GB2232664A - Oxide materials - Google Patents
Oxide materials Download PDFInfo
- Publication number
- GB2232664A GB2232664A GB9012486A GB9012486A GB2232664A GB 2232664 A GB2232664 A GB 2232664A GB 9012486 A GB9012486 A GB 9012486A GB 9012486 A GB9012486 A GB 9012486A GB 2232664 A GB2232664 A GB 2232664A
- Authority
- GB
- United Kingdom
- Prior art keywords
- ceramic oxide
- oxides
- oxide
- temperature
- group
- 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.)
- Withdrawn
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- 239000000463 material Substances 0.000 title claims abstract description 32
- 239000000919 ceramic Substances 0.000 claims abstract description 21
- 229910052738 indium Inorganic materials 0.000 claims abstract description 7
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims abstract description 7
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052797 bismuth Inorganic materials 0.000 claims abstract description 6
- JCXGWMGPZLAOME-UHFFFAOYSA-N bismuth atom Chemical compound [Bi] JCXGWMGPZLAOME-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910052791 calcium Inorganic materials 0.000 claims abstract description 6
- 239000011575 calcium Substances 0.000 claims abstract description 6
- 229910052712 strontium Inorganic materials 0.000 claims abstract description 6
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 claims abstract description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052802 copper Inorganic materials 0.000 claims abstract description 5
- 239000010949 copper Substances 0.000 claims abstract description 5
- 230000007704 transition Effects 0.000 claims abstract description 5
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910052785 arsenic Inorganic materials 0.000 claims abstract description 4
- RQNWIZPPADIBDY-UHFFFAOYSA-N arsenic atom Chemical compound [As] RQNWIZPPADIBDY-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910052733 gallium Inorganic materials 0.000 claims abstract description 4
- 230000000737 periodic effect Effects 0.000 claims abstract description 4
- 229910003437 indium oxide Inorganic materials 0.000 claims abstract description 3
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(iii) oxide Chemical compound [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910052706 scandium Inorganic materials 0.000 claims abstract description 3
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000000203 mixture Substances 0.000 claims description 10
- 238000010304 firing Methods 0.000 claims description 5
- 238000002844 melting Methods 0.000 claims description 5
- 230000008018 melting Effects 0.000 claims description 5
- 238000009472 formulation Methods 0.000 claims description 4
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 238000000034 method Methods 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 239000002243 precursor Substances 0.000 claims description 2
- 239000008240 homogeneous mixture Substances 0.000 claims 2
- 238000004519 manufacturing process Methods 0.000 claims 1
- 239000008188 pellet Substances 0.000 description 10
- 239000012071 phase Substances 0.000 description 7
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 6
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 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 4
- 229910052787 antimony Inorganic materials 0.000 description 4
- WATWJIUSRGPENY-UHFFFAOYSA-N antimony atom Chemical compound [Sb] WATWJIUSRGPENY-UHFFFAOYSA-N 0.000 description 4
- 238000000634 powder X-ray diffraction Methods 0.000 description 4
- 238000007792 addition Methods 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- 238000005404 magnetometry Methods 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 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
-
- 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
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
A ceramic oxide material having a superconducting transition temperature (Tc) above 10K comprises a mixed oxide of bismuth, copper and one or more elements of Group 2 of the Periodic Table together with an addition of an oxide or oxides of one or more of indium, gallium, arsenic and scandium. Preferably, the one or more elements of Group 2 are strontium and calcium, and the addition is an indium oxide. A specific example is Bi1 &cirf& 5Pb0.4In0.1Sr2Ca2Cu3O9+x which is found to have a Tc of 65K. Within the above defined category of mixed ceramic oxides, the general formula Bi2-yInySr2CaCu2O8+x, where y is in the range 0.1 to 0.3 and x is a non-stoichiometric parameter, identifies a group of mixed ceramic oxides some of which have a Tc which is even higher still.
Description
Oxide Materials
This invention relates to ceramic oxide materials having a superconducting transition temperature above 10K.
Since early 1986, certain families of ceramic oxide materials have been found to be superconductive at temperatures above the highest superconducting transition temperatures (Tc) known for metal alloys. One such family comprises material formulations based on ABxCuyOz and derivatives, where A is a metal in the oxidation state III and B is a metal in the oxidation state II. In an example of a member of such a family, A is bismuth and B is one or more elements of#Group 2 of the Periodic Table such as strontium and calcium. Moreover, it is known that such a member may be doped with lead and it is further known that further doping with small amounts of antimony can enhance the superconducting properties of such material. See Sol.
St. Comms., 69 (8), 867, 1989 which describes the material Bil.9#xPbxSb0.lSr2Ca2 Cu3Oz.
It has now been found that use of additions of one or more of indium, gallium and possibly arsenic in place of all or part of the lead or antimony or both in the above-mentioned known material can enhance the Tc of the material when compared with otherwise similar material containing antimony or lead or both.
Thus, in one aspect the invention provides a ceramic oxide material having a superconducting transition temperature above 10K comprising a mixed oxide of bismuth, copper and one or more elements of Group 2 of the Periodic
Table together with an addition of an oxide or oxides of one or more of indium, gallium, arsenic and scandium.
Preferably, the one or more elements of Group 2 are strontium and calcium, and the addition is an indium oxide.
An example of a material of the invention is Bi1 5Pb0 41n0 lSr2Ca2Cu3O9+x.
It has been found that the above exemplified material, when made in the way exemplified hereinafter, has a Tc of 65K which is superior to that of the corresponding material, made in an equivalent way and also exemplified hereinafter, where antimony is substituted for indium and which has been found to have a Tc of 30K.
The formulae used herein may be empirical in the sense that they do not necessarily represent phases that are present in the material. For example, an X-ray powder diffraction pattern of the above example of a material of the invention detected the phases Bi2Sr2Ca2Cu3O9+x and Ca2PbO4.
Also, the subscripts x, y and z in the formulae herein cannot be precisely defined: they are used as an indication only, e.g. that there is a deficiency or surfeit of the element to which they are appended. Further, each formula is to be regarded as self-contained, e.g. x in one formula does not necessarily relate to x in another formula.
A group of mixed ceramic oxides falling within the general definition given above has now been identified, which group has the general formula Ri2-yInySr2CaCu208+xr where y is in the range from 0.1 to 0.3 and x is a non-stoichiometric parameter. Specific formulations falling within the above general formula have been found, in certain cases, to have
Tc's of greater than 70K. A particular noteworthy such specific formulation is Bil.91n0.lSr2CaCu2O8+x, the electrical resistance value of which as a function of temperature are given hereinafter.
The materials of the invention are conveniently made, constituting a second aspect of the invention, by mixing oxides, or precursors of oxides, of the metals of the intended material in stoichiometric proportions to form a homogelleous mixture, and firing the mixture, for example at about 7500K to give the material. Conditions of firing are generally found to influence the superconducting properties of the material. In particular, we have found that formation of the desired superconducting phase is enhanced by firing at a temperature which is raised as high as it can be without any melting within the mixture. If the firing temperature is reduced below this level, there is formation of another phase, the Tc of which is very much lower than that of the desired superconducting phase.
The ceramic oxide materials can be made as artefacts or fabricated into artefacts so that they can be used as or in electrical devices.
The invention will now be particularly described, by way of example only, as follows where reference will be made to the accompanying drawing, the sole figure of which is a graph showing the relationship between electrical resistance and temperature for a mixed ceramic oxide of the invention:
EXAMPLE 1
Preparation of Material Oxides of bismuth, lead, indium, strontium, calcium and copper, each of not less than 99% purity, and in relative proportions corresponding to the formula Bil.5Pb0.41n0.lSr2Ca2Cu3O9+x were wet milled or wet ball milled using hexane or acetone as the liquid phase and alumina balls. The liquid was then allowed to evaporate to leave a dry mixture which was then ground mechanically and pressed into cylindrical pellets (ca. llmm diameter and 3mm thick).The pellets were fired in alumina crucibles in air at a temperature held as high as practicable without melting as judged by X-ray powder diffraction (about 7500C).
Properties of Material
(i) Structure
X-ray powder diffraction using a Siemens D500 diffractometer and Cuki radiation showed the phases Bi2Sr2Ca2Cu3O9+x and Ca2PbO4 to be present in the above material.
(ii) Electrical Resistance
The above prepared pellet was lowered into a fixed temperature cryostat using a specially designed probe and its resistance as a function of temperature measured using a standard four point contact technique; a constant current was passed through two outer points and voltage drop measured across the inner two via a Keithly meter linked to a microcomputer that also measured temperature in real time via a thermocouple adjacent the pellet. A zero resistance condition (Tc) was identified at 65K.
(iii) Magnetic Susceptibility Measurements
A coil was wound around a ferrite core and the above prepared pellet pressed up against it from above at the end of a probe and lowered into a fixed temperature cryostat.
The magnetic susceptibility of the pellet was measured as a function of temperature using a Hewlett-Packard AC meter normally operated at 10KHz Tc, identified by a steep drop in inductance, was again found to be 65K.
COMPARATIVE EXPERIMENT
The precedure of the above example was repeated for the known material Bi1 5Pb0 4Sb0 lSr2Ca2Cu3O9+x.
Tc was found to be 30K using both resistance and magnetic susceptibility measurements.
EXAMPLE II
Preparation of Mixed Ceramic Oxide
Oxides of bismuth, indium, strontium, calcium and copper, each of not less than 99% purity and in relative proportions corresponding to the formula Bi1.91n0.lSr2CaCu2O9 were wet milled or wet ball milled using hexane or acetone as the liquid phase and alumina balls. The liquid was then allowed to evaporate to leave a dry mixture which was then ground mechanically and pressed into cylindrical pellets (ca. 11 mm diameter and 3 mm thick). The pellets were fired in alumina crucibles in air at a temperature sufficient to cause reaction and held as high as practicable without melting as judged by X-ray powder diffraction (about 7500C).
Electrical Resistance Properties of Mixed Ceramic
Oxide
The above prepared pellet was lowered into a fixed temperature cryostat using a probe and its resistance as a function of temperature measured using a standard four point contact technique; a constant current was passed through two outer points and voltage drop measured across the inner two via a Keithly meter linked to a microcomputer that also measured temperature in real time via a thermocouple adjacent the pellet.
The results are shown in the sole figure of the accompanying drawings which indicate stepped decreases in resistance at 75,80 and 150K corresponding to different components of the phase mixture.
Claims (9)
1. A ceramic oxide material having a superconducting transition temperature above 10K comprising a mixed oxide of bismuth, copper and one or more elements of Group 2 of the Periodic Table together with an addition of an oxide or oxides of one or more of indium, gallium, arsenic and scandium.
2. A ceramic oxide material as claimed in claim 1, wherein the said one or more elements of Group 2 comprise one or both of strontium and calcium.
3. A ceramic oxide as claimed in claim 1 or claim 2, wherein the said addition is an indium oxide.
4. A ceramic oxide as claimed in claim 3, having the formula Bil.SPb0.41n0.lSr2Ca2Cu3O9+x and fabricated to provide superconductivity at a temperature of 65K or less.
5. A ceramic oxide material as claimed in claim 1, characterised by the general formula Bi2#yInySr2CaCu2O8+x, where y is in the range 0.1 to 0.3 and x is a non-stoichiometric parameter.
6. A ceramic oxide as claimed in claim 5, having the formula Bil.91n0.lSr2CaCu2O8+x.
7. A method of manufacturing a ceramic oxide material as claimed in any of claims 1 to 6, which method comprises mixing oxides, or precursors of oxides of the metals of the intended mixed ceramic oxide formulation in stoichiometric proportions to form a homogeneous mixture, and firing at a temperature for causing inter-reaction to form ceramic oxide material.
8. A method as claimed in claim 7, wherein the said homogeneous mixture is fired at a temperature at which there is no melting but which is as close as practicable to that at which melting occurs.
9. A ceramic oxide material made according to Example I or Example II as herein described.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB898913979A GB8913979D0 (en) | 1989-06-17 | 1989-06-17 | Oxide materials |
| GB909000251A GB9000251D0 (en) | 1990-01-05 | 1990-01-05 | Oxide materials |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9012486D0 GB9012486D0 (en) | 1990-07-25 |
| GB2232664A true GB2232664A (en) | 1990-12-19 |
Family
ID=26295503
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9012486A Withdrawn GB2232664A (en) | 1989-06-17 | 1990-06-05 | Oxide materials |
Country Status (2)
| Country | Link |
|---|---|
| GB (1) | GB2232664A (en) |
| IT (1) | IT9067442A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2249786A (en) * | 1990-11-01 | 1992-05-20 | Atomic Energy Authority Uk | Superconducting oxide materials |
| US5208214A (en) * | 1988-12-29 | 1993-05-04 | Hoechst Aktiengesellschaft | Multiphase superconductor and process for its production |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0323190A2 (en) * | 1987-12-28 | 1989-07-05 | Canon Kabushiki Kaisha | Superconductive metal oxide material |
| WO1989007087A1 (en) * | 1988-02-04 | 1989-08-10 | E.I. Du Pont De Nemours And Company | SUPERCONDUCTING Bi-Sr-Ca-Cu OXIDE COMPOSITONS AND PROCESS FOR MANUFACTURE |
| EP0344406A2 (en) * | 1988-06-01 | 1989-12-06 | The Agency of Industrial Science and Technology | Tl-based copper oxide superconductor |
-
1990
- 1990-06-05 GB GB9012486A patent/GB2232664A/en not_active Withdrawn
- 1990-06-15 IT IT067442A patent/IT9067442A1/en unknown
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0323190A2 (en) * | 1987-12-28 | 1989-07-05 | Canon Kabushiki Kaisha | Superconductive metal oxide material |
| WO1989007087A1 (en) * | 1988-02-04 | 1989-08-10 | E.I. Du Pont De Nemours And Company | SUPERCONDUCTING Bi-Sr-Ca-Cu OXIDE COMPOSITONS AND PROCESS FOR MANUFACTURE |
| EP0344406A2 (en) * | 1988-06-01 | 1989-12-06 | The Agency of Industrial Science and Technology | Tl-based copper oxide superconductor |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5208214A (en) * | 1988-12-29 | 1993-05-04 | Hoechst Aktiengesellschaft | Multiphase superconductor and process for its production |
| GB2249786A (en) * | 1990-11-01 | 1992-05-20 | Atomic Energy Authority Uk | Superconducting oxide materials |
Also Published As
| Publication number | Publication date |
|---|---|
| IT9067442A0 (en) | 1990-06-15 |
| IT9067442A1 (en) | 1990-12-18 |
| GB9012486D0 (en) | 1990-07-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |