JPH01215713A - Production of superconductor - Google Patents

Production of superconductor

Info

Publication number
JPH01215713A
JPH01215713A JP63042649A JP4264988A JPH01215713A JP H01215713 A JPH01215713 A JP H01215713A JP 63042649 A JP63042649 A JP 63042649A JP 4264988 A JP4264988 A JP 4264988A JP H01215713 A JPH01215713 A JP H01215713A
Authority
JP
Japan
Prior art keywords
superconductor
amount
replaced
stable
current density
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.)
Granted
Application number
JP63042649A
Other languages
Japanese (ja)
Other versions
JP2785263B2 (en
Inventor
Mutsuaki Murakami
睦明 村上
Susumu Yoshimura
吉村 進
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.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co 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 Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP63042649A priority Critical patent/JP2785263B2/en
Publication of JPH01215713A publication Critical patent/JPH01215713A/en
Application granted granted Critical
Publication of JP2785263B2 publication Critical patent/JP2785263B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/60Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment

Abstract

PURPOSE:To obtain a stable superconductor having high current density and high conductivity in a normal conduction state in production of a high- temperature superconductor of Y-Ba-Cu-O base, by replacing part of Ba with Sr and part of Cu with Ag at the same time. CONSTITUTION:Raw materials such as Ya2O3, BaCO3, SrCO3, CuO and Ag2O are weighed in the aromic ratio of Y:(Ba+Sr):(Cu+Ag) of 1:2:3, blended and ground. The amount of strontium replaced is properly 10-15wt.% based on 100wt.% Ba and the amount of silver replaced is properly 5-25wt.% based on 100wt.% copper. Then the ground raw materials are dried, press molded, calcined and annealed to give a superconductor. The prepared superconductor shows stable superconducting characteristics even after being allowed to stand in a room for several months.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、常伝導状態での電気伝導性にすぐれ、しかも
同時に安定な超電導特性を有する超電導体の製造方法の
改良に関するものである。
DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement in a method for manufacturing a superconductor that has excellent electrical conductivity in a normal state and also has stable superconducting properties.

従来の技術 最近、ランタニウム(La)−バ9ウム(Ba) −銅
(Cu)−酸素(0)あるいはイツトリウム(Y)−B
a −Cu −0から成る酸化物導電体が高い超電導移
点(Tc )を有すると言う重要な発見が為された。T
cとしては構成元素或は化合物組成の制御により30以
上100 K (−173℃)迄の値が報告されている
。特に、Y−Ba−Cu−0系(以下YBCOと略す)
では、3゛金属の原子比率が1=2:3の時最も高いT
cが得られ、電気抵抗がゼロとなる温度(Toffと略
す)は、最も再現性のあるデータで、95にであると言
われている。酸素の含有量に関しては、6.9程度であ
ろうと予想されている。更に、YBCO系でYをランタ
ニド系列元素(例えば、Lu 、 Yb 、 Tm 、
 Er 、 Ho 、 Dy 、 Gd 。
Conventional technology Recently, lanthanium (La) - barium (Ba) - copper (Cu) - oxygen (0) or yttrium (Y) - B
An important discovery has been made that oxide conductors consisting of a-Cu-0 have a high superconducting transition point (Tc). T
Values of c from 30 to 100 K (-173°C) have been reported by controlling the constituent elements or compound composition. In particular, Y-Ba-Cu-0 system (hereinafter abbreviated as YBCO)
Then, when the atomic ratio of 3゛metal is 1=2:3, the highest T
The temperature at which c is obtained and the electrical resistance becomes zero (abbreviated as Toff) is said to be 95, which is the most reproducible data. The oxygen content is expected to be around 6.9. Furthermore, in the YBCO system, Y is a lanthanide series element (for example, Lu, Yb, Tm,
Er, Ho, Dy, Gd.

Eu 、 Sm 、 Nd 、 La  )で置き換え
た化合物が多く合成されており、その大半が90 K以
上のTcを示している。この様に、高い温度で超電導を
示す酸化物導電体は、Cu−0を基本元素として含み、
イツトリウムあるいはランタニド元素およびアルカリ土
類元素により結晶構造及び電子状態をうまく制御された
ものであると言える。
Many compounds have been synthesized with substitutions (Eu, Sm, Nd, La), and most of them exhibit Tc of 90 K or higher. In this way, oxide conductors that exhibit superconductivity at high temperatures contain Cu-0 as a basic element,
It can be said that the crystal structure and electronic state are well controlled by yttrium or lanthanide elements and alkaline earth elements.

また、極最近オプシンスキー氏らは、フッ素を含むY−
Ba −Cu −0系酸化物に於て150 KのTof
fを認めている(フィジカル レビュー レターズ; 
Phys、Rev、 Lett、誌58巻2597頁(
1987年))。更に、他の元素を添加することにより
室温以上での超電導の兆しが見えたとの報告もある。
In addition, very recently, Opsinski et al.
Tof of 150 K in Ba-Cu-0 series oxide
admits f (Physical Review Letters;
Phys, Rev, Lett, Vol. 58, p. 2597 (
(1987)). Furthermore, there are reports that signs of superconductivity at temperatures above room temperature can be seen by adding other elements.

更に、江原氏らはY−Ba−8r −Cu −0カら成
る酸化物に於て、65℃で抵抗がゼロになる現象を報告
している(ジャパニーズ ジャーナル オブ ザ アプ
ライド フィツクス; Jpn、 J。
Furthermore, Ehara et al. have reported the phenomenon that the resistance becomes zero at 65°C in an oxide consisting of Y-Ba-8r-Cu-0 (Japanese Journal of the Applied Fixtures; Jpn, J.

Appl、 Phys、誌、26巻、頁、1987年)
Appl, Phys, vol. 26, p. 1987)
.

一方、これらの超電導体がエレクトニクスデバイスとし
て用いられるには超電導体が安定である事、超電導状態
で印加出来る電流密度が大きく取れる事などが大切であ
る。しかしながらセラミック超電導体の電流密度は超電
導体自体が粉体を焼結して製造されるため、その粉体界
面での抵抗のため大きく取れないのが普通である。
On the other hand, in order for these superconductors to be used as electronic devices, it is important that the superconductors be stable and that a large current density can be applied in the superconducting state. However, since the superconductor itself is manufactured by sintering powder, the current density of ceramic superconductors cannot normally be set to a large value due to resistance at the powder interface.

発明が解決しようとする課題 酸化物導電体の製造法は、焼結という固体反応に依存し
ているため、その生成物は非晶質体か多結晶体であるこ
とが多い。従って、高温超電導を安定に出現させるには
、化学組成ばかりでなく、焼結体の性質を制御する必要
がある。そのために、出発原料の粒径なできるだけ細か
くする事が先ず重要である。BaOの代わりにBa C
o aを用いるのはそのためであり、他の方法として、
共沈法で沈澱させた酸化物微粒子を用いるというのもあ
る。また、固体反応を効率よく進行させるために、原料
を粉砕混合した後に、粉末状態で長時間熱処理をする(
仮焼)ことが有効である。更に、焼結にあたっても、焼
結温度、時間、温度上昇−降下の制御、焼結雰囲気、等
に関して細かい制御が必要である。この様に従来の酸化
物導電体の製造法は、焼結体の性質を向上させるために
非常に複雑で、労を要する工法を必要としていた。
Problems to be Solved by the Invention Since the manufacturing method of oxide conductors relies on a solid-state reaction called sintering, the products are often amorphous or polycrystalline. Therefore, in order to stably produce high-temperature superconductivity, it is necessary to control not only the chemical composition but also the properties of the sintered body. For this purpose, it is first important to make the particle size of the starting material as fine as possible. BaC instead of BaO
That is why o a is used, and as another method,
There is also the use of oxide fine particles precipitated by a coprecipitation method. In addition, in order to make the solid-state reaction proceed efficiently, after the raw materials are pulverized and mixed, they are heat-treated for a long time in the powder state (
Calcining) is effective. Furthermore, during sintering, detailed control is required regarding sintering temperature, time, control of temperature rise and fall, sintering atmosphere, etc. As described above, conventional methods for producing oxide conductors require extremely complicated and labor-intensive construction methods in order to improve the properties of the sintered body.

本発明は、上記のようなY−Ba−Cu−0系セラミッ
クス超電導体の持つ課題を解決するもので、その目的の
第1は安定な超電導特性を示す超電導体を開発する事、
第2は高い電流密度を実現する事、第3は常伝導状態で
電気伝度度の高い材料を開発する事である。第3の点は
万一超電導状態が破れても発生する電流のジーール熱に
よって素子が破壊するのを防ぐために必要な特性である
The present invention is intended to solve the above-mentioned problems with Y-Ba-Cu-0 ceramic superconductors, and its first purpose is to develop a superconductor that exhibits stable superconducting properties.
The second goal is to achieve a high current density, and the third goal is to develop a material with high electrical conductivity in a normal conducting state. The third point is a necessary characteristic to prevent the element from being destroyed by the Zeel heat generated by the current even if the superconducting state is broken.

課題を解決するための手段 本発明は上記目的を達成するもので、その技術的な手段
は、本質的にY −Ba−Cu −0で構成される超電
導体のバリウム(Ba)の一部をストロンチウム(Sr
)ニ、銅(Cu)の一部を銀(AJ9)に同時に置換す
る製造方法にある。
Means for Solving the Problems The present invention achieves the above-mentioned object, and its technical means is to partially absorb barium (Ba) of a superconductor consisting essentially of Y-Ba-Cu-0. Strontium (Sr
) 2) A manufacturing method in which a part of copper (Cu) is replaced with silver (AJ9) at the same time.

作    用 本発明は、Y −Ba −Cu−0系セラミック超電導
体において、Baの一部をS「に置換し同時にCu  
の一部を幻に置換する事により、安定で、高い電流密度
と高い常伝導状態における電導度を有する超電導体を得
る事が出来る。
Function The present invention provides a Y-Ba-Cu-0 ceramic superconductor in which a part of Ba is replaced with S and at the same time Cu
By substituting a part of the superconductor with a phantom, it is possible to obtain a stable superconductor with high current density and high conductivity in the normal state.

実施例 本発明の超電導体の基本的な製造方法は次のとおりであ
る。メノウの乳鉢を用いて、最初に定めラレタ組成比〔
Y : (Ba +Sr ) : (Cu+AJ )の
原子比率がl:2:3であることを基準にする〕のY2
03、Ba COa、SrCO3、Cub、 A、!9
20を粉砕し、均一になるまで混合する。この時Ba 
CO3とSrCO3、CuOとA120  の重量比を
いろいろに変化させる。粉砕後、120℃以上の温度で
十分に乾燥させ、成型を行う。成型圧力は、500に9
/d以上であれば良かったが焼結体の均一性を考慮して
、一般には2,5t/dの圧力で成型した。作られたペ
レットの焼成は、通常の管状炉を用いて、空気中で行っ
た。焼成温度は、850から945℃の間が適当であっ
た。焼成後、800℃に10時間、400℃に10時間
放置してアニールを施した。この様ニジて得られたY 
−(Ba−1−8r ) −(Cu +AJ? )−〇
の焼結体は、添加物の量が適当である場合には95 K
で抵抗がゼロとなる超電導体であった超電導特性は非常
に安定で、Sr及びMを同時に添加した系は室内に3ケ
月間放置した後も安定な超電導特性を示した。この様な
安定な超電導特性を示し、なおかつ先にのべたすぐれた
電流密度、常伝導状態での高伝導性が実現出来るのは、
Ba100wt%に対するSrの添加量が10〜50 
wt%、Cu 100wt%に対するA、9の添加量が
5〜25wtチの場合であった。表1にはCuに対する
Mの添加量を10wt%に固定した場合のBa  に対
するSrの添加量が、超電導転移特性、電流密度、室温
電気伝導度の値に及ぼす影響を示す。また表2にはBa
に対するS「の添加量を2Qwt% に固定した場合の
Cuに対するAf!の添加量が超電導転移特性、安定性
、電流密度、室温電気伝導度の値に及ぼす影響を示す。
EXAMPLE The basic method for manufacturing the superconductor of the present invention is as follows. Using an agate mortar, first determine the Lareta composition ratio [
Y2: (based on the atomic ratio of (Ba + Sr): (Cu + AJ) being l:2:3)
03, Ba COa, SrCO3, Cub, A,! 9
Grind 20 and mix until homogeneous. At this time Ba
The weight ratios of CO3 and SrCO3 and CuO and A120 were varied. After pulverization, it is sufficiently dried at a temperature of 120° C. or higher, and then molded. Molding pressure is 500 to 9
It would have been better if the pressure was at least /d, but in consideration of the uniformity of the sintered body, molding was generally performed at a pressure of 2.5 t/d. Calcining of the pellets produced was carried out in air using a conventional tube furnace. The firing temperature was suitably between 850 and 945°C. After firing, it was left at 800°C for 10 hours and at 400°C for 10 hours for annealing. Y obtained in this way
-(Ba-1-8r) -(Cu +AJ?)-〇 sintered body can reach 95 K if the amount of additives is appropriate.
The superconducting properties of the superconductor, which was a superconductor with zero resistance, were very stable, and the system in which Sr and M were added at the same time showed stable superconducting properties even after being left indoors for three months. The reason why it is possible to exhibit such stable superconducting properties, and also achieve the excellent current density and high conductivity in the normal state is that
The amount of Sr added to 100 wt% of Ba is 10 to 50
The amount of A and 9 added to 100 wt% of Cu was 5 to 25 wt%. Table 1 shows the influence of the amount of Sr added to Ba on the superconducting transition characteristics, current density, and room temperature electrical conductivity when the amount of M added to Cu is fixed at 10 wt%. Table 2 also shows Ba
The effect of the amount of Af! added to Cu on the superconducting transition characteristics, stability, current density, and room temperature electrical conductivity is shown when the amount of S added to Cu is fixed at 2Qwt%.

以下余白 表1 表2 表1の結果はS「の添加量が10〜5Qwt%時にすぐ
れた超電導特性が得られる事を示している。また表2の
結果はA!iの添加量が5〜25wt%の時にすぐれた
超電導特性が得られる事を示し、しかもAyの添加が電
流密度の向上、室温電気伝導度の向上に著るしい効果が
ある事を示している。
The results in Table 1 show that excellent superconducting properties can be obtained when the amount of S'' added is 10 to 5 Qwt%.The results in Table 2 show that the amount of A!i added is 5 to 5 Qwt%. It is shown that excellent superconducting properties can be obtained when the content is 25 wt%, and furthermore, it is shown that the addition of Ay has a remarkable effect on improving current density and room temperature electrical conductivity.

以下にさらに詳細に述べる。Further details are provided below.

〔実施例 1〕 試薬として入手したY2O3、B20およびBaに対し
重量比が2QwL%に相当するSrを含む5rCOaC
uOおよびCuに対し重量比が19w1%に相当するA
IIを含むAIIzOをメノウの乳鉢で高純度エタノー
ルを滴下しつつ、完全に粉砕した。
[Example 1] 5rCOaC containing Sr at a weight ratio of 2QwL% to Y2O3, B20 and Ba obtained as reagents
A with a weight ratio of 19w1% to uO and Cu
AIIzO containing II was completely pulverized in an agate mortar while dropping high purity ethanol.

この粉末を501から10.9の間の重さとして秤量し
、直径13C111の成型治具の中に充填し加圧した。
This powder was weighed to have a weight between 501 and 10.9, and filled into a molding jig with a diameter of 13C111 and pressurized.

圧力は約2500に9/cdで、排気しつつ3゜分間行
った。このペレットを白金板の上に置き置き、管状炉の
中のにセットして熱処理を行った。
The pressure was approximately 2,500 to 9/cd for 3 minutes with evacuation. This pellet was placed on a platinum plate, set in a tube furnace, and heat treated.

例えば、4時間の熱処理の結果、900℃では8×10
S/crnであった。最高の電導度は900から940
℃の間の温度で得られ、1.lX1Oから1.5XIO
8/αであった。また、945℃以上の温度では、抵抗
が再び上昇する傾向が見られた(例えば980℃で約7
 X 10 S /an )。
For example, as a result of heat treatment for 4 hours, at 900℃, 8×10
It was S/crn. The highest conductivity is 900 to 940
obtained at temperatures between 1. lX1O to 1.5XIO
It was 8/α. In addition, at temperatures above 945°C, there was a tendency for the resistance to increase again (for example, at 980°C, about 7
X 10 S /an).

この様にして得られたペレットに銀ペーストで四端子電
極を取りつけ、その超電導特性を測定した。温度−抵抗
特性の測定結果を図に示す。抵抗値は室温から597に
付近まで序々に減少し、97により急激に降下した。9
5に以下ではゼロ抵抗を示し、完全な超電導状態になっ
た。
A four-terminal electrode was attached to the pellet thus obtained using silver paste, and its superconducting properties were measured. The measurement results of temperature-resistance characteristics are shown in the figure. The resistance value gradually decreased from room temperature to around 597, and then rapidly decreased to 97. 9
5 and below, it showed zero resistance and became a complete superconducting state.

この様にして作成した超電導体は非常に安定であり、空
気中、室温で3ケ月間放置し、再び温度−抵抗特性を測
定したが全く変化していなかった。
The superconductor thus prepared was very stable, and when it was left in the air at room temperature for 3 months and its temperature-resistance characteristics were measured again, no change was found.

発明の効果 以上要するに、本発明はY−Ba−Cu−0系の高温超
電導体の製造に於て、Baの一部をSrに置換し、同時
にCuの一部を、Uに置換する事を特徴とする新規な酸
化物超電導体を開示するもので、本発明によって、すぐ
れた安定性、高い電流密度、常伝導状態での高い電導塵
をかねてそなえた超電導体を得る事が出来る。
Effects of the Invention In short, the present invention involves replacing part of Ba with Sr and simultaneously replacing part of Cu with U in the production of Y-Ba-Cu-0 based high temperature superconductors. The present invention discloses a novel oxide superconductor with characteristics, and the present invention makes it possible to obtain a superconductor that has excellent stability, high current density, and high conductive dust in a normal conduction state.

【図面の簡単な説明】[Brief explanation of the drawing]

図はY (13a−8r ) (Cu −19) 0系
超電導体の温度−抵抗特性である。
The figure shows the temperature-resistance characteristics of the Y(13a-8r)(Cu-19)0-based superconductor.

Claims (2)

【特許請求の範囲】[Claims] (1)本質的にイットリウム、バリウム、銅、酸素から
形成され、バリウムの一部をストロンチウムに置換する
と同時に銅の一部を銀に置換する事を特徴とする超電導
体の製造方法。
(1) A method for producing a superconductor essentially formed from yttrium, barium, copper, and oxygen, characterized in that part of the barium is replaced with strontium and at the same time, part of the copper is replaced with silver.
(2)バリウム100wt%に対するストロンチウムの
置換量が10〜50wt%であり、銅100wt%に対
する銀の置換量が5〜25wt%の範囲にある事を特徴
とする請求項1記載の超電導体の製造方法。
(2) Production of the superconductor according to claim 1, characterized in that the amount of strontium substituted with respect to 100 wt% of barium is 10 to 50 wt%, and the amount of silver substituted with respect to 100 wt% of copper is in the range of 5 to 25 wt%. Method.
JP63042649A 1988-02-25 1988-02-25 Superconductor manufacturing method Expired - Lifetime JP2785263B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
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Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
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Publications (2)

Publication Number Publication Date
JPH01215713A true JPH01215713A (en) 1989-08-29
JP2785263B2 JP2785263B2 (en) 1998-08-13

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Country Status (1)

Country Link
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01153525A (en) * 1987-12-11 1989-06-15 Tokin Corp Oxide superconductor of ag fine particle-containing oxygen deficient triple structure perovskite type and production thereof
JPH01164730A (en) * 1987-12-22 1989-06-28 Tanaka Kikinzoku Kogyo Kk Superconducting material and its production
JPH01192760A (en) * 1988-01-28 1989-08-02 Tokin Corp Ag2o3-containing oxide superconductor and production thereof
JPH01221810A (en) * 1987-10-23 1989-09-05 Furukawa Electric Co Ltd:The Oxide superconductive mold and its manufacture

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01221810A (en) * 1987-10-23 1989-09-05 Furukawa Electric Co Ltd:The Oxide superconductive mold and its manufacture
JPH01153525A (en) * 1987-12-11 1989-06-15 Tokin Corp Oxide superconductor of ag fine particle-containing oxygen deficient triple structure perovskite type and production thereof
JPH01164730A (en) * 1987-12-22 1989-06-28 Tanaka Kikinzoku Kogyo Kk Superconducting material and its production
JPH01192760A (en) * 1988-01-28 1989-08-02 Tokin Corp Ag2o3-containing oxide superconductor and production thereof

Also Published As

Publication number Publication date
JP2785263B2 (en) 1998-08-13

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