JPH0816022B2 - Method for manufacturing oxide superconductor - Google Patents
Method for manufacturing oxide superconductorInfo
- Publication number
- JPH0816022B2 JPH0816022B2 JP62121916A JP12191687A JPH0816022B2 JP H0816022 B2 JPH0816022 B2 JP H0816022B2 JP 62121916 A JP62121916 A JP 62121916A JP 12191687 A JP12191687 A JP 12191687A JP H0816022 B2 JPH0816022 B2 JP H0816022B2
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- single crystal
- oxide
- perovskite structure
- 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.)
- Expired - Lifetime
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Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/01—Manufacture or treatment
- H10N60/0268—Manufacture or treatment of devices comprising copper oxide
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Press-Shaping Or Shaping Using Conveyers (AREA)
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
Description
【発明の詳細な説明】 産業上の利用分野 本発明は、方向によって特性が異なり、かつ優れた超
電導特性を示す酸化物超電導体多結晶焼結体の製造方法
に関するものである。Description: TECHNICAL FIELD The present invention relates to a method for producing an oxide superconductor polycrystalline sintered body which has different characteristics depending on the direction and exhibits excellent superconducting characteristics.
従来の技術 従来の酸化物超電導体多結晶焼結体の製造方法は、酸
化物原料にバインダーを加え、金型で成型し、高温の空
気中で燃焼するというものである。2. Description of the Related Art A conventional method for producing a polycrystalline oxide superconductor polycrystalline sintered body is to add a binder to an oxide raw material, mold it with a mold, and burn it in high temperature air.
発明が解決しようとする問題点 しかし、従来のこのような製造方法に基づき得られた
焼結体は、微小な単結晶が多数、無秩序な結晶方位をむ
いて寄り集まったものであり、その超電導特性は、単結
晶よりも劣っている。またその電気特性は、焼結体のい
ずれの方位に対しても同じ、すなわち等方的である。DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, the sintered body obtained based on the conventional manufacturing method as described above is composed of a large number of minute single crystals, which are gathered in a disordered crystal orientation, and their superconductivity The characteristics are inferior to the single crystal. Moreover, the electrical characteristics are the same for any orientation of the sintered body, that is, isotropic.
一方、単結晶は、焼結体に比べその超電導特性は良い
が、生産性に劣り、大型のものができないなどの問題が
ある。On the other hand, a single crystal has better superconducting properties than a sintered body, but has a problem in that it is inferior in productivity and a large one cannot be formed.
本発明はかかる点に鑑みなされたもので、多結晶焼結
体でありながら、単結晶に匹敵する超電導特性と結晶異
方性を有し、かつ単結晶よりも生産性に優れ、大型もの
が容易に得られる酸化物超電導体多結晶焼結体の製造方
法を提供することを目的としている。The present invention has been made in view of such a point, even though it is a polycrystalline sintered body, it has superconducting characteristics and crystal anisotropy comparable to a single crystal, and is superior in productivity to a single crystal, and has a large size. It is an object of the present invention to provide a method for producing an easily obtained oxide superconductor polycrystalline sintered body.
問題点を解決するための手段 本発明は上記問題点を解決するため、層状ペロブスカ
イト構造酸化物超電導体用原料に、一軸方向に伸長し
た、層状ペロブスカイト構造酸化物単結晶粒子を、２〜
30重量％、均一に添加し、かつ伸長方向が一定に並ぶよ
うに成型し、焼結によって、前記単結晶粒子が前記原料
を吸収して成長して、特定方向に配向した焼結体とする
ことにより、多結晶焼結体でありながら、単結晶に匹敵
する超電導特性と結晶異方性を有し、かつ単結晶よりも
生産性に優れ、大型ものが容易に得られる酸化物超電導
体多結晶焼結体の製造方法を提供するものである。Means for Solving the Problems In order to solve the above problems, the present invention provides a raw material for a layered perovskite structure oxide superconductor with a uniaxially stretched layered perovskite structure oxide single crystal particle,
30% by weight, uniformly added, and molded so that the elongation direction is aligned, and by sintering, the single crystal particles absorb and grow the raw material to obtain a sintered body oriented in a specific direction. As a result, even though it is a polycrystalline sintered body, it has superconducting properties and crystal anisotropy comparable to that of a single crystal, and is more productive than a single crystal. A method for manufacturing a crystal sintered body is provided.
作用 本発明は、前記した製造方法により、多結晶焼結体で
ありながら、単結晶に匹敵する超電動特性と結晶異方性
を有した、酸化物超電導体焼結体を得ることができる。Effect of the Invention According to the above-described manufacturing method, the present invention can provide an oxide superconductor sintered body which is a polycrystalline sintered body but has superelectric characteristics and crystal anisotropy comparable to a single crystal.
実施例 以下本発明の一実施例について、図面を用いて詳細に
説明する。Embodiment An embodiment of the present invention will be described below in detail with reference to the drawings.
（実施例１） 酸化イットリウム（Y2O3）、酸化バリウム（BaO）と
酸化銅（CuO）をＹ0.3Ba0.7Cu1の比で含むようでそれぞ
れ秤量し、混合の後、900℃の空気中で５時間焼成し
た。これをもう一度粉砕、混合したあと、900℃の空気
中で12時間焼成し、再度粉砕した。(Example 1) Yttrium oxide (Y 2 O 3 ), barium oxide (BaO) and copper oxide (CuO) were weighed so as to contain Y 0.3 Ba 0.7 Cu 1 , and mixed, and then air at 900 ° C. Baking for 5 hours. This was pulverized and mixed again, and then calcinated in air at 900 ° C. for 12 hours and pulverized again.
次に、融液法により作った上記と同一組成の、Ｙ0.3B
a0.7Cu1酸化物単結晶を、ａ軸方向に100〜200μｍ、そ
の垂直方向に10〜30μｍの大きさを有する、微小な単結
晶粒子に加工した。この微小単結晶粒子を、先程の粉末
粒子に、全量の、２〜30重量％の割合になるように、均
一に添加、湿式混合し、押し出し成型法を用いて、添加
した微小単結晶粒子が、その長手方向、すなわち、ａ軸
方向に並んだ成型体を得た。この成型体を、空気中で、
950℃で24時間焼成した。Next, Y 0.3 B of the same composition as the above prepared by the melt method
The a 0.7 Cu 1 oxide single crystal was processed into fine single crystal particles having a size of 100 to 200 μm in the a-axis direction and 10 to 30 μm in the vertical direction. The fine single crystal particles were added uniformly to the powder particles described above so that the proportion of the whole powder was 2 to 30% by weight, wet-mixed, and the added fine single crystal particles were formed by an extrusion molding method. A molded body was obtained which was aligned in its longitudinal direction, that is, in the a-axis direction. In the air, this molded body,
It was baked at 950 ° C for 24 hours.
得られた焼結体の電気抵抗を測定した。その結果、加
えた微小単結晶粒子がａ軸方向に揃った方向の電気抵抗
は、その垂直方向よりも２倍以上小さかった。またこの
焼結体の電気抵抗を液体窒素（77K）温度で測定した結
果、超電導性を示した。すなわちこのような方法で形成
した焼結体は、超電導体であった。得られた焼結体を、
Ｘ線解析で調べたところ、層状ペロブスカイト構造を示
していた。そして加えた微小単結晶粒子がａ軸方向に揃
った方向に、顕著なａ軸配向が見られた。図は、本実施
例の結晶構造である層状ペロブスカイト構造の構成要素
であるペロブスカイト構造を示したもので、図におい
て、１はCu、２はＯ、３はＹまたはBaである。層状ペロ
ブスカイト構造は、この構成要素がある周期をもって、
層状に積み重なったものである。実際超電導体となるの
は、この中から酸素が適当に抜けたものと考えられる。
ａ軸方向は、この図において、横方向であり、縦方向は
Ｃ軸方向である。The electric resistance of the obtained sintered body was measured. As a result, the electric resistance in the direction in which the added fine single crystal particles were aligned in the a-axis direction was twice or more smaller than that in the vertical direction. The electric resistance of this sintered body was measured at liquid nitrogen (77K) temperature, and it showed superconductivity. That is, the sintered body formed by such a method was a superconductor. The obtained sintered body,
When examined by X-ray analysis, it showed a layered perovskite structure. A remarkable a-axis orientation was found in the direction in which the added fine single crystal particles were aligned in the a-axis direction. The figure shows a perovskite structure which is a constituent element of the layered perovskite structure which is the crystal structure of the present embodiment. In the figure, 1 is Cu, 2 is O, 3 is Y or Ba. The layered perovskite structure has this component with a certain period,
It is a stack of layers. It is considered that oxygen actually escapes from the inside to become a superconductor.
In this figure, the a-axis direction is the horizontal direction, and the vertical direction is the C-axis direction.
この材料について、同じプロセスで、微小単結晶粒子
を加えなかったものを作成し、その臨界電流特性を測定
比較した。その結果、本実施例の方法で得たもののａ軸
配向方法の、超電導臨界電流は、微小単結晶粒子を加え
なかったものに比べ、その超電導の臨界電流が約20％向
上した。この理由は、超電導に寄与する電子の動き易い
方向が、層状ペロブスカイト構造において、そのａ軸方
向であり、本実施例の焼結体では、その方向に結晶方位
が良く揃っているため、向上したものと考えられる。This material was prepared by the same process without adding fine single crystal particles, and its critical current characteristics were measured and compared. As a result, the superconducting critical current of the a-axis orientation method obtained by the method of the present example was improved by about 20% as compared with the superconducting critical current in which fine single crystal particles were not added. The reason for this is that the direction in which the electrons that contribute to superconductivity tend to move is the a-axis direction in the layered perovskite structure, and the sintered body of this example has a good crystal orientation in that direction, which is improved. It is considered to be a thing.
（実施例２） ランタン（La）、バリウム（Ba）、銅（Cu）が、La
1.84Ba0.16Cu1の比からなる酸化物超電導体材料につい
て、実施例１と同様のプロセスを経て、配向性焼結体を
得た。得られた焼結体の電気抵抗は、やはり異方性をも
ち、そのａ軸配向方向の電気抵抗は、その垂直方向に対
し、約２倍以上低かった。またこの焼結体の電気抵抗を
液体ヘリウム（4K）温度で測定した結果、超電導性を示
した。すなわちこのような方法で形成した配向性焼結体
も、超電導体であった。さらにＸ線解析で調べたとこ
ろ、層状ペロブスカイト構造を示しており、微小単結晶
粒子を加えた方向にａ軸配向していることが確認され
た。(Example 2) Lanthanum (La), barium (Ba), and copper (Cu) are La.
An oriented sintered body was obtained from the oxide superconductor material having a ratio of 1.84 Ba 0.16 Cu 1 through the same process as in Example 1. The electrical resistance of the obtained sintered body also had anisotropy, and the electrical resistance in the a-axis orientation direction was about twice or more lower than that in the vertical direction. The electric resistance of this sintered body was measured at liquid helium (4K) temperature, and it showed superconductivity. That is, the oriented sintered body formed by such a method was also a superconductor. Further examination by X-ray analysis showed a layered perovskite structure, and confirmed that the a-axis was oriented in the direction in which the fine single crystal particles were added.
（実施例３） 希土類（Lu,Yb,Tm,Er,Ho,Dy,Gd,Eu,Sm,Ndの酸化物）
バリウム、銅を銅１に対し、希土類とバリウムの比が、
0.4と0.6からなる酸化物超電導体材料について、実施例
１と同様のプロセスを経て、配向性焼結体を得た。得ら
れた焼結体の電気抵抗は、やはり異方性をもち、そのａ
軸配向方向の電気抵抗は、その垂直方向に対し、約２倍
以上低かった。またこの焼結体の電気抵抗を液体ヘリウ
ム（4K）温度で測定した結果、超電導性を示した。すな
わちこのような方法で形成した配向性焼結体も、超電導
体であった。さらにＸ線解析で調べたところ、層状ペロ
ブスカイト構造を示しており、微小単結晶粒子を加えた
方向にａ軸配向していることが確認された。(Example 3) Rare earth (Lu, Yb, Tm, Er, Ho, Dy, Gd, Eu, Sm, Nd oxide)
The ratio of rare earth and barium is 1 barium and copper to 1 copper.
An oriented sintered body was obtained from the oxide superconductor material consisting of 0.4 and 0.6 through the same process as in Example 1. The electric resistance of the obtained sintered body also has anisotropy, and a
The electrical resistance in the axial orientation direction was about twice or more lower than that in the vertical direction. The electric resistance of this sintered body was measured at liquid helium (4K) temperature, and it showed superconductivity. That is, the oriented sintered body formed by such a method was also a superconductor. Further examination by X-ray analysis showed a layered perovskite structure, and confirmed that the a-axis was oriented in the direction in which the fine single crystal particles were added.
以上述べた如く、本発明の方法によれば、方向により
異方性を有し、超電導特性に優れた、酸化物超電導体多
結晶体を得ることができる。As described above, according to the method of the present invention, it is possible to obtain an oxide superconductor polycrystalline body having anisotropy depending on the direction and excellent in superconducting properties.
本実施例の製造方法によれば、層状ペロブスカイト構
造を有する酸化物超電導体については、いずれの材料に
ついても適用できるものである。第１図は、実施例１の
結晶構造について、示したものであるが、実施例２〜３
の場合は、この構造において、Ｙ、Baの代わりに、それ
ぞれの実施例で用いられた、Cu、Ｏ以外の元素で置き代
えたものである。According to the manufacturing method of the present embodiment, any material can be applied to the oxide superconductor having the layered perovskite structure. FIG. 1 shows the crystal structure of Example 1, but Examples 2-3
In this case, in this structure, elements other than Cu and O used in the respective examples were replaced in place of Y and Ba.
本発明では、加えた微小単結晶粒子の量は、２〜30重
量％であったが、得られた焼結体では、この微小単結晶
粒子が核となって、まわりに加えた、同一組成の粉末を
吸収し、大きく成長していた。その結果、加えた微小単
結晶粒子の量よりもはるかに多くの量が、その方向に配
向した焼結体が得られた。したがって、単結晶よりもは
るかに大型のものが得られ、生産性に優れた製造方法で
ある。In the present invention, the amount of the fine single crystal particles added was 2 to 30% by weight, but in the obtained sintered body, the fine single crystal particles serve as nuclei and have the same composition added to the surroundings. Had absorbed the powder and had grown greatly. As a result, it was possible to obtain a sintered body in which an amount much larger than the amount of the added fine single crystal particles was oriented in that direction. Therefore, a manufacturing method that is much larger than a single crystal and has excellent productivity is provided.
本発明の配向性は、加える微小単結晶粒子の形状を細
長いものとしておくことにより、この湿式混合材料を、
細かい菅を通して、押し出してやると、最も抵抗の少な
い方向、すなわち、その長手方向に揃っていくという性
質と、焼結により、粒径の大きい粒子は、細かい粒子を
吸収して成長していくという性質を有効に生かすことに
よって、はじめて得られたものである。The orientation of the present invention is obtained by setting the shape of the fine single crystal particles to be added to be elongated so that the wet mixed material is
When extruded through a fine tube, the property of aligning in the direction with the least resistance, that is, the longitudinal direction, and the fact that sintering causes large particles to absorb fine particles and grow. It was obtained for the first time by effectively utilizing the properties.
本実施例では、いずれもａ軸方向に配向した多結晶焼
結体を得たが、加える微小単結晶粒子の長手方向を、ｃ
軸方向にとれば、ｃ軸配向の多結晶焼結体の得られるこ
とは、明らかであり、すなわち本発明の方法によれば、
任意の結晶方位に配向した多結晶焼結体が得られるもの
である。In each of the examples, a polycrystalline sintered body oriented in the a-axis direction was obtained, but the longitudinal direction of the fine single crystal particles to be added was changed to c
It is obvious that a c-axis oriented polycrystalline sintered body can be obtained in the axial direction, that is, according to the method of the present invention,
A polycrystalline sintered body oriented in any crystal orientation can be obtained.
実施例２〜３のものについても、同じプロセスで焼成
時に圧力を加えなかったものを作成し、その臨界電流特
性を測定比較した。その結果いずれの材料についても、
実施例１の場合と同様に、その超電導の臨界電流が約20
％以上向上した。この理由は実施例１の場合と同様と考
えられる。Regarding Examples 2 to 3 as well, the same process was used in which no pressure was applied during firing, and the critical current characteristics were measured and compared. As a result, for both materials,
As in the case of Example 1, the superconducting critical current is about 20.
Improved by more than%. The reason is considered to be the same as in the case of the first embodiment.
発明の効果 以上述べた如く、本発明は、層状ペロブスカイト構造
酸化物超電導体用原料に、一軸方向に発達した、層状ペ
ロブスカイト構造酸化物単結晶粒子を、均一に添加し、
かつ発達方向が一定方向に並ぶように成型し、焼結する
ことにより、多結晶焼結体でありながら、単結晶に匹敵
する超電導特性と結晶異方性を有し、かつ単結晶よりも
生産性に優れ、大型ものが容易に得られる酸化物超電導
体多結晶焼結体の製造方法を提供するものである。Effect of the Invention As described above, the present invention, the layered perovskite structure oxide superconductor raw material, uniaxially developed, layered perovskite structure oxide single crystal particles, uniformly added,
Moreover, by molding and sintering so that the development direction is aligned in a certain direction, it is a polycrystalline sintered body, but it has superconducting characteristics and crystal anisotropy comparable to single crystals, and is more producible than single crystals. It is intended to provide a method for producing an oxide superconductor polycrystalline sintered body which is excellent in properties and can be easily obtained in a large size.
図は本発明に用いた酸化物超電導体の結晶構造である層
状ペロブスカイト構造の、構成要素であるペロブスカイ
ト構造を示した構造図である。 １……Cu、２……Ｏ、３……ＹまたはBa。The figure is a structural diagram showing a perovskite structure which is a constituent element of the layered perovskite structure which is the crystal structure of the oxide superconductor used in the present invention. 1 ... Cu, 2 ... O, 3 ... Y or Ba.
フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 // Ｂ２８Ｂ 3/20 ＺＡＡ Ｈ０１Ｂ 12/00 ＺＡＡ Continuation of front page (51) Int.Cl. 6 Identification number Office reference number FI technical display location // B28B 3/20 ZAA H01B 12/00 ZAA
Claims (3)
原料に、一軸方向に伸長した、層状ペロブスカイト構造
酸化物単結晶粒子を、２〜30重量％、均一に添加し、か
つ伸長方向が一定に並ぶように成型し、焼結によって、
前記単結晶粒子が前記原料を吸収して成長することによ
り、特定方向に配向した焼結体とすることを特徴とする
酸化物超電導体の製造方法。1. A layered perovskite structure oxide superconductor raw material is uniformly added with 2 to 30% by weight of layered perovskite structure oxide single crystal particles which are uniaxially stretched, and the stretching direction is aligned. By molding and sintering,
A method for producing an oxide superconductor, wherein the single crystal particles absorb the raw material and grow to form a sintered body oriented in a specific direction.
して、Ａ−Ba−Cu酸化物（但しＡは、Ｙ、希土類）を用
いたことを特徴とする特許請求の範囲第（１）項記載の
酸化物超電導体の製造方法。2. Oxidation according to claim 1, wherein an A-Ba-Cu oxide (where A is Y and a rare earth) is used as the layered perovskite structure superconductor oxide. Method for manufacturing superconductors.
Dy、Gd、Eu、Sm、Ndを用いたことを特徴とする特許請求
の範囲第（２）項記載の酸化物超電導体の製造方法。3. Rare earths such as La, Lu, Yb, Tm, Er, Ho,
Dy, Gd, Eu, Sm, Nd was used, The manufacturing method of the oxide superconductor of Claim (2) characterized by the above-mentioned.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62121916A JPH0816022B2 (en) | 1987-05-19 | 1987-05-19 | Method for manufacturing oxide superconductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62121916A JPH0816022B2 (en) | 1987-05-19 | 1987-05-19 | Method for manufacturing oxide superconductor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63285159A JPS63285159A (en) | 1988-11-22 |
| JPH0816022B2 true JPH0816022B2 (en) | 1996-02-21 |
Family
ID=14823084
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62121916A Expired - Lifetime JPH0816022B2 (en) | 1987-05-19 | 1987-05-19 | Method for manufacturing oxide superconductor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0816022B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2622123B2 (en) * | 1987-09-21 | 1997-06-18 | 古河電気工業株式会社 | Method for producing flake-like oxide superconductor |
| JPH01246173A (en) * | 1988-03-28 | 1989-10-02 | Kyocera Corp | Oxide superconductor and production thereof |
| JPH07106906B2 (en) * | 1990-04-13 | 1995-11-15 | 新日本製鐵株式会社 | Oxide superconducting material containing rare earth element and method for producing the same |
| JP2905862B2 (en) * | 1993-01-05 | 1999-06-14 | 工業技術院長 | Method for producing superconducting whisker composite |
| JP4595236B2 (en) * | 2000-04-28 | 2010-12-08 | 株式会社豊田中央研究所 | Thermoelectric material manufacturing method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6136162A (en) * | 1984-07-27 | 1986-02-20 | 導電性無機化合物技術研究組合 | Electroconductive ceramic composite body |
| JPH062614B2 (en) * | 1984-10-31 | 1994-01-12 | 三菱マテリアル株式会社 | Ceramic material |
| JPS63277555A (en) * | 1987-05-08 | 1988-11-15 | Kanegafuchi Chem Ind Co Ltd | Oxide superconductive ceramic sintered material and production thereof |
-
1987
- 1987-05-19 JP JP62121916A patent/JPH0816022B2/en not_active Expired - Lifetime
Non-Patent Citations (1)
| Title |
|---|
| ＪａｐａｎｅｓｅＪｏｕｒｎａｌｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓＶｏｌ．２６ｐ．Ｌ３７７〜Ｌ３７９ |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63285159A (en) | 1988-11-22 |
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