JPH03295208A - Manufacture of oxide superconducting coil wire material - Google Patents
Manufacture of oxide superconducting coil wire materialInfo
- Publication number
- JPH03295208A JPH03295208A JP2096415A JP9641590A JPH03295208A JP H03295208 A JPH03295208 A JP H03295208A JP 2096415 A JP2096415 A JP 2096415A JP 9641590 A JP9641590 A JP 9641590A JP H03295208 A JPH03295208 A JP H03295208A
- Authority
- JP
- Japan
- Prior art keywords
- oxide superconducting
- coil
- superconducting coil
- coil wire
- manufacturing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 14
- 239000000463 material Substances 0.000 title claims abstract description 9
- 239000013078 crystal Substances 0.000 claims abstract description 24
- 238000010438 heat treatment Methods 0.000 claims abstract description 20
- 238000000034 method Methods 0.000 claims abstract description 17
- 239000000843 powder Substances 0.000 claims abstract description 13
- 239000000203 mixture Substances 0.000 claims abstract description 10
- 238000004804 winding Methods 0.000 claims abstract description 4
- 229910052751 metal Inorganic materials 0.000 claims description 7
- 239000002184 metal Substances 0.000 claims description 6
- 239000000155 melt Substances 0.000 claims description 4
- 229910045601 alloy Inorganic materials 0.000 claims description 2
- 239000000956 alloy Substances 0.000 claims description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims 2
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims 2
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims 1
- 229910002092 carbon dioxide Inorganic materials 0.000 claims 1
- 239000001569 carbon dioxide Substances 0.000 claims 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims 1
- 229910052737 gold Inorganic materials 0.000 claims 1
- 239000010931 gold Substances 0.000 claims 1
- 238000004093 laser heating Methods 0.000 claims 1
- 229910052759 nickel Inorganic materials 0.000 claims 1
- 229910052763 palladium Inorganic materials 0.000 claims 1
- 229910052697 platinum Inorganic materials 0.000 claims 1
- 229910052709 silver Inorganic materials 0.000 claims 1
- 239000004332 silver Substances 0.000 claims 1
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 10
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract description 5
- 239000007788 liquid Substances 0.000 abstract description 5
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 5
- 229910001252 Pd alloy Inorganic materials 0.000 abstract description 2
- 239000006193 liquid solution Substances 0.000 abstract 2
- 238000007711 solidification Methods 0.000 description 6
- 230000008023 solidification Effects 0.000 description 6
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 description 4
- 239000011148 porous material Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 239000002887 superconductor Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 239000005751 Copper oxide Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 229910000431 copper oxide Inorganic materials 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- SWELZOZIOHGSPA-UHFFFAOYSA-N palladium silver Chemical compound [Pd].[Ag] SWELZOZIOHGSPA-UHFFFAOYSA-N 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/60—Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment
Landscapes
- Superconductors And Manufacturing Methods Therefor (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、一方向凝固法による酸化物超伝導コイル線材
の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing an oxide superconducting coil wire by a unidirectional solidification method.
従来、酸化物超伝導線材の製造方法については、ジャパ
ニーズ・ジャーナル囃オブ嘩アプライド・フィシツク２
２７巻・２号（１９８８）第５１８５頁から第５１８７
頁（Ｊａｐａｎｅｓｅ Ｊｏｕｒｎａｌ ｏｆＡｐ
ｐｌｉｅｄ Ｐｈｙｓｉｃｓ、 ２７．２． （１９
８８）ｐｐ、Ｌ１８５−Ｌ１８７）において論じられて
いるように、酸化物超伝導体の粉末を金属管内に充填後
、線引き加工や圧延加工等忙よって長尺の線材を製造す
るものである。Conventionally, methods for producing oxide superconducting wires have been described in Japanese Journal of Applied Physics 2.
Volume 27, No. 2 (1988), pages 5185 to 5187
Page (Japanese Journal of Ap
plied Physics, 27.2. (19
88) pp., L185-L187), after filling a metal tube with oxide superconductor powder, a long wire is manufactured by drawing, rolling, etc.
上記従来技術のコイル線材及び製造方法は、超伝導線材
に必要な臨界電流密度値が小さい、と）わけ磁界中にお
いて／ｊＳさいという問題があった。The above-mentioned prior art coil wire and manufacturing method have a problem in that the critical current density required for the superconducting wire is small, especially in a magnetic field.
酸化物超伝導コイル線材を応用するためには、この臨界
電流密度値Ｊｃを液体窒素温度（７７Ｋ）において、少
なくとも１テスラ（Ｔ）の磁界中で１０００Ａ／ａｍ２
以上に高める必要がある。In order to apply the oxide superconducting coil wire, this critical current density value Jc must be set to 1000 A/am2 at liquid nitrogen temperature (77 K) in a magnetic field of at least 1 Tesla (T).
It is necessary to raise this level even higher.
本発明の目的は、液体窒素温度における臨界電流密度値
ＪｃがＩＴＯ磁界中において、１０００Ａ ／ ｃｍ’
以上である酸化物超伝導コイル線材及びその製造方法を
提供することにある。The purpose of the present invention is to achieve a critical current density value Jc of 1000 A/cm' in an ITO magnetic field at liquid nitrogen temperature.
The object of the present invention is to provide an oxide superconducting coil wire material and a method for manufacturing the same.
上記目的を達成するため、酸化物超伝導結晶体の製造方
法において、その融液から一方向に酸化物超伝導結晶体
をコイル魂状に凝固させるようにしたものである。In order to achieve the above object, in a method for producing an oxide superconducting crystal, the oxide superconducting crystal is solidified from the melt into a coil shape in one direction.
すなわち、融液から所望の酸化物超伝導結晶が析出する
組成の粉末を金属管に充填し、コイル状に成形した後、
特定の温度勾配をもった熱処理炉中に入れコイルの巻き
方向と逆方向にコイルを回転させながらコイルの長手方
向に移動さることによυ、酸化物超伝導結晶体を一方向
に凝固させる方法である。融液から一方向凝固法
イル失地に所望の種子結晶を設置することで、酸化物超
伝導結晶の配向性多結晶体が得られるものである。That is, after filling a metal tube with powder having a composition that allows the desired oxide superconducting crystal to precipitate from the melt and forming it into a coil shape,
A method of solidifying an oxide superconducting crystal in one direction by placing it in a heat treatment furnace with a specific temperature gradient and moving it in the longitudinal direction of the coil while rotating it in the opposite direction to the winding direction of the coil. It is. An oriented polycrystalline body of oxide superconducting crystals can be obtained by placing desired seed crystals in the unidirectional solidification area of the melt.
所望の酸化物超伝導コイルの形状は、凝固前に行う、原
料粉末を充填した金属管の成形加工で達成される。コイ
ルを回転させながらコイルを長手方向に移動させるのは
、コイルの先端付近から順次、酸化物超伝導結晶体を凝
固させるためである。The desired shape of the oxide superconducting coil is achieved by forming a metal tube filled with raw material powder before solidification. The reason why the coil is moved in the longitudinal direction while being rotated is to solidify the oxide superconducting crystal sequentially from the vicinity of the tip of the coil.
コイル先端に種子結晶を設置するのは、酸化物超伝導結
晶の配向性多結晶体を得やすくするためである。The reason why a seed crystal is placed at the tip of the coil is to make it easier to obtain an oriented polycrystalline oxide superconducting crystal.
融液の一方向凝固法で製造される結晶体は、焼結法で製
造される結晶体より本、気孔が少なく、結晶体の方位が
そろっている。気孔や結晶体の方位がそろっていないこ
とは、臨界電流値を低くする要因と考えられ、これらの
要因が少々い融液の一方向凝固法で製造される結晶体は
より大きな臨界電流値が得られる。Crystal bodies produced by the unidirectional melt solidification method have fewer pores and pores than crystal bodies produced by the sintering method, and the orientation of the crystal bodies is uniform. The fact that the orientation of pores and crystals are not aligned is thought to be a factor that lowers the critical current value, and crystals manufactured by the unidirectional solidification method of melt with a small amount of these factors have a larger critical current value. can get.
以下、本発明の一実施例を説明する〇
純度９９．９ ％の酸化イツトＩＪウムＹ２０．．炭酸
バリウムＢａＣＯ３、酸化銅Ｃｕ ａの各粉末を、ＹＢ
ａ２ＣＩＵ ０７−Ｘ （組成Ａ）、””２ Ｃｕ３０
ｙ−Ｘ ： Ｃｕ Ｏ＝１：３（モル比）（組成Ｃ）と
なる２種類の組成に秤量し、メノウ乳鉢とメノウ乳棒を
用いたらいかい機で混合し、混合物をそれぞれアルミナ
坩堝に入れて、９００℃で空気中において８時間加熱し
た後、それらを上記らいかい機で粉砕し、仮焼粉末を得
た。Hereinafter, one embodiment of the present invention will be described.〇 IJium oxide IJium Y20. with a purity of 99.9%. ．． Each powder of barium carbonate BaCO3 and copper oxide Cu a was
a2CIU 07-X (composition A), ""2 Cu30
y-X: Cu O = 1:3 (mole ratio) (composition C) was weighed into two compositions, mixed in a sieve machine using an agate mortar and an agate pestle, and each mixture was placed in an alumina crucible. After heating in air at 900° C. for 8 hours, they were crushed in the above-mentioned sieve machine to obtain calcined powder.
これらの原料粉末を外径６ ｍｍ 、内径５ｍｍ。These raw material powders have an outer diameter of 6 mm and an inner diameter of 5 mm.
長さ４００ｍｍの銀パラジウム合金パイプ１に次の順序
で充填した。最初に組成Ａの仮焼粉末をパイプ長さ１０
ｍｍに相当する１を、次に組成Ｃの仮焼粉末を１５ｍ
ｍに相当する量を充填し、さらにその後、組成＾の仮焼
粉末を入れれるだけ入れたＯ
このようにして原料粉末を充填した釧ハラジウムパイプ
を外径２Ｃ１ｎｍのアルミナ管２に巻きつけてコイルを
成形した０このコイル成形物を以下の方法で局所加熱処
理を行った。A silver-palladium alloy pipe 1 having a length of 400 mm was filled in the following order. First, the calcined powder of composition A was heated to a pipe length of 10
1 corresponding to mm, then 15 m of calcined powder of composition C
After that, as much calcined powder of composition ^ was added as possible. O The Haradium pipe filled with the raw material powder in this way was wound around the alumina tube 2 with an outer diameter of 2C1 nm. This coil molded product was subjected to local heat treatment in the following manner.
局所加熱は、局所線状集光方式の赤外線イメージ熱処理
炉５を用い、局部加熱ヒータ８のスポット径を５ｍｍ
として行った。なお、熱処理温度を熱電対でモニタしな
がら熱処理を行った。コイル線材はアルミナ管に巻き付
けたまま、モータ３の駆動により、動力伝達部４を介し
て回転と水平移動が可能な構成とした。For local heating, an infrared image heat treatment furnace 5 with a local linear condensing method is used, and the spot diameter of the local heater 8 is set to 5 mm.
I went as. Note that the heat treatment was performed while monitoring the heat treatment temperature with a thermocouple. The coil wire was configured to be able to rotate and horizontally move via the power transmission section 4 by driving the motor 3 while being wound around the alumina tube.
初めに、局所加熱の位置に、コイル先端から１０ｍｍ離
れたコイル線材部分が設置されるようにモータの駆動に
よシ、回転と水平移動を行った。次に、局所加熱温度を
１０４０°Ｃに設置し、その温度まで、１０℃／ ！１
１ｉｎの昇温速度で昇温した。この状態で１ｈ保持した
。その後、コイル巻線と逆方向に、１ｊＬ５ｈで１回転
する速度で回転させるとともに、同時間でコイル１巻分
の水平移動を行った。コイルの回転と水平移動を約ａｏ
ｈ行った所、コイルの末端付近が局所加熱の位置に来た
ので、加熱を止め、１０℃／ ｍｉｎの降温速度で降温
し九〇
上記の熱処理によって得られたコイル線材の両端を線材
長さとして２０ ｍｍずつ切除し、臨界電流密度ＪＣ測
定を行った。ＪＣ値は、４端子法によって求めた値であ
シ、電圧端子間１ｏｍＫ１μＶ発生したときの電流で定
義した。液体窒素温度７７に、ＩＴ（テスラ）の磁界の
下でＪＣは１ｉ０Ａ／ａｍ２であった◎
コイル線材の長手方向の断面及び長手方向に垂直な断面
を観察した結果、気孔の少ない、柱状結晶の集合体とな
っていることがわかった。おそらく、酸化物超伝導体Ｙ
Ｂ’ａ２ ｃｕ、 ｏ、 ｚの臨界電流密度値が大きい
結晶軸のａ軸またＦｉｂ軸に配向していると思われる。First, the coil wire was rotated and moved horizontally by driving a motor so that the coil wire portion was placed 10 mm away from the tip of the coil at the local heating position. Next, set the local heating temperature to 1040°C, and increase the temperature by 10°C/! 1
The temperature was increased at a rate of 1 inch. This state was maintained for 1 hour. Thereafter, it was rotated in the opposite direction to the coil winding at a speed of one rotation in 1jL5h, and horizontally moved by one turn of the coil in the same time. The rotation and horizontal movement of the coil is approximately ao
When the coil wire was heated, the area near the end of the coil came to the position of local heating, so the heating was stopped and the temperature was lowered at a cooling rate of 10℃/min. A section of 20 mm was removed and critical current density JC was measured. The JC value was determined by the four-terminal method, and was defined as the current when a voltage of 1 umK 1 μV was generated between the terminals. The JC was 1i0A/am2 under the IT (Tesla) magnetic field at a liquid nitrogen temperature of 77%. ◎ As a result of observing the longitudinal cross section of the coil wire material and the cross section perpendicular to the longitudinal direction, it was found that the coil wire had columnar crystals with few pores. It turned out that it was a collective. Probably oxide superconductor Y
It is thought that B'a2 cu, o, and z are oriented along the a axis or the Fib axis of the crystal axes where the critical current density values are large.
本発明によれば、液体窒素温度における臨界電流密度値
が１！の磁界中において、１００ＯＡ／ａｍ２以上を有
する酸化物超伝導コイル線材及びその製造方法が得られ
る。これだより、酸化物系高温超伝導体の産業上の新規
な応用分野を關＜、顕著な効果を有する。According to the present invention, the critical current density value at liquid nitrogen temperature is 1! In a magnetic field of 100 OA/am2 or more, an oxide superconducting coil wire material and a method for manufacturing the same can be obtained. This newsletter has a remarkable effect on new industrial application fields of oxide-based high-temperature superconductors.
第１図は本発明の一方向凝固法による酸化物超伝導コイ
ル線材の製造方法の原理図、第２図は第１図のＩ−１線
断面図である。
１・・・合金パイプ、２・・・アルミナ管、３・・・モ
ータ、４・・・動力伝達部、５・・・熱処理炉、６・・
・回転方向、７・・・水平移動方向、８・・・局部加熱
ヒータ。FIG. 1 is a principle diagram of a method for manufacturing an oxide superconducting coil wire by the unidirectional solidification method of the present invention, and FIG. 2 is a sectional view taken along the line I-1 in FIG. 1. DESCRIPTION OF SYMBOLS 1... Alloy pipe, 2... Alumina pipe, 3... Motor, 4... Power transmission part, 5... Heat treatment furnace, 6...
- Rotation direction, 7... Horizontal movement direction, 8... Local heating heater.
Claims (5)
液から所望の酸化物超伝導結晶が析出する組成の粉末を
金属管に充填し、コイル状に成形した後、特定の温度公
配をもった熱処理炉に入れ、コイルの巻き方向と逆方向
にコイルを回転させながらコイルの長手方向に移動させ
ることにより、酸化物超伝導結晶体を一方向に凝固させ
ることを特徴とする酸化物超伝導コイル線材の製造方法
。1. In a method for manufacturing oxide-based superconducting coil wire material, a metal tube is filled with powder having a composition that allows desired oxide superconducting crystals to precipitate from a melt, and after being formed into a coil shape, the powder is heated to a specific temperature distribution. An oxide superconducting coil characterized in that the oxide superconducting crystal is solidified in one direction by placing it in a heat treatment furnace and moving the coil in the longitudinal direction while rotating the coil in a direction opposite to the winding direction of the coil. A method of manufacturing wire rods.
種子結晶を設置したことを特徴とする酸化物超伝導コイ
ル線材の製造方法。2. 2. The method for producing an oxide superconducting coil wire according to claim 1, characterized in that a seed crystal is placed in a portion to be melted and solidified first.
を一部溶融させないで焼結体として、その焼結体を種子
結晶として用いることを特徴とする酸化物超伝導コイル
線材の製造方法。3. 2. The method for producing an oxide superconducting coil wire according to claim 1, characterized in that the end portion of the portion to be melted first is partially unmelted to form a sintered body, and the sintered body is used as a seed crystal.
金，パラジウム，ニッケルまたはこれらの金属元素の２
種以上を母合金とした金属を用いることを特徴とする酸
化物超伝導コイル線材の製造方法。4. In claim 1, the metal tube material is silver, gold, platinum, palladium, nickel or two of these metal elements.
1. A method for manufacturing an oxide superconducting coil wire material, characterized in that a metal containing at least one seed is used as a master alloy.
線等のランプ加熱もしくは炭酸ガス等のレーザ加熱など
の局所集光加熱源を用いることを特徴とする酸化物超伝
導コイル線材の製造方法。5. 2. The method for manufacturing an oxide superconducting coil wire according to claim 1, characterized in that a local condensed heating source such as infrared ray lamp heating or carbon dioxide gas laser heating is used as the heating source of the heat treatment furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2096415A JPH03295208A (en) | 1990-04-13 | 1990-04-13 | Manufacture of oxide superconducting coil wire material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2096415A JPH03295208A (en) | 1990-04-13 | 1990-04-13 | Manufacture of oxide superconducting coil wire material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03295208A true JPH03295208A (en) | 1991-12-26 |
Family
ID=14164345
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2096415A Pending JPH03295208A (en) | 1990-04-13 | 1990-04-13 | Manufacture of oxide superconducting coil wire material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03295208A (en) |
-
1990
- 1990-04-13 JP JP2096415A patent/JPH03295208A/en active Pending
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