JPH01226761A - Superconducting ceramic composition - Google Patents
Superconducting ceramic compositionInfo
- Publication number
- JPH01226761A JPH01226761A JP63054488A JP5448888A JPH01226761A JP H01226761 A JPH01226761 A JP H01226761A JP 63054488 A JP63054488 A JP 63054488A JP 5448888 A JP5448888 A JP 5448888A JP H01226761 A JPH01226761 A JP H01226761A
- Authority
- JP
- Japan
- Prior art keywords
- superconducting ceramic
- compsn
- composition
- rare earth
- ceramic composition
- 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
- 239000000919 ceramic Substances 0.000 title claims abstract description 29
- 239000000203 mixture Substances 0.000 title claims description 43
- 229910052689 Holmium Inorganic materials 0.000 claims abstract description 11
- 229910052761 rare earth metal Inorganic materials 0.000 claims abstract description 9
- 229910052727 yttrium Inorganic materials 0.000 claims abstract description 9
- KJZYNXUDTRRSPN-UHFFFAOYSA-N holmium atom Chemical compound [Ho] KJZYNXUDTRRSPN-UHFFFAOYSA-N 0.000 claims description 10
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract description 10
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 abstract description 6
- 229910052757 nitrogen Inorganic materials 0.000 abstract description 5
- QPLDLSVMHZLSFG-UHFFFAOYSA-N CuO Inorganic materials [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 abstract description 4
- JYTUFVYWTIKZGR-UHFFFAOYSA-N holmium oxide Inorganic materials [O][Ho]O[Ho][O] JYTUFVYWTIKZGR-UHFFFAOYSA-N 0.000 abstract description 2
- 239000007858 starting material Substances 0.000 abstract description 2
- RUDFQVOCFDJEEF-UHFFFAOYSA-N yttrium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Y+3].[Y+3] RUDFQVOCFDJEEF-UHFFFAOYSA-N 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 description 5
- 238000010304 firing Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000011812 mixed powder Substances 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- 239000010955 niobium Substances 0.000 description 2
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 description 2
- 239000002887 superconductor Substances 0.000 description 2
- ZSLUVFAKFWKJRC-IGMARMGPSA-N 232Th Chemical compound [232Th] ZSLUVFAKFWKJRC-IGMARMGPSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910052776 Thorium Inorganic materials 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 229960004643 cupric oxide Drugs 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- OWCYYNSBGXMRQN-UHFFFAOYSA-N holmium(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Ho+3].[Ho+3] OWCYYNSBGXMRQN-UHFFFAOYSA-N 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 150000002736 metal compounds Chemical class 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 229910001404 rare earth metal oxide Inorganic materials 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229910052709 silver Inorganic materials 0.000 description 1
- 239000004332 silver Substances 0.000 description 1
- 238000004513 sizing 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
- Compositions Of Oxide Ceramics (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
この発明は、核融合、電力発電装置、超高速コンピュー
タ用高速動作半導体素子、電線材料、強力磁石材料、加
速器、ざらには医療機器等に使用される超電導セラミツ
ウス組成物に関するものである。[Detailed Description of the Invention] (Field of Industrial Application) This invention is applicable to nuclear fusion, power generation equipment, high-speed operating semiconductor elements for ultra-high-speed computers, electric wire materials, strong magnetic materials, accelerators, medical equipment, etc. The present invention relates to the superconducting ceramic composition used.
（従来の技術）
Ｎｂ（ニオブ）を含む物質等から成る従来の超電導体と
比較して、超電導現象を示す温度が高い超電導セラミッ
クス組成物についての研究が、最近精力的に行なわれで
いる。その理由は、高温で超電導現象が生じればそれだ
け冷却機構が簡易になり、このため、超電導現象の利点
を種々の分野へ波及させることが容易になるからである
。(Prior Art) Research has recently been actively conducted on superconducting ceramic compositions that exhibit superconducting phenomena at a higher temperature than conventional superconductors made of materials containing Nb (niobium). The reason for this is that the higher the superconducting phenomenon occurs at high temperatures, the simpler the cooling mechanism becomes, which makes it easier to spread the benefits of the superconducting phenomenon to various fields.
このような超電導セラミックス組成物としで、例えば文
献Ｉ ： ’Ｊａｐａｎｅｓｅ Ｊｏｕｒｎａｌ Ｏｆ
ＡｐｐｌｉｅｄＰｈｙｓｉｃｓ（ジャパニーズ ジャ
ーナル オブ アプライド フィジックス）Ｊ （Ｖｏ
ｌ、２６．Ｎｏ、４．Ａｐｒｉｌ。Such superconducting ceramic compositions are described in, for example, Document I: 'Japanese Journal of
Applied Physics (Japanese Journal of Applied Physics) J (Vo
l, 26. No, 4. April.
１９８７、ｐｐ、Ｌ３４７− Ｌ３４８）に開示される
Ｈｏ−Ｂａ−Ｃｕ−０系セラミツクスが知られている。1987, pp. L347-L348) is known.
この文献Ｉに開示される超電導セラミックス組成物では
、電気抵抗が実質的に零となる温度（ＶＡ界温度ＴＣ）
として、高いものでも約７６Ｋ（但し、）ｌｏ ： Ｂ
ａ ： Ｃｕ＝０．２４６：０．３３６： １の組成比
を有する。）であった。In the superconducting ceramic composition disclosed in this document I, the temperature at which the electrical resistance becomes substantially zero (VA field temperature TC)
As for the high one, it is about 76K (However,) lo: B
a: Cu has a composition ratio of 0.246:0.336:1. )Met.
また、例えば文献Ｈ： ｒＪａｐａｎｅｓｅ Ｊｏｕｒ
ｎａｌ ０ｆＡｐｐｌｉｅｄ Ｐｈｙｓｉｃｓ （ジ
ャパニーズ ジャーナルオブ アプライド フィジック
ス）Ｊ （ＶＯｌ、２６．ＮＯ。Also, for example, Document H: rJapanese Jour
nal 0fApplied Physics (Japanese Journal of Applied Physics) J (VOl, 26.NO.
４、＾ｐｒｉ１，１９８７．ｐｐ、Ｌ４５４− Ｌ４５
５）に開示されるＹ −８ａ−Ｃｕ−○系セラミックス
では、臨界温度Ｔｃが約８３Ｋ（但し、Ｙ ：Ｂａ：Ｃ
ｕ＝ １ ： ２ ： ３の組成比を有する。）である
。4, ^pri1, 1987. pp, L454-L45
In the Y-8a-Cu-○ ceramics disclosed in 5), the critical temperature Tc is approximately 83K (however, Y:Ba:C
It has a composition ratio of u=1:2:3. ).
（発明か解決しようとする課題）
しかしながら、上述した種々の組成を有する従来の超電
導セラミックス組成物が有する臨界温度Ｔ。においで、
これら組成物の利用分野の拡大を図るためには、当該臨
界温度Ｔｃを少なくとも液体窒素温度（７７Ｋ）以上と
する必要が有る。即ち、超電導体を種々の分野に応用し
ようとした場合、臨界温度Ｔｃは高い程好ましく、例え
ば上述の液体窒素温度以上の温度で超電導現象が生じる
ような物質が得られれば、従来の液体ヘリウム（４，２
Ｋ） ！始めとする冷却媒体に比へで、液体窒素が安価
であること等の理由から、非常に好適である。(Problems to be Solved by the Invention) However, the critical temperature T of the conventional superconducting ceramic compositions having the various compositions described above. Smell it,
In order to expand the field of application of these compositions, it is necessary to make the critical temperature Tc at least equal to or higher than the liquid nitrogen temperature (77K). That is, when trying to apply superconductors to various fields, the higher the critical temperature Tc is, the better. 4,2
K)! Compared to other cooling media, liquid nitrogen is very suitable because it is inexpensive.
また、このような超電導性をデバイス等に応用して機能
させるに当り、実用に適した超電導セラミックス組成物
のＴｃは、用いる冷媒の温度より高いほどデバイスの動
作マージンに余裕が生じ、望ましい。In addition, when applying such superconductivity to devices and the like, it is desirable that the Tc of a superconducting ceramic composition suitable for practical use be higher than the temperature of the coolant used, since this provides a margin for device operation.
この発明は、上述した点に鑑み成されたものであり、種
々の用途に供するため、超電導性を発現する臨界温度Ｔ
ｃが液体窒素温度（約７７Ｋ）以上である新規な超電導
セラミックス組成物を提供することを目的とする。This invention has been made in view of the above-mentioned points, and in order to serve various purposes, it is possible to improve the critical temperature T at which superconductivity is developed.
The present invention aims to provide a novel superconducting ceramic composition in which c is equal to or higher than the liquid nitrogen temperature (approximately 77 K).
（課題を解決するための手段）
この目的の達成を図るため、この発明の超電導セラミッ
クス組成物によれば、
Ｒ８ａ２Ｃｕ３０Ｘ（但し、日は希土類元素、６＜Ｘ〈
７）で表される超電導セラミックス組成物において、
上述した組成式中の日が、イツトリウム（Ｙ）とホルミ
ウム（Ｈａ）とから構成される（但し、これら２つの元
素のうち、いずれかが０モルである場合を含まず。）
ことを特徴としでいる。(Means for Solving the Problems) In order to achieve this object, according to the superconducting ceramic composition of the present invention, R8a2Cu30X (where 1 is a rare earth element and 6<X<
In the superconducting ceramic composition represented by 7), the number in the above compositional formula is composed of yttrium (Y) and holmium (Ha) (provided that either of these two elements is 0 mol). ).
（作用）
この発明の超電導セラミックス組成物によれば、従来、
日として一種類の希土類元素を用いていたものを、イツ
トリウム（Ｙ）とホルミウム（Ｈａ）との二種類の希土
類元素を用いる組成とすることにより、従来の超電導セ
ラミックス組成物に比して高いＴｃを実現できる。(Function) According to the superconducting ceramic composition of the present invention, conventionally,
By changing the composition that used one type of rare earth element to a composition that uses two types of rare earth elements, yttrium (Y) and holmium (Ha), it has a higher Tc than conventional superconducting ceramic compositions. can be realized.
（実施例）
以下、この発明の超電導セラミックス組成物の実施例に
つき説明する。(Examples) Examples of the superconducting ceramic composition of the present invention will be described below.
裂泣方」
まず、この発明の超電導セラミックス組成物の特性評価
を行なうための試料を以下に説明するような製造方法で
作製した。尚、以下の説明においては、この種の組成物
の製造工程で通常行なわれているバインダの混合や整粒
等の工程についでは省略して説明している。また、以下
に説明する １・製造方法中では、焼成温度、成形圧力
、焼成時間及び試料寸法またはその他の数値的条件は、
この発明の理解を容易とするため、好適な条件を例示し
であるに過ぎず、従って、この発明の目的は、これら特
定の条件によってのみ達成されるものではないことを理
解されたい。First, samples for evaluating the characteristics of the superconducting ceramic composition of the present invention were prepared using the manufacturing method described below. In the following description, steps such as binder mixing and sizing, which are normally carried out in the manufacturing process of this type of composition, are omitted. In addition, as explained below: 1. In the manufacturing method, the firing temperature, molding pressure, firing time, sample size, and other numerical conditions are as follows:
It should be understood that the preferred conditions are merely illustrative to facilitate understanding of the present invention, and therefore, the objectives of the present invention are not achieved solely by these specific conditions.
まず始めに、出発原料として、夫々の！４１！度が９９
．９％である炭酸バリウム（ＢａＣ０３）及び酸化第二
銅（Ｃｕｂ）を用意し、主成分については、ＲＢａｚＣ
ｕ３０ ｘで示される組成式に従って精秤した。また、
この発明の特徴となるイツトリウムについては酸化イツ
トリウム（Ｙ２Ｏ２）！用い、ホルミウム（Ｈａ）につ
いては酸化ホルミウム（Ｈａ□０３）ヲ用いた。これら
２つの希土類酸化物は、上述した組成式を満足するよう
に、後述の表■に掲げる夫々の組成比を以って試料毎に
精秤した。First of all, as a starting material, each! 41! degree is 99
．． 9% barium carbonate (BaC03) and cupric oxide (Cub) were prepared, and the main components were RBazC
It was accurately weighed according to the composition formula shown as u30x. Also,
Yttrium, which is a feature of this invention, is yttrium oxide (Y2O2)! As for holmium (Ha), holmium oxide (Ha□03) was used. These two rare earth oxides were precisely weighed for each sample using the respective composition ratios listed in Table 2 below so as to satisfy the above-mentioned compositional formula.
然る竣、上述した４ｆ！類の金属化合物をメノウ製の乳
鉢または播潰機を用いて約１時間に亙って充分に混合す
ることにより、夫々の組成比を有する混合粉を得る。Just completed, the above 4f! Mixed powders having the respective composition ratios are obtained by sufficiently mixing the metal compounds of the following types for about 1 hour using an agate mortar or a crusher.
次いで、これら混合粉の夫々を、空気雰囲気中、約９０
０℃の温度で５時間に亙って焼成し、仮焼物を得る。Next, each of these mixed powders was heated to about 90% in an air atmosphere.
A calcined product is obtained by firing at a temperature of 0° C. for 5 hours.
続いて、前述の播潰機等を用いて上述の仮焼物を粉砕し
、仮焼粉とした後、金型と油圧プレスとを用いて１〜３
ｔｏｎ／ｃｍ２の成形圧力を以って成形し、直径２４
ｍｍで厚さ３ｍｍの円板状の成形体を得た。Subsequently, the above-mentioned calcined product is crushed using the above-mentioned crusher, etc. to form a calcined powder, and then 1 to 3
Molded with molding pressure of ton/cm2, diameter 24
A disc-shaped molded body with a thickness of 3 mm was obtained.
このようにして得られた成形体を、空気雰囲気中、約９
５０℃の温度で２０時間に亙って焼成し、表Ｉ（後述）
に示す、試料番号■〜■のセラミックス組成物を得た。The molded body thus obtained was placed in an air atmosphere for about 90 minutes.
Baked at a temperature of 50°C for 20 hours, Table I (described below)
Ceramic compositions with sample numbers (■) to (■) shown in (1) to (2) were obtained.
臨 温１ の沖
次に、上述した製造方法によって得られたセラミックス
組成物に関し、各組成物の温度に対する抵抗の変化を測
定した。Next, regarding the ceramic compositions obtained by the above-mentioned manufacturing method, changes in resistance with respect to temperature of each composition were measured.
この実施例の場合、この抵抗の測定は、銅線で構成した
電極を銀ペーストによって各セラミックス組成物より成
る前述の成形体夫々に接続し、４端子法によって定電流
下でセラミックス組成物の所定の地点間の電圧変化を測
定することにより行なった。このような測定において、
電気抵抗が実質的に零となる温度をＴｃとした。In the case of this example, the resistance was measured by connecting an electrode made of a copper wire to each of the above-mentioned molded bodies made of each ceramic composition using silver paste, and using a four-terminal method to measure the predetermined value of the ceramic composition under constant current. This was done by measuring the voltage change between points. In such measurements,
The temperature at which the electrical resistance becomes substantially zero was defined as Tc.
以下、前述の製造方法により作製した試料番号■〜■の
仕込組成と、前述の測定方法により測定した臨界温度Ｔ
ｃとを表Ｉとしで示す、 −表工
但し、＊は、この発明の請求の範囲外の比較例であるこ
とを以下、前記表■を参照して、この発明の実施例に係
る超電導セラミックス組成物の特性につき説明する。Below, the preparation composition of sample numbers ■ to ■ produced by the above-mentioned manufacturing method and the critical temperature T measured by the above-mentioned measurement method are shown below.
c and are shown in Table I. However, * indicates a comparative example outside the scope of the claims of this invention. The characteristics of the composition will be explained.
表工からも理解できるように、前述した組成式のＲがイ
ツトリウム（Ｙ）のみで構成される従来構成の試料番号
■に係る試料では、Ｔｏが８２にであった。これと同様
に、日がホルミウム（ＨＯ）のみで構成される試料番号
■に係る試料では、Ｔｃが８３にである。As can be understood from the surface finish, To was 82 in the sample No. 2, which had a conventional structure in which R in the compositional formula described above was composed of only yttrium (Y). Similarly, Tc is 83 in the sample No. 3, which is composed only of holmium (HO).
これに対して、日が２種類の希土類元素を以って構成さ
れる試料番号■〜■では、この表Ｉからも理解できるよ
うに、８６〜８９にのＴ。を示し、上述した従来周知の
超電導セラミックス組成物に比して、３〜７ ｄｅ９程
度のＴ。向上を図ることができた。On the other hand, as can be understood from Table I, in sample numbers ■ to ■, in which days are composed of two types of rare earth elements, T is 86 to 89. T of about 3 to 7 de9 compared to the conventionally known superconducting ceramic compositions mentioned above. I was able to improve my performance.
上述した結果から、この発明の超電導セラミ・ンクス組
成物では、前述のＲ％イ・ントリウム及びホルミウムの
、２種類の希土類元素で構成することにより、従来より
も高いＴ。を達成し得ることがわかる。From the above results, the superconducting ceramic ink composition of the present invention has a higher T than the conventional one by being composed of two rare earth elements, thorium and holmium. It can be seen that this can be achieved.
尚、この発明は上述した実施例にのみ限定されるもので
はないこと明らかである。It is clear that the present invention is not limited only to the embodiments described above.
例えば、上述の実施例では、この発明に係る超電導セラ
ミックス組成物につき、試料番号■〜■として示す所定
の組成を例示して説明した。For example, in the above-mentioned Examples, predetermined compositions shown as sample numbers (■) to (■) were exemplified and explained for the superconducting ceramic composition according to the present invention.
しかしながら、この発明は、これら組成にのみ限定され
るものではなく、イツトリウムとホルミウムとの組成の
うちのいずれかがＯである場合を除き、これら２つの元
素のモル組成比の和が１となる組成であれば、上述と同
様の効果を期待し得る。However, the present invention is not limited only to these compositions, and unless either of the compositions of yttrium and holmium is O, the sum of the molar composition ratios of these two elements is 1. If the composition is suitable, effects similar to those described above can be expected.
（発明の効果）
上述した説明からも明らかなように、この発明の超電導
セラミックス組成物によれば、前述した組成式中の希土
類元素を示すＲＶイツトリウム（Ｙ）とホルミウム（Ｈ
Ｏ）との２種類により構成する。これがため、従来構成
の超電導セラミックス組成物に比して高いＴ。を実現で
きる。(Effects of the Invention) As is clear from the above explanation, according to the superconducting ceramic composition of the present invention, RV yttrium (Y) and holmium (H
It consists of two types: O). Therefore, T is higher than that of a superconducting ceramic composition having a conventional structure. can be realized.
従って、種々の分野への応用が可能になり、その工業的
利用価値は非常に大きいと云える。Therefore, it can be applied to various fields, and its industrial utility value can be said to be very large.
Claims (1)
元素、６＜Ｘ＜７）で表される超電導セラミックス組成
物において、 前記Ｒがイットリウム（Ｙ）とホルミウム（Ｈｏ）とか
ら構成される ことを特徴とする超電導セラミックス組成物。(1) A superconducting ceramic composition represented by RBa_2Cu_3O_x (where R is a rare earth element and 6<X<7), characterized in that the R is composed of yttrium (Y) and holmium (Ho). Superconducting ceramic composition.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63054488A JPH01226761A (en) | 1988-03-08 | 1988-03-08 | Superconducting ceramic composition |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63054488A JPH01226761A (en) | 1988-03-08 | 1988-03-08 | Superconducting ceramic composition |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01226761A true JPH01226761A (en) | 1989-09-11 |
Family
ID=12972030
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63054488A Pending JPH01226761A (en) | 1988-03-08 | 1988-03-08 | Superconducting ceramic composition |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01226761A (en) |
-
1988
- 1988-03-08 JP JP63054488A patent/JPH01226761A/en active Pending
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