CN1016299B - 高温超导体 - Google Patents
高温超导体Info
- Publication number
- CN1016299B CN1016299B CN89101490A CN89101490A CN1016299B CN 1016299 B CN1016299 B CN 1016299B CN 89101490 A CN89101490 A CN 89101490A CN 89101490 A CN89101490 A CN 89101490A CN 1016299 B CN1016299 B CN 1016299B
- Authority
- CN
- China
- Prior art keywords
- superconductor
- hours
- strontium
- calcium
- bismuth
- 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.)
- Expired
Links
- 239000002887 superconductor Substances 0.000 title claims abstract description 20
- 239000000463 material Substances 0.000 claims description 31
- 238000005245 sintering Methods 0.000 claims description 20
- 239000011575 calcium Substances 0.000 claims description 13
- 230000007704 transition Effects 0.000 claims description 13
- 239000010949 copper Substances 0.000 claims description 12
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims description 11
- 238000006243 chemical reaction Methods 0.000 claims description 11
- 229910052797 bismuth Inorganic materials 0.000 claims description 10
- 229910052712 strontium Inorganic materials 0.000 claims description 9
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 claims description 9
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 8
- 229910052791 calcium Inorganic materials 0.000 claims description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 7
- 229910052802 copper Inorganic materials 0.000 claims description 6
- 238000000227 grinding Methods 0.000 claims description 6
- 238000000034 method Methods 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 4
- 239000012535 impurity Substances 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 3
- VVTSZOCINPYFDP-UHFFFAOYSA-N [O].[Ar] Chemical compound [O].[Ar] VVTSZOCINPYFDP-UHFFFAOYSA-N 0.000 claims description 2
- 229910001882 dioxygen Inorganic materials 0.000 claims description 2
- VAWSWDPVUFTPQO-UHFFFAOYSA-N calcium strontium Chemical compound [Ca].[Sr] VAWSWDPVUFTPQO-UHFFFAOYSA-N 0.000 claims 1
- 238000002360 preparation method Methods 0.000 claims 1
- QPLDLSVMHZLSFG-UHFFFAOYSA-N CuO Inorganic materials [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 5
- IATRAKWUXMZMIY-UHFFFAOYSA-N strontium oxide Chemical compound [O-2].[Sr+2] IATRAKWUXMZMIY-UHFFFAOYSA-N 0.000 description 5
- 238000011160 research Methods 0.000 description 4
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 3
- 239000000292 calcium oxide Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 2
- 229910000416 bismuth oxide Inorganic materials 0.000 description 2
- 229960004643 cupric oxide Drugs 0.000 description 2
- TYIXMATWDRGMPF-UHFFFAOYSA-N dibismuth;oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Bi+3].[Bi+3] TYIXMATWDRGMPF-UHFFFAOYSA-N 0.000 description 2
- 229910016300 BiOx Inorganic materials 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 229910016553 CuOx Inorganic materials 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000013213 extrapolation Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/45—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on copper oxide or solid solutions thereof with other oxides
- C04B35/4521—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on copper oxide or solid solutions thereof with other oxides containing bismuth oxide
- C04B35/4525—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on copper oxide or solid solutions thereof with other oxides containing bismuth oxide also containing lead oxide
-
- 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
-
- 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
- H10N60/80—Constructional details
- H10N60/85—Superconducting active materials
- H10N60/855—Ceramic superconductors
- H10N60/857—Ceramic superconductors comprising copper oxide
-
- 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
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S505/00—Superconductor technology: apparatus, material, process
- Y10S505/775—High tc, above 30 k, superconducting material
- Y10S505/776—Containing transition metal oxide with rare earth or alkaline earth
- Y10S505/782—Bismuth-, e.g. BiCaSrCuO
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Ladders (AREA)
Abstract
Bi(pb)Sr(ca)-CuOx系超导材料,具有5或8.7倍钙钛矿晶胞超结构的相。
Description
本发明涉及Bi-Sr(Ca)-CuOx系高温超导体。
Bednorz和Müller已公开了镧-锶-铜氧化物系超导体,这类超导体具有以前从未达到过的由普通导体跃迁为超导体的高转变温度。钇-钡-铜氧化物所达到的转变温度为70至90K。最近公开的另一系超导体,即铋-锶-钙-铜氧化物业已进行了深入的研究,所研究的问题涉及烧结过程中,诸如烧结温度、烧结时间和氧气分压力等烧结参数的影响。
上述第二种材料的制造是采用粉末原料,经混合、碾磨和冷压后,置于氧化锆板上,在微处理机控制的炉中进行烧结。在空气中进行烧结的烧结温度为800,860,880,900℃,烧结时间长达10小时。将金属与试样接触,测量其电特性;通过测量材料周围线圈的感应率测定各种材料的磁性。
本发明的任务在于提供超过90K或等于105K的高转变温度的高温超导材料的化学组分。
本发明的任务的材料是通过下列组分解决的,即:
其中,0.01<x<0.5,
0≤y<x<0.5,
0≤d,
0≤u,
d约等于2y或u,u为0.1至0.3,或u=0.2±10%。该种材料除杂质
外,不含有铅,晶胞结构中基本上不含有铋。
本发明的基础是:
测量规定组分的分子式为BiSrCaCu2Ox系的超导材料试样中电阻和电感的急速下降;测量零电阻与55至175K温度的相关性。零电阻与温度的相关曲线给出在空气中和在860°至880℃温度下经过长达10小时烧结的材料的电阻降低的两个阶段。采用相应的线性外推法得到超导相变的温度值为100至105K。
这项结果被认为很容易重复,而且经过较长时间烧结的试样也很容易冲压。在900℃和900℃以上烧结温度的试样上,观测到半导体性能。
在本发明范围内所进行的广泛研究,其目的在于从所研究的具有二相或多相结构的材料中,能够研制出一种其结构可得到转变温度为100至105K的超导材料。
本发明的另一基础在于上述材料是多相的,而且两种超导材料共存,其中之一具有上述的高转变温度。
本发明人成功地发现,具有大约105K转变温度的这种材料至少主要是由铋-锶-钙-铜氧化物系的相,尤其是由铅部分取代铋的材料组成的。从《科学》(Science,239卷,1988年2月,1015-1016页,尤其是图3)已知,含有规定组分氧化铋-锶-钙-氧化铜系的超导材料具有层状结构,其氧化铋层与由氧化锶-氧化铜-氧化钙(锶)-氧化铜-氧化锶组成的层序可以互相置换。
在导致本发明的研究中确认,晶格常数a=0.54nm和C=3nm(由电子显微镜衍射测定)的相,即与由上述出版物公开的相一样,具有80K的转变温度。但是还确认了存在另一个相,其晶格常数a也等于0.54nm,而晶格常数C=3.6nm,更精确地说为3.7~3.8nm。更深入的研究还进一步了解到,这个相除了技术上具有特殊优点的超导特性之外,还具有105K
的更高的转变温度。
这种超导材料具有至今所分析的A-面心正交对称的正交晶格。在<010>轴中的电子显微镜衍射图能分辨出A-面心正交晶格和F-面心正交晶格。
还确定a=0.54nm和C=3.6nm或3.7至3.8nm的本发明的基本结构在于其平行于<010>或<100>方向上具有5倍或8.7倍超结构。本发明材料的晶胞具有由氧化锶,(氧化钙)和氧化铜组成的BiOx双层和钙钛矿晶胞的结构。这些晶胞也可含有铋和/或铅,即除了含铋外也可含铅。本发明材料具有夹三层式的结构,其由氧化铋或(Bi1-uPbu)氧化物组成的层状和由呈层状的钙钛矿晶胞组成的层次可以互换。本发明这种结构的层序如下:
(铋1-u铅u)/锶(钙)/铜/钙(锶)/铜/钙(锶)/铜/锶(钙/(铋1-u铅u),其晶格常数如上所述,即C=3.6nm。括号中的元素可以部分取代括号前的元素。
本发明的超导材料具有下列化学计量组分:
其中,0.01<X<0.5
0≤y<x<0.5
0≤d≌2y或≌U
0≤u,
其转变温度高于90K。
如所测定的那样,这种材料的转变温度可达到105至120K。
即使本发明材料不能完全达到所给出的105至110K高转变温度,本发明的材料与有关与之竟争的超导材料相比,仍然具有很大的技术优点,因为本发明的材料与大气反应不那么快,即对大气具有较高的抗性。
采用其他方法也可制造本发明的材料。相应于上述组分在上述x,y,d和u的极限值范围内,选择相应的原料(氧化物,碳酸盐等)。在各个相继的制造步骤中视其产生的损耗量(研磨、过筛、反应和烧结时的损耗)考虑相应增加原料量。
将称取的物料相互混合和研磨,尤其可在研磨时进行混合,并且可用一般的球磨机进行研磨。研磨后的原料按常规方法,在普通的高温(700℃至1000℃,尤其在800℃至820℃下)进行反应(转化为氧化物)。在再次进行研磨后对样品进行压制和烧结。烧结温度为800℃至1000℃,优先采用880°±20℃,尤以860°至865℃为佳。烧结时间为10小时,尤以60至120小时为佳。反应优先在空气中进行。这种制造方法能够制取超导材料,即通过成型和压制得到预定尺寸的超导体。此外,这种料料也可采用常规加工过程进行制造。
本发明的一个实施例如下:
按已确定的Bi1.7Pb0.4Sr1.7Ca2.1Cu3重量,称重Bi2O3,PbO,SrCO3,CaO和CuO。反应在空气中进行,先在800℃反应3小时,再在820℃反应10至20小时,同时进行间隔研磨。反应后经再次研磨和压制后,在860°至865℃温度下和在空气中烧结60至120小时。在Po2=1/13巴条件下和在氩氧混合气体中,烧结60至120小时,烧结温度为843℃,同样能获得良好的效果,制得含铅量u=0.2±10%的材料。
附图给出本发明材料的结构层序的截面图,C轴呈垂直方向。
P表示3层钙钛矿晶胞。
Claims (7)
1、Bi-Sr(Ca)-CuOx系超导材料,其特征在于原料组分为:
其中,0.01<x<0.5,
O≤y<x<0.5,
0≤d,优先约等于2y或u,
0≤u,
转变温度高于90K。
2、按权利要求1的超导材料,该材料具有由铋(铅)、锶(钙)、和铜的氧化物组成层状结构,其特征在于所述氧化物的层序为铋(铅)、锶(钙)、铜、钙(锶)、铜、钙(锶)、铜、锶(钙)、铋(铅),其中括号中的元素可分别部分代替其前面所述的元素。
3、按权利要求1或2的超导材料,其特征在于除杂质外不含有铅。
4、按权利要求1或2的超导材料,其特征在于除了杂质外,晶胞结构基本上不含铋。
5、按权利要求1的超导材料,其特征在于u在0.1和0.3之间。
6、按权利要求5的超导材料,其特征在于u=0.2±10%。
7、制备权利要求6的超导材料的方法,其特征在于:
(A)重量为Bi1.7Pb0.4Sr1.7Ca2.1Cu3的材料在空气中随着间隔研磨,先于800℃反应3小时,再于820℃反应10至20小时,将经过反应的材料进行研磨压制,在空气中和860℃至865℃温度下烧结60至120小时;或
(b)重量为Bi1.7Pb0.4Sr1.7Ca2.1Cu3的材料在空气中随着间隔研磨,先于800℃反应3小时,再于820℃反应10至20小时,将经过反应的材料进行研磨压制,在Po2=1/13巴的氩氧混合气体中和大约843℃温度下烧结60至120小时。
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE3808447A DE3808447C2 (de) | 1988-03-14 | 1988-03-14 | Hochtemperatur-Supraleiter des Systems Bi-Sr (Ca)-CuO¶x¶ |
DEP3808447.3 | 1988-03-14 |
Publications (2)
Publication Number | Publication Date |
---|---|
CN1036100A CN1036100A (zh) | 1989-10-04 |
CN1016299B true CN1016299B (zh) | 1992-04-15 |
Family
ID=6349684
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN89101490A Expired CN1016299B (zh) | 1988-03-14 | 1989-03-14 | 高温超导体 |
Country Status (7)
Country | Link |
---|---|
US (1) | US5665662A (zh) |
EP (1) | EP0404790B2 (zh) |
JP (1) | JPH02504261A (zh) |
CN (1) | CN1016299B (zh) |
AT (1) | ATE126397T1 (zh) |
DE (2) | DE3808447C2 (zh) |
WO (1) | WO1989008929A1 (zh) |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NZ228132A (en) | 1988-04-08 | 1992-04-28 | Nz Government | Metal oxide material comprising various mixtures of bi, tl, pb, sr, ca, cu, y and ag |
JPH01320227A (ja) * | 1988-06-20 | 1989-12-26 | Daikin Ind Ltd | ビスマス系酸化物超電導材料の製造方法 |
EP0377359B1 (en) * | 1988-12-05 | 1994-04-20 | Sumitomo Electric Industries, Ltd. | Oxide superconducting material, process for preparing the same and applications thereof |
US5264413A (en) * | 1990-03-07 | 1993-11-23 | Ivan Bozovic | Bi-Sr-Ca-Cu-O compounds and methods |
KR20060055444A (ko) * | 2003-09-17 | 2006-05-23 | 스미토모 덴키 고교 가부시키가이샤 | 초전도 기기 및 초전도 케이블 |
US8723372B2 (en) | 2010-10-20 | 2014-05-13 | Larry A. Park | System for inducing a high efficiency conductive state in materials |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0327044B2 (de) * | 1988-02-05 | 1998-04-22 | Hoechst Aktiengesellschaft | Supraleiter und Verfahren zu seiner Herstellung |
US4880771A (en) * | 1988-02-12 | 1989-11-14 | American Telephone And Telegraph Company, At&T Bell Laboratories | Bismuth-lead-strontium-calcium-cuprate superconductors |
-
1988
- 1988-03-14 DE DE3808447A patent/DE3808447C2/de not_active Expired - Fee Related
-
1989
- 1989-03-10 DE DE58909382T patent/DE58909382D1/de not_active Expired - Lifetime
- 1989-03-10 EP EP89903100A patent/EP0404790B2/de not_active Expired - Lifetime
- 1989-03-10 WO PCT/DE1989/000154 patent/WO1989008929A1/de active IP Right Grant
- 1989-03-10 AT AT89903100T patent/ATE126397T1/de not_active IP Right Cessation
- 1989-03-10 JP JP1502836A patent/JPH02504261A/ja active Granted
- 1989-03-10 US US07/576,408 patent/US5665662A/en not_active Expired - Lifetime
- 1989-03-14 CN CN89101490A patent/CN1016299B/zh not_active Expired
Also Published As
Publication number | Publication date |
---|---|
WO1989008929A1 (en) | 1989-09-21 |
US5665662A (en) | 1997-09-09 |
JPH0583489B2 (zh) | 1993-11-26 |
EP0404790B2 (de) | 2007-10-17 |
DE3808447C2 (de) | 1995-09-28 |
DE58909382D1 (de) | 1995-09-14 |
DE3808447A1 (de) | 1989-09-28 |
EP0404790A1 (de) | 1991-01-02 |
CN1036100A (zh) | 1989-10-04 |
ATE126397T1 (de) | 1995-08-15 |
JPH02504261A (ja) | 1990-12-06 |
EP0404790B1 (de) | 1995-08-09 |
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