JPH0248475A - Production of superconducting porous material - Google Patents
Production of superconducting porous materialInfo
- Publication number
- JPH0248475A JPH0248475A JP63197504A JP19750488A JPH0248475A JP H0248475 A JPH0248475 A JP H0248475A JP 63197504 A JP63197504 A JP 63197504A JP 19750488 A JP19750488 A JP 19750488A JP H0248475 A JPH0248475 A JP H0248475A
- Authority
- JP
- Japan
- Prior art keywords
- superconducting
- organic binder
- temperature
- porous material
- porous body
- 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 description 6
- 239000011148 porous material Substances 0.000 title abstract description 13
- 239000000463 material Substances 0.000 claims abstract description 28
- 239000000843 powder Substances 0.000 claims abstract description 21
- 239000011230 binding agent Substances 0.000 claims abstract description 20
- 238000000354 decomposition reaction Methods 0.000 claims abstract description 8
- 239000004088 foaming agent Substances 0.000 claims description 12
- 238000010304 firing Methods 0.000 claims description 9
- 238000005187 foaming Methods 0.000 claims description 5
- 238000004898 kneading Methods 0.000 claims description 4
- 239000000203 mixture Substances 0.000 abstract description 6
- 239000011159 matrix material Substances 0.000 abstract description 5
- 239000002887 superconductor Substances 0.000 abstract description 5
- 238000002156 mixing Methods 0.000 abstract description 4
- 239000004925 Acrylic resin Substances 0.000 abstract description 3
- 229920000178 Acrylic resin Polymers 0.000 abstract description 3
- 238000001816 cooling Methods 0.000 abstract description 3
- 239000000112 cooling gas Substances 0.000 abstract 1
- 239000003507 refrigerant Substances 0.000 abstract 1
- 238000000034 method Methods 0.000 description 10
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 239000010949 copper Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 230000001590 oxidative effect Effects 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000001099 ammonium carbonate Substances 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
- IWOUKMZUPDVPGQ-UHFFFAOYSA-N barium nitrate Chemical compound [Ba+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O IWOUKMZUPDVPGQ-UHFFFAOYSA-N 0.000 description 2
- 239000013590 bulk material Substances 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 229910052758 niobium Inorganic materials 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 229910052727 yttrium Inorganic materials 0.000 description 2
- NGDQQLAVJWUYSF-UHFFFAOYSA-N 4-methyl-2-phenyl-1,3-thiazole-5-sulfonyl chloride Chemical compound S1C(S(Cl)(=O)=O)=C(C)N=C1C1=CC=CC=C1 NGDQQLAVJWUYSF-UHFFFAOYSA-N 0.000 description 1
- 229910000013 Ammonium bicarbonate Inorganic materials 0.000 description 1
- 239000004604 Blowing Agent Substances 0.000 description 1
- 229910052692 Dysprosium Inorganic materials 0.000 description 1
- 229910052691 Erbium Inorganic materials 0.000 description 1
- 229910052693 Europium Inorganic materials 0.000 description 1
- 229910052688 Gadolinium Inorganic materials 0.000 description 1
- 229910052689 Holmium Inorganic materials 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- 229910052772 Samarium Inorganic materials 0.000 description 1
- 235000012538 ammonium bicarbonate Nutrition 0.000 description 1
- 235000012501 ammonium carbonate Nutrition 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- XTVVROIMIGLXTD-UHFFFAOYSA-N copper(II) nitrate Chemical compound [Cu+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O XTVVROIMIGLXTD-UHFFFAOYSA-N 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012770 industrial material Substances 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 230000002250 progressing effect Effects 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
Abstract
Description
【発明の詳細な説明】
（イ）産業上の利用分野
本発明は磁気シールド材等として利用することができる
超電導多孔体の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a method for manufacturing a superconducting porous body that can be used as a magnetic shielding material or the like.
（ロ）従来の技術
ＮｂあるいはＮｂ系合金よりなる超電導物質を利用した
工業材料の例として、超電導磁気シールド材が特開昭６
２−１０５４８７号公報に提案されている。しかし、Ｎ
ｂあるいはＮｂ系合金よりなる超電導物質は液体ヘリウ
ム温度（４，２Ｋ ）下で超電導状態になるため、冷
却の困難さがその実用化を遅らせている。(b) Conventional technology As an example of an industrial material using a superconducting substance made of Nb or a Nb-based alloy, a superconducting magnetic shielding material was published in Japanese Patent Laid-Open No. 6
This method is proposed in Japanese Patent No. 2-105487. However, N
Since superconducting materials made of Nb or Nb-based alloys become superconducting at liquid helium temperatures (4.2 K), the difficulty of cooling has delayed their practical application.
一方、近年液体窒素温度（７７Ｋ）以上の温度で超電導
状態を示す酸化物超電導物質が発見され、その実用化研
究が進められている。しかし現状においては、超電導物
質を液体窒素に浸漬して超電導状態を得るものであり、
超電導物質の利用範囲が限られている。On the other hand, in recent years, oxide superconducting materials that exhibit a superconducting state at temperatures higher than liquid nitrogen temperature (77 K) have been discovered, and research on their practical use is progressing. However, at present, superconducting materials are immersed in liquid nitrogen to obtain superconducting state.
The scope of use of superconducting materials is limited.
（ハ）発明が解決しようとする問題点
従来の超電導体はいずれも超電導体の表面から冷却する
ものであり、大面積の超電導体の冷却が困難となる。(c) Problems to be Solved by the Invention All conventional superconductors are cooled from the surface of the superconductor, making it difficult to cool a large area superconductor.
本発明はかかる点に鑑み発明されたものにして、内部か
ら冷却することができる超電導多孔体を提供することを
解決課題とする。The present invention was devised in view of these points, and an object to be solved is to provide a superconducting porous body that can be cooled from the inside.
（ニ）問題点を解決するための手段
本発明は、超電導相を少なくとも一部に含む超電導材粉
末と低温分解性の有機バインダーを混練した後、有機バ
インダーの分解温度以上の温度にて混練物を焼成し、超
電導多孔体を形成することを特徴とする。(d) Means for Solving the Problems The present invention provides a method for kneading superconducting material powder containing at least a portion of a superconducting phase and a low-temperature decomposable organic binder, and then heating the kneaded product at a temperature equal to or higher than the decomposition temperature of the organic binder. The method is characterized in that it is fired to form a superconducting porous body.
また、第２の発明は、超電導相を少なくとも一部に含む
超電導粉末と低温無８Ｍ発泡剤を混練した後、この発泡
剤の発泡温度以上の温度にて混練物を焼成し、超電導多
孔体を形成することを特徴とする。Further, the second invention is to knead a superconducting powder containing at least a part of a superconducting phase and a low-temperature non-8M foaming agent, and then firing the kneaded product at a temperature higher than the foaming temperature of the foaming agent to form a superconducting porous body. It is characterized by forming.
（ホ）作 用
第１の発明においては、超電導材粉末と有機バインダー
との混練物を、有機バインダーの分解温度以上の温度に
て焼成することにより、有機バインダーが分解焼失し、
超電導体はマトリクス枠状となり、三次元的に連続した
空孔を有する多孔体となる。(E) Effect In the first invention, the organic binder is decomposed and burned away by firing the kneaded mixture of the superconducting material powder and the organic binder at a temperature higher than the decomposition temperature of the organic binder.
The superconductor becomes a matrix frame-like porous body having three-dimensionally continuous pores.
第２の発明においては、超電導材粉末と無機発泡剤との
混練物を、この発泡剤の発泡温度以上の温度にて焼成す
ることにより、無機発泡剤を発泡させて焼失させ５その
発泡焼失跡を三次元的に連続した空孔となし、マトリク
ス枠状の超電導多孔体を形成する。In the second invention, by firing a kneaded mixture of superconducting material powder and an inorganic foaming agent at a temperature higher than the foaming temperature of the foaming agent, the inorganic foaming agent is foamed and burned out. are made into three-dimensionally continuous pores to form a matrix frame-shaped superconducting porous body.
これらの多孔体は三次元的に連続した空孔を有するため
、この空孔に冷媒を流すことができ、マトリクス枠状の
超電導多孔体を内部から冷却することが可能となり、多
孔体の大型化も冷却上支障が少ないものとなる。Since these porous bodies have three-dimensionally continuous pores, a coolant can flow through these pores, making it possible to cool the matrix frame-shaped superconducting porous body from inside, which allows the porous body to become larger. Also, there will be less trouble in cooling.
（へ）実施例
［第１実施例］
本発明の第１実施例を第１図を参照して説明する。第１
図は製造工程図である。(f) Example [First Example] A first example of the present invention will be described with reference to FIG. 1st
The figure is a manufacturing process diagram.
硝酸イツトリウムＹ （Ｎ Ｏ３） ３ ５Ｈ２０、硝
酸バリウムＢａ（ＮＯ３）２、硝酸銅Ｃｕ （Ｎ Ｏｙ
）ｚ・３Ｈ２０を夫々水に溶解し、Ｙ、Ｂａ−Ｃｕがモ
ル比１：２：３になるように混合する（工程■）。つい
で蓚酸の水溶液をＢａ元素２モルに対し７モル加えて反
応させる（工程■）。Yttrium nitrate Y (N O3) 3 5H20, Barium nitrate Ba (NO3)2, Copper nitrate Cu (N Oy
) Z.3H20 is dissolved in water and mixed so that the molar ratio of Y and Ba-Cu is 1:2:3 (Step 2). Next, 7 mol of an aqueous solution of oxalic acid is added to 2 mol of Ba element to cause a reaction (Step 2).
この反応により共沈した沈殿物を濾過し水洗したのち、
十分乾燥させ（工程■）、酸化雰囲気中において９６０
度で約３時間仮焼成〈工程■）を行った。After filtering and washing the precipitate co-precipitated by this reaction,
Thoroughly dry (Step ■) and heat to 960°C in an oxidizing atmosphere.
Temporary firing (step ①) was performed for about 3 hours at 30°C.
これにて得られる塊状材料を乳鉢で粉砕後、さらにボー
ルミルで粉砕して平均粒径５μｍの粉末を得た（工程■
）。この粉末は仮焼成条件により少なくとも超電導相を
一部に含む超電導材粉末である。The resulting lumpy material was crushed in a mortar and then further crushed in a ball mill to obtain a powder with an average particle size of 5 μm (Step 1).
). This powder is a superconducting material powder that partially contains at least a superconducting phase depending on the pre-calcination conditions.
次に、この超電導材粉末１００部に対し、低温分解性の
有機バインダーとしてのアクリル樹脂を１００部添加し
く工程■）、ボールミルで混練した。この混！１！物を
所定形状、たとえば長さ５０ｎｙａ、中１０ｍｍ、厚み
５ｍにプレス圧力１．５トン／’ ｃｍ ２でプレス成
型した（工程■）。Next, 100 parts of an acrylic resin as a low-temperature decomposable organic binder was added to 100 parts of this superconducting material powder (Step (2)), and the mixture was kneaded in a ball mill. This mess! 1! The product was press-molded into a predetermined shape, for example, length 50 nya, medium 10 mm, and thickness 5 m at a press pressure of 1.5 tons/cm 2 (step ①).
この成型物を酸化雰囲気中で有機バインダーの分解温度
（１４０’Ｃ）以上の９８０℃で１時間焼成した後、酸
化雰囲気中で８００℃３時間焼成して本焼成したく工程
■）。この本焼成により有機バインダーが焼失し、超電
導多孔体を得た。この多孔体は平均空孔径は直径０．５
ｍであり、空孔率は５０％であった。また、この多孔体
は超電導状態を示す臨界温度が９０にであり、この多孔
体に臨界温度（９０Ｋ）以下のヘリウムガスを導入する
と、多孔体はマイスナー効果を示し、超電導状態である
ことを確認した。マイスナー効果を呈することから、こ
の多孔体が磁気シールド材として機能することがわかる
。This molded product is fired in an oxidizing atmosphere at 980°C, which is higher than the decomposition temperature of the organic binder (140'C), for 1 hour, and then fired at 800°C in an oxidizing atmosphere for 3 hours to carry out the main firing (Step (2)). By this main firing, the organic binder was burned out, and a superconducting porous body was obtained. The average pore diameter of this porous body is 0.5
m, and the porosity was 50%. In addition, this porous body has a critical temperature of 90°C which indicates a superconducting state, and when helium gas below the critical temperature (90K) is introduced into this porous body, the porous body exhibits the Meissner effect, confirming that it is in a superconducting state. did. The Meissner effect indicates that this porous body functions as a magnetic shielding material.
超電導多孔体の平均空孔径及び空孔率は、超電導材粉末
の粒径及び有機バインダーの添加量により調整すること
ができる。この多孔体の構造体としての強度及び超電導
特性を損なわないようにするためには、平均空孔径１ｎ
ｍ以下、空孔率８０％以下が望ましい。The average pore size and porosity of the superconducting porous body can be adjusted by adjusting the particle size of the superconducting material powder and the amount of the organic binder added. In order not to impair the strength and superconducting properties of this porous body as a structure, the average pore diameter must be 1n.
m or less, and the porosity is preferably 80% or less.
この実施例では低温分解性の有機バインダーとして、ア
クリル樹脂を用いたが、この他にポリビニールアルコー
ル（分解温度２００ ’Ｃ）を用いることもできる。In this example, acrylic resin was used as a low-temperature decomposable organic binder, but polyvinyl alcohol (decomposition temperature: 200'C) may also be used.
［第２実施例］
第１実施例の工程■で得た平均粒径５μｍの超電導材粉
末に、第１実施例の低温分解性有機バインダーに代えて
、低温無機発泡剤を添加し、その添加量を３０部にした
点を除いて、第１実施例と同一条件にて超電導多孔体を
形成した。[Second Example] A low-temperature inorganic foaming agent was added to the superconducting material powder having an average particle size of 5 μm obtained in step (1) of the first example in place of the low-temperature decomposable organic binder of the first example. A superconducting porous body was formed under the same conditions as in the first example except that the amount was changed to 30 parts.
低温無機発泡剤としては、炭酸水素アンモニウムを用い
たが、炭酸アンモニウムを使用してもよい。Although ammonium hydrogen carbonate was used as the low-temperature inorganic foaming agent, ammonium carbonate may also be used.
この第２実施例で得た超電導多孔体は、本焼成時に発泡
剤が８０°Ｃ位で発泡し、１００乃至２００℃位で焼失
することによって形成され、平均空孔径０ 、５ ｍｍ
、空孔率５０％であり、また臨界温度も第１実施例と
同じであった。The superconducting porous body obtained in this second example was formed by foaming the foaming agent at about 80°C during main firing and burning out at about 100 to 200°C, and had an average pore diameter of 0.5 mm.
, the porosity was 50%, and the critical temperature was also the same as in the first example.
尚、低温無機発泡剤の添加量を、超電導材粉末１００部
に対し、３０部としたが、１０乃至５０部用いてもでき
る。Although the amount of the low-temperature inorganic foaming agent added was 30 parts per 100 parts of the superconducting material powder, it is also possible to use 10 to 50 parts.
以上の実施例においては、超電導相を少なくとも一部に
含む超電導材粉末を、共沈法により塊状材料から得たが
、粉末混合法で得た塊状材料から得るようにしてもよい
。ここにいう粉末混合法とは、たとえばＬｎ２Ｏ３（Ｌ
ｎはＹ、Ｙｂ−Ｅｒ、Ｇｄ、Ｄｙ、Ｈｏ、Ｅｕ、Ｓｍ、
Ｎｄから選ばれるものである）とＢ ａ ＣＯ３とＣｕ
Ｏとを混合して加圧成型した後、酸化雰囲気中で焼結し
てＬｎＢ ａ ２Ｃｕ ３０７−δで表わされる組成か
らなる超電導材物質を得る方法を意味する。In the above examples, the superconducting material powder containing at least a portion of the superconducting phase was obtained from the bulk material by the coprecipitation method, but it may also be obtained from the bulk material obtained by the powder mixing method. The powder mixing method referred to here means, for example, Ln2O3 (L
n is Y, Yb-Er, Gd, Dy, Ho, Eu, Sm,
), B a CO3 and Cu
This refers to a method of obtaining a superconducting material having a composition represented by LnBa 2 Cu 307-δ by mixing with O and press-molding the mixture and then sintering it in an oxidizing atmosphere.
また超電導材粉末は超電導相を少なくとも一部に含むも
のであればよく、実施例の仮焼成においては、アニール
工程を十分にとっていないが、アニール処理により超電
導相の領域が前記粉末のほとんどを占めるものであって
もよいことは、いうまでもない。In addition, the superconducting material powder may contain at least a part of the superconducting phase, and although the annealing process is not sufficiently performed in the pre-firing of the example, the superconducting material powder should be one in which the superconducting phase region occupies most of the powder due to the annealing treatment. Needless to say, it may be.
（ト）発明の効果
発明によれば、超電導相を少なくとも一部に含む超電導
材粉末と低温分解性有機バインダー又は低温無機発泡剤
を混練した後、有機バインダーの分解温度又は発泡剤の
発泡温度以上の温度にて混練物を焼成し、超電導多孔体
を形成するものであるから、冷却ガスを用いてこの多孔
体の内部から冷却することも可能となり、冷却する上で
大型化も可能であり、磁気シールド材等に利用すること
ができる。(g) Effects of the invention According to the invention, after kneading a superconducting material powder containing at least a portion of a superconducting phase and a low-temperature decomposable organic binder or a low-temperature inorganic foaming agent, the temperature is higher than the decomposition temperature of the organic binder or the foaming temperature of the blowing agent. Since the kneaded material is fired at a temperature of It can be used for magnetic shielding materials, etc.
第１図は本発明の第１実施例の製造工程を示す工程図で
ある。FIG. 1 is a process diagram showing the manufacturing process of a first embodiment of the present invention.
Claims (2)
低温分解性の有機バインダーを混練した後、有機バイン
ダーの分解温度以上の温度にて混練物を焼成し、超電導
多孔体を形成することを特徴とする超電導多孔体の製造
方法。(1) After kneading a superconducting material powder containing at least a portion of a superconducting phase and a low-temperature decomposable organic binder, the kneaded material is fired at a temperature higher than the decomposition temperature of the organic binder to form a superconducting porous body. A method for producing a featured superconducting porous body.
低温無機発泡剤を混練した後、この発泡剤の発泡温度以
上の温度にて混練物を焼成し、超電導多孔体を形成する
ことを特徴とする超電導多孔体の製造方法。(2) A superconducting porous body is formed by kneading a superconducting material powder containing at least a portion of a superconducting phase and a low-temperature inorganic foaming agent, and then firing the kneaded product at a temperature equal to or higher than the foaming temperature of the foaming agent. A method for producing a superconducting porous body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63197504A JPH0248475A (en) | 1988-08-08 | 1988-08-08 | Production of superconducting porous material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63197504A JPH0248475A (en) | 1988-08-08 | 1988-08-08 | Production of superconducting porous material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0248475A true JPH0248475A (en) | 1990-02-19 |
Family
ID=16375575
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63197504A Pending JPH0248475A (en) | 1988-08-08 | 1988-08-08 | Production of superconducting porous material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0248475A (en) |
-
1988
- 1988-08-08 JP JP63197504A patent/JPH0248475A/en active Pending
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