JP6012658B2 - Oxide superconducting wire and manufacturing method thereof - Google Patents

Oxide superconducting wire and manufacturing method thereof Download PDF

Info

Publication number
JP6012658B2
JP6012658B2 JP2014075439A JP2014075439A JP6012658B2 JP 6012658 B2 JP6012658 B2 JP 6012658B2 JP 2014075439 A JP2014075439 A JP 2014075439A JP 2014075439 A JP2014075439 A JP 2014075439A JP 6012658 B2 JP6012658 B2 JP 6012658B2
Authority
JP
Japan
Prior art keywords
layer
oxide superconducting
protective layer
superconducting wire
protective
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.)
Active
Application number
JP2014075439A
Other languages
Japanese (ja)
Other versions
JP2015198009A (en
Inventor
正樹 大杉
正樹 大杉
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.)
Fujikura Ltd
Original Assignee
Fujikura 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 Fujikura Ltd filed Critical Fujikura Ltd
Priority to JP2014075439A priority Critical patent/JP6012658B2/en
Publication of JP2015198009A publication Critical patent/JP2015198009A/en
Application granted granted Critical
Publication of JP6012658B2 publication Critical patent/JP6012658B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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

  • Superconductors And Manufacturing Methods Therefor (AREA)

Description

本発明は、酸化物超電導線材とその製造方法に関する。   The present invention relates to an oxide superconducting wire and a method for producing the same.

ＲＥ−１２３系（ＲＥＢａ２Ｃｕ３Ｏ（７−ｘ）：ＲＥは希土類元素の１種または２種以上）等の酸化物超電導体は、液体窒素温度（７７Ｋ）を超える温度（例えば９０Ｋ前後）で超電導特性を示し、強磁界内でも比較的高い臨界電流密度を維持することができるため、超電導コイルや超電導電力ケーブルなどの応用開発が進められている。
この種の酸化物超電導体を用いた酸化物超電導線材は、ハステロイ（登録商標）などの耐熱合金テープの基材上にイオンビームアシスト法により結晶配向性を揃えた中間層を形成し、その表面に酸化物超電導層を成膜し、更にその表面にＡｇなどからなる保護層を形成することで製造されている。 The oxide superconductor such as RE-123 series (REBa 2 Cu 3 O (7-x) : RE is one or more of rare earth elements) has a temperature exceeding the liquid nitrogen temperature (77 K) (for example, around 90 K). Since it exhibits superconducting characteristics and can maintain a relatively high critical current density even in a strong magnetic field, applications such as superconducting coils and superconducting power cables are being developed.
An oxide superconducting wire using this type of oxide superconductor forms an intermediate layer with uniform crystal orientation on the base material of a heat-resistant alloy tape such as Hastelloy (registered trademark) by the ion beam assist method. An oxide superconducting layer is formed on the surface, and a protective layer made of Ag or the like is further formed on the surface thereof.

酸化物超電導線材の一例として、図５に示すように、基材上に中間層を介し酸化物超電導層と保護層を形成して酸化物超電導積層体１００を構成し、酸化物超電導積層体の表裏面にはんだ層１０１を介しＣｕの金属箔からなる安定化層１０２を一体化した酸化物超電導線材１０３が開示されている（特許文献１参照）。   As an example of the oxide superconducting wire, as shown in FIG. 5, an oxide superconducting laminate 100 is formed by forming an oxide superconducting layer and a protective layer on a substrate via an intermediate layer. An oxide superconducting wire 103 is disclosed in which a stabilization layer 102 made of a Cu metal foil is integrated on the front and back surfaces via a solder layer 101 (see Patent Document 1).

また、酸化物超電導線材等の高温超電導線材を用いて超電導コイルを作製した場合、磁力によるフープ力や、樹脂含浸するための樹脂と高温超電導線材との間の熱収縮率差により高温超電導線材内部に応力が作用し、高温超電導線材内部にき裂を生じる問題がある。
このため、基材上に中間層を介し酸化物超電導層を形成した図６に示す酸化物超電導積層体１００を構成し、この酸化物超電導積層体１００の周面をＣｕの金属箔などの金属テープ１０５で横断面Ｃ字型に覆い、金属テープ１０５の内面側に設けたはんだ層１０６により一体化した構造の高温超電導線材１０７が知られている（特許文献２参照）。 In addition, when a superconducting coil is manufactured using a high-temperature superconducting wire such as an oxide superconducting wire, the inside of the high-temperature superconducting wire due to a hoop force due to magnetic force or a difference in thermal shrinkage between the resin for impregnation with the resin and the high-temperature superconducting wire There is a problem in that stress acts on the metal and cracks occur inside the high-temperature superconducting wire.
For this reason, the oxide superconducting laminate 100 shown in FIG. 6 in which the oxide superconducting layer is formed on the base material via the intermediate layer is constituted, and the peripheral surface of the oxide superconducting laminate 100 is made of a metal such as a Cu metal foil. A high temperature superconducting wire 107 having a structure that is covered with a tape 105 in a C-shaped cross section and integrated by a solder layer 106 provided on the inner surface side of the metal tape 105 is known (see Patent Document 2).

特表２００３−５０５８４８号公報Special table 2003-505848 gazette 特開２０１１−００３４９４号公報JP 2011-003494 A

特許文献１、２に記載の構造によれば、酸化物超電導積層体１００とこれを覆う安定化層１０２との接合、並びに、酸化物超電導積層体１００と金属テープ１０５との接合をいずれもはんだ層１０１、１０６により行っている。このため、酸化物超電導層側に設けられている保護層と安定化層との間に微細な隙間が生じていると、超電導線材に力が作用した場合、微細な隙間部分とその周囲に応力が集中し、酸化物超電導層とその周囲の層との界面部分において剥離を生じる問題があった。
基材と中間層との間、あるいは、保護層と安定化層との間において剥離が生じる場合は、直接、酸化物超電導層が損傷する訳ではないので、通電時の事故に直結しないが、酸化物超電導層とそれに接する層との界面において剥離が生じると、超電導体としての通電経路そのものが損傷するおそれがあり、通電時の大きな問題となるおそれがある。 According to the structures described in Patent Documents 1 and 2, both the joining of the oxide superconducting laminate 100 and the stabilization layer 102 covering the oxide superconducting laminate 100 and the joining of the oxide superconducting laminate 100 and the metal tape 105 are both soldered. Layers 101 and 106 are used. For this reason, if a fine gap is generated between the protective layer and the stabilization layer provided on the oxide superconducting layer side, if a force acts on the superconducting wire, stress is applied to the fine gap and its surroundings. There is a problem that peeling occurs at the interface portion between the oxide superconducting layer and the surrounding layers.
When peeling occurs between the base material and the intermediate layer or between the protective layer and the stabilization layer, the oxide superconducting layer is not directly damaged. If delamination occurs at the interface between the oxide superconducting layer and the layer in contact with the oxide superconducting layer, the energization path itself as the superconductor may be damaged, which may be a serious problem during energization.

本発明者は、応力が作用して積層構造のいずれかに層間剥離を生じたとしても、酸化物超電導層そのものが損傷しないようにできる構造について種々研究した結果、本願発明に到達した。   As a result of various studies on the structure capable of preventing the oxide superconducting layer itself from being damaged even if the stress acts to cause delamination in any of the laminated structures, the inventors have arrived at the present invention.

本発明は、以上のような従来の実情に鑑みなされたものであり、酸化物超電導層に接している層の部分で層間剥離を生じることがなく、酸化物超電導層から離れた層の部分に剥離を誘導できる構造を採用し、応力が作用した場合であっても酸化物超電導層に損傷を生じ難い構造を採用した酸化物超電導線材およびその製造方法の提供を目的とする。   The present invention has been made in view of the conventional situation as described above, and does not cause delamination in the layer portion in contact with the oxide superconducting layer, and in a layer portion away from the oxide superconducting layer. An object of the present invention is to provide an oxide superconducting wire that employs a structure that can induce delamination and that does not easily damage an oxide superconducting layer even when stress is applied, and a method for manufacturing the same.

前記課題を解決するため、基材の主面上に中間層および酸化物超電導層が形成された酸化物超電導積層体と、前記酸化物超電導積層体の外周に形成された保護層と、前記保護層上に形成された安定化層と、を備え、前記保護層が、少なくとも前記酸化物超電導層の主面を覆うように形成されたＡｇ又はＡｇ合金からなる第１の保護層と、少なくとも前記基材の主面とは反対側の裏面を覆うように形成されたＡｇまたはＡｇ合金からなる第２の保護層を含み、前記安定化層が、前記第１の保護層と前記第２の保護層の少なくとも一部を覆って設けられ、前記酸化物超電導層と前記中間層の間の剥離強度より、前記基材と前記第２の保護層の間の剥離強度が小さくされたことを特徴とする。   In order to solve the above problems, an oxide superconducting laminate in which an intermediate layer and an oxide superconducting layer are formed on a main surface of a substrate, a protective layer formed on the outer periphery of the oxide superconducting laminate, and the protection A first protective layer made of Ag or an Ag alloy formed so as to cover at least the main surface of the oxide superconducting layer, and a stabilizing layer formed on the layer. A second protective layer made of Ag or an Ag alloy formed so as to cover the back surface opposite to the main surface of the substrate, wherein the stabilizing layer includes the first protective layer and the second protective layer Provided to cover at least a part of the layer, wherein the peel strength between the base material and the second protective layer is made smaller than the peel strength between the oxide superconducting layer and the intermediate layer, To do.

酸化物超電導層と中間層との間の剥離強度よりも、基材と第２の保護層との間の剥離強度を小さくしたので、超電導コイルあるいは超電導ケーブルなどの用途に利用し、仮に応力が作用したとしても、基材と第２の保護層との界面に層間剥離を誘導することができ、酸化物超電導層とそれに隣接する層との間の層間剥離を抑制できる。このため、応力が作用した場合、基材と第２の保護層との間に層間剥離を誘導し易く、酸化物超電導層と中間層との間に層間剥離を生じ難い、応力付加に強い構造の酸化物超電導線材を提供できる。   Since the peel strength between the base material and the second protective layer is smaller than the peel strength between the oxide superconducting layer and the intermediate layer, it is used for applications such as a superconducting coil or a superconducting cable. Even if it acts, delamination can be induced at the interface between the base material and the second protective layer, and delamination between the oxide superconducting layer and the adjacent layer can be suppressed. For this reason, when stress is applied, it is easy to induce delamination between the base material and the second protective layer, and it is difficult to cause delamination between the oxide superconducting layer and the intermediate layer. An oxide superconducting wire can be provided.

本発明において、前記第１の保護層上と前記第２の保護層上に前記安定化層が半田層を介し接合された構造を採用できる。
保護層上に半田層を介し安定化層を接合する構造の場合、半田層がＡｇまたはＡｇ合金の保護層の一部を溶食するが、第２の保護層の剥離強度を第１の保護層の剥離強度より低く好適な範囲に制御して基材裏面と第２の保護層との界面に剥離を誘起させ、故障に繋がらない構造の酸化物超電導線材を提供できる。
本発明において、前記基板裏面側の前記第２の保護層の厚さが１.５μｍ以下であることが好ましい。
第２の保護層の厚さが１．５μｍ以下であれば、第２の保護層と基材の間の剥離強度が酸化物超電導層と中間層の間の剥離強度よりも確実に弱くなる。このため、応力が作用した場合、基材と第２の保護層との間に層間剥離を誘導し易く、酸化物超電導層と中間層との間に層間剥離を生じ難い、酸化物超電導線材を提供できる。 In the present invention, it is possible to employ a structure in which the stabilization layer is bonded to the first protective layer and the second protective layer via a solder layer.
In the case of a structure in which the stabilization layer is joined to the protective layer via the solder layer, the solder layer erodes a part of the protective layer of Ag or Ag alloy, but the peel strength of the second protective layer is the first protection. It is possible to provide an oxide superconducting wire having a structure that does not lead to failure by inducing peeling at the interface between the back surface of the base material and the second protective layer by controlling to a suitable range lower than the peeling strength of the layer.
In the present invention, the thickness of the second protective layer on the back surface side of the substrate is preferably 1.5 μm or less.
If the thickness of the second protective layer is 1.5 μm or less, the peel strength between the second protective layer and the substrate is surely weaker than the peel strength between the oxide superconducting layer and the intermediate layer. For this reason, when stress acts, it is easy to induce delamination between the base material and the second protective layer, and hardly cause delamination between the oxide superconducting layer and the intermediate layer. Can be provided.

本発明に係る酸化物超電導線材の製造方法は、基材の主面上に中間層および酸化物超電導層を設けた酸化物超電導積層体に対し、前記酸化物超電導層上にＡｇまたはＡｇ合金からなる第１の保護層を形成した後、酸素アニ−ル処理を施し、その後、前記基材の裏面側にＡｇまたはＡｇ合金からなる第２の保護層を形成し、この第２の保護層形成後に酸素アニール処理を行うことなく安定化層を接合することを特徴とする。   The method for producing an oxide superconducting wire according to the present invention is based on an oxide superconducting laminate in which an intermediate layer and an oxide superconducting layer are provided on a main surface of a substrate, and Ag or Ag alloy is formed on the oxide superconducting layer. After forming the first protective layer, an oxygen annealing treatment is performed, and then a second protective layer made of Ag or an Ag alloy is formed on the back surface side of the substrate, and this second protective layer is formed. The stabilization layer is bonded without performing oxygen annealing treatment later.

第２の保護層を形成後に酸素アニール処理を施すことなく安定化層を接合するので、第２の保護層は基材裏面側に対し、剥離強度が弱い状態のまま安定化層で覆われる。第１の保護層を酸化物超電導層上に形成後に行う酸素アニール処理によって、酸化物超電導層には第１の保護層を介し必要な酸素が供給され、酸化物超電導導体の結晶の内部に必要な酸素が供給され、超電導特性が整えられる。第１の保護層は酸素アニール処理を受けるが第２の保護層は酸素アニール処理を受けないので、基材裏面に対する第２の保護層の剥離強度が他の層より低い状態のまま維持される。この結果、酸化物超電導線材に力が作用して酸化物超電導線材を構成する各層に剥離応力が作用した場合、基材裏面と第２の保護層との界面に剥離が誘起される結果、酸化物超電導層とその周囲の層との界面における層間剥離が抑制される。   Since the stabilization layer is bonded without performing the oxygen annealing treatment after the second protection layer is formed, the second protection layer is covered with the stabilization layer while the peel strength is weak with respect to the back surface side of the substrate. Oxygen annealing is performed after the first protective layer is formed on the oxide superconducting layer, so that the necessary oxygen is supplied to the oxide superconducting layer through the first protective layer and is necessary inside the crystal of the oxide superconducting conductor. Oxygen is supplied and superconducting properties are adjusted. Since the first protective layer is subjected to the oxygen annealing treatment, but the second protective layer is not subjected to the oxygen annealing treatment, the peel strength of the second protective layer with respect to the back surface of the base material is maintained lower than the other layers. . As a result, when a force acts on the oxide superconducting wire and a peeling stress acts on each layer constituting the oxide superconducting wire, peeling is induced at the interface between the back surface of the substrate and the second protective layer. Delamination at the interface between the superconducting layer and the surrounding layers is suppressed.

本発明の製造方法において、前記第２の保護層形成後に酸素アニール処理を施すことなく半田層を介し安定化層を接合することにより、前記酸化物超電導層と前記中間層の間の剥離強度よりも、前記基材と前記第２の保護層の間の剥離強度を低くすることが好ましい。
この結果、酸化物超電導線材に力が作用して酸化物超電導線材を構成する各層に剥離応力が作用した場合、基材裏面と第２の保護層との界面に剥離が誘起される結果、酸化物超電導層とその周囲の層との界面における層間剥離が抑制される。半田層を介し安定化層を接合する場合、半田層がＡｇまたはＡｇ合金の保護層の一部を溶食するが、第２の保護層の剥離強度を低くしておくことが有効なので、保護層の一部が溶食されたとして、基材裏面と第２の保護層との界面に剥離を誘起できる作用効果を奏する。 In the manufacturing method of the present invention, by bonding the stabilization layer via the solder layer without performing oxygen annealing after the formation of the second protective layer, the peel strength between the oxide superconducting layer and the intermediate layer can be determined. However, it is preferable to lower the peel strength between the substrate and the second protective layer.
As a result, when a force acts on the oxide superconducting wire and a peeling stress acts on each layer constituting the oxide superconducting wire, peeling is induced at the interface between the back surface of the substrate and the second protective layer. Delamination at the interface between the superconducting layer and the surrounding layers is suppressed. When the stabilization layer is joined via the solder layer, the solder layer erodes a part of the protective layer of Ag or Ag alloy, but it is effective to keep the peel strength of the second protective layer low. As a part of the layer is eroded, there is an effect that peeling can be induced at the interface between the back surface of the substrate and the second protective layer.

本発明の製造方法において、前記第２の保護層の厚さを１．５μｍ以下とすることができる。
第２の保護層の厚さが１．５μｍ以下であれば、第２の保護層と基材の間の剥離強度が酸化物超電導層と中間層の間の剥離強度よりも確実に弱くなる。また、半田層を介し安定化層を接合する場合、半田層がＡｇまたはＡｇ合金の保護層の一部を溶食するとしても、第２の保護層の剥離強度を好適な範囲に制御して基材裏面と第２の保護層との界面に剥離を誘起させ、故障に繋がらない構造の酸化物超電導線材を提供できる。 In the manufacturing method of the present invention, the thickness of the second protective layer can be 1.5 μm or less.
If the thickness of the second protective layer is 1.5 μm or less, the peel strength between the second protective layer and the substrate is surely weaker than the peel strength between the oxide superconducting layer and the intermediate layer. In addition, when the stabilization layer is bonded via the solder layer, the peel strength of the second protective layer is controlled within a suitable range even if the solder layer erodes part of the protective layer of Ag or Ag alloy. Peeling is induced at the interface between the back surface of the substrate and the second protective layer, and an oxide superconducting wire having a structure that does not lead to failure can be provided.

本発明に係る酸化物超電導線材ならば、超電導コイルあるいは超電導ケーブルなどの応用用途に利用し、外力により、あるいは、熱収縮率の違いにより作用する応力によって酸化物超電導線材に応力が作用した場合、該応力を基材と第２の保護層との界面における層間剥離誘導で解消できる。このため、酸化物超電導層とそれに隣接する層との間の層間剥離を抑制できる。従って、酸化物超電導線材に応力が作用しても、酸化物超電導層とそれに隣接する層との間で層間剥離を生じ難い、応力付加による超電導特性の劣化し難い酸化物超電導線材を提供できる。   If it is an oxide superconducting wire according to the present invention, it is used for an application such as a superconducting coil or a superconducting cable. The stress can be eliminated by delamination induction at the interface between the base material and the second protective layer. For this reason, delamination between the oxide superconducting layer and the adjacent layer can be suppressed. Therefore, even if a stress acts on the oxide superconducting wire, it is possible to provide an oxide superconducting wire which hardly causes delamination between the oxide superconducting layer and a layer adjacent to the oxide superconducting layer and hardly deteriorates the superconducting characteristics due to the stress.

本発明に係る酸化物超電導線材の一例を示す横断面斜視図。The cross-sectional perspective view which shows an example of the oxide superconducting wire which concerns on this invention. 実施例で得られた剥離強度と故障率の関係を示すグラフ。The graph which shows the relationship between the peeling strength and failure rate which were obtained in the Example. 比較例で得られた酸素アニール処理後の剥離強度と故障率の関係を示すグラフ。The graph which shows the relationship between the peeling strength after the oxygen annealing process obtained by the comparative example, and a failure rate. 実施例で得られた酸素アニール処理なしの場合の剥離強度と故障率の関係を示すグラフ。The graph which shows the relationship between the peeling strength at the time of not having oxygen annealing treatment obtained in the Example, and a failure rate. 従来の酸化物超電導線材の一例を示す横断面図。The cross-sectional view which shows an example of the conventional oxide superconducting wire. 従来の酸化物超電導線材の他の例を示す横断面図。The cross-sectional view which shows the other example of the conventional oxide superconducting wire.

以下、本発明に係る酸化物超電導線材の実施形態について図面に基づいて説明する。なお、以下の説明で用いる図面は、特徴をわかりやすくするために、便宜上特徴となる部分を拡大して示している場合があり、各構成要素の寸法比率などが実際と同じであるとは限らない。また、本発明は以下の実施形態に限定されるものではない。
図１に本発明に係る第１実施形態の酸化物超電導線材１を示す。
本実施形態の酸化物超電導線材１は、テープ状の基材１０の主面１０ａに中間層１１、酸化物超電導層１２が積層された酸化物超電導積層体１６と、その外周に積層された保護層２０と、保護層２０の外周の一部分を除いて覆った構成の安定化層１８とから構成されている。保護層２０は、Ａｇ又はＡｇ合金からなる第１の保護層１３と第２の保護層１４を有する。以下、図１を基に、酸化物超電導線材１の各構成要素について説明する。 Hereinafter, embodiments of an oxide superconducting wire according to the present invention will be described with reference to the drawings. In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent. The present invention is not limited to the following embodiment.
FIG. 1 shows an oxide superconducting wire 1 according to a first embodiment of the present invention.
The oxide superconducting wire 1 of the present embodiment includes an oxide superconducting laminate 16 in which an intermediate layer 11 and an oxide superconducting layer 12 are laminated on a main surface 10a of a tape-like substrate 10, and a protection laminated on the outer periphery thereof. The layer 20 and the stabilization layer 18 configured to cover a part of the outer periphery of the protective layer 20 except for a part thereof. The protective layer 20 includes a first protective layer 13 and a second protective layer 14 made of Ag or an Ag alloy. Hereinafter, each component of the oxide superconducting wire 1 will be described with reference to FIG.

基材１０は、ハステロイ（米国ヘインズ社製商品名）に代表されるニッケル合金やステンレス鋼、ニッケル合金に集合組織を導入した配向Ｎｉ−Ｗ合金等が適用される。基材１０の厚さは、目的に応じて適宜調整すれば良く、１０〜５００μｍの範囲とすることができる。
基材１０の主面１０ａ上に形成される中間層１１は、一例として、基材側から順に拡散防止層とベッド層と配向層とキャップ層の積層構造とすることができるが、拡散防止層とベッド層の一方あるいは両方を略して構成しても良い。
拡散防止層は、Ｓｉ３Ｎ４、Ａｌ２Ｏ３、ＧＺＯ（Ｇｄ２Ｚｒ２Ｏ７）等から構成され、例えば厚さ１０〜４００ｎｍに形成される。ベッド層は、界面反応性を低減し、その上に形成される膜の配向性を得るため層であり、Ｙ２Ｏ３、Ｅｒ２Ｏ３、ＣｅＯ２、Ｄｙ２Ｏ３、Ｅｒ２Ｏ３、Ｅｕ２Ｏ３、Ｈｏ２Ｏ３、Ｌａ２Ｏ３等からなり、その厚さは例えば１０〜１００ｎｍである。配向層は、その上のキャップ層の結晶配向性を制御するために２軸配向する物質から形成される。配向層の材質としては、Ｇｄ２Ｚｒ２Ｏ７、ＭｇＯ、ＺｒＯ２−Ｙ２Ｏ３（ＹＳＺ）、ＳｒＴｉＯ３、ＣｅＯ２、Ｙ２Ｏ３、Ａｌ２Ｏ３、Ｇｄ２Ｏ３、Ｚｒ２Ｏ３、Ｈｏ２Ｏ３、Ｎｄ２Ｏ３等の金属酸化物を例示することができる。
配向層はＩＢＡＤ（Ion-Beam-Assisted Deposition）法で形成することが好ましい。キャップ層は、上述の配向層の表面に成膜されて結晶粒が面内方向に自己配向し得る材料からなり、具体的には、ＣｅＯ２、Ｙ２Ｏ３、Ａｌ２Ｏ３、Ｇｄ２Ｏ３、ＺｒＯ２、ＹＳＺ、Ｈｏ２Ｏ３、Ｎｄ２Ｏ３、ＬａＭｎＯ３等からなる。キャップ層の膜厚は５０〜５０００ｎｍの範囲に形成できる。 As the base material 10, a nickel alloy represented by Hastelloy (trade name, manufactured by Haynes, USA), an oriented Ni—W alloy in which a texture is introduced into a nickel alloy, or the like is applied. What is necessary is just to adjust the thickness of the base material 10 suitably according to the objective, and it can be set as the range of 10-500 micrometers.
As an example, the intermediate layer 11 formed on the main surface 10a of the base material 10 can have a laminated structure of a diffusion prevention layer, a bed layer, an alignment layer, and a cap layer in order from the base material side. One or both of the bed layers may be omitted.
The diffusion prevention layer is made of Si 3 N 4 , Al 2 O 3 , GZO (Gd 2 Zr 2 O 7 ), etc., and is formed to a thickness of 10 to 400 nm, for example. The bed layer is a layer for reducing the interfacial reactivity and obtaining the orientation of the film formed thereon. Y 2 O 3 , Er 2 O 3 , CeO 2 , Dy 2 O 3, Er 2 O 3 , Eu 2 O 3 , Ho 2 O 3 , La 2 O 3, etc., and the thickness is, for example, 10 to 100 nm. The orientation layer is formed from a biaxially oriented material in order to control the crystal orientation of the cap layer thereon. As the material of the alignment layer, Gd 2 Zr 2 O 7 , MgO, ZrO 2 —Y 2 O 3 (YSZ), SrTiO 3 , CeO 2 , Y 2 O 3 , Al 2 O 3 , Gd 2 O 3 , Zr 2 Examples thereof include metal oxides such as O 3 , Ho 2 O 3 , and Nd 2 O 3 .
The alignment layer is preferably formed by an IBAD (Ion-Beam-Assisted Deposition) method. The cap layer is formed on the surface of the above-described alignment layer and is made of a material that allows crystal grains to self-orient in the in-plane direction. Specifically, CeO 2 , Y 2 O 3 , Al 2 O 3 , Gd 2 O 3, ZrO 2, YSZ, Ho 2 O 3, Nd 2 O 3, consist of LaMnO 3 like. The film thickness of the cap layer can be formed in the range of 50 to 5000 nm.

酸化物超電導層１２は酸化物超電導体として公知のもので良く、具体的には、ＲＥ−１２３系と呼ばれるＲＥＢａ２Ｃｕ３Ｏｙ（ＲＥは希土類元素であるＳｃ、Ｙ、Ｌａ、Ｃｅ、Ｐｒ、Ｎｄ、Ｐｍ、Ｓｍ、Ｅｕ、Ｇｄ、Ｔｂ、Ｄｙ、Ｈｏ、Ｅｒ、Ｔｍ、Ｙｂ、Ｌｕのうちの１種又は２種以上を表す）を例示できる。この酸化物超電導層１２として、Ｙ１２３（ＹＢａ２Ｃｕ３Ｏ７−Ｘ）又はＧｄ１２３（ＧｄＢａ２Ｃｕ３Ｏ７−Ｘ）などを例示できる。酸化物超電導層１２の厚みは、０．５〜５μｍ程度であって、均一な厚みであることが好ましい。 The oxide superconducting layer 12 may be a known oxide superconductor. Specifically, REBa 2 Cu 3 O y (RE is a rare earth element such as Sc, Y, La, Ce, Pr). , Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. Examples of the oxide superconducting layer 12 include Y123 (YBa 2 Cu 3 O 7-X ) or Gd123 (GdBa 2 Cu 3 O 7-X ). The oxide superconducting layer 12 has a thickness of about 0.5 to 5 μm and preferably a uniform thickness.

上述の基材１０、中間層１１、酸化物超電導層１２によって、酸化物超電導積層体１６が構成されている。図１に示すように、この酸化物超電導積層体１６は、保護層２０によって外周を覆われており、酸化物超電導層１２の主面上に第１の保護層１３の主面部１３ｂが形成され、基材１０の裏面１０ｂに第２の保護層１４の主面部１４ｂが形成され、前記酸化物超電導積層体１６の側面１６ａに第１の保護層１３及び第２の保護層１４の側面部１３ａ、１４ａが形成されて、酸化物超電導導体１５が構成されている。   An oxide superconducting laminate 16 is constituted by the base material 10, the intermediate layer 11, and the oxide superconducting layer 12 described above. As shown in FIG. 1, the outer periphery of the oxide superconducting laminate 16 is covered with a protective layer 20, and the main surface portion 13 b of the first protective layer 13 is formed on the main surface of the oxide superconducting layer 12. The main surface portion 14b of the second protective layer 14 is formed on the back surface 10b of the base material 10, and the first protective layer 13 and the side surface portion 13a of the second protective layer 14 are formed on the side surface 16a of the oxide superconducting laminate 16. , 14a are formed to form the oxide superconducting conductor 15.

第１の保護層１３は、酸化物超電導層１２の主面１２ａ上に主に形成されるＡｇ又はＡｇ合金からなる層であり、スパッタ法などの成膜法により形成される。第１の保護層１３は、主面１２ａのみならず、酸化物超電導積層体１６の側面１６ａ、１６ａ及び裏面１６ｂに形成されていてもよい。特に、スパッタ法により第１の保護層１３を形成する場合、スパッタ粒子（Ａｇ粒子）の一部が酸化物超電導積層体１６の側面１６ａにも回り込むため、側面部１３ａが形成される。なお、酸化物超電導積層体１６の裏面側にも一部Ａｇの回り込みが発生するが、図１においては、裏面側に形成される保護層は省略している。
第１の保護層１３は、酸化物超電導層１２を保護する役割を果たしている。また、通電の際の事故時に発生する過電流をバイパスする機能も有する。加えて、酸化物超電導層１２とこの層よりも上面に設ける層との間で起こる化学反応を抑制し、一方の層の元素の一部が他方の層側に侵入して組成がくずれることによる超電導特性の低下を防ぐなどの機能を有する。 The first protective layer 13 is a layer made of Ag or an Ag alloy mainly formed on the main surface 12a of the oxide superconducting layer 12, and is formed by a film forming method such as a sputtering method. The first protective layer 13 may be formed not only on the main surface 12 a but also on the side surfaces 16 a and 16 a and the back surface 16 b of the oxide superconducting laminate 16. In particular, when the first protective layer 13 is formed by sputtering, a part of the sputtered particles (Ag particles) also wraps around the side surface 16a of the oxide superconducting laminate 16, so that the side surface portion 13a is formed. In addition, although part of Ag wraps around the back side of the oxide superconducting laminate 16, the protective layer formed on the back side is omitted in FIG.
The first protective layer 13 serves to protect the oxide superconducting layer 12. It also has a function of bypassing overcurrent that occurs in the event of an energization accident. In addition, the chemical reaction occurring between the oxide superconducting layer 12 and a layer provided on the upper surface of this layer is suppressed, and a part of the elements of one layer penetrates into the other layer and the composition is broken. It has functions such as preventing deterioration of superconducting properties.

第１の保護層１３の成膜後に、酸素雰囲気下において３００〜５００℃、１〜２０ｈの熱処理を行う（酸素アニール処理）。酸化物超電導層１２は、成膜後には酸素が不足した結晶構造となっているため、上記の酸素アニール処理を行うことによって、酸化物超電導層１２に必要な酸素を供給して結晶構造を整えることができる。
第２の保護層１４は、基材１０の裏面１０ｂ上に形成される主面部１４ｂと、前記酸化物超電導積層体１６の側面１６ａ側に形成される側面部１４ａからなる。
第２の保護層１４は、前記第１の保護層１３と共に、事故時の過電流をバイパスする機能を有する。第２の保護層１４は、Ａｇ又はＡｇ合金からなり、第１の保護層１３を形成する場合と同様にスパッタ法などの成膜法により形成される。
第２の保護層１４を成膜後、上述の酸素アニール処理を行ない、安定化層１８の接合を行うことができる。 After the first protective layer 13 is formed, heat treatment is performed at 300 to 500 ° C. for 1 to 20 hours in an oxygen atmosphere (oxygen annealing treatment). Since the oxide superconducting layer 12 has a crystal structure in which oxygen is insufficient after film formation, the oxygen annealing process is performed to supply the necessary oxygen to the oxide superconducting layer 12 so as to adjust the crystal structure. be able to.
The second protective layer 14 includes a main surface portion 14 b formed on the back surface 10 b of the substrate 10 and a side surface portion 14 a formed on the side surface 16 a side of the oxide superconducting laminate 16.
The second protective layer 14 has a function of bypassing overcurrent at the time of an accident together with the first protective layer 13. The second protective layer 14 is made of Ag or an Ag alloy, and is formed by a film forming method such as a sputtering method in the same manner as the first protective layer 13 is formed.
After the second protective layer 14 is formed, the oxygen annealing treatment described above can be performed to join the stabilization layer 18.

安定化層１８は、一面側にはんだ層を有する金属テープで保護層２０を覆って形成される。金属テープで安定化層１８を形成するには、保護層２０を備えた酸化物超電導積層体１６の周囲を囲むように金属テープを横断面Ｃ字型になるように折り曲げ加工しつつ加熱ロールなどの成形装置を用いて半田層を溶融させ、金属テープで保護層２０の周囲を囲んだまま常温に冷却して半田層を固化し、図１に示すように半田層１９を介し一体化した構造とすることが好ましい。
なお、図１に示す構造では横断面Ｃ字型に金属テープを成形したので、第２の保護層１４の外面側に安定化層１８で覆われていない領域１４ｃが形成されているが、金属テープの幅を調整してこの領域１４ｃも全て安定化層１８で覆った構造としても良い。 The stabilization layer 18 is formed by covering the protective layer 20 with a metal tape having a solder layer on one side. In order to form the stabilization layer 18 with a metal tape, a heating roll or the like is performed while bending the metal tape so as to have a C-shaped cross section so as to surround the periphery of the oxide superconducting laminate 16 provided with the protective layer 20. The solder layer is melted by using the molding apparatus, and the solder layer is solidified by being cooled to room temperature while surrounding the protective layer 20 with a metal tape, and integrated through the solder layer 19 as shown in FIG. It is preferable that
In the structure shown in FIG. 1, since the metal tape is formed in a C-shaped cross section, a region 14c that is not covered with the stabilization layer 18 is formed on the outer surface side of the second protective layer 14. A structure in which the width of the tape is adjusted so that the region 14c is entirely covered with the stabilizing layer 18 may be employed.

半田層１９に用いる半田は、特に限定されるものではなく従来公知の半田を使用可能である。例えば、Ｓｎ、Ｓｎ−Ａｇ系合金、Ｓｎ−Ｂｉ系合金、Ｓｎ−Ｃｕ系合金、Ｓｎ−Ｚｎ系合金などのＳｎを主成分とする合金よりなる鉛フリー半田、Ｐｂ−Ｓｎ系合金半田、共晶半田、低温半田などが挙げられ、これらの半田を一種又は二種以上組み合わせて使用することができる。これらの中でも、融点が３００℃以下の半田を用いることが好ましい。これにより、３００℃以下の温度で安定化層１８と第１の保護層１３又は第２の保護層１４を半田付けすることが可能となるので、半田付けの熱によって酸化物超電導層１２の特性が劣化することを抑止できる。   The solder used for the solder layer 19 is not particularly limited, and a conventionally known solder can be used. For example, lead-free solder, Pb-Sn alloy alloy, Sn, Sn—Ag alloy, Sn—Bi alloy, Sn—Cu alloy, Sn—Zn alloy, etc. Crystal solder, low-temperature solder, and the like can be mentioned, and these solders can be used singly or in combination of two or more. Among these, it is preferable to use solder having a melting point of 300 ° C. or less. As a result, the stabilization layer 18 and the first protective layer 13 or the second protective layer 14 can be soldered at a temperature of 300 ° C. or lower. Therefore, the characteristics of the oxide superconducting layer 12 can be increased by the heat of soldering. Can be prevented from deteriorating.

図１に示す構造の酸化物超電導線材１を製造する場合、第１の保護層１３を成膜後に酸素アニール処理を行い、その後に第２の保護層１４を成膜し、酸素アニール処理を施してから半田層１９を用いて安定化層１８を接合することができる。また、第１の保護層１３を成膜後に第２の保護層１４を成膜し、酸素アニール処理を施してから半田層１９を用いて安定化層１８を接合することができる。さらに、第１の保護層１３を成膜後に酸素アニール処理を行い、その後に第２の保護層１４を成膜し、酸素アニール処理を施すことなく半田層１９を用いて安定化層１８を接合することもできる。なお、第２の保護層１４を成膜後に酸素アニールを行う場合、酸素アニールに替えて酸素を用いない真空雰囲気や不活性ガス中での熱処理を行うと酸化物超電導層１２から酸素が抜けて臨界電流値が低下するおそれがある。このため、第２の保護層１４の形成後に加熱処理を行う場合は、酸素アニール処理を行うことが好ましい。
スパッタなどの成膜法により形成したＡｇまたはＡｇ合金の層は、酸素アニール処理時の加熱温度に曝されると、再結晶化が起こるとともに、ハステロイからなる基材１０に対する接合強度が向上する。しかし、安定化層を形成する際に、ＡｇまたはＡｇ合金の層と半田層１９の接する界面では、半田層１９に含まれているＳｎの影響でＡｇの溶食が生じ、ＡｇまたはＡｇ合金の層が基材１０の裏面側に密着する場合の剥離強度は低下するため、基材１０に対する第２の保護層１４の剥離強度を酸化物超電導層１２の剥離強度よりも低くすることができる。 When the oxide superconducting wire 1 having the structure shown in FIG. 1 is manufactured, an oxygen annealing process is performed after the first protective layer 13 is formed, and then a second protective layer 14 is formed and an oxygen annealing process is performed. Then, the stabilization layer 18 can be joined using the solder layer 19. Further, after the first protective layer 13 is formed, the second protective layer 14 is formed, and after the oxygen annealing treatment is performed, the stabilization layer 18 can be bonded using the solder layer 19. Further, after the first protective layer 13 is formed, an oxygen annealing process is performed, after which a second protective layer 14 is formed, and the stabilization layer 18 is bonded using the solder layer 19 without performing the oxygen annealing process. You can also Note that, when oxygen annealing is performed after the second protective layer 14 is formed, oxygen is released from the oxide superconducting layer 12 when heat treatment is performed in a vacuum atmosphere or inert gas that does not use oxygen instead of oxygen annealing. The critical current value may decrease. For this reason, when heat treatment is performed after the second protective layer 14 is formed, it is preferable to perform oxygen annealing.
When an Ag or Ag alloy layer formed by a film forming method such as sputtering is exposed to the heating temperature during the oxygen annealing treatment, recrystallization occurs and the bonding strength to the base material 10 made of hastelloy is improved. However, when forming the stabilization layer, Ag corrosion occurs due to the influence of Sn contained in the solder layer 19 at the interface where the Ag or Ag alloy layer and the solder layer 19 are in contact with each other. Since the peel strength when the layer adheres to the back surface side of the substrate 10 is lowered, the peel strength of the second protective layer 14 with respect to the substrate 10 can be made lower than the peel strength of the oxide superconducting layer 12.

このような構造を採用することで、酸化物超電導線材１に対し力が作用して積層構造の部分を剥離しようとする応力が作用した場合、基材１０の裏面と第２の保護層１４との界面に積極的に剥離を誘導することができ、酸化物超電導層１２とその周囲の層との界面部分に剥離を生じさせることのない構造を実現できる。
また、この効果は第２の保護層１４の膜厚の調整によってより有効に作用させることができる。
第２の保護層１４の膜厚（基材１０の裏面側に形成された部分の膜厚）を１．５μｍ以下とすることにより、有効な溶食が生じるため、酸化物超電導層１２とその周囲の層との剥離強度よりも、第２の保護層１４の剥離強度を確実に低くすることができる。これにより、酸化物超電導線材１に応力が作用しても、第２の保護層１４に層間剥離を誘導できる構造を確実に得ることができる。
上述の構造を得る場合、第２の保護層１４を形成後、酸素アニール処理を行わないことが好ましい。酸素アニール処理を行わないことにより、基材１０と第２の保護層１４との接合強度が低くなるため、第２の保護層１４の剥離強度はいっそう低くなり、酸化物超電導層１２の剥離をより効果的に防止できる。 By adopting such a structure, when a force acts on the oxide superconducting wire 1 and a stress is applied to peel off the portion of the laminated structure, the back surface of the substrate 10 and the second protective layer 14 Peeling can be positively induced at the interface of the oxide, and a structure that does not cause peeling at the interface portion between the oxide superconducting layer 12 and the surrounding layers can be realized.
In addition, this effect can be more effectively caused by adjusting the film thickness of the second protective layer 14.
Since effective corrosion occurs when the film thickness of the second protective layer 14 (the film thickness of the portion formed on the back side of the substrate 10) is 1.5 μm or less, the oxide superconducting layer 12 and its The peel strength of the second protective layer 14 can be reliably lowered than the peel strength with the surrounding layers. Thereby, even if stress acts on the oxide superconducting wire 1, a structure that can induce delamination in the second protective layer 14 can be reliably obtained.
In the case of obtaining the above-described structure, it is preferable not to perform the oxygen annealing treatment after forming the second protective layer 14. By not performing the oxygen annealing treatment, the bonding strength between the base material 10 and the second protective layer 14 is lowered, so that the peeling strength of the second protective layer 14 is further lowered, and the oxide superconducting layer 12 is peeled off. It can be prevented more effectively.

以下、実施例を示して本発明をさらに詳細に説明するが、本発明はこれらの実施例に限定されるものではない。
「試験例１」
（試料の作製）
ハステロイＣ−２７６（米国ヘインズ社商品名）からなる幅５ｍｍ、厚さ０．１ｍｍ、長さ１０００ｍｍのテープ状の基材の表面を平均粒径３μｍのアルミナ粒子を用いて研磨し、表面を平滑化した。次に、前記基材の表面をアセトンにより脱脂、洗浄した。
この基材の主面上にイオンビームスパッタ法によりＡｌ２Ｏ３層（拡散防止層；膜厚１００ｎｍ）を成膜し、その上に、イオンビームスパッタ法によりＹ２Ｏ３層（ベッド層；膜厚３０ｎｍ）を成膜した。
次いで、このベッド層上に、イオンビームアシスト蒸着法（ＩＢＡＤ法）によりＭｇＯ層（金属酸化物層；膜厚５〜１０ｎｍ）を形成し、その上にパルスレーザー蒸着法（ＰＬＤ法）により５００ｎｍ厚のＣｅＯ２層（キャップ層）を成膜した。次いでＣｅＯ２層上にＰＬＤ法により２．０μｍ厚のＧｄＢａ２Ｃｕ３Ｏ７−δ層（酸化物超電導層）を形成した。
さらに酸化物超電導層側からスパッタ法により酸化物超電導層上に６μｍ厚のＡｇからなる第１の保護層を形成し、５００℃で１０時間、酸素雰囲気中において酸素アニールし、２６時間の炉冷却後に取り出した。 EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited to these Examples.
“Test Example 1”
(Sample preparation)
The surface of a tape-shaped substrate made of Hastelloy C-276 (trade name of US Haynes Co., Ltd.) having a width of 5 mm, a thickness of 0.1 mm, and a length of 1000 mm is polished with alumina particles having an average particle diameter of 3 μm to smooth the surface. Turned into. Next, the surface of the substrate was degreased and washed with acetone.
An Al 2 O 3 layer (diffusion prevention layer; film thickness 100 nm) is formed on the main surface of the substrate by ion beam sputtering, and a Y 2 O 3 layer (bed layer; A film thickness of 30 nm) was formed.
Next, an MgO layer (metal oxide layer; film thickness of 5 to 10 nm) is formed on the bed layer by an ion beam assisted deposition method (IBAD method), and a thickness of 500 nm is formed thereon by a pulse laser deposition method (PLD method). A CeO 2 layer (cap layer) was formed. Next, a 2.0 μm thick GdBa 2 Cu 3 O 7-δ layer (oxide superconducting layer) was formed on the CeO 2 layer by the PLD method.
Further, a first protective layer made of Ag having a thickness of 6 μm is formed on the oxide superconducting layer by sputtering from the oxide superconducting layer side, oxygen-annealed in an oxygen atmosphere at 500 ° C. for 10 hours, and furnace cooling for 26 hours It was taken out later.

次に、基材の裏面側からスパッタ法により基材上に１μｍ厚のＡｇからなる第２の保護層を形成し、酸化物超電導導体を得た。第２の保護層を形成する際、膜厚を１．５μｍ、２．０μｍ、２．５μｍ、３．０μｍにそれぞれ変更して複数の酸化物超電導導体を作製し、第２の保護層の膜厚が異なる合計５種類の酸化物超電導導体試料を複数作製した。
これらの酸化物超電導導体に５００℃で１０時間、酸素雰囲気中において酸素アニールし、２６時間の炉冷却後に酸素アニール炉から取り出した。
次いで各酸化物超電導導体に厚さ２０μｍ、幅１０ｍｍであり、片面に厚さ２〜４μｍのＳｎめっき層を有する無酸素銅箔を用い、加熱加圧ロールを用いてＣ字型に折り曲げ成形しながら酸化物超電導導体の周囲を囲んで安定化層を形成し、試験用の５種類の酸化物超電導線材を得た。 Next, a second protective layer made of Ag having a thickness of 1 μm was formed on the base material by sputtering from the back side of the base material to obtain an oxide superconductor. When forming the second protective layer, the thickness of the film is changed to 1.5 μm, 2.0 μm, 2.5 μm, and 3.0 μm to produce a plurality of oxide superconducting conductors. A total of five types of oxide superconducting conductor samples having different thicknesses were produced.
These oxide superconducting conductors were subjected to oxygen annealing in an oxygen atmosphere at 500 ° C. for 10 hours, and were taken out from the oxygen annealing furnace after cooling for 26 hours in the furnace.
Next, each oxide superconducting conductor is 20 μm thick and 10 mm wide, and an oxygen-free copper foil having a Sn plating layer of 2 to 4 μm thick on one side is bent into a C shape using a heating and pressing roll. However, a stabilization layer was formed surrounding the periphery of the oxide superconducting conductor to obtain five types of oxide superconducting wires for testing.

得られた各酸化物超電導線材において基材裏面側に被覆された安定化層に対し、外径２．７ｍｍの円柱状のピンを安定化層上にエポキシ系の接着剤で接着後、酸化物超電導層の外側に被着されている安定化層の外面をバッキングプレートにエポキシ系の接着剤で接着し、前記ピンに対し軸方向（酸化物超電導線材の安定化層に対し９０゜方向）に引張力を加えて剥離力を測定するスタッドプル法により剥離力を測定した。
スタッドプル法による剥離力の測定結果を図２に示す。図２の剥離強度に対する累積故障率のワイブルプロットを示す。
図２に示す通り、Ａｇの保護層の膜厚が減少することに相関し、剥離強度が低下することがわかる。酸化物超電導層の剥離強度は３０ＭＰａ以上であり、剥離強度３０ＭＰａのラインを境界として見ると、膜厚１．５μｍ以下の保護層では９０％以上の試料について、剥離強度が３０ＭＰａ未満であった。これらの試料はすべて基材表面のＡｇが剥離していた。 In each of the obtained oxide superconducting wires, a cylindrical pin having an outer diameter of 2.7 mm is bonded onto the stabilization layer with an epoxy adhesive to the stabilization layer coated on the back side of the substrate, and then the oxide. The outer surface of the stabilization layer deposited on the outside of the superconducting layer is bonded to the backing plate with an epoxy adhesive, and is axially directed to the pin (90 ° direction with respect to the stabilizing layer of the oxide superconducting wire). The peeling force was measured by a stud pull method in which a tensile force was applied to measure the peeling force.
The measurement result of the peeling force by the stud pull method is shown in FIG. 3 shows a Weibull plot of cumulative failure rate against peel strength in FIG.
As shown in FIG. 2, it can be seen that the peel strength decreases in correlation with the decrease in the thickness of the protective layer of Ag. The peel strength of the oxide superconducting layer is 30 MPa or more, and when the line having a peel strength of 30 MPa is taken as a boundary, the peel strength is less than 30 MPa for 90% or more of the samples in the protective layer having a thickness of 1.5 μm or less. In all these samples, Ag on the substrate surface was peeled off.

この種の酸化物超電導線材の剥離強度として、キャップ層と酸化物超電導層の界面が一番弱い部分と認識することができるので、図２の結果において剥離強度３０ＭＰａを下回る、剥離強度を示すには、Ａｇの保護層の厚さを１μｍ、あるいは１．５μｍとするならば、故障率９０％で換算して保護層として好ましい厚さであると判断できる。
即ち、上述の条件で酸化物超電導線材を製造した場合、Ａｇの保護層の厚さを１．５μｍ以下とするならば、キャップ層と酸化物超電導層の界面が剥離せずに、Ａｇの保護層と基材裏面との界面で剥離を生じる構造を実現できる。 As the peel strength of this kind of oxide superconducting wire, it can be recognized that the interface between the cap layer and the oxide superconducting layer is the weakest part, so the peel strength is less than 30 MPa in the result of FIG. If the thickness of the protective layer of Ag is 1 μm or 1.5 μm, it can be determined that the thickness is preferable as the protective layer in terms of a failure rate of 90%.
That is, when an oxide superconducting wire is manufactured under the above-described conditions, if the thickness of the Ag protective layer is 1.5 μm or less, the interface between the cap layer and the oxide superconducting layer does not peel off and the Ag protective layer is protected. A structure in which peeling occurs at the interface between the layer and the back surface of the substrate can be realized.

「試験例２」
先の試験例１で行った条件と同等の条件で酸化物超電導導体を作製する際、酸素アニール処理後に基材裏面側に厚さ１μｍのＡｇの第２の保護層を形成し、更に酸素アニール処理を施した試料と酸素アニール処理を施さない試料を作製し、上述の条件と同等条件でスタッドプル法に基づき剥離強度の試験を行った。
それらの結果を図３と図４に示す。
図３に示す結果は、第２の保護層を形成後、酸素アニール処理を行った試料の剥離強度を示し、図４に示す結果は、第２の保護層を形成後、酸素アニール処理を行っていない試料の剥離強度を示す。 "Test Example 2"
When an oxide superconducting conductor is produced under the same conditions as those in Test Example 1 above, a second protective layer of 1 μm thick Ag is formed on the back side of the substrate after the oxygen annealing treatment, and oxygen annealing is further performed. A sample subjected to the treatment and a sample not subjected to the oxygen annealing treatment were prepared, and a peel strength test was performed based on the stud pull method under the same conditions as described above.
The results are shown in FIGS.
The result shown in FIG. 3 shows the peel strength of the sample subjected to the oxygen annealing treatment after forming the second protective layer, and the result shown in FIG. 4 shows the result of the oxygen annealing treatment after forming the second protective layer. It shows the peel strength of the sample that is not.

図３に示す酸素アニール処理を施した酸化物超電導線材試料の剥離強度試験では、全サンプルにおいて第２の保護層と基材の界面で剥離が起きるよりも先にピンを接着している接着剤の樹脂部分で樹脂破壊を生じた。
図４に示す酸素アニール処理を施していない酸化物超電導線材試料の剥離強度試験では、全てＡｇの第２の保護層と基材裏面との界面で剥離が生じた。
図３と図４の対比から、酸素アニール処理しない方が剥離強度が低下しているので、酸素アニール処理を行わないことにより、基材裏面と第２の保護層との界面に剥離を誘起できる構造を提供できることがわかった。 In the peel strength test of the oxide superconducting wire sample subjected to the oxygen annealing treatment shown in FIG. 3, an adhesive that bonds the pin before the peeling occurs at the interface between the second protective layer and the base material in all samples. Resin breakage occurred in the resin part.
In the peel strength test of the oxide superconducting wire sample not subjected to the oxygen annealing treatment shown in FIG. 4, peeling occurred at the interface between the second protective layer of Ag and the back surface of the substrate.
From the comparison between FIG. 3 and FIG. 4, the peel strength is lower when the oxygen annealing treatment is not performed. Therefore, the peeling can be induced at the interface between the back surface of the substrate and the second protective layer by not performing the oxygen annealing treatment. It has been found that a structure can be provided.

１…酸化物超電導線材、１０…基材、１０ａ…主面、１０ｂ…裏面、１１…中間層、１２…酸化物超電導層、１３…第１の保護層、１３ａ、１４ａ…側面部、１３ｂ、１４ｂ…主面部、１４…第２の保護層、１５…酸化物超電導導体、１６…酸化物超電導積層体、１６ａ…側面、１８…安定化層、１９…半田層、２０…保護層。   DESCRIPTION OF SYMBOLS 1 ... Oxide superconducting wire, 10 ... Base material, 10a ... Main surface, 10b ... Back surface, 11 ... Intermediate layer, 12 ... Oxide superconducting layer, 13 ... 1st protective layer, 13a, 14a ... Side surface part, 13b, 14b ... Main surface portion, 14 ... Second protective layer, 15 ... Oxide superconducting conductor, 16 ... Oxide superconducting laminate, 16a ... Side, 18 ... Stabilizing layer, 19 ... Solder layer, 20 ... Protective layer.

Claims (5)

基材の主面上に中間層および酸化物超電導層が形成された酸化物超電導積層体と、前記酸化物超電導積層体の外周に形成された保護層と、前記保護層上に形成された安定化層とを備え、
前記保護層が、少なくとも前記酸化物超電導層の主面を覆うように形成されたＡｇまたはＡｇ合金からなる第１の保護層と、前記基材の主面とは反対側の裏面を少なくとも覆うように形成されたＡｇまたはＡｇ合金からなる第２の保護層を含み、
前記安定化層が、前記第１の保護層と前記第２の保護層の少なくとも一部を覆って設けられ、
前記酸化物超電導層と前記中間層の間の剥離強度より、前記基材と前記第２の保護層の間の剥離強度が小さくされた酸化物超電導線材。 An oxide superconducting laminate in which an intermediate layer and an oxide superconducting layer are formed on the main surface of the substrate, a protective layer formed on the outer periphery of the oxide superconducting laminate, and a stable layer formed on the protective layer And comprising
The protective layer covers at least a first protective layer made of Ag or an Ag alloy formed so as to cover at least a main surface of the oxide superconducting layer, and at least a back surface opposite to the main surface of the base material. A second protective layer made of Ag or an Ag alloy formed on
The stabilization layer is provided to cover at least a part of the first protective layer and the second protective layer;
An oxide superconducting wire in which the peel strength between the substrate and the second protective layer is smaller than the peel strength between the oxide superconducting layer and the intermediate layer. 前記第１の保護層上と前記第２の保護層上に前記安定化層が半田層を介し接合された請求項１に記載の酸化物超電導線材。   2. The oxide superconducting wire according to claim 1, wherein the stabilization layer is bonded to the first protective layer and the second protective layer via a solder layer. 前記基材裏面側の前記第２の保護層の厚さが１.５μｍ以下である請求項１または請求項２に記載の酸化物超電導線材。 The oxide superconducting wire according to claim 1 or 2, wherein the thickness of the second protective layer on the back surface side of the substrate is 1.5 µm or less. 基材の主面上に中間層および酸化物超電導層を設けた酸化物超電導積層体に対し、前記酸化物超電導層上にＡｇまたはＡｇ合金からなる第１の保護層を形成した後、酸素アニ−ル処理を施し、その後、前記基材の裏面側にＡｇまたはＡｇ合金からなる第２の保護層を形成し、この第２の保護層形成後に酸素アニール処理を施すことなく安定化層を接合し、前記酸化物超電導層と前記中間層の間の剥離強度よりも、前記基材と前記第２の保護層の間の剥離強度を低くする酸化物超電導線材の製造方法。 For the oxide superconducting laminate in which the intermediate layer and the oxide superconducting layer are provided on the main surface of the base material, a first protective layer made of Ag or an Ag alloy is formed on the oxide superconducting layer. -After that, a second protective layer made of Ag or an Ag alloy is formed on the back side of the base material, and the stabilization layer is bonded without performing oxygen annealing after the formation of the second protective layer. And the manufacturing method of the oxide superconducting wire which makes the peeling strength between the said base material and the said 2nd protective layer lower than the peeling strength between the said oxide superconducting layer and the said intermediate | middle layer . 前記第２の保護層の厚さを１．５μｍ以下とする請求項４に記載の酸化物超電導線材の製造方法。 The method for producing an oxide superconducting wire according to claim 4 , wherein the thickness of the second protective layer is 1.5 μm or less.
JP2014075439A 2014-04-01 2014-04-01 Oxide superconducting wire and manufacturing method thereof Active JP6012658B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2014075439A JP6012658B2 (en) 2014-04-01 2014-04-01 Oxide superconducting wire and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2014075439A JP6012658B2 (en) 2014-04-01 2014-04-01 Oxide superconducting wire and manufacturing method thereof

Publications (2)

Publication Number Publication Date
JP2015198009A JP2015198009A (en) 2015-11-09
JP6012658B2 true JP6012658B2 (en) 2016-10-25

Family

ID=54547584

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2014075439A Active JP6012658B2 (en) 2014-04-01 2014-04-01 Oxide superconducting wire and manufacturing method thereof

Country Status (1)

Country Link
JP (1) JP6012658B2 (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018150469A1 (en) * 2017-02-14 2018-08-23 住友電気工業株式会社 Superconducting wire material and superconducting coil
WO2018150457A1 (en) * 2017-02-14 2018-08-23 住友電気工業株式会社 Superconducting wire material and superconducting coil
WO2018150470A1 (en) * 2017-02-14 2018-08-23 住友電気工業株式会社 Superconducting wire material and superconducting coil
CN110268484B (en) * 2017-02-14 2021-05-07 住友电气工业株式会社 Superconducting wire and superconducting coil
JP6751054B2 (en) * 2017-06-07 2020-09-02 株式会社フジクラ Oxide superconducting wire, superconducting coil, and method for manufacturing oxide superconducting wire

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5084766B2 (en) * 2009-03-11 2012-11-28 住友電気工業株式会社 Thin film superconducting wire and superconducting cable conductor
JP5727278B2 (en) * 2011-04-15 2015-06-03 住友電気工業株式会社 Manufacturing method of oxide superconducting thin film wire

Also Published As

Publication number Publication date
JP2015198009A (en) 2015-11-09

Similar Documents

Publication Publication Date Title
WO2016021343A1 (en) Oxide superconducting wire, superconducting device and method for producing oxide superconducting wire
JP5684961B2 (en) Oxide superconducting wire
US20190172612A1 (en) Oxide superconducting wire
JP6012658B2 (en) Oxide superconducting wire and manufacturing method thereof
JP2015146318A (en) Oxide superconducting wire, and method of manufacturing oxide superconducting wire
US9362026B2 (en) Oxide superconductor wire, connection structure thereof, and superconductor equipment
JP5847009B2 (en) Oxide superconducting wire
WO2013153973A1 (en) Oxide superconducting wire having reinforcing materials
JP6274975B2 (en) Oxide superconducting wire connecting structure manufacturing method and oxide superconducting wire connecting structure
JP6069269B2 (en) Oxide superconducting wire, superconducting equipment, and oxide superconducting wire manufacturing method
JP2014220194A (en) Oxide superconductive wire material and production method thereof
JP6751054B2 (en) Oxide superconducting wire, superconducting coil, and method for manufacturing oxide superconducting wire
JP2014130730A (en) Connection structure and connection method of oxide superconductive wire material, and oxide superconductive wire material using the connection structure
JP6232450B2 (en) Oxide superconducting wire
JP6461776B2 (en) Superconducting wire and method of manufacturing superconducting wire
JP7292257B2 (en) Superconducting wire connection structure and method for manufacturing superconducting wire connection structure
JP6484658B2 (en) Oxide superconducting wire and superconducting coil
JP2017152210A (en) Oxide superconducting wire and manufacturing method therefor
RU2575664C1 (en) Superconducting wire and superconducting coil
JP2013218914A (en) Oxide superconducting wire with reinforcement member
JP2014154331A (en) Oxide superconductive wire material, connection structure of oxide superconductive wire materials, and method for manufacturing an oxide superconductive wire material
JP2014167847A (en) Oxide superconducting wire and superconducting coil, and manufacturing method of oxide superconducting wire
JP2017069008A (en) Superconducting wire material
JP2017228388A (en) Oxide superconducting wire
JP2017010833A (en) Oxide superconducting wire material and manufacturing method of oxide superconducting wire material

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20151001

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20160531

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20160607

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20160801

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20160823

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20160920

R151 Written notification of patent or utility model registration

Ref document number: 6012658

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R151

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250