JPS63276819A - Manufacture of ceramic superconductive filament - Google Patents
Manufacture of ceramic superconductive filamentInfo
- Publication number
- JPS63276819A JPS63276819A JP62109823A JP10982387A JPS63276819A JP S63276819 A JPS63276819 A JP S63276819A JP 62109823 A JP62109823 A JP 62109823A JP 10982387 A JP10982387 A JP 10982387A JP S63276819 A JPS63276819 A JP S63276819A
- Authority
- JP
- Japan
- Prior art keywords
- oxygen
- powder
- prepared
- sintered
- sintering
- 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.)
- Pending
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 12
- 239000000919 ceramic Substances 0.000 title claims description 11
- 239000000843 powder Substances 0.000 claims abstract description 34
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 21
- 239000001301 oxygen Substances 0.000 claims abstract description 21
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 20
- 238000005245 sintering Methods 0.000 claims abstract description 14
- 229910052784 alkaline earth metal Inorganic materials 0.000 claims abstract description 7
- -1 alkaline earth metal carbonate Chemical class 0.000 claims abstract description 7
- 229910052761 rare earth metal Inorganic materials 0.000 claims abstract description 6
- 238000011049 filling Methods 0.000 claims abstract description 3
- 229910052751 metal Inorganic materials 0.000 claims description 14
- 239000002184 metal Substances 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 10
- 210000001577 neostriatum Anatomy 0.000 claims 1
- 229910044991 metal oxide Inorganic materials 0.000 abstract description 3
- 150000004706 metal oxides Chemical class 0.000 abstract description 3
- 239000008188 pellet Substances 0.000 abstract description 3
- 229910052802 copper Inorganic materials 0.000 abstract description 2
- 238000005096 rolling process Methods 0.000 abstract description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 abstract 1
- 239000010949 copper Substances 0.000 abstract 1
- 239000011812 mixed powder Substances 0.000 abstract 1
- 239000000203 mixture Substances 0.000 abstract 1
- 238000001354 calcination Methods 0.000 description 7
- 239000013078 crystal Substances 0.000 description 6
- 239000002994 raw material Substances 0.000 description 6
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Substances [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 5
- 238000000465 moulding Methods 0.000 description 4
- 238000010298 pulverizing process Methods 0.000 description 4
- NDVLTYZPCACLMA-UHFFFAOYSA-N silver oxide Chemical compound [O-2].[Ag+].[Ag+] NDVLTYZPCACLMA-UHFFFAOYSA-N 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 150000001342 alkaline earth metals Chemical class 0.000 description 3
- 230000001747 exhibiting effect Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 2
- 238000002156 mixing Methods 0.000 description 2
- 238000009740 moulding (composite fabrication) Methods 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 229910001923 silver oxide Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 229910052712 strontium Inorganic materials 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 229910052692 Dysprosium Inorganic materials 0.000 description 1
- 229910052691 Erbium Inorganic materials 0.000 description 1
- 229910052775 Thulium Inorganic materials 0.000 description 1
- 229910052769 Ytterbium Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- AYJRCSIUFZENHW-DEQYMQKBSA-L barium(2+);oxomethanediolate Chemical compound [Ba+2].[O-][14C]([O-])=O AYJRCSIUFZENHW-DEQYMQKBSA-L 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 229910000765 intermetallic Inorganic materials 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000011368 organic material Substances 0.000 description 1
- 239000011224 oxide ceramic Substances 0.000 description 1
- 229910052574 oxide ceramic Inorganic materials 0.000 description 1
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 description 1
- 229910052705 radium Inorganic materials 0.000 description 1
- 238000005491 wire drawing Methods 0.000 description 1
- 229910052727 yttrium Inorganic materials 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
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
この発明は酸化物セラミックスよりなり、線状あるいは
帯状をした超伝導線条体の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a linear or band-shaped superconducting filament made of oxide ceramics.
セラミックス系超伝導線条体は発電機、変圧器その他の
電気機器やジョセフソン素子などの電子デバイスなどに
用いられる。Ceramic superconducting filaments are used in generators, transformers, and other electrical equipment, as well as in electronic devices such as Josephson elements.
（従来の技術〉
超伝導材料として、金属元素、これら金属の合金や金属
間化合物、有機材料、セラミックスなどが知られている
！近では、特にＬａ、Ｓｒ、Ｃｕ酸化物やＹ、Ｈａ、Ｃ
ｕ酸化物などのセラミックス系超伝導材料の開発が盛ん
に行われている。(Prior art) Metal elements, alloys and intermetallic compounds of these metals, organic materials, ceramics, etc. are known as superconducting materials! Recently, La, Sr, Cu oxides, Y, Ha, C
Ceramic superconducting materials such as u-oxide are being actively developed.
これらセラミックス系超伝導線条体の製造では、一般に
Ｌａ、０． 、Ｙ、０．などの希土類元素の酸化物、５
ｒＣＯ，、、ＢａＣＯ５などのアルカリ土類金属の炭酸
塩およびＣｕＯなどの原料粉末を加圧成形したのち、焼
結する。成形体は、焼結により微小な結晶粒が集った多
結晶体となる。また、焼結中に上記炭酸塩からＣ０２が
放出され、また酸化物および雰囲気中の酸素が結晶中に
取り込まれ、超伝導性を示す結晶構造を形成する。酸化
物の結晶構造は酸素イオンの充填状態により決るので、
焼結中における酸素と上記酸化物や炭酸塩との反応は超
伝導性に大きく影響する。In the production of these ceramic superconducting strands, generally La is 0. , Y, 0. Rare earth element oxides such as 5
Carbonates of alkaline earth metals such as rCO, . . . BaCO5 and raw material powders such as CuO are press-molded and then sintered. The molded body becomes a polycrystalline body made up of fine crystal grains by sintering. Further, during sintering, C02 is released from the carbonate, and oxides and oxygen in the atmosphere are incorporated into the crystal, forming a crystal structure exhibiting superconductivity. The crystal structure of an oxide is determined by the filling state of oxygen ions, so
The reaction between oxygen and the above oxides and carbonates during sintering greatly affects superconductivity.
（発明が解決しようとする問題点）
しかし、上記従来の製造方法では、原料粉末を大気ある
いは酸素雰囲気中で焼結せずに、たとえば金属管内に封
入した状態で焼結すると、酸素との未反応部分、すなわ
ち酸素濃度が不十分な部分が焼結を終えた成品中にかな
り残っていた。未反応部分は超伝導性を示す結晶構造を
形成しないので、このことが臨界温度Ｔｃ、臨界電流密
度Ｊｃあるいは臨界磁場Ｈｃの向上の一つの障害となっ
ていた。(Problems to be Solved by the Invention) However, in the above-mentioned conventional manufacturing method, if the raw material powder is sintered in a metal tube, for example, instead of being sintered in the air or an oxygen atmosphere, it is difficult to sinter the raw material powder with oxygen. A considerable amount of reactive parts, ie, parts with insufficient oxygen concentration, remained in the finished product after sintering. Since the unreacted portion does not form a crystal structure exhibiting superconductivity, this has been an obstacle to improving the critical temperature Tc, critical current density Jc, or critical magnetic field Hc.
そこで、この発明は焼結体の殆どが超伝導性を示す結晶
構造からなり、高い超伝導性を示すセラミックス系超伝
導線条体を製造することができる方法を提供しようとす
るものである。Therefore, the present invention aims to provide a method for manufacturing a ceramic superconducting wire body in which most of the sintered body has a crystal structure exhibiting superconductivity and exhibits high superconductivity.
（問題点を解決するための手段）
この発明のセラミックス系超伝導線条体の製造方法は、
希土類元素の酸化物、アルカリ土類金属の炭酸塩および
ＣｕＯの粉末を調製し、調製粉末を金属管に充填し、調
製粉末入り金属管を伸線したのちに焼結して超伝導線条
体を製造する方法において、前記調製粉末を酸素供給粉
末材とともに金属管内に充填し、焼結を行う。(Means for solving the problem) The method for manufacturing a ceramic superconducting wire of the present invention includes:
Powders of rare earth element oxides, alkaline earth metal carbonates, and CuO are prepared, the prepared powders are filled into a metal tube, the metal tube containing the prepared powders is drawn, and then sintered to form a superconducting wire. In the method for manufacturing, the prepared powder is filled into a metal tube together with an oxygen-supplying powder material and sintered.
製造するセラミックス系超伝導線条体の種類に応じて、
希土類元素およびアルカリ土類金属から所要の金属が選
ばれる。希土類から選ばれるものは、たとえばＬａ、Ｅ
ｕ、Ｄｙ、ｌｌｏ、Ｅｒ、Ｔｍ、ＹｂまたはＹであり、
アルカリ土類金属から選ばれるものはＣａ。Depending on the type of ceramic superconducting wire to be manufactured,
The required metal is selected from rare earth elements and alkaline earth metals. Those selected from rare earths include, for example, La, E
u, Dy, lo, Er, Tm, Yb or Y,
Ca is selected from the alkaline earth metals.
Ｓｒ、ＲａまたはＢａである。Sr, Ra or Ba.
粉末の調製は原料粉末の混合あるいは混合後、熱処理だ
けでもよいが、これにベレット状成形、仮焼および粉砕
の工程を加えてもよい。この場合の成形は、簡単な加圧
成形が用いられる。仮焼は常圧で、空気あるいは酸素雰
囲気中で行い、仮焼温度は７００〜１０００℃程度、ま
た仮焼時間は数時間程度である。仮焼により原料粉末中
の水分、揮発分その他の不純物を分離する。さらには、
上記仮焼、粉砕に続いてベレット状成形、焼結および粉
砕の工程を加えてもよい。粉末を成形するには、通常の
成形方法たとえばＣＩＰ、 ＨＩＰ％ホットプレスなど
が用いられる。焼結は常圧あるいは加圧のもとで、空気
あるいは酸素雰囲気中で行う。焼結温度は９００〜１１
００℃程度であり、焼結時間は２〜６４ｈｒ程度である
。The powder may be prepared simply by mixing the raw material powders or by heat treatment after mixing, but the steps of pellet-forming, calcining, and pulverization may also be added. In this case, simple pressure molding is used for the molding. The calcination is performed at normal pressure in an air or oxygen atmosphere, the calcination temperature is about 700 to 1000°C, and the calcination time is about several hours. Moisture, volatile matter, and other impurities in the raw material powder are separated by calcining. Furthermore,
Following the above-mentioned calcination and pulverization, steps of pellet-forming, sintering, and pulverization may be added. To mold the powder, conventional molding methods such as CIP, HIP% hot press, etc. are used. Sintering is performed under normal pressure or increased pressure in an air or oxygen atmosphere. Sintering temperature is 900-11
The temperature is about 00°C, and the sintering time is about 2 to 64 hours.
酸素供給粉末材として、Ａｇｅ、 ＰＬＯあるいは＾ｕ
Ｏなどの金属酸化物粉末が用いられる。成形前の粉末お
よび酸素供給粉末材を充填する金属管は鋼管、ステンレ
ス鋼管、Ｐｔ管などが用いられる。原料粉末とある程度
反応するステンレス鋼等の金属管の内面は不活性金属、
たとえばＡｕあるいはｐｔなどによりコーティングして
おくことが望ましい。As an oxygen supply powder material, Age, PLO or ^u
Metal oxide powder such as O is used. A steel pipe, a stainless steel pipe, a Pt pipe, or the like is used as the metal pipe to be filled with the powder before molding and the oxygen-supplying powder material. The inner surface of the metal tube, such as stainless steel, which reacts to some extent with the raw material powder, is an inert metal,
For example, it is desirable to coat it with Au or PT.
調製粉末および酸素供給粉末材を充填した金属管を伸線
するには、通常の圧延、引抜き加工あるいは両者の組合
せが用いられる。Conventional rolling, drawing, or a combination of both may be used to draw the metal tube filled with the prepared powder and the oxygen-supplying powder material.
伸線後の焼結は、上記焼結と同様に行う。Sintering after wire drawing is performed in the same manner as the above sintering.
（作用）
この発明の方法では、焼結中に加熱により酸素供給粉末
材から酸素が放出されるので、調製粉末は酸素濃度の高
い雰囲気中におかれることになる。このため、酸素は焼
結体内部から供給されることになり、酸素との反応が促
進される。これより、焼結体は酸素濃度が高くなり、超
伝導特性にすぐれた焼結体となる。(Function) In the method of the present invention, oxygen is released from the oxygen-supplying powder material by heating during sintering, so the prepared powder is placed in an atmosphere with a high oxygen concentration. Therefore, oxygen is supplied from inside the sintered body, and the reaction with oxygen is promoted. This increases the oxygen concentration in the sintered body, resulting in a sintered body with excellent superconducting properties.
（実施例）
第１図はこの発明によるセラミックス系超伝導線条体製
造法の作業工程の一例を示すフローチャートである。(Example) FIG. 1 is a flowchart showing an example of the working steps of the method for manufacturing a ceramic superconducting wire body according to the present invention.
図面に示すように、まず酸化イツトリウム、炭酸バリウ
ムおよび酸化鋼の微細粉末を混合し、ベレットに加圧成
形した。ベレットを９００℃で、２時間仮焼したのち、
これを粉砕した。As shown in the drawing, first, fine powders of yttrium oxide, barium carbonate, and oxidized steel were mixed and pressure-formed into a pellet. After calcining the pellet at 900℃ for 2 hours,
This was crushed.
上記粉砕により得られた粉末を酸化銀粉末とともに、外
径２０ｍｍの白金に充填した。The powder obtained by the above pulverization was filled together with silver oxide powder into a platinum chamber having an outer diameter of 20 mm.
粉末を充填した白金管を圧延および引抜きにより外径２
ａｒｍの線材に延伸加工した。そして、得られた線材
を圧力２０００ｋｇｆ／ｃ＋ｍ２のもとで９５０℃に加
熱して８時間保持し、炉冷した。A platinum tube filled with powder is rolled and drawn to an outer diameter of 2.
The wire rod of the arm was stretched. Then, the obtained wire rod was heated to 950°C under a pressure of 2000 kgf/c+m2, held for 8 hours, and then cooled in a furnace.
このようにして得られた線材の電流密度Ｊｃは４５０
Ａ／ｃｍ２であった。これに対し、従来法 （鋼管に酸
化銀は充填しない）により作られた線材の臨界電流密度
Ｊｃは３０ Ａ／ｃｍ”であった。The current density Jc of the wire obtained in this way is 450
It was A/cm2. On the other hand, the critical current density Jc of the wire made by the conventional method (in which the steel tube was not filled with silver oxide) was 30 A/cm''.
以上、ＹＢａ２（：ｕ、０．−、の製造について説明し
たが、他の材料たとえばＬａ５ｒＣｕＯについても同様
に製造することができる。Although the production of YBa2(:u, 0.-) has been described above, other materials such as La5rCuO can be similarly produced.
（発明の効果）
この発明によれば、焼結中に加熱により酸素供給粉末材
から酸素が放出されるので、調製粉末は酸素濃度の高い
雰囲気中で反応する。したがって、焼結体は酸素濃度が
高くかつ均一となり、超伝導特性にすぐれたものが得ら
れる。こわより、臨界温度、臨界電流密度および臨界磁
場は高くなり、電気機器および電子デバイスの性能向上
を図ることが可能である。(Effects of the Invention) According to the present invention, since oxygen is released from the oxygen-supplying powder material by heating during sintering, the prepared powder reacts in an atmosphere with a high oxygen concentration. Therefore, the sintered body has a high and uniform oxygen concentration, and has excellent superconducting properties. Because of stiffness, the critical temperature, critical current density, and critical magnetic field become higher, and it is possible to improve the performance of electrical equipment and electronic devices.
第１図はこの発明によるセラミックス系超伝導線条体製
造法の一例を示す作業工程図である。FIG. 1 is a work process diagram showing an example of the method for manufacturing a ceramic superconducting wire body according to the present invention.
Claims (1)
ＣｕＯの粉末を調製し、調製粉末を金属管に充填し、調
製粉末入り金属管を伸線したのちに空気または酸素雰囲
気中で焼結して超伝導線条体を製造する方法において、
前記調製粉末を酸素供給粉末材とともに金属管内に充填
し、焼結を行うことを特徴とするセラミックス系超伝導
線条体の製造方法。Powders of rare earth element oxides, alkaline earth metal carbonates, and CuO are prepared, the prepared powders are filled into a metal tube, the metal tubes containing the prepared powders are drawn, and then sintered in an air or oxygen atmosphere. In a method for manufacturing a superconducting striatum,
A method for manufacturing a ceramic superconducting filament, comprising filling the prepared powder together with an oxygen-supplying powder material into a metal tube and sintering it.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62109823A JPS63276819A (en) | 1987-05-07 | 1987-05-07 | Manufacture of ceramic superconductive filament |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62109823A JPS63276819A (en) | 1987-05-07 | 1987-05-07 | Manufacture of ceramic superconductive filament |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63276819A true JPS63276819A (en) | 1988-11-15 |
Family
ID=14520113
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62109823A Pending JPS63276819A (en) | 1987-05-07 | 1987-05-07 | Manufacture of ceramic superconductive filament |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63276819A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6448327A (en) * | 1987-07-24 | 1989-02-22 | Asea Brown Boveri | Manufacture of ceramic high temperature superconductor sheathed wire |
| JPH01304618A (en) * | 1988-05-31 | 1989-12-08 | Furukawa Electric Co Ltd:The | Manufacture of oxide superconductive filament |
| JPH02160317A (en) * | 1988-12-12 | 1990-06-20 | Mitsubishi Cable Ind Ltd | Manufacture of superconducting wire |
| EP0426164A2 (en) * | 1989-11-02 | 1991-05-08 | International Superconductivity Technology Center | Process for preparing oxide superconductor |
| EP0427209A2 (en) * | 1989-11-08 | 1991-05-15 | International Superconductivity Technology Center | Process for producing oxide superconductor |
-
1987
- 1987-05-07 JP JP62109823A patent/JPS63276819A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6448327A (en) * | 1987-07-24 | 1989-02-22 | Asea Brown Boveri | Manufacture of ceramic high temperature superconductor sheathed wire |
| JPH01304618A (en) * | 1988-05-31 | 1989-12-08 | Furukawa Electric Co Ltd:The | Manufacture of oxide superconductive filament |
| JPH02160317A (en) * | 1988-12-12 | 1990-06-20 | Mitsubishi Cable Ind Ltd | Manufacture of superconducting wire |
| EP0426164A2 (en) * | 1989-11-02 | 1991-05-08 | International Superconductivity Technology Center | Process for preparing oxide superconductor |
| EP0427209A2 (en) * | 1989-11-08 | 1991-05-15 | International Superconductivity Technology Center | Process for producing oxide superconductor |
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