JPS63270319A - Production of ceramic superconductor - Google Patents
Production of ceramic superconductorInfo
- Publication number
- JPS63270319A JPS63270319A JP62106721A JP10672187A JPS63270319A JP S63270319 A JPS63270319 A JP S63270319A JP 62106721 A JP62106721 A JP 62106721A JP 10672187 A JP10672187 A JP 10672187A JP S63270319 A JPS63270319 A JP S63270319A
- Authority
- JP
- Japan
- Prior art keywords
- solution containing
- carbonate
- oxalate
- ceramic superconductor
- citrate
- 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
Links
- 239000002887 superconductor Substances 0.000 title claims abstract description 33
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 14
- 239000000919 ceramic Substances 0.000 title claims description 26
- 239000000203 mixture Substances 0.000 claims abstract description 16
- ZRALSGWEFCBTJO-UHFFFAOYSA-N Guanidine Chemical compound NC(N)=N ZRALSGWEFCBTJO-UHFFFAOYSA-N 0.000 claims abstract description 14
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052751 metal Inorganic materials 0.000 claims abstract description 14
- 239000002184 metal Substances 0.000 claims abstract description 14
- 150000003839 salts Chemical class 0.000 claims abstract description 13
- KRKNYBCHXYNGOX-UHFFFAOYSA-K Citrate Chemical compound [O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O KRKNYBCHXYNGOX-UHFFFAOYSA-K 0.000 claims abstract description 9
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 claims abstract description 9
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims abstract description 8
- 229940095064 tartrate Drugs 0.000 claims abstract description 8
- CHJJGSNFBQVOTG-UHFFFAOYSA-N N-methyl-guanidine Natural products CNC(N)=N CHJJGSNFBQVOTG-UHFFFAOYSA-N 0.000 claims abstract description 7
- SWSQBOPZIKWTGO-UHFFFAOYSA-N dimethylaminoamidine Natural products CN(C)C(N)=N SWSQBOPZIKWTGO-UHFFFAOYSA-N 0.000 claims abstract description 7
- ZBCBWPMODOFKDW-UHFFFAOYSA-N diethanolamine Chemical compound OCCNCCO ZBCBWPMODOFKDW-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052747 lanthanoid Inorganic materials 0.000 claims abstract description 3
- 150000002602 lanthanoids Chemical class 0.000 claims abstract description 3
- 229910052706 scandium Inorganic materials 0.000 claims abstract description 3
- 229910052727 yttrium Inorganic materials 0.000 claims abstract description 3
- 238000010304 firing Methods 0.000 claims description 13
- 239000000463 material Substances 0.000 abstract description 13
- 230000015572 biosynthetic process Effects 0.000 abstract description 8
- 238000002156 mixing Methods 0.000 abstract description 8
- 238000003786 synthesis reaction Methods 0.000 abstract description 8
- 239000000470 constituent Substances 0.000 abstract description 5
- 238000000975 co-precipitation Methods 0.000 abstract description 4
- 238000000034 method Methods 0.000 abstract description 4
- 239000010419 fine particle Substances 0.000 abstract description 2
- 150000002739 metals Chemical class 0.000 abstract 1
- 239000007864 aqueous solution Substances 0.000 description 20
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 9
- 239000000243 solution Substances 0.000 description 9
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 8
- 239000010949 copper Substances 0.000 description 8
- 239000000843 powder Substances 0.000 description 8
- 229910001960 metal nitrate Inorganic materials 0.000 description 7
- AYJRCSIUFZENHW-UHFFFAOYSA-L barium carbonate Chemical compound [Ba+2].[O-]C([O-])=O AYJRCSIUFZENHW-UHFFFAOYSA-L 0.000 description 6
- STIAPHVBRDNOAJ-UHFFFAOYSA-N carbamimidoylazanium;carbonate Chemical compound NC(N)=N.NC(N)=N.OC(O)=O STIAPHVBRDNOAJ-UHFFFAOYSA-N 0.000 description 6
- 229910000831 Steel Inorganic materials 0.000 description 5
- -1 aliphatic amine carbonates Chemical class 0.000 description 5
- 239000010959 steel Substances 0.000 description 5
- 229910052782 aluminium Inorganic materials 0.000 description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 239000001569 carbon dioxide Substances 0.000 description 4
- 229910002092 carbon dioxide Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000002244 precipitate Substances 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 3
- 229910052788 barium Inorganic materials 0.000 description 3
- HQABUPZFAYXKJW-UHFFFAOYSA-N butan-1-amine Chemical compound CCCCN HQABUPZFAYXKJW-UHFFFAOYSA-N 0.000 description 3
- 238000001354 calcination Methods 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229910003460 diamond Inorganic materials 0.000 description 3
- 239000010432 diamond Substances 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 150000003891 oxalate salts Chemical class 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 238000001308 synthesis method Methods 0.000 description 3
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 2
- AYJRCSIUFZENHW-DEQYMQKBSA-L barium(2+);oxomethanediolate Chemical compound [Ba+2].[O-][14C]([O-])=O AYJRCSIUFZENHW-DEQYMQKBSA-L 0.000 description 2
- RGSUDMCOVHKEHB-UHFFFAOYSA-N butan-1-amine;oxalic acid Chemical compound CCCCN.OC(=O)C(O)=O RGSUDMCOVHKEHB-UHFFFAOYSA-N 0.000 description 2
- MTBCJQLXXMMYTI-UHFFFAOYSA-N butylazanium;hydrogen carbonate Chemical compound OC([O-])=O.CCCC[NH3+] MTBCJQLXXMMYTI-UHFFFAOYSA-N 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- MRELNEQAGSRDBK-UHFFFAOYSA-N lanthanum(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[La+3].[La+3] MRELNEQAGSRDBK-UHFFFAOYSA-N 0.000 description 2
- 229910017604 nitric acid Inorganic materials 0.000 description 2
- 235000006408 oxalic acid Nutrition 0.000 description 2
- SIWVEOZUMHYXCS-UHFFFAOYSA-N oxo(oxoyttriooxy)yttrium Chemical compound O=[Y]O[Y]=O SIWVEOZUMHYXCS-UHFFFAOYSA-N 0.000 description 2
- 238000005204 segregation Methods 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 229910052712 strontium Inorganic materials 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 230000002194 synthesizing effect Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 239000005751 Copper oxide Substances 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 229910052581 Si3N4 Inorganic materials 0.000 description 1
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 1
- VFJSUHWDINTROM-UHFFFAOYSA-N [Ge].[Ge].[Ge].[Nb] Chemical compound [Ge].[Ge].[Ge].[Nb] VFJSUHWDINTROM-UHFFFAOYSA-N 0.000 description 1
- HFYPIIWISGZGRF-UHFFFAOYSA-N [Nb].[Sn].[Sn].[Sn] Chemical compound [Nb].[Sn].[Sn].[Sn] HFYPIIWISGZGRF-UHFFFAOYSA-N 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 229910052791 calcium Inorganic materials 0.000 description 1
- 239000011575 calcium Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 150000001860 citric acid derivatives Chemical class 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910000431 copper oxide Inorganic materials 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 150000002357 guanidines Chemical class 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- BDAGIHXWWSANSR-NJFSPNSNSA-N hydroxyformaldehyde Chemical compound O[14CH]=O BDAGIHXWWSANSR-NJFSPNSNSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000010955 niobium Substances 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- HYXGAEYDKFCVMU-UHFFFAOYSA-N scandium oxide Chemical compound O=[Sc]O[Sc]=O HYXGAEYDKFCVMU-UHFFFAOYSA-N 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 description 1
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 1
- 229910000018 strontium carbonate Inorganic materials 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 235000002906 tartaric acid Nutrition 0.000 description 1
- 239000011975 tartaric acid Substances 0.000 description 1
- 150000003892 tartrate salts Chemical class 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/01—Manufacture or treatment
- H10N60/0268—Manufacture or treatment of devices comprising copper oxide
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Superconductor Devices And Manufacturing Methods Thereof (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
本発明は、高温で電気抵抗がほとんどゼロになり高効率
電力貯蔵、強磁場発生、高効率送電等に利用できるセラ
ミックス超電導体の製造法に関する。DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a ceramic superconductor whose electrical resistance becomes almost zero at high temperatures and which can be used for highly efficient power storage, strong magnetic field generation, highly efficient power transmission, etc.
従来の技術
従来の超電導体としては、ニオブ３スズ（１８Ｋ）、ニ
オブ３ガリウム（２０Ｋ）、ニオブ３ゲルマニウム（２
４Ｋ）等の合金系があり、これら合金系超電導体のほと
んどが液体ヘリウムを必要とするものであった。しかし
、１９８６年４月ＩＢＭチューリッヒ研究所のに、Ａ、
ミュラーとＪ、Ｇ、ベドノルッ両博士によってＬａ
−Ｂａ−Ｃｕ−０系セラミツクスの高温における超電導
現象の示唆があって以来、種々検討され、Ｌａ−Ｂａ−
Ｃｕ−０系（３０Ｋ）、Ｌａ−８ｒ−Ｃｕ−０系（５４
Ｋ）、Ｙ−Ｂａ−Ｃｕ−０系（９８Ｋ）、Ｙ−Ｂａ−Ｃ
ｕ−０系（１２３Ｋ）、５ｃ−Ｂａ−Ｃｕ−０系（１７
５Ｋ）とセラミックス超電導体の臨界湿度はますます高
（なってきておリ、その応用研究も盛んに行われている
。Conventional technology Conventional superconductors include niobium tritin (18K), niobium trigallium (20K), and niobium trigermanium (20K).
4K), and most of these alloy-based superconductors require liquid helium. However, in April 1986, at the IBM Zurich Research Institute, A.
La by Dr. Muller and Dr. J.G.
-Since the suggestion of superconductivity in Ba-Cu-0 ceramics at high temperatures, various studies have been conducted, and La-Ba-
Cu-0 series (30K), La-8r-Cu-0 series (54
K), Y-Ba-Cu-0 system (98K), Y-Ba-C
u-0 series (123K), 5c-Ba-Cu-0 series (17
5K) and the critical humidity of ceramic superconductors is becoming higher and higher, and applied research is actively being carried out.
発明が解決しようとする問題点
セラミックス超電導体の製造法としては、一般的には酸
化物や炭酸塩を粉砕混合して焼成する方法が知られてい
る。この方法では、特にバリウムを含むセラミックス超
電導体材料の合成に際しては炭酸バリウムを分解するた
めに１０００℃付近、あるいは、それ以上の温度で焼成
合成する必要がある。しかるに、これらの材料系では１
０００℃付近でセラミックス超電導体材料に含まれる酸
化鋼が焼成時に使用するセラミックス基板やボートの成
分、即ち、アルミナ、シリカ、ジルコニア、窒化ケイ素
等、はとんどのセラミックスと反応するため得られた超
電導体材料中に含まれる銅の損失量が多く、また、その
偏析等も起こり、均一で超電導特性の安定したものを作
成するのが難しかった。また、セラミックス超電導体の
もう１つの製造法としてシュウ酸を用いた共沈法による
合成の報告がある。しかし、例えばマグネシウム、カル
シウム、ストロンチウム、バリウム等のＩＩａ族元素の
シュウ酸塩が酸に溶は易いため、一定の組成比で共沈さ
せることは極めて困難なものであった。Problems to be Solved by the Invention As a method for producing ceramic superconductors, a method is generally known in which oxides or carbonates are ground, mixed, and fired. In this method, especially when synthesizing a ceramic superconductor material containing barium, it is necessary to perform firing synthesis at a temperature of around 1000° C. or higher in order to decompose barium carbonate. However, in these material systems, 1
At around 000℃, the oxidized steel contained in the ceramic superconductor material reacts with the components of the ceramic substrate and boat used during firing, such as alumina, silica, zirconia, silicon nitride, etc., resulting in superconductivity. There was a large loss of copper contained in the body material, and its segregation also occurred, making it difficult to create a material with uniform superconducting properties. Furthermore, there is a report on synthesis by coprecipitation using oxalic acid as another method for producing ceramic superconductors. However, since oxalates of Group IIa elements such as magnesium, calcium, strontium, and barium are easily dissolved in acids, it has been extremely difficult to co-precipitate them at a constant composition ratio.
問題点を解決するための手段
本発明は、上記の問題点を解決するため、セラミックス
超電導体の構成金属の各成分を含む溶液にグアニジン系
の炭酸塩、シュウ酸塩、クエン酸塩、または酒石酸塩の
うち少なくとも一種の塩を含む溶液を混合しｐＨ５〜９
を終点として超電導体材料の各金属塩の共沈物を作成し
、また、脂肪族アミン炭酸塩、シュウ酸塩、クエン酸塩
、または酒石酸塩のうち少なくとも一種の塩を含む溶液
を用いる場合には、脂肪族アミン炭酸塩、シュウ酸塩、
クエン酸塩、または酒石酸塩のうち少なくとも一種の塩
を含む溶液に各金属成分を含む溶液を混合しｐＨ７〜９
を終点として超電導体材料の各金属塩の共沈物を作成、
焼成し超電導体材料を合成するものである。Means for Solving the Problems The present invention solves the above problems by adding guanidine carbonate, oxalate, citrate, or tartaric acid to a solution containing each constituent metal component of a ceramic superconductor. A solution containing at least one type of salt is mixed and the pH is adjusted to 5 to 9.
When a coprecipitate of each metal salt of the superconductor material is created as the end point, and a solution containing at least one salt of aliphatic amine carbonate, oxalate, citrate, or tartrate is used, are aliphatic amine carbonates, oxalates,
A solution containing each metal component is mixed with a solution containing at least one salt of citrate or tartrate, and the pH is 7 to 9.
Create a coprecipitate of each metal salt of the superconductor material with
It is used to synthesize superconductor materials by firing.
作用
本発明によるセラミックス超電導体の製造法により合成
した超電導体は、構成金属の各成分が、使用する有機塩
基物塩により炭酸塩、シュウ酸塩、クエン酸塩、あるい
は酒石酸塩と水酸化物の混合物として共沈されるため、
その粒子径は１μｍ以下の非常に微細なものになり、粒
子の混合に際しても均一に混合されるために、従来の合
成方法による金属酸化物や金属炭酸塩を使用して合成す
る方法に比べて合成に必要な焼成温度も低（、また、作
成された焼成体も極めて緻密な焼成体であり、超電導特
性が優れ、かつ安定した特性をもつセラミックス超電導
体が合成される。 特に、グアニジン系の塩では、グア
ニジン系有機物の水中での塩基度がＵａ族元素に比べて
強いためｐＨ５〜９を終点とすることで容易に仕込み組
成比と同様の組成比をもつ各金属塩の共沈物を得ること
ができ、また、脂肪族アミンの塩を用いた場合にでも、
脂肪族アミン塩を含む溶液に構成金属の各成分を含む溶
液を注ぎｐＨ７〜９を終点とすることで仕込み組成比と
ほぼ同様の組成比をもつ金属塩共沈物を得ることができ
、超電導特性が、再現性よく得られる。Function The superconductor synthesized by the method for producing a ceramic superconductor according to the present invention has a structure in which the constituent metal components are carbonate, oxalate, citrate, or tartrate and hydroxide, depending on the organic base salt used. Because it is coprecipitated as a mixture,
The particle size is very fine, less than 1 μm, and the particles are mixed evenly when mixed, compared to conventional synthesis methods using metal oxides and metal carbonates. The firing temperature required for synthesis is low (in addition, the created fired body is an extremely dense fired body, and a ceramic superconductor with excellent and stable superconducting properties is synthesized. In particular, guanidine-based Regarding salts, since the basicity of guanidine-based organic substances in water is stronger than that of Ua group elements, by setting the end point at pH 5 to 9, it is easy to create a coprecipitate of each metal salt with a composition ratio similar to the charged composition ratio. can be obtained, and even when using salts of aliphatic amines,
By pouring a solution containing each constituent metal component into a solution containing an aliphatic amine salt and setting the pH to 7 to 9 as the end point, it is possible to obtain a metal salt coprecipitate with a composition ratio that is almost the same as the charged composition ratio. characteristics can be obtained with good reproducibility.
実施例 以下、本発明の実施例について説明する。Example Examples of the present invention will be described below.
（実施例１）
Ｙ：Ｂａ：Ｃｕ＝１：２：３のモル比で各金属硝酸塩を
含む水溶液を撹拌し、ｐＨ計でｐＨＭを確認しながらグ
アニジン炭酸塩水溶液を添加した。沈殿物は、ｐＨ４以
上から確認されｐＨ５付近からグアニジン炭酸塩水溶液
を添加してもｐＨ値の変動の少ない領域が現れ、沈殿物
が生成する。その間ｐＨ値は７付近まで徐々に上昇する
。(Example 1) An aqueous solution containing each metal nitrate at a molar ratio of Y:Ba:Cu=1:2:3 was stirred, and a guanidine carbonate aqueous solution was added while checking the pHM with a pH meter. Precipitates are confirmed at a pH of 4 or above, and even when a guanidine carbonate aqueous solution is added from around pH 5, a region in which the pH value does not fluctuate appears, and a precipitate is formed. During this time, the pH value gradually increases to around 7.
ｐＨ７〜９付近までは急激に変動し、ｐＨ９より高い値
で再びｐＨの変動が少なくなり、この領域で鋼の溶出が
起こる。本実施例では、ｐ Ｈ８を終点としてグアニジ
ン炭酸塩の添加を止め、静置後、濾過し室温で予備乾燥
させた後、アルミナルツボに入れ空気中７００℃で仮焼
した。仮焼後、混合摺潰機で粉砕混合し、アルミナルツ
ボに入れ空気中９００℃で焼成し、セラミックス超電導
体粉末を得た。The pH fluctuates rapidly up to around 7 to 9, and the pH fluctuations decrease again at a value higher than 9, and elution of steel occurs in this region. In this example, the addition of guanidine carbonate was stopped at pH 8 as the end point, and after being allowed to stand, the mixture was filtered, pre-dried at room temperature, and then placed in an alumina crucible and calcined in air at 700°C. After calcining, the mixture was pulverized and mixed using a mixing grinder, placed in an aluminium crucible, and fired at 900°C in air to obtain ceramic superconductor powder.
このセラミックス超電導体粉末を硝酸水溶液に入れ二酸
化炭素の発生を調べたが二酸化炭素は発生しなかった。This ceramic superconductor powder was placed in a nitric acid aqueous solution to examine the generation of carbon dioxide, but no carbon dioxide was generated.
同一組成比で酸化イツトリウム。Yttrium oxide in the same composition ratio.
炭酸バリウム、酸化銅を混合拮潰機で充分に粉砕混合し
、前述と同様の操作を行い作成した。Barium carbonate and copper oxide were thoroughly pulverized and mixed using a mixing crusher, and the same operations as described above were performed to prepare the product.
従来の方法で作成した粉末では、多量の二酸化炭素が発
生し、炭酸バリウムが分解して反応していないことが認
められた。このため従来の合成法、即ち、酸化イツトリ
ウム、炭酸バリウム、酸化鋼を原料とする試料について
は１ｏｏｏ℃以上の温度で焼成し、粉砕混合した。It was observed that with the powder prepared using the conventional method, a large amount of carbon dioxide was generated and the barium carbonate decomposed and did not react. For this reason, samples using the conventional synthesis method, ie, samples made from yttrium oxide, barium carbonate, and oxidized steel, were fired at a temperature of 100° C. or higher, and pulverized and mixed.
本実施例による製造法と従来の合成法である酸化物と炭
酸塩で合成したセラミックス超電導体粉末を各々１ ’
、／ ｃ！以上で加圧成型し、空気中９゜０℃で焼成し
た後、ダイヤモンドカッターで２ ｎ＋ｎ角の棒状に切
り出して電気抵抗の温度特性を測定し、その結果を第１
図に示した。酸化物と炭酸塩で合成した場合、焼成温度
が偏析やルツボとの反応を起こす温度であるために特性
の高いものが得られにり（、また電流密度を高（した場
合、臨界温度付近で電気抵抗はゼロにならずテーリング
を起こした。これに対して、本実施例の製造法で合成し
た試料では電流密度を高くしても臨界温度付近で電気抵
抗はゼロであり特性の優れたものであった。Ceramic superconductor powders synthesized using oxides and carbonates using the production method according to this example and the conventional synthesis method were each
,/c! After the above pressure molding and firing in air at 9°0°C, the pieces were cut into 2n+n square rods using a diamond cutter and the temperature characteristics of electrical resistance were measured.
Shown in the figure. When synthesizing with oxides and carbonates, it is difficult to obtain products with high properties because the firing temperature is high enough to cause segregation and reaction with the crucible. The electrical resistance did not become zero and tailing occurred.On the other hand, in the sample synthesized using the production method of this example, the electrical resistance was zero near the critical temperature even when the current density was increased, indicating excellent characteristics. Met.
（実施例２）
ｎ−ブチルアミン２倍希釈の水溶液を氷で冷やして二酸
化炭素ガスを送りｎ−ブチルアミン炭酸塩を含む水溶液
を作成した。次に、共沈物の組成比をＹ：Ｂａ：Ｃｕ＝
１ ：２：３のモル比にするためにＢａとＣｕの量を多
くした各金ｍ６に酸塩を含む水溶液を作成した。ｎ−ブ
チルアミン炭酸塩を含む水溶液を撹拌し、ｐＨ計でｐ
Ｈ値を確認しながら各金属硝酸塩を含む水溶液を添加し
て共沈を行った。各金属硝酸塩を含む水溶液の添加はｐ
Ｈ７付近で止め撹拌を行いながら加温、あるい減圧処理
と希硝酸水溶液によるｐＨ値の調整を行い共沈物の組成
比がＹ：Ｂａ：Ｃｕ＝１：２：３になっていることを確
認して、濾過した。特に、Ｂａについてはｎ〜ブチルア
ミンに比べ塩基度が強いため徐々に溶出する傾向にあり
、また、一旦溶出したＢａは、Ｂａより塩基度の強いア
ルカリを添加しないと沈殿しない。(Example 2) An aqueous solution containing n-butylamine carbonate was prepared by cooling an aqueous solution of n-butylamine twice diluted with ice and supplying carbon dioxide gas. Next, the composition ratio of the coprecipitate is determined as Y:Ba:Cu=
An aqueous solution containing an acid salt of each gold m6 was prepared in which the amounts of Ba and Cu were increased to obtain a molar ratio of 1:2:3. Stir the aqueous solution containing n-butylamine carbonate and check the pH with a pH meter.
Co-precipitation was performed by adding an aqueous solution containing each metal nitrate while checking the H value. The addition of aqueous solutions containing each metal nitrate is p
The composition ratio of the coprecipitate was confirmed to be Y:Ba:Cu=1:2:3 by heating or reducing the pressure while stirring and adjusting the pH value with a dilute nitric acid aqueous solution at around H7. Checked and filtered. In particular, since Ba has a stronger basicity than n-butylamine, it tends to be gradually eluted, and once eluted, Ba does not precipitate unless an alkali having a stronger basicity than Ba is added.
合成のための焼成条件、電気抵抗測定試料の作成条件は
すべて実施例１と同様の条件で行った。The firing conditions for synthesis and the conditions for preparing samples for electrical resistance measurement were all the same as in Example 1.
この試料の電気抵抗の温度特性の結果を第２図に示した
。実施例１とほぼ同様の結果が得られ電流密度が高くて
も臨界温度付近で電気抵抗はゼロであり、酸化物と炭酸
塩合成物に比べ特性の優れたものであった。The results of the temperature characteristics of the electrical resistance of this sample are shown in FIG. Almost the same results as in Example 1 were obtained; even though the current density was high, the electrical resistance was zero near the critical temperature, and the properties were superior to those of oxide and carbonate composites.
（実施例３）
シュウ酸水溶液にｎ−ブチルアミンを加えｐＨ約１０の
ｎ−ブチルアミンシュウ酸塩を含む水溶液を作成した。(Example 3) n-Butylamine was added to an oxalic acid aqueous solution to create an aqueous solution containing n-butylamine oxalate having a pH of about 10.
次に、共沈物の組成比をＬａ５ｓｒ：ｃｕ＝１．２：０
．８： １のモル比にするためＳｒとＣｕの量を多くし
た各金属硝酸塩を含む水溶液を作成した。ｎ−ブチルア
ミンシュウ酸塩を含む水溶液を撹拌し、ｐＨ計でｐＨ値
を確認しながら各金属硝酸塩を含む水溶液を添加して共
沈を行った。各金属硝酸塩を含む水溶液の添加は、ｐＨ
８付近で止め、Ｌａ：Ｓｒ：Ｃｕ＝１．２：Ｏ，Ｓ：１
になっていることを確認して濾過した。室温で予備乾燥
させた後、アルミナルツボに入れ空気中５００℃で仮焼
した。仮焼後、混合描潰機で粉砕混合し、アルミナルツ
ボに入れて空気中８００℃で焼成し、セラミックス超電
導体粉末を作成した。この超電導体粉末を１）＝／ｃ−
以上で加圧成型し、空気中８００℃で焼成した後、ダイ
ヤモンドカッターで２＋ｎｍ角の棒状に切り出して電気
抵抗の温度特性を測定した。比較のために、酸化ランタ
ン、炭酸ストロンチウム、酸化鋼を出発原料としてセラ
ミックス超電導体を作成し電気抵抗の温度特性を測定し
た。合成は、空気中１０００℃で焼成し、電気抵抗測定
試料は、粉砕混合後、１１ツ／ ｃｄ以上で加圧成型し
８００℃で焼成して作成した。その結果、電気抵抗は、
４０に付近で急激に減少しゼロになった。しがし、酸化
物と炭酸塩で合成した試料では電流密度を高（した場合
、臨界温度付近で電気抵抗はゼロにならずテーリングを
起こした。これに対して、本実施例の製透性で合成した
試料では電流密度を高くしても臨界温度付近で電気抵抗
はゼロであり特性の優れたものであった。Next, the composition ratio of the coprecipitate was set as La5sr:cu=1.2:0
．． An aqueous solution containing each metal nitrate with increased amounts of Sr and Cu was prepared to achieve a molar ratio of 8:1. An aqueous solution containing n-butylamine oxalate was stirred, and while checking the pH value with a pH meter, an aqueous solution containing each metal nitrate was added to perform coprecipitation. The addition of an aqueous solution containing each metal nitrate will adjust the pH
Stop at around 8, La:Sr:Cu=1.2:O,S:1
After confirming that it was, it was filtered. After preliminary drying at room temperature, it was placed in an aluminum crucible and calcined in air at 500°C. After calcining, the mixture was pulverized and mixed using a mixer and crusher, placed in an aluminum crucible, and fired in air at 800°C to produce ceramic superconductor powder. This superconductor powder is 1)=/c-
After pressure molding and firing in air at 800° C., the product was cut into a 2+ nm square rod shape using a diamond cutter, and the temperature characteristics of electrical resistance were measured. For comparison, we created ceramic superconductors using lanthanum oxide, strontium carbonate, and oxidized steel as starting materials, and measured the temperature characteristics of their electrical resistance. Synthesis was performed by firing in air at 1000°C, and samples for electrical resistance measurement were prepared by pulverizing and mixing, molding under pressure at 11 T/cd or higher, and firing at 800°C. As a result, the electrical resistance is
Around 40, it suddenly decreased to zero. However, in the case of samples synthesized with oxides and carbonates, when the current density was high (at high current density), the electrical resistance did not become zero near the critical temperature and tailing occurred.In contrast, the permeability of this example The sample synthesized in 1 had excellent characteristics, with zero electrical resistance near the critical temperature even when the current density was increased.
（実施例４）
Ｓｃ：Ｂａ：Ｃｕ＝１ ：２：３のモル比で各金属硝酸
塩を含む水溶液を撹拌し、ｐＨ計でｐＨ値を確認しなが
らグアニジン炭酸塩水溶液を添加した。本実施例ではｐ
Ｈ８を終点としてグアニジン炭酸塩水溶液の添加を止め
、静置後、濾過し室温で予備乾燥させた後、アルミナル
ツボに入れ空気中７００℃で仮焼した。仮焼後、混合描
潰機で粉砕混合し、アルミナルツボに入れ空気中９００
℃で焼成してセラミックス超電導体粉末を得た。この超
電導体粉末を１ ’＞／ ｃｄ以上で加圧成型し、空気
中９００℃で焼成後、ダイヤモンドカッターで２ｍ角の
棒状に切り出し電気抵抗の温度特性を測定した。比較の
ために酸化スカンジウム、炭酸バリウム、酸化鋼を出発
原料としてセラミックス超電導体を作成し、電気抵抗の
温度特性を測定した。合成は、空気中１０００℃以上の
温度で焼成し、粉砕混合後、本実施例の製造法で合成し
たものと同様の操作で電気抵抗測定試料を作成した。(Example 4) An aqueous solution containing each metal nitrate at a molar ratio of Sc:Ba:Cu=1:2:3 was stirred, and a guanidine carbonate aqueous solution was added while checking the pH value with a pH meter. In this example, p
The addition of the guanidine carbonate aqueous solution was stopped at H8 as the end point, and after being allowed to stand, the mixture was filtered and preliminarily dried at room temperature, and then placed in an alumina crucible and calcined in air at 700°C. After calcining, it is crushed and mixed using a mixing and crushing machine, and then placed in an aluminum crucible and heated to 900% in the air.
Ceramic superconductor powder was obtained by firing at ℃. This superconductor powder was pressure-molded at 1'>/cd or higher, fired in air at 900°C, and then cut into 2m square rods using a diamond cutter to measure the temperature characteristics of electrical resistance. For comparison, ceramic superconductors were created using scandium oxide, barium carbonate, and oxidized steel as starting materials, and the temperature characteristics of electrical resistance were measured. The synthesis was performed by firing in air at a temperature of 1000° C. or higher, and after grinding and mixing, an electrical resistance measurement sample was prepared in the same manner as that synthesized by the manufacturing method of this example.
その結果、電気抵抗は、１００Ｋ付近で急激に減少しゼ
ロになった。しかし、酸化物と炭酸塩で合成した試料で
は電流密度を高くした場合、臨界温度付近で電気抵抗は
ゼロにならずテーリングをおこした。これに対して、本
実施例の製造法で合成した試料では電流密度を高くして
も臨界温度付近で電気抵抗はゼロであり特性の優れたも
のであった。As a result, the electrical resistance suddenly decreased to zero at around 100K. However, in samples synthesized from oxides and carbonates, when the current density was increased, the electrical resistance did not become zero near the critical temperature and tailing occurred. In contrast, the sample synthesized by the manufacturing method of this example had excellent characteristics, with zero electrical resistance near the critical temperature even when the current density was increased.
さらに、本実施例ではＡがＳｃ、Ｙ、Ｌａ、ＢがＳｒ、
Ｂａの場合のみを述べたがこれに限らず、Ａがランタノ
イド５８〜７１の元素の場合についても、また、ＢがＳ
ｒ、Ｂａ以外の■ａ族の元素の場合についても本実施例
と同様、酸化物と炭酸塩を用いた場合に比べ合成温度が
低くでき、しかも、均一で緻密なものができ特性の優れ
たものが得られる。ことは当然であり、本発明の範噴に
属するものである。Furthermore, in this example, A is Sc, Y, La, B is Sr,
Although only the case of Ba has been described, the case is not limited to this, but also the case where A is a lanthanoid element of 58 to 71, and the case where B is S
Similarly to this example, in the case of elements in the group ■a other than r and Ba, the synthesis temperature can be lower than when using oxides and carbonates, and moreover, a uniform and dense product can be produced with excellent properties. You can get something. Of course, this is within the scope of the present invention.
また、グアニジン塩のみ述べたが、グアニジンの水素を
他の有機物に置換した場合にも同様の効果を得ることは
当然であり、ｎ−ブチルアミンだけでなく、これと同程
度以上の塩基度をもつ脂肪族アミンでも同様の効果を得
ることができることは容易に推測されるものである。有
機塩基物塩として炭酸塩、シュウ酸塩のみ述べたが、ク
エン酸塩、酒石酸塩でも同様の効果を得ることができる
。In addition, although only guanidine salts have been described, it is natural that similar effects can be obtained when the hydrogen of guanidine is replaced with other organic substances. It is easily inferred that similar effects can be obtained with aliphatic amines. Although only carbonates and oxalates have been described as organic base salts, similar effects can be obtained with citrates and tartrates.
発明の効果
本発明は、グアニジン系、あるいは脂肪族アミンの炭酸
塩、シュウ酸塩、クエン酸塩、または酒石酸塩のうち少
なくとも一種の塩を含む溶液を用いてｐＨ値を調整して
セラミックス超電導体の構成金属の各成分を含む溶液と
混合し、共沈させることで微細な粒子を均一に混合する
ことができ、そのため従来に比べて低い温度で合成する
ことができ、しかも、均一で緻密な超電導特性の優れた
セラミックス超電導体を得ることができる。Effects of the Invention The present invention provides a ceramic superconductor by adjusting the pH value using a solution containing at least one of guanidine-based or aliphatic amine carbonate, oxalate, citrate, or tartrate. By mixing with a solution containing each constituent metal component and co-precipitating it, fine particles can be mixed uniformly. Therefore, it is possible to synthesize at a lower temperature than conventional methods, and it is possible to produce uniform and dense particles. A ceramic superconductor with excellent superconducting properties can be obtained.
第１図は本発明の一実施例の製造法で作成したセラミッ
クス超電導体の電気抵抗の温度特性図、第２図は本発明
の異なる実施例の製造法で作成したセラミクス超電導体
の電気抵抗の温度特性図である。Fig. 1 is a temperature characteristic diagram of the electrical resistance of a ceramic superconductor produced by a production method according to an embodiment of the present invention, and Fig. 2 is a diagram of the electrical resistance of a ceramic superconductor produced using a production method according to a different embodiment of the present invention. It is a temperature characteristic diagram.
Claims (2)
Ｓｃ、Ｙ、ランタノイド５７〜７１元素のうち少なくと
も一種の元素、ＢはIIａ族元素のうち少なくとも一種の
元素）の元素を含む溶液と、グアニジン系の炭酸塩、シ
ュウ酸塩、クエン酸塩、酒石酸塩のうち少なくとも一種
の塩を含む溶液とを混合してｐＨ５〜９を終点として金
属成分を共沈させ、焼成したことを特徴とするセラミッ
クス超電導体の製造法。(1) Composition ratio 0.5≦(A+B)/Cu≦2.5 (A is at least one element among Sc, Y, and 57 to 71 lanthanoid elements, B is at least one element among group IIa elements) A solution containing the element and a solution containing at least one kind of guanidine-based carbonate, oxalate, citrate, and tartrate are mixed, and the metal components are co-precipitated with a pH of 5 to 9 as the end point, followed by firing. A method for producing a ceramic superconductor characterized by the following.
、酒石酸塩のうち少なくとも一種の塩を含む溶液に、各
金属成分を含む溶液を入れ前記各金属成分をｐＨ７〜９
を終点として共沈させ、焼成したことを特徴とする特許
請求の範囲第１項記載のセラミックス超電導体の製造法
。(2) A solution containing each metal component is added to a solution containing at least one salt of an aliphatic amine carbonate, oxalate, citrate, and tartrate, and the pH of each metal component is adjusted to pH 7 to 9.
2. The method for producing a ceramic superconductor according to claim 1, wherein the ceramic superconductor is co-precipitated with a final point of .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62106721A JPH07106893B2 (en) | 1987-04-30 | 1987-04-30 | Manufacturing method of ceramics superconductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62106721A JPH07106893B2 (en) | 1987-04-30 | 1987-04-30 | Manufacturing method of ceramics superconductor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63270319A true JPS63270319A (en) | 1988-11-08 |
| JPH07106893B2 JPH07106893B2 (en) | 1995-11-15 |
Family
ID=14440815
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62106721A Expired - Fee Related JPH07106893B2 (en) | 1987-04-30 | 1987-04-30 | Manufacturing method of ceramics superconductor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07106893B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6437418A (en) * | 1987-07-31 | 1989-02-08 | Mitsubishi Metal Corp | Production of compound metal oxide |
| JPH01215711A (en) * | 1988-02-24 | 1989-08-29 | Oki Electric Ind Co Ltd | Formation of superconducting thick film |
| US5252314A (en) * | 1990-11-30 | 1993-10-12 | Case Western Reserve University | Method for producing coprecipitated multicomponent oxide powder precursors using guanidine oxalate as precipitating agent |
| CN114180942A (en) * | 2020-09-14 | 2022-03-15 | 日本碍子株式会社 | Composite sintered body, semiconductor manufacturing apparatus member, and method for manufacturing composite sintered body |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63252925A (en) * | 1987-04-10 | 1988-10-20 | Kazuo Fueki | Production of superconductive material |
-
1987
- 1987-04-30 JP JP62106721A patent/JPH07106893B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63252925A (en) * | 1987-04-10 | 1988-10-20 | Kazuo Fueki | Production of superconductive material |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6437418A (en) * | 1987-07-31 | 1989-02-08 | Mitsubishi Metal Corp | Production of compound metal oxide |
| JPH01215711A (en) * | 1988-02-24 | 1989-08-29 | Oki Electric Ind Co Ltd | Formation of superconducting thick film |
| US5252314A (en) * | 1990-11-30 | 1993-10-12 | Case Western Reserve University | Method for producing coprecipitated multicomponent oxide powder precursors using guanidine oxalate as precipitating agent |
| US5298654A (en) * | 1990-11-30 | 1994-03-29 | Case Western Reserve University | Method for producing coprecipitated multicomponent oxide powder precursors |
| CN114180942A (en) * | 2020-09-14 | 2022-03-15 | 日本碍子株式会社 | Composite sintered body, semiconductor manufacturing apparatus member, and method for manufacturing composite sintered body |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07106893B2 (en) | 1995-11-15 |
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