JP2563352B2 - Method of manufacturing a composite superconductors - Google Patents

Method of manufacturing a composite superconductors

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JP2563352B2
JP2563352B2 JP16504387A JP16504387A JP2563352B2 JP 2563352 B2 JP2563352 B2 JP 2563352B2 JP 16504387 A JP16504387 A JP 16504387A JP 16504387 A JP16504387 A JP 16504387A JP 2563352 B2 JP2563352 B2 JP 2563352B2
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powder
superconductor
method
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composite
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JPS6410518A (en )
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昌子 中橋
博光 竹田
久士 芳野
隆夫 鈴木
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株式会社東芝
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    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/60Superconducting electric elements or equipment or power systems integrating superconducting elements or equipment
    • Y02E40/64Superconducting transmission lines or power lines or cables or installations thereof
    • Y02E40/641Superconducting transmission lines or power lines or cables or installations thereof characterised by their form
    • Y02E40/644Multifilaments embedded in normal conductors

Description

【発明の詳細な説明】 [発明の目的] (産業上の利用分野) 本発明は、複合超電導体の製造方法に関する。 DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION (INDUSTRIAL FIELD) The present invention relates to a method of manufacturing a composite superconductor.

(従来の技術) 近年、Ba−La−Cu−O系の層状ペロブスカイト型の酸化物が高い臨界温度を有する可能性のあることが発表されて以来、各所で酸化物超電導体の研究が行われている(Z.Phys.B Condensed Matter 64,189−193(198 (Prior Art) In recent years, since it was announced that the Ba-La-Cu-O based oxide having a layered perovskite type with possibility of having a high critical temperature, studies of the oxide superconductor is carried out in various places and that (Z.Phys.B Condensed Matter 64,189-193 (198
6))。 6)). その中でもY−Ba−Cu−O系で代表される酸素欠陥を有する欠陥ペロブスカイト型(ABa 2 Cu 3 O 7−δ Defect perovskite also have oxygen defects typified by Y-Ba-Cu-O system in which (ABa 2 Cu 3 O 7- δ)
(δは酸素欠陥を表し通常1以下の数、Aは、Y、La、 ([Delta] is usually 1 or less number represents an oxygen defect, A is, Y, La,
Sc、Nd、Sm、Eu、Gd、Dy、Ho、Er、Tm、YbおよびLuから選ばれた少なくとも1種の元素、Baの一部はSr等で置換可能)の酸化物超電導体は、臨界温度が90K以上と液体窒素以上の高い温度を示すため非常に有望な材料として注目されている(Phys.Rev.Lett.Vol.58 No.9,908−91 Sc, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, at least one element selected from Yb, and Lu, a portion of Ba may be substituted with Sr, etc.) oxide superconductor, the critical temperature has been attracting attention as a very promising material for indicating the temperature or higher and high above liquid nitrogen 90K (Phys.Rev.Lett.Vol.58 No.9,908-91
0)。 0).

この酸化物超電導体は、結晶性の酸化物であって、その結晶のC面に沿って超電導電流が流れるため、この酸化物超電導体粉末を単に焼結させただけでは、結晶の配列方向がランダムになり、所望の電流密度が得られないという問題があった。 The oxide superconductor is a crystalline oxide, for superconducting current flows along the C plane of the crystal, only simply by sintering the oxide superconductor powder, the arrangement direction of the crystal is random, there is a problem that a desired current density can not be obtained.

(発明が解決しようとする問題点) このように、酸化物超電導体は、この酸化物超電導体はその結晶のC面に沿って超電導電流が流れるため、所望の電流密度を得ることが困難であった。 In (invention Problems to be solved) Thus, the oxide superconductor, the oxide superconductor for the superconducting current flows along the C plane of the crystal, it is difficult to obtain a desired current density there were.

本発明は、このような従来の難点を解消すべくなされたもので、臨界温度および臨界電流密度が高い超電導体の製造方法を提供することを目的とする。 The present invention has been achieved to solve such conventional difficulties, and an object thereof is to provide a manufacturing method of the critical temperature and critical current density is high superconductor.

[発明の構成] (問題点を解決するための手段) すなわち、本発明の複合超電導体の製造方法は、常電導金属粉末と酸化物超電導体粉末とからなる混合粉末を、耐熱性の容器内に充填して加熱溶融させ、次いで温度勾配を設けて徐冷し、所定の方向性をもたせて凝固させることを特徴としている。 [Configuration of the Invention (Means for Solving the Problems) In other words, the production method of the composite superconductor of the present invention, a mixed powder consisting of a normal-conducting metal powder and the oxide superconductor powder, heat-resistant vessel by filling heated and melted, and then gradually cooled to provide a temperature gradient is characterized by solidifying and imparted a predetermined direction to.

本発明の製造方法に用いる常電導金属粉末としては、 The normal-conducting metal powder used in the production method of the present invention,
任意の公知の常電導金属粉末が使用可能であるが、特に、Ag粉末、Cu粉末、またはAgとCuの混合粉末が適している。 Although any of the known normal-conducting metal powder can be used, in particular, Ag powder, Cu powder or mixed powder of Ag and Cu, is suitable.

また、本発明の製造方法に用いる酸化物超電導体粉末としては、平均粒径が1〜5μmである、希土類元素を含有しペロブスカイト構造を有する酸化物超伝導体の粉末を用いることが実用上好ましい。 As the oxide superconductor powder used in the production method of the present invention, an average particle size of 1 to 5 [mu] m, it is practically preferable to use a powder of the oxide superconductor having a perovskite structure and contains a rare earth element .

ここでいう希土類元素を含有しペロブスカイト型構造を有する酸化物超電導体は、超電導状態を実現できるものであればよく、ABa 2 Cu 3 O 7−δ系(δは酸素欠陥を表し通常1以下の数、Aは、Y、La、Sc、Nd、Sm、Eu、G Oxide superconductor having a content by perovskite structure of rare earth element referred to here, as long as it can realize the superconducting state, ABa 2 Cu 3 O 7- δ type ([delta] Normal 1 below represents an oxygen defect the number, A is, Y, La, Sc, Nd, Sm, Eu, G
d、Dy、Ho、Er、Tm、YbおよびLuから選ばれた少なくとも1種の元素、Baの一部はSr等で置換可能)等の酸素欠陥を有する欠陥ペロブスカイト型、Sr−La−Cu−O系等の層状ペロブスカイト型等の広義のペロブスカイト型を有する酸化物が例示される。 d, Dy, Ho, Er, Tm, at least one element selected from Yb, and Lu, defect perovskite some Ba with oxygen defects substitutable), etc. In or Sr, Sr-La-Cu- oxide having a broad perovskite layered perovskite type or the like of the O type, and the like. また希土類元素も、広義の定義とし、Sc、Yおよびランタン系を含むものとする。 The rare earth element is also a broad definition is intended to include Sc, Y and lanthanide.
代表的な系としてY−Ba−Cu−O系のほかに、Yを、E In addition to the Y-Ba-Cu-O system as a typical system, the Y, E
u、Dy、Ho、Er、Tm、Yb、Lu等の希土類で置換した系、S u, Dy, Ho, Er, Tm, Yb, the system was replaced with rare earth Lu etc., S
c−Ba−Cu−O系、Sr−La−Cu−O系、さらにSrをBa、C c-Ba-Cu-O system, Sr-La-Cu-O system, further Sr Ba, C
aで置換した系等が挙げられる。 System or the like obtained by substituting a and the like.

次に本発明の製造方法について説明する。 Next will be described a manufacturing method of the present invention.

まず、Y、Ba、Cuなどのペロブスカイト型酸化物超電導体の構成元素を十分混合する。 First, Y, Ba, and mix well the constituent elements of the perovskite type oxide superconductors, such as Cu. 混合の際には、Y 2 O 3 During mixing, Y 2 O 3,
Eu 2 O 3 、BaO、CuO等の酸化物を原料として用いることできる。 Eu 2 O 3, BaO, an oxide such as CuO can be used as a raw material. また、これらの酸化物のほかに、焼成後酸化物に転化する炭素塩、硝酸塩、水酸化物等の化合物を用いてもよい。 Also, In addition to these oxides, carbonates converted to calcined oxides, nitrates, may be a compound such as hydroxide. さらには、共沈法等で得たシュウ酸塩等を用いてもよい。 Further, it may be used oxalic acid salt obtained in coprecipitation method. ペロブスカイト型酸化物超電導体を構成する元素は、基本的に化学量論比の組成となるように混合するが、多少製造条件等との関係等でずれていても差支えない。 Elements constituting the perovskite-type oxide superconductor is mixed so as to have the composition of essentially stoichiometric ratio, no problem be shifted slightly in the relationships of the manufacturing conditions. 例えば、Y−Ba−Cu−O系ではY 1molに対しBa 2 For example, Ba 2 to Y 1 mol in Y-Ba-Cu-O system
mol、Cu 3molが標準組成であるが、実用上はY 1molに対して、Ba2±0.6mol、Cu3±0.2mol程度のずれは問題ない。 mol, although Cu 3 mol is standard composition, practical for Y 1 mol, Ba2 ± 0.6 mol, a deviation of about Cu3 ± 0.2 mol is no problem.

前述の原料を混合した後、仮焼、粉砕し所望の形状にした後、850〜980℃程度で焼成する。 After mixing the aforementioned raw material, after the calcination, grinding and the desired shape and fired at about 850 to 980 ° C.. 仮焼は必ずしも必要ではない。 Calcination is not always necessary. 仮焼、焼成は十分な酸素が供給できるような酸素含有雰囲気中で行うことが好ましい。 Calcination, calcination is preferably carried out in an oxygen-containing atmosphere, such as sufficient oxygen can be supplied.

所望の形状に焼成した後、酸素中で加熱処理、または After sintering the desired shape, heat treatment in oxygen, or
300℃程度まで徐冷することにより、超電導特性を向上させることができる。 By slowly cooling to about 300 ° C., it is possible to improve the superconducting properties. 前記加熱処理は通常300〜700℃程度で行う。 The heat treatment is carried out at usually about 300 to 700 ° C..

このようにして得られた酸化物超電導体は、酸素欠陥δを有する酸素欠陥型ペロブスカイト型構造(LnBa 2 Cu 3 The thus obtained oxide superconductor, oxygen deficiency type perovskite structure having oxygen vacancy δ (LnBa 2 Cu 3
O 7−δ (δは通常1以下))となる。 O 7-δ (δ is usually 1 or less)) and a. なおCuの一部をT It should be noted that the part of the Cu T
i、V、Cr、Mn、Fe、Co、Ni、Zn等で置換することもできる。 It i, V, Cr, Mn, Fe, Co, Ni, also be replaced with Zn and the like.

置換量は、超電導特性を低下させない程度の範囲で適宜設定可能であるが、あまり多量の置換は超電導特性を低下させてしまうので80mol%以下、さらに実用上は20m Amount of substitution can be suitably set within a range as not to lower the superconducting properties, so less 80 mol% because a large amount of substitution would reduce the superconducting properties, yet practically 20m
ol%以下程度までとする。 And to the extent below ol%.

次に、この酸化物超電導体の焼成体をボールミル等の公知の手段により粉砕する。 Next, the sintered body of the oxide superconductor is pulverized by a known means such as a ball mill. このとき、酸化物超電導体の焼成体はへき開面から分割されて微粉末となる。 In this case, the sintered body of the oxide superconductor is a fine powder is divided from the cleavage plane. 粉砕は、微粉末の平均粒径が1〜5μm程度、直径対厚さの比が3〜5となるまで行うことが望ましい。 Milling is preferably carried out until the average particle size of about 1~5μm fine powder, the ratio of diameter to thickness becomes 3 to 5. なお、必要に応じて、粉砕した粉末を前記の範囲となるように分級して用いてもよい。 If necessary, the ground powder may be used and classified to be in the range of the.

次に、この酸化物超電導体粉末と、前述した常電導金属粉末とを、1:1〜1:10の混合比で混合し、この混合粉末を、一端に冷却機構を有するセラミック管、耐熱金属管のような耐熱性の容器内に充填し、この耐熱性の容器を加熱して、容器内の混合原料のみを溶融させ、しかる後通電方向に10℃/cm程度の温度勾配をつけて一端側から100〜300℃/時間程度の冷却速度で徐冷する。 Next, the the oxide superconductor powder, and a normal-conducting metal powder described above, 1: 1 to 1: mixing at 10 mixing ratio, the mixed powder, a ceramic tube having a cooling mechanism at one end, a refractory metal filled into heat-resistant vessel such as a tube, and heating the heat-resistant container, to melt the only mixed raw material in the vessel, with a temperature gradient of approximately 10 ° C. / cm and thereafter energizing direction end slow cooling at a cooling rate of about 100 to 300 ° C. / time from the side.

このように、通電方向に温度勾配をつけて徐冷することにより、常電導金属を母地とし、その中に多数の酸化物超電導体が通電方向に繊維状に配列された複合超電導体を得ることができる。 Thus, by slow cooling with a temperature gradient in the energizing direction, the normal-conducting metal as a base fabric, a number of oxide superconductor to obtain a composite superconductor arranged in fibrous energizing direction therein be able to.

(作 用) 本発明の複合超電導体の製造方法では、常電導金属粉末と酸化物超電導体粉末とからなる混合粉末を耐熱性の容器内に充填して加熱溶融させ、次いで温度勾配を設けて徐冷し、所定の方向性をもたせて凝固させるので、常電導金属の母地の中に、酸化物超電導体が電流を流すべき方向と平行に繊維状に連続して結晶化され、高い電流密度を得ることができる。 The method for producing a composite superconductor (work for) the present invention, a mixed powder consisting of a normal-conducting metal powder and the oxide superconductor powder was heated and melted and filled in the heat resistance of the container, then provided the temperature gradient gradually cooled, since the coagulated imparted a predetermined direction, in the mother locations normal-conducting metal, is crystallized continuously in the fibrous parallel to the direction in which the oxide superconductor current flow, high current it can be obtained density.

(実施例) 以下、本発明の実施例について説明する。 (Example) Hereinafter, a description will be given of an embodiment of the present invention.

実施例 本発明に用いる酸化物超電導体粉末の原料として、Ba As a raw material of the oxide superconductor powder used in the embodiment the present invention, Ba
CO 3粉末2mol%、Y 2 O 3粉末0.5mol%、CuO粉末3mol%を十分混合して、900℃で48時間焼成した後粉砕した。 CO 3 powder 2mol%, Y 2 O 3 powder 0.5 mol%, sufficiently mixing CuO powder 3 mol%, was pulverized after calcination for 48 hours at 900 ° C.. この粉末原料を大気中で800℃で24時間焼成して反応させ、 The powder raw material is reacted by firing for 24 hours at 800 ° C. in air,
酸素空席に酸素を導入した後、ボールミルを用いて粉砕し、分級して、平均粒径2μm、直径対厚さの比が1〜 After the introduction of oxygen into oxygen vacancy, a ball mill was triturated with and classified, the average particle diameter of 2 [mu] m, the ratio of diameter to thickness 1
5のペロブスカイト構造を有する酸化物超電導体粉末を得た。 5 was obtained oxide superconductor powder having a perovskite structure.

次に、この酸化物超電導体粉末50mol%に、平均粒径が100μmである銅粉末50mol%を加えて、十分に混合した後、この混合原料を、一端に銅板からなる水冷機構を有する外径20mm、内径15mm、長さ200mmのアルミナ管に充填し、他端にアルミナの栓をして通気孔を残してロウ付した。 Next, the oxide superconductor powder 50 mol%, having an average particle diameter by the addition of copper powder 50 mol% is 100 [mu] m, and mixed thoroughly, the mixed raw material, the outer diameter with a water cooling system consisting of a copper plate on one end 20 mm, an inner diameter of 15 mm, was filled in an alumina tube length 200 mm, and the alumina plug was subjected wax leaving a vent at the other end.

このアルミナ管を、外部ヒータにより1200℃で0.5時間加熱して管内の混合原料を溶融させた後、外部ヒータによる加熱を行ったままの状態で、アルミナ管の一端にある銅板を20℃に冷却し管の長手方向に0.05mm/sの速度で移動させて外部ヒータから徐々に外し、常温まで冷却させた後アルミナ管を除去して複合超電導体を得た。 Cooling the alumina tube, after melting the mixed raw material in the tube was heated at 1200 ° C. 0.5 hours by an external heater, in a state in which heating was carried out by an external heater, the copper plate at one end of the alumina tube 20 ° C. longitudinal and tube is moved at a speed of 0.05 mm / s and gradually removed from the external heater to obtain a composite superconductor by removing the alumina tube after cooling to room temperature.

この複合超電導体の長さ方向の臨界温度は110Kであり、臨界電流密度は1500A/cm 2であった。 The critical temperature in the longitudinal direction of the composite superconductor is 110K, the critical current density was 1500A / cm 2.

また、この複合超電導体の縦断面を観察したところ、 Further, observation of the longitudinal section of the composite superconductor,
銅の母地の中に、酸化物超電導体が長手方向に繊維状に連続して結晶化していることが確認された。 Some mother locations copper oxide superconductor it was confirmed that the crystallized continuously to fibrous in the longitudinal direction.

[発明の効果] 以上の実施例からも明らかなように、本発明の製造方法によれば、臨界温度および臨界電流密度の高い複合超電導体を得ることができる。 As apparent from the above embodiment [Effect of the Invention] According to the production method of the present invention, it is possible to obtain a high composite superconductor critical temperature and critical current density.

───────────────────────────────────────────────────── フロントページの続き (72)発明者 芳野 久士 神奈川県川崎市幸区小向東芝町1 株式 会社東芝総合研究所内 (56)参考文献 特開 昭63−292529(JP,A) 特開 昭63−301424(JP,A) 特開 昭64−21034(JP,A) ────────────────────────────────────────────────── ─── of the front page continued (72) inventor Yoshino Hisashi Kawasaki-shi, Kanagawa-ku, Saiwai Komukaitoshiba-cho 1 stock company Toshiba in the Institute (56) reference Patent Sho 63-292529 (JP, a) JP Akira 63-301424 (JP, A) JP Akira 64-21034 (JP, A)

Claims (5)

    (57)【特許請求の範囲】 (57) [the claims]
  1. 【請求項1】常電導金属粉末と酸化物超電導体粉末とからなる混合粉末を耐熱性の容器内に充填して加熱溶融させ、次いで温度勾配を設けて徐冷し、所定の方向性をもたせて凝固させることを特徴とする複合超電導体の製造方法。 1. A melted by heating by filling a mixed powder consisting of a normal-conducting metal powder and the oxide superconductor powder in heat resistance of the container, and then gradually cooled to provide a temperature gradient, remembering predetermined direction method for producing a composite superconductor, characterized in that solidifying Te.
  2. 【請求項2】常電導金属粉末は、Agおよび/またはCuの粉末であることを特徴とする特許請求の範囲第1項記載の複合超電導体の製造方法。 2. A normal-conducting metal powder, method for producing a composite superconductor Claims preceding claim which is a powder of Ag and / or Cu.
  3. 【請求項3】酸化物超伝導体粉末は、希土類元素を含有するペロブスカイト型の超電導体であることを特徴とする特許請求の範囲第1項または第2項記載の複合超電導体の製造方法。 Wherein the oxide superconductor powder, a manufacturing method of Patent claim 1, wherein or composite superconductors of the second term, wherein it is a superconductor of the perovskite type containing a rare earth element.
  4. 【請求項4】酸化物超伝導体粉末が、Ln元素(Lnは、 4. The oxide superconductor powder, Ln element (Ln is
    Y、La、Sc、Nd、Sm、Eu、Gd、Dy、Ho、Er、Tm、YbおよびLuから選ばれた少なくとも1種の元素)、BaおよびCu Y, La, Sc, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, at least one element selected from Yb, and Lu), Ba and Cu
    を原子比で実質的に1:2:3の割合いで含有することを特徴とする特許請求の範囲第1項ないし第3項のいずれか1項記載の複合超電導体の製造方法。 Substantially 1 atomic ratio: 2: method for producing a composite superconductor according to any one of Claims first term to the third term, characterized in that it contains a proportion physicians 3.
  5. 【請求項5】酸化物超伝導体粉末は、LnBa 2 Cu 3 O 7−δ 5. The oxide superconductor powder, LnBa 2 Cu 3 O 7- δ
    (δは酸素欠陥を表す)で表される酸素欠陥型ペロブスカイト型構造を有することを特徴とする特許請求の範囲第1項ないし第4項のいずれか1項記載の複合超電導体の製造方法。 Method for producing a composite superconductor according to any one of Claims first term to the fourth term, characterized in that it comprises a ([delta] represents an oxygen deficiency) the oxygen defect type perovskite structure represented by.
JP16504387A 1987-07-01 1987-07-01 Method of manufacturing a composite superconductors Expired - Lifetime JP2563352B2 (en)

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DE68908569T2 (en) * 1988-01-11 1993-12-23 American Telephone & Telegraph A method for producing a ceramic superconductor body.
DE3805954C1 (en) * 1988-02-25 1989-09-28 Max-Planck-Gesellschaft Zur Foerderung Der Wissenschaften Ev, 3400 Goettingen, De
JPH02206504A (en) * 1989-02-03 1990-08-16 Koujiyundo Kagaku Kenkyusho:Kk Work piece of superconductive material

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