JPH0517203A - Superconducting ceramics - Google Patents

Superconducting ceramics

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Publication number
JPH0517203A
JPH0517203A JP3094815A JP9481591A JPH0517203A JP H0517203 A JPH0517203 A JP H0517203A JP 3094815 A JP3094815 A JP 3094815A JP 9481591 A JP9481591 A JP 9481591A JP H0517203 A JPH0517203 A JP H0517203A
Authority
JP
Japan
Prior art keywords
superconducting
ceramics
present
superconductivity
oxide
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
Application number
JP3094815A
Other languages
Japanese (ja)
Inventor
Shunpei Yamazaki
舜平 山崎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Semiconductor Energy Laboratory Co Ltd
Original Assignee
Semiconductor Energy Laboratory Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Semiconductor Energy Laboratory Co Ltd filed Critical Semiconductor Energy Laboratory Co Ltd
Priority to JP3094815A priority Critical patent/JPH0517203A/en
Publication of JPH0517203A publication Critical patent/JPH0517203A/en
Pending legal-status Critical Current

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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

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  • Compositions Of Oxide Ceramics (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Superconductor Devices And Manufacturing Methods Thereof (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)

Abstract

PURPOSE:To easily obtain superconducting ceramics at a low cost by layering the structure of copper oxide so that two layers are formed in one molecule, superconducting carriers in the layers and imparting superconductivity at a prescribed temp. or above. CONSTITUTION:High purity fine powders of Y2O3, BaCO3, CaCO3, CuO, etc., are mixed in a desired ratio, tabletted and heated at about 700 deg.C in the air to obtain a temporarily sintered body. This sintered body is pulverized, press- molded and subjected to normal sintering at about 900 deg.C in the air to produce superconducting ceramics having a compsn. represented by the formula (where A is Y, B is Ba, B' is Ca, each of x and x' is 0-1, each of y and y' is 2.0-4.0, each of z and z' is 1.0-4.0 and each of w and w' is 4.0-10.0). These ceramics have superconductivity at the temp. of liq. nitrogen (77K) or above.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は酸化物セラミック系超電
導材料に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxide ceramic superconducting material.

【０００２】[0002]

【従来の技術】従来、超電子材料は、水銀、鉛等の元
素、NbN,Nb3Ge,Nb3Ga 等の合金またはNb3(Al0.8Ge0.2)
等の三元素化合物よりなる金属材料が用いられている。
しかしこれらのTc( 超電導臨界温度) オンセットは25K
までであった。2. Description of the Related Art Conventionally, superelectronic materials have been elements such as mercury and lead, alloys such as NbN, Nb 3 Ge and Nb 3 Ga, or Nb 3 (Al 0.8 Ge 0.2 ).
A metal material made of a three-element compound such as is used.
However, these Tc (superconducting critical temperature) onset is 25K
It was up to.

【０００３】他方、近年、セラミック系の超電導材料が
注目されている。この材料は最初IBM のチュ−リッヒ研
究所よりBa-La-Cu-O( バラクオ) 系酸化物高温超電導体
として報告され、さらにLSCO( 第二銅酸−ランタン−ス
トロンチュ−ム）として知られてきた。しかし、これら
はTcオンセットが30K しか得られなった。On the other hand, in recent years, attention has been paid to ceramic-based superconducting materials. This material was first reported as a Ba-La-Cu-O (oxide) high-temperature oxide superconductor by the Zurich Research Laboratories of IBM and was further known as LSCO (cupric acid-lanthanum-strontium). It was However, they obtained only 30K Tc onset.

【０００４】[0004]

【発明が解決しようとする課題】これら従来の酸化物セ
ラミックスはペロブスカイト型の構造を利用しているも
ので、Tcも30K がその限界であった。このため、このTc
o をさらに高くし、望むべくは液体窒素温度(77K )また
はそれ以上で動作せしめることが強く求められていた。These conventional oxide ceramics utilize a perovskite type structure, and their Tc is limited to 30K. Therefore, this Tc
There was a strong demand for higher o and, if desired, operation at liquid nitrogen temperatures (77K) or higher.

【０００５】[0005]

【課題を解決するための手段】本発明は、かかる高温で
超電導を呈するべく、新しい素材を探し求めた。その結
果、銅の酸化物の層構造を１分子内に２層有する新しい
ペロブスカイト型構造において、液体窒素温度（77K)以
上で超電導性を有する材料を得ることが可能となった。The present invention has sought a new material to exhibit superconductivity at such high temperatures. As a result, it became possible to obtain a material having superconductivity at a liquid nitrogen temperature (77K) or higher in a new perovskite structure having two layers of copper oxide layers in one molecule.

【０００６】本発明の超電導性セラミックスは、銅の酸
化物が構造において層構造を有し、その構造も１分子内
で１層または２層構成を有し、その層内をキャリアが超
電導をしていることを特徴とするが、その組成は、例え
ば(A1-x Bx)yCuzOw ・(A1-X 'B'x')y'Cuz Ow',ｘ,x' ＝
０〜1,ｙ,y' ＝2.0 〜4.0 好ましくは2.5 〜3.5,ｚ,z'
＝1.0 〜4.0 好ましくは1.5 〜3.5,w,w'＝4.0 〜10.0好
ましくは６〜８で一般的に示し得るものである。Ａはイ
ットリュ−ム族より選ばれた元素およびその他のランタ
ノイドより選ばれた元素のうちの１種類を用いている。
イットリュ−ム族とは理化学辞典( 岩波書店 1963年４
月１日発行）によれば、Y(イットリュ−ム),Gd( ガドリ
ニュ−ム),Yb( イッテルビュ−ム),Eu( ユ−ロピウム),
Tb( テルビウム),Dy( ジスプロシウム),Ho( ホルミウ
ム),Er（エルビウム),Tm( ツリウム),Lu( ルテチウム),
Sc( スカンジウム）およびその他のランタノイドを用い
る。In the superconducting ceramics of the present invention, the copper oxide has a layer structure in its structure, and the structure also has a one-layer or two-layer structure in one molecule, in which the carriers conduct superconductivity. The composition is, for example, (A 1-x Bx) yCuzOw ・ (A 1- X'B'x ') y'Cu z Ow', x, x '=
0 to 1, y, y '= 2.0 to 4.0, preferably 2.5 to 3.5, z, z'
= 1.0-4.0, preferably 1.5-3.5, w, w '= 4.0-10.0, preferably 6-8. A uses one of the elements selected from the ytterbm group and other lanthanoids.
What is the It-Rum tribe? A physics and chemistry dictionary (Iwanami Shoten 1963 April
According to (issued on the 1st of the month), Y (it ryum), Gd (gadolinium), Yb (ytterbum), Eu (europium),
Tb (terbium), Dy (dysprosium), Ho (holmium), Er (erbium), Tm (thulium), Lu (lutetium),
Sc (scandium) and other lanthanoids are used.

【０００７】またB,B'はRa( ラジュ−ム),Ba( バリュ−
ム),Sr( ストロンチュ−ム),Ca( カルシュ−ム),Mg
（マグネシュ−ム),Be( ベリリュ−ム）より選ばれた元
素より成る。Further, B and B'are Ra (radium) and Ba (value
), Sr (strontium), Ca (calcium), Mg
Consists of elements selected from (Magnesium) and Be (Berylium).

【０００８】本発明は銅を層構造とせしめ、これを１分
子内で対称構造の２層構造とし、この層の最外核電子の
電子の軌道により超電導を呈せしめ得るモデルを前提と
している。The present invention is based on a model in which copper has a layered structure and has a two-layered structure having a symmetric structure within one molecule, and superconductivity can be exhibited by the orbit of the electron of the outermost nuclear electron in this layer.

【０００９】かかる構造においては、銅の酸化物をより
層構造とせしめ、この層をキャリアが移動しやすくする
ため、例えば(A1-x Bx)yCuzOw ・(A1-X'B'x')y'Cuz'Ow'
におけるＡ，Ｂの選ばれる元素が重要である。特にＡの
元素はイットリュ−ム族の元素またはランタノイドの元
素、一般には元素周期表３ａ（理化学辞典( 岩波書店
1963年４月１日発行）による）の族である。本発明は、
その元素のうちの１種類を用いている。さらに本発明
は、B,B'として元素周期表における２ａ族（理化学辞典
( 岩波書店 1963年４月１日発行）による）であるRa(
ラジュ−ム),Ba（バリュ−ム),Sr( ストロンチュ−ム),
Ca( カルシュ−ム),Mg( マグネシュ−ム),Be( ベリリュ
−ム）より選ばれた元素を用いている。In such a structure, for example, (A 1-x Bx) yCuzOw- (A 1- X'B'x ') is used to make the layer structure of copper oxide and to facilitate the movement of carriers in this layer. ) y'Cuz'Ow '
The element selected from A and B is important. In particular, the element of A is an element of the yttrium group or an element of a lanthanoid, and generally the periodic table of elements 3a (Rikagaku Dictionary (Iwanami Shoten
(Published April 1, 1963))). The present invention is
One of the elements is used. Furthermore, the present invention refers to the group 2a in the Periodic Table of Elements as B, B '
Ra (from Iwanami Shoten, published April 1, 1963)
Radium), Ba (volume), Sr (strontium),
An element selected from Ca (calcium), Mg (magnesium), and Be (beryrum) is used.

【００１０】本発明は出発材料の酸化物または炭酸塩を
混合し、一度加圧して、出発材料の酸化物または炭酸塩
により(A1-x Bx)yCuzOw ・(A1-X 'B'x')y'Cuz'Ow' 型の
分子を作り得る。In the present invention, the oxide or carbonate of the starting material is mixed, pressurized once, and the oxide or carbonate of the starting material is used to obtain (A 1-x Bx) yCuzOw. (A 1- X'B'x ') y'Cuz'Ow' type molecules can be created.

【００１１】さらにこれを微粉末化し、再び加圧してタ
ブレット化し、本焼成をする工程を有せしめている。Further, there is provided a step of finely pulverizing this, pressurizing it again to form a tablet, and carrying out main firing.

【００１２】[0012]

【作用】本発明の新型のセラミック超電導素材はきわめ
て簡単に作ることができる。特にこれらはその出発材料
として3Nまたは4Nの純度の酸化物または炭酸塩を用い、
これをボ−ルミル、あるいは乳鉢を用いて微粉末に粉砕
し、混合する。すると、化学量論的に(A1-x Bx)yCuzOw
・(A1-X 'B'x')y'Cuz'Ow',ｘ,x',ｙ,y',z,z',w,w' のそ
れぞれの値を任意に変更、制御することができる。The new ceramic superconducting material of the present invention can be made very easily. In particular, they use oxides or carbonates of 3N or 4N purity as their starting material,
This is ground into a fine powder using a ball mill or mortar and mixed. Then stoichiometrically (A 1-x Bx) yCuzOw
・ (A 1- X'B'x ') y'Cuz'Ow', x, x ', y, y', z, z ', w, w' can be changed and controlled arbitrarily. You can

【００１３】本発明においては、かかる超電導材料を作
るのに特に高価な設備を用いなくともよいという他の特
徴も有する。Another feature of the present invention is that no particularly expensive equipment is required for producing such superconducting material.

【００１４】以下に実施例に従い、本発明を記す。The present invention will be described below with reference to examples.

【００１５】[0015]

【実施例】【Example】

「実施例１」本発明の実施例として、組成式(A1-x Bx)y
CuzOw ・(A1-X 'B'x')y'Cuz'Ow',ｘ,x',ｙ,y',z,z',w,
w' において、ＡとしてＹ、ＢとしてBa,B' としてCaを
用いた。"Example 1" As an example of the present invention, the composition formula (A 1-x Bx) y
CuzOw ・ (A 1- X'B'x ') y'Cuz'Ow', x, x ', y, y', z, z ', w,
In w ', Y was used as A, Ba was used as B, and Ca was used as B'.

【００１６】出発材料はＹ化合物として酸化イットリュ
−ム(Y2O3)，Ba化合物としてBaCO3,Ca化合物としてCaCO
3,銅化合物としてCuO を用いた。これらは高純度化学工
業株式会社より入手し、純度は99.95%またはそれ以上の
微粉末を用い、ｘ＝0.33(A:B＝1:2),x' ＝0.67(A:B＝2:
1), ｙ＝1,y'＝1,z ＝3,z'＝3,w,w'＝６〜８となるべく
選んだ。またB,B'であるBaおよびCaを1:1 とした。The starting materials are yttrium oxide (Y 2 O 3 ) as the Y compound, BaCO 3 as the Ba compound, and CaCO as the Ca compound.
3. CuO was used as the copper compound. These are obtained from Kojundo Chemical Industry Co., Ltd., and use a fine powder with a purity of 99.95% or higher, x = 0.33 (A: B = 1: 2), x ′ = 0.67 (A: B = 2:
1), y = 1, y '= 1, z = 3, z' = 3, w, w '= 6-8. In addition, B and B which are B and B'are set to 1: 1.

【００１７】これらを十分乳鉢で混合しカプセルに封入
し、３Kg/cm2の荷重を加えてタブレット化( 大きさ10mm
φ×3mm)した。さらに酸化性雰囲気、例えば大気中で50
0 〜1000℃、例えば700 ℃で８時間加熱酸化をした。こ
の工程を仮焼成とした。These are sufficiently mixed in a mortar and encapsulated, and a tablet is formed by applying a load of 3 kg / cm 2 (size: 10 mm
φ x 3 mm). Furthermore, in an oxidizing atmosphere, for example, in the atmosphere, 50
It was heated and oxidized at 0 to 1000 ° C., for example 700 ° C., for 8 hours. This process was pre-baked.

【００１８】次にこれを粉砕し、乳鉢で混合した。そし
てその粉末の平均粉半径が10μｍ以下の大きさとなるよ
うにした。Next, this was crushed and mixed in a mortar. The average powder radius of the powder was set to 10 μm or less.

【００１９】さらにこれをカプセルに封入し50Kg/cm2の
圧力でタブレットに加圧して成型した。この加圧と同時
に加熱をするホットプレス方式を採用してもよい。Further, this was enclosed in a capsule and pressed into a tablet at a pressure of 50 Kg / cm 2 for molding. You may employ | adopt the hot press system which heats simultaneously with this pressurization.

【００２０】次に500 〜1000℃、例えば900 ℃の酸化物
雰囲気、例えば大気中で酸化して、本焼成を10〜50時
間、例えば15時間行った。すると新型の構造がより顕著
に観察されるようになった。Next, the main calcination was carried out for 10 to 50 hours, for example 15 hours, by oxidizing in an oxide atmosphere at 500 to 1000 ° C., for example 900 ° C., for example, air. Then, the new structure became more prominently observed.

【００２１】この試料を用いて固有抵抗と温度との関係
を調べた。すると最高温度が得られたものとしてのTcオ
ンセット( 超電導の始まる温度)として104K, Tco(電気
抵抗の零となる温度) として93K を観察することができ
た。Using this sample, the relationship between specific resistance and temperature was investigated. Then, it was possible to observe Tc onset (temperature at which superconductivity starts) 104K and Tco (temperature at which electric resistance becomes zero) 93K as the maximum temperature was obtained.

【００２２】「実施例２」この実施例として、Ａとして
Ybの酸化物を混合した。ＢとしてBa、B'としてSrを用い
y:y'＝1:1 とした。出発材料は酸化イッテルビュ−ムお
よび酸化イットリュ−ム、BaとしてBaCO3 、SrとしてSr
2O3 また銅化合物としてCuO を用いた。その他は実施例
１と同様である。[Embodiment 2] As this embodiment, as A
The oxide of Yb was mixed. Ba as B and Sr as B '
y: y '= 1: 1. The starting materials are ytterbium oxide and yttrium oxide, BaCO 3 as Ba and Sr as Sr.
2 O 3 CuO was used as the copper compound. Others are the same as in the first embodiment.

【００２３】Tcオンセットとして109K, Tco として87K
を観察することができた。109K as Tc onset, 87K as Tco
Was able to be observed.

【００２４】「実施例３」実施例１において、B,B'とし
てBa,Sr に加えB'' としてCaCO3 を20〜30％加えた。す
るとTcオンセットをさらに３〜５K も向上させることが
できた。Example 3 In Example 1, 20 to 30% of CaCO 3 was added as B ″ in addition to Ba and Sr as B and B ′. Then, Tc onset could be improved by 3-5K.

【００２５】本発明において、イットリュ−ム族(Y,Eu,
Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Sc,)の元素およびその他のラ
ンタノイドを酸化物または炭酸塩とし、それらを出発材
料として用いて複合材料セラミックスとしても有効であ
る。特にこれらより選ばれた材料を(A1-x Bx)yCuzOw ・
(A1-X 'B'x')y'Cuz'Ow' で示される一般式のB,B'の一部
に加えることはTcをさらに5 〜10K も向上させ得る効果
があった。In the present invention, the yttrium group (Y, Eu,
Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, and other elements and other lanthanoids are used as oxides or carbonates, and they are also effective as composite ceramics by using them as starting materials. In particular, materials selected from these (A 1-x Bx) yCuzOw
(A 1-X 'B'x') y'Cuz'Ow 'was added to a part of B and B'in the general formula, and Tc could be further improved by 5 to 10K.

【００２６】本発明はその他の材料であるＢとして、M
g,Be を用い得る。その概要は実施例１と概略同様であ
る。In the present invention, as another material, B, M
g, Be can be used. The outline is similar to that of the first embodiment.

【００２７】[0027]

【発明の効果】本発明により、これまでまったく不可能
とされていた、液体窒素温度（77K ）以上で動作するセ
ラミック超電導体を作ることができるようになった。According to the present invention, it has become possible to manufacture a ceramic superconductor which operates at a liquid nitrogen temperature (77 K) or higher, which has been impossible at all.

【００２８】本発明において仮焼成をした後に微粉末化
する工程により、初期状態でのそれぞれの出発材料の化
合物を到達材料、即ち(A1-x Bx)yCuzOw ・(A1-X' B'x')
y'Cuz'Ow'で示される材料を含む化合物とするものであ
る。In the present invention, the compound of each starting material in the initial state is converted into a reaching material, that is, (A 1-x Bx) yCuzOw · (A 1-X 'B' by the step of pulverizing after calcination. x ')
It is a compound containing a material represented by y'Cuz'Ow '.

【００２９】さらにこの到達材料の化合物における分子
構造内で銅の層構造をよりさせやすくするため、原子周
期律表における２ａ、３ａの元素を複数個混合させた。
かくして最終完成化合物中に、新型の構造がより顕著に
観察されるようになり、ひいてはTcオンセット、Tco を
より高温化できるものと推定される。Further, in order to make the layer structure of copper easier in the molecular structure of the compound of this reaching material, a plurality of elements 2a and 3a in the atomic periodic table were mixed.
Thus, it is presumed that a new type of structure will be more prominently observed in the final finished compound, and that Tc onset and Tco can be further increased in temperature.

【００３０】また本発明の分子式で示される超電導セラ
ミックスはその超電導のメカニズムとして、銅の酸化物
が構造において層構造を有し、その層構造も一分子内で
２層構成を有し、その層内をキャリアが超電導をしてい
るものである。The superconducting ceramics represented by the molecular formula of the present invention has a superconducting mechanism in which copper oxide has a layered structure, and the layered structure also has a two-layer structure within one molecule. The carrier is superconducting inside.

【００３１】本発明の実施例は、タブレットにしたもの
である。しかしタブレットにするのではなく、仮焼成ま
たは本焼成の後の粉末を溶媒にとかし、基板等にその溶
液をコ−ティングをし、これを酸化性雰囲気で焼成し、
さらにその後本焼成をすることによって、薄膜の超電導
セラミックスとすることも可能である。The embodiment of the present invention is a tablet. However, instead of making it into a tablet, the powder after calcination or main calcination is dissolved in a solvent, the solution is coated on a substrate or the like, and this is baked in an oxidizing atmosphere,
It is also possible to obtain a thin-film superconducting ceramic by further performing main firing thereafter.

【００３２】本発明により超電導体を容易に低価格で作
ることができるようになった。According to the present invention, a superconductor can be easily manufactured at low cost.

Claims (1)

【特許請求の範囲】 【請求項１】銅の酸化物が構造において層構造を有し、
その構造も１分子内で２層構成を有し、その層内をキャ
リアが超電導しており、その結果、液体窒素温度（77K)
以上で超電導性を有することを特徴とする超電導セラミ
ックス。Claim: What is claimed is: 1. A copper oxide has a layered structure in the structure,
The structure also has a two-layer structure within one molecule, and the carriers are superconducting in that layer, resulting in a liquid nitrogen temperature (77K).
Superconducting ceramics characterized by having superconductivity as described above.
JP3094815A 1991-04-01 1991-04-01 Superconducting ceramics Pending JPH0517203A (en)

Priority Applications (1)

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JP3094815A JPH0517203A (en) 1991-04-01 1991-04-01 Superconducting ceramics

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Application Number Priority Date Filing Date Title
JP3094815A JPH0517203A (en) 1991-04-01 1991-04-01 Superconducting ceramics

Related Parent Applications (1)

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JP62072483A Division JP2588399B2 (en) 1987-03-25 1987-03-25 Superconducting ceramics

Publications (1)

Publication Number Publication Date
JPH0517203A true JPH0517203A (en) 1993-01-26

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
JP3094815A Pending JPH0517203A (en) 1991-04-01 1991-04-01 Superconducting ceramics

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Country Link
JP (1) JPH0517203A (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63225572A (en) * 1987-03-13 1988-09-20 Tokyo Univ Superconductive base material
JPS63225531A (en) * 1987-03-13 1988-09-20 Nippon Telegr & Teleph Corp <Ntt> Oxide superconductive material

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63225572A (en) * 1987-03-13 1988-09-20 Tokyo Univ Superconductive base material
JPS63225531A (en) * 1987-03-13 1988-09-20 Nippon Telegr & Teleph Corp <Ntt> Oxide superconductive material

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