassa (strain ATCC 24698 / 74-OR23-1A / CBS 708.71 / DSM 1257 / FGSC 987) rco-3 gene Proteins 0.000 description 2
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 238000001354 calcination Methods 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 239000000470 constituent Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 238000005245 sintering Methods 0.000 description 2
- 229910001316 Ag alloy Inorganic materials 0.000 description 1
- 229910001020 Au alloy Inorganic materials 0.000 description 1
- 241001148502 Colysis Species 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- MQSRKJKAOOSCFF-UHFFFAOYSA-N [N].[N].[O] Chemical compound [N].[N].[O] MQSRKJKAOOSCFF-UHFFFAOYSA-N 0.000 description 1
- 229910052787 antimony Inorganic materials 0.000 description 1
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 235000010216 calcium carbonate Nutrition 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 239000003353 gold alloy Substances 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000010532 solid phase synthesis reaction Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/60—Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment
Landscapes
- Wire Processing (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は、ビスマス系酸化物超電導体の製造方法に関
するので、特に、より大きな臨界電流密度を得ることが
できるようにするための改良に関するものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a bismuth-based oxide superconductor, and particularly relates to an improvement that enables a larger critical current density to be obtained. It is.
［従来の技術］
近年、より高い臨界温度を示す超電導材料として、セラ
ミック系のものが注目されている。中でも、ビスマス系
酸化物超電導材料は、ｌｌ０Ｋ程度の高い臨界温度を示
すことが知られている。[Prior Art] In recent years, ceramic-based materials have attracted attention as superconducting materials exhibiting higher critical temperatures. Among them, bismuth-based oxide superconducting materials are known to exhibit a high critical temperature of about 110K.
ビスマス系酸化物超電導材料にあっては、１１０に程度
の臨界温度を示す高温超電導相、および８０に程度の臨
界温度を示す低温超電導相などが存在していることが知
られている。このようなビスマス系酸化物超電導材料に
おいては、高い臨界温度でかつ高い臨界電流密度を得る
ことを目的に種々の試みがなされている。It is known that bismuth-based oxide superconducting materials include a high temperature superconducting phase exhibiting a critical temperature of about 110 °C and a low temperature superconducting phase exhibiting a critical temperature of about 80 °C. Various attempts have been made to obtain a high critical temperature and a high critical current density in such bismuth-based oxide superconducting materials.
［発明が解決しようとする課題］
超電導体をケーブルやマグネットに応用するには、高い
臨界温度および高い臨界電流密度が必要である。そのた
め、たとえばビスマス系超電導体を得るためには、上述
した高温超電導相ができるだけ多く生成されるようにし
なければならない。[Problems to be Solved by the Invention] In order to apply superconductors to cables and magnets, high critical temperatures and high critical current densities are required. Therefore, in order to obtain a bismuth-based superconductor, for example, it is necessary to generate as much of the above-mentioned high-temperature superconducting phase as possible.
しかしながら、ビスマス系超電導体を得るためには、従
来、構成物質としては、高温超電導相である２２２３組
成を中心とする組成としながら、金属シースに充填する
際には、低温超電導相である２２１２相と他の相との集
合物とし、加工後あるいは加工途中において、高温超電
導相に相変態させる手法を用いていた。この方法におい
ては、すべてのセラミック部分を高温超電導相に変態さ
せることは難しく、非超電導相が大きな形状で残ってし
まい、成る程度の臨界電流密度以上の性能を得ることが
できなかった。また、高温超電導相を金属シースに充填
した場合、配向性や粒界の結合が十分でなく、高い臨界
電流密度を得ることができなかった。However, in order to obtain a bismuth-based superconductor, conventionally, the constituent materials are mainly composed of 2223 composition, which is a high temperature superconducting phase, but when filling a metal sheath, 2212 phase, which is a low temperature superconducting phase, is used. A method was used to transform the superconducting phase into a high-temperature superconducting phase after or during processing. In this method, it is difficult to transform all the ceramic parts into a high-temperature superconducting phase, and the non-superconducting phase remains in a large shape, making it impossible to obtain performance above the critical current density. Furthermore, when a metal sheath is filled with a high-temperature superconducting phase, the orientation and grain boundary bonding are insufficient, making it impossible to obtain a high critical current density.
それゆえに、この発明の目的は、より大きな臨界電流密
度を得ることができる、ビスマス系酸化物超電導体の製
造方法を提供しようとすることである。Therefore, an object of the present invention is to provide a method for manufacturing a bismuth-based oxide superconductor that can obtain a larger critical current density.
［課題を解決するための手段］
この発明によるビスマス系酸化物超電導体の製造方法は
、１００に以上の臨界温度を持つビスマス系酸化物超電
導材料を主成分とする粉末を、金属シースにて被覆し、
８０％以上の加工度で伸線加工し、さらに８０％以上の
加工度で平角またはテープ状に加工することを特徴とす
るものである。[Means for Solving the Problems] A method for manufacturing a bismuth-based oxide superconductor according to the present invention includes coating a powder mainly composed of a bismuth-based oxide superconducting material having a critical temperature of 100 or higher with a metal sheath. death,
It is characterized by being wire-drawn with a working degree of 80% or more, and further processed into a rectangular or tape shape with a working degree of 80% or more.
この発明において、１００Ｋ以上の臨界温度を持つビス
マス系酸化物超電導材料としては、２２２３組成を基本
組成とするものであるが、ビスマスの一部を、鉛、アン
チモン等で置換したり、リチウムを添加することは、通
常とられる手段である。また、必要により、構成元素は
、それぞれの量が調整される。In this invention, the bismuth-based oxide superconducting material with a critical temperature of 100K or more has a basic composition of 2223, but a part of bismuth is replaced with lead, antimony, etc., or lithium is added. This is the usual procedure. Furthermore, the amounts of each of the constituent elements are adjusted as necessary.
粉末の作製方法としては、固相法、共沈法、硝酸塩共分
解法などを採用することが可能で、また、長時間の焼結
や酸素分圧を制御した雰囲気での焼結が採用される。Powder production methods include the solid phase method, coprecipitation method, and nitrate colysis method, and long-term sintering and sintering in an atmosphere with controlled oxygen partial pressure are also available. Ru.
加工された超電導材料は、熱処理される。熱処理条件と
しては、通常、７８０℃から８６０℃までの温度範囲で
、５時間から３００時間程度の条件が採用される。この
場合の雰囲気は、大気中あるいは酸素分圧を制御した雰
囲気とされる。The processed superconducting material is heat treated. The heat treatment conditions are usually in a temperature range of 780° C. to 860° C. and for about 5 hours to 300 hours. The atmosphere in this case is the atmosphere or an atmosphere in which the partial pressure of oxygen is controlled.
金属シースは、超電導材料と反応せず、かつ加工性が良
好であることを満足する材料から構成される。銀、銀合
金、金、金合金からなるシースや、これらの材料からな
る中間層を配したものが採用される。また、金属シース
は、使用条件で、安定化材として機能することが望まし
い。The metal sheath is made of a material that does not react with superconducting materials and has good workability. A sheath made of silver, a silver alloy, gold, or a gold alloy, or an intermediate layer made of these materials is used. It is also desirable for the metal sheath to function as a stabilizing material under conditions of use.
また、平角またはテープ状への加工が複数回実施される
場合、１パスの加工度は、４０％以上に選ばれることが
好ましい。また、このような加工を行う際、８０％以上
の加工度をもって１パスで達成することが、さらに好ま
しい。Further, when processing into a rectangular or tape shape is carried out multiple times, it is preferable that the degree of processing in one pass is selected to be 40% or more. Further, when performing such processing, it is more preferable to achieve a processing degree of 80% or more in one pass.
熱処理された後、平角またはテープ状への加工と熱処理
とが繰り返されることは、何ら差支えなく、必要により
これらの条件が設定される。After the heat treatment, there is no problem in repeating the processing into a rectangular or tape shape and the heat treatment, and these conditions are set as necessary.
伸線加工に際しては、通常のダイス引きが採用されるが
、ロールダイス、ダークスロールなどの方法を採用して
もよい。平角またはテープ状への加工に際しては、ロー
ル圧延が一般的であるが、プレス圧延、タークスロール
圧延も採用され得る。For the wire drawing process, normal die drawing is used, but methods such as roll die and dark roll may also be used. When processing into a rectangular or tape shape, roll rolling is generally used, but press rolling and Turk roll rolling may also be employed.
［発明の作用および効果］
この発明によれば、１００に以上の臨界温度を持つビス
マス系酸化物超電導材料を主成分とする粉末を、金属シ
ースにて被覆し、８０％以上の加工度で伸線加工し、さ
らに８０％以上の加工度で平角またはテープ状に加工す
ることにより、通常の方法では高温超電導相の粉末を金
属シースに充填することによっては得られないレベルの
高い臨界電流密度を得ることができる。[Operations and Effects of the Invention] According to the present invention, a powder mainly composed of a bismuth-based oxide superconducting material having a critical temperature of 100 or more is coated with a metal sheath, and the powder is stretched with a processing degree of 80% or more. By processing the wire into a rectangular or tape shape with a processing degree of 80% or more, we can achieve a high critical current density that cannot be obtained by filling a metal sheath with high-temperature superconducting phase powder using normal methods. Obtainable.
すなわち、８０％以上の加工度で金属シースを伸線加工
することにより、超電導体は、加工方向に配向化し、さ
らに、８０％以上の加工度で平角またはテープ状に加工
することにより、超電導体はさらに配向化し、緻密化す
ることによって、層の性能の向上が図られる。伸線加工
のみによっては、電流の流れやすいａ−ｂ面が一方向に
揃わないため、平角またはテープ状に加工することによ
って、配向性を改良し、さらに加工度を上述のように８
０％以上に規定することにより、緻密化をより改良する
ことができる。That is, by wire-drawing the metal sheath with a processing degree of 80% or more, the superconductor is oriented in the processing direction, and further, by processing it into a rectangular or tape shape with a processing degree of 80% or more, the superconductor By further orienting and densifying the layer, the performance of the layer can be improved. Because wire drawing alone does not align the a-b planes in which current flows easily, we improve the orientation by processing them into a rectangular or tape shape, and further increase the degree of processing to 8 as described above.
By specifying it to 0% or more, densification can be further improved.
したがって、この発明によって得られたビスマス系酸化
物超電導体は、高い臨界電流密度を示し、ケーブル、マ
グネットなどに有効に利用できるものである。Therefore, the bismuth-based oxide superconductor obtained according to the present invention exhibits a high critical current density and can be effectively used for cables, magnets, etc.
［実施例１
実施例１
Ｂ ｉ２０３ 、ＰｂＯＸ５ ｒｃＯ３、ＣおよびＣｕ
Ｏを用いて、Ｂｉ：Ｐｂ：５Ｃｕ−１，８８：０．３１
：１．９７：３．０３の組成になるように配合し、７１
０時間の仮焼、および、８１０℃で１ａｃＯ３、
ｒ：ｃａ：
２．０３：
４５°Ｃで
２時間の
熱処理を大気中にて行なった後、酸素二窒素＝ｌ：１３
の雰囲気にて、８３７℃で１６０時間の熱処理を行なっ
て、臨界温度が１０７にの粉末を得た。[Example 1 Example 1 B i203 , PbOX5 rcO3, C and Cu
Using O, Bi:Pb:5Cu-1,88:0.31
:1.97:3.03 composition, 71
After calcination for 0 hours and heat treatment at 810°C for 1acO3, r:ca: 2.03: 2 hours at 45°C in the air, oxygen dinitrogen = l:13
Heat treatment was performed at 837° C. for 160 hours in an atmosphere of
このような粉末を、銀パイプに充填し、８４％の加工度
で伸線加工した後、（ａ）８５％の加工度および（ｂ）
６９％の加工度で、それぞれ、圧延加工をし、次いで、
８４０℃で５０時間の熱処理を施し、しかる後、↓９％
の加工を施し、再度、８４０℃で５０時間の熱処理を施
した。After filling such a powder into a silver pipe and wire-drawing it with a working degree of 84%, (a) a working degree of 85% and (b)
Each was rolled at a working degree of 69%, and then
After heat treatment at 840℃ for 50 hours, ↓9%
After that, heat treatment was performed again at 840° C. for 50 hours.
このようにして得られた試料の７７．３にでの臨界電流
密度は、（ａ） ２８５０ ＯＡ／ｃｍ２（ｂ）７１０
０Ａ／ｃｍ２であった。The critical current density at 77.3 of the sample thus obtained is (a) 2850 OA/cm2 (b) 710
It was 0A/cm2.
実施例２
Ｂ ｉ２０３ 、Ｐｂｏ、Ｓ ｒＣＯ３、ＣａＣＯ３、
およびＣｕＯを用いて、Ｂｉ：Ｐｂ：Ｓｒ：Ｃａ：Ｃｕ
＝１．８６：０．３３：１．９６：２．０１：３．０８
の組成になるように配合し、７５０℃で１２時間の仮焼
、および、８００℃で１０時間の熱処理を大気中にて行
なった後、酸素：窒素＝１：１３の雰囲気にて、８３５
℃で１４０時間の熱処理を行なって、臨界温度が１０８
にの粉末を得た。Example 2 B i203 , Pbo, S rCO3, CaCO3,
and CuO, Bi:Pb:Sr:Ca:Cu
=1.86:0.33:1.96:2.01:3.08
After calcination at 750°C for 12 hours and heat treatment at 800°C for 10 hours in the air, 835
After 140 hours of heat treatment at ℃, the critical temperature was 108
powder was obtained.
このような粉末を、銀パイプに充填し、以下の表に示す
条件にて加工した後、８４０℃で５０時間の熱処理を施
し、しかる後、３９％の加工を施し、再度、８４０℃で
５０時間の熱処理を施した。After filling such a powder into a silver pipe and processing it under the conditions shown in the table below, it was heat treated at 840°C for 50 hours, after which it was processed by 39%, and then heated again at 840°C for 50 hours. Heat treated for hours.
このようにして得られた試料の７７．３にでの臨界電流
密度は、表に示すとおりてあった。The critical current density at 77.3 of the sample thus obtained was as shown in the table.
（以下余白）
上記表に示されるように、この発明に従った実施例Ｎｏ
、１〜６の超電導体は、高い臨界電流密度を示している
。(Hereinafter, blank space) As shown in the table above, Example No. according to the present invention
, 1 to 6 show high critical current densities.
Claims (5)
超電導材料を主成分とする粉末を、金属シースにて被覆
し、８０％以上の加工度で伸線加工し、さらに８０％以
上の加工度で平角またはテープ状に加工することを特徴
とする、ビスマス系酸化物超電導体の製造方法。(1) Powder whose main component is a bismuth-based oxide superconducting material with a critical temperature of 100 K or more is coated with a metal sheath, wire-drawn at a processing rate of 80% or more, and further processed at a processing rate of 80% or more. A method for producing a bismuth-based oxide superconductor, characterized by processing it into a rectangular or tape shape.
４０％以上で複数回行われることを特徴とする、請求項
１に記載のビスマス系酸化物超電導体の製造方法。(2) The method for producing a bismuth-based oxide superconductor according to claim 1, wherein the processing into a rectangular or tape shape is performed multiple times at a processing rate of 40% or more in one pass.
れることを特徴とする、請求項１に記載のビスマス系酸
化物超電導体の製造方法。(3) The method for manufacturing a bismuth-based oxide superconductor according to claim 1, wherein processing into a rectangular or tape shape is achieved in one pass.
されることを特徴とする、請求項１ないし３のいずれか
に記載のビスマス系酸化物超電導体の製造方法。(4) The method for producing a bismuth-based oxide superconductor according to any one of claims 1 to 3, wherein the bismuth-based oxide superconductor is heat-treated after being processed into a rectangular or tape shape.
熱処理とが繰返されることを特徴とする、請求項４に記
載のビスマス系酸化物超電導体の製造方法。(5) The method for producing a bismuth-based oxide superconductor according to claim 4, wherein after the heat treatment, processing into a rectangular or tape shape and heat treatment are repeated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34348789A JP3149170B2 (en) | 1989-12-27 | 1989-12-27 | Method for producing bismuth-based oxide superconductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34348789A JP3149170B2 (en) | 1989-12-27 | 1989-12-27 | Method for producing bismuth-based oxide superconductor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03201319A true JPH03201319A (en) | 1991-09-03 |
| JP3149170B2 JP3149170B2 (en) | 2001-03-26 |
Family
ID=18361905
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP34348789A Expired - Lifetime JP3149170B2 (en) | 1989-12-27 | 1989-12-27 | Method for producing bismuth-based oxide superconductor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3149170B2 (en) |
-
1989
- 1989-12-27 JP JP34348789A patent/JP3149170B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP3149170B2 (en) | 2001-03-26 |
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