WO2001041227A1

WO2001041227A1 - High temperature superconductor composite material and method of producing a product from the material

Info

Publication number: WO2001041227A1
Application number: PCT/US1999/028917
Authority: WO
Inventors: M. I. Topchiashvili; A. E. Rokhvarger
Original assignee: Topchiashvili M I; Rokhvarger A E
Priority date: 1999-12-06
Filing date: 1999-12-06
Publication date: 2001-06-07

Abstract

A high temperature superconductor composite material capable of working at liquid nitrogen and higher temperatures K > 77, comprising a sintered compound of high temperature superconductor ceramics; a silver dope; silicone residuals in form of silica and silicon; and sintering products of interaction of said sintered compound and said silver dope with silicone material. The composite material is expecially workable and allows forming any useful element and article, such as continuous wire and tape, a coil, a chip, a screen, a short bulk-shaped structure and a long-length bulk-shaped structure, such as a rod, a beam, a tube, and a rail. The composite material has significantly increased electrical-magnetic properties, strain tolerance, ductility and durability in working ambience.

Description

High Temperature Superconductor Composite Material and Method of Producing a Product from the Material

Technical Field

The present invention deals with a high temperature superconductor composite material and a method of producing the same.

Background Art

The discovered in the end of 1980^th high temperature superconductor (HTS) ceramics are very chemically active, brittle and degrade under environmental and magnetic field influences. Until now it was unknown how to avoid these disadvantages for practical use of the HTS ceramics. For example, it was unknown formulations of the HTS ceramics to make continuous and quality assured HTS wires and coils, simple and difficulty shaped films and variously shaped products from these very fragile ceramics to produce practical and inexpensive electrical energy and electronics applications. It is believed to be clear that it is very important to develop a high temperature superconductor ceramic composite material with high workability of the raw material composition, which makes possible a cost-effective producing all necessary product nomenclature for electrical and electronics industries, avoiding disadvantages of the prior art.

The present invention relates to an innovative high temperature superconductor composite material with significantly improved and increased electrical-magnetic and structural properties, such as strain tolerance and ductility, which cause practically acceptable reliability and durability on the air and in working conditions at temperatures more 77K. Invented material formulation includes especially workable raw material composition, which allows to make a suspension of fine powder particles of high temperature superconductor ceramics and silver dope in silicone rubber or silicone lacquer emulsion in toluene or acetone. An application of the workable and homogeneous suspension causes a several advantages adjusting and creatively combining advanced forming and thermal treatment methods and physical impacts on the composite material. The invention determines chemical composition of raw materials, associated chemical ingredients, additives, aids and susceptors to the HTS ceramics to accommodate invented HTS composite material formulation and forming methods for all potential needs of the electrical and electronic industries.

Disclosure of the Invention

Accordingly, it is an object of the present invention to provide a new high temperature superconductor (HTS) ceramic composite material, avoiding the disadvantages of the prior art. It is invented workable raw material composition and a workable material formulation of producing superior HTS products.

It is also another object of the present invention to provide a new method for producing the new high temperature superconductor of the present invention.

In keeping with these objects and with others, which will become apparent hereinafter, one key feature of present invention resides, briefly stated in a high temperature superconductor composite material which comprises a sintered compound of a superconductor ceramics, sintering residuals and their products of the silicone material selected from the group consisting of rubber silicone and lacquer silicone, and a silver dope.

HTS composite material formulations include a preparation of the suspension of a HTS ceramic powder of the material selected from the group consisting of, for example, YBa₂Cu₃θ₇._x (Y-Ba-Cu-0 or YBCO or Y123) and Bi₂Sr₂Ca₂Cu₃θ₁₀, a material selected from the group consisting of rubber silicone and lacquer silicone, and an ultra-fine silver powder dope. The formulations include forming a material, treating the formed material chemically, thermally, mechanically, and physically. These are resulted in HTS composite material in a form of the final HTS product. When the material is composed of the above mentioned components and the final HTS material is produced by the above-mentioned high workable material formulation, it eliminates the disadvantages of the prior art and provides highly advantageous practical results.

Employing the wet method of the ceramic mixing and preparation in form of suspension or ceramic slurry, we invented six forming methods. Four forming methods can be also considered as wet ceramic forming while two forming methods may be considered as plastic and dry forming methods. However, significant role in further technological treatment plays methods and techniques of polymer technology.

These six forming methods may be divided on two groups - substrate adhesive coating and production of bulk products from condensed ceramic mass. There are invented fourforming methods that can use adhesive film coating substrate surface There are adhesive coating of the continuous filament substrate core by the invented material suspension to produce continuous HTS filaments for combining wires, coils, and cables adhesive coating of the continuous tape substrate by the invented material suspension to produce continuous HTS tapes for combining wires, coils, and cables film casting on a silver or quartz glass chip-like substrate to produce some HTS electronics elements and devices spraying or spattering of the invented suspension on the large-size substrate surface, producing, for example, HTS radar screens

Two forming methods use preliminary condensed ceramic slurry The slurry may be condensed either into plastic mass, which comprises silicone plastic binder and, therefore, is suitable for extrusion forming Otherwise, we can apply dry pressing or hot isostatic pressing extrusion or pressing out of the plastic mass from condensed suspension to produce, for example, long-length HTS rods, tubes, rails or beams ordinary or hot isostatic pressing of the material from condensed suspension to produce products with complicated or particular shapes, such as tablets, rings, tile, bolls, 3D device details, etc

Silicone does not interact with copper, barium, and rare earth oxide content ceramics and moreover silicone prevents degradation of the high temperature superconductor properties of the high temperature superconductor ceramics, such as it is showed by different liquid solvents and polymers

When HTS ceramic powder and silicone polymer and silver dope are heated, silicone components are subjected to destruction and organic radicals are burn out from silicone, which leads to the formation of silicon, silica and carbon crystals Then, silica reacts with carbon to form silicon carbide and gas Sι0₂ + 3C → SiC + 2COT

The silicon carbide, silicon, silica and carbon are uniformly distributed in the composite material body Additionally, during high temperature thermal treatment some components of the composite ceramic material interact with the appeared silica and carbon, so as to form different composites, for example Ba₂Sι0₄, BaC0₃ etc, as it was confirmed by an X-ray phase analysis

The silicone residuals and products of their reactions with each other and ceramic components together with the silver dope significantly increase electrical conductivity and magnetic field resistance of the superconductor composite The silicone residuals and products of their reactions are also ceramic sintering aid and microwave susceptors Additionally, these residuals and products of their reactions together with silver dope prevent degradation of superconductor ceramic products, increase ductility, flexibility and strain tolerance of the shaped product This is a matter of the physical-chemical phenomenological discovery, which results in this invention

As Gmzburg's physical theory explains, the discovered and employed in this invention scientific phenomena caused of the superior electrical-magnetic properties of the invented composite material This theory says that particular micro impurities can improve superconductor properties of high temperature superconductor ceramics Silver dope and silicone residuals and products of their high temperature reactions play a role of such especially useful impurities, which actually are additives They pin electrical current vortexes significantly increasing electrical conductivity of the HTS ceramics

Homogeneous distribution of the solid micro-particles of the ceramic and silver powders in liquid silicone-based carrier causes a homogeneous suspension, making possible homogeneous and uniform adhesive precipitation cladding of the solid particles on the silver or quartz filament or tape substrate The same ceramics-silver-silicone suspension can be dried and polymerized which cause densification or condensation of the mentioned above suspension into a plastic mass This mass is suitable for an application of the pressing or extrusion forming methods

Thus, silicone content emulsion obtains both formability of high temperature superconductor material working as liquid carrier and as a plastic binder This silicone binder keeps formed cladding film or a shape of the bulk product in a stable form up to the time period of the sintering process, which provides final hardening of the products

Putting into practice these results, it makes possible an invention of the material formulation, including raw material composition, which is highly suitable for industrial conveyer and cost-effective mass production of the superior and quality assured HTS composite material The invented material composition can be performed into continuous superconductor wire, coil and broad nomenclature of the products for electrical and electronics industries

Employing the same suspension of the mentioned above composition of the raw materials, there are possible to manufacture three groups of the final HTS products that actually cover all known and potential product demands of the Electrical and Electronics industries and applications of their products in various world-wide techniques

various large-size products, for example, radar screen-shields, continuous bars and beams for levitation vehicles and other devices, electrical energy storage wheels, and non-noisy and non-wear bearings various films, super-tiny and precisely shaped electronic products, for example, chip elements for super-capacity and super-speed computers, controllers, the third generation of the wireless telephone, which will be suitable for Internet and image translation, underground telephone, supersensitive electronic devices for different applications, including medical needs, etc. continuous filament or tape combined wire, coil and cable of any electrical engineering design and nomenclature, for example, for high power electrical distribution net and smaller and power motors, generators, transformers, super-stable and super-power magnets, for example, for MRI diagnostic system and an accelerator of the elementary physical particles.

The novel features, which are considered as characteristics for the present invention, are set forth in particular in the appended claims.

Brief Description of the Drawings

Shown on the Figures 1-7 high temperature superconductor (HTS) composite material can be in form of coated substrate elements from the group consisting of a filament, a wire, a tape, a coil, a chip, and a screen and in article forms from the group consisting of long-length and different bulk-shaped structures that do not apply substrates.

Figure 1 is a view showing an example of the base for HTS electronic chip with one-layer HTS film where 1 = a chip substrate, 2 = one-layer HTS film from invented HTS composite material.

Figure 2 is a view showing an example of the base for HTS electronic chip with multi-layer HTS film where

1 = a chip substrate, 3 = 3D HTS multi-layer film from invented HTS composite material.

Figure 3 is a view showing an example of the large-size HTS screen on the balk shaped substrate where 4 = a bulk shaped substrate, 5 = HTS layer from invented HTS composite material

Figure 4 is a view showing an example of the continuous HTS filament or wire on filament core substrate where 6 = filament core substrate, 7 = HTS layer from invented HTS composite material, 8

= polymerized siiicone sheath

Figure 5 is a view showing an example of the construction of the continuous HTS tape where

9 = tape substrate, 10 = HTS layer from invented HTS composite material Figure 6 is a view showing examples of the long-length extruded HTS bulk structure where

11 = HTS bulk structures with simple and symmetrical shape from invented HTS composite material: a - rod, b - beam, c - tube or capillary, d - rail, and e - cup.

Figure 7 is a view showing examples of the pressed and hot isostatic pressed HTS bulk structure where

12 = HTS bulk structures with simple and complicated shapes from invented HTS composite material: a - tablet, b - lens, c - tile, d - ring, and e - rungs.

Figure 8 is a photo picture of the microstructure of the invented HTS composite material. The photo picture is produced by electronic microscope from a replica of the sample of the HTS composite material with magnification factor 6,000 and further photo enlargement in 10 - 12 times.

On the Figure 8 are easy seen small-size silicone residuals and silicon products ("silica") between significantly larger particles of Y123 ceramics. "Silica" obtains better contacts of the sintered ceramic particles, i.e., increasing material integrity, which is important for electric current flow. "Silica" also prevents degredation of ceramic particles isolating them from outside environment, which significantly increases reliability and durability of the invented HTS composite material. Seen on the Figure 8 agglomerations of "silica" have helix shape, which is laid before sintering by initial silicone-polymer binder. It causes significant improving strain tolerance and ductility of the invented HTS composite material.

Best Mode of Carrying Out the Invention

Superconductors can transmit or store enormous amounts of electrical current with perfectly stable current characteristics and without loss as well as providing unique levitation bearing and magnetic effects. All superconductor applications increase or stabilize by several times the electrical and magnetic characteristics of the final item while in some cases superconductor products result in or suggest unpredictable technical innovations on the base of unstudied phenomena. These advantages and effects relate to all items and products of the Electrical and Electronics industries and will multiply their economic value to all industries and for all products that use electrical and magnetic energies.

Recently discovered High Temperature Superconductor (HTS) ceramics can work at the temperature of liquid nitrogen or even at higher temperatures. This allows wide commercializing of HTS products since use of liquid nitrogen coolant saves a great deal of cost when compared to previously known superconductor alloys and their applications at the temperatures of liquid hydrogen or helium.

More 25 known U.S. patents consider various organic-polymer compound materials as a base of the superconductor products. However, organic- based superconductors can not now be considered for industrial applications due to unacceptably low electrical and magnetic properties of the organic-based body.

More 100 patents have been issued covering technological methods of the use of the HTS ceramics for production of HTS wire, tape and various bulk products using yttrium and bismuth oxides or similar rare-earth ceramic compounds. Our analysis showed that most of these patents use two basic production methods for manufacturing HTS filament or tape that combine into HTS wire. They are either filling a metal (usually silver) tube with a superconductor ceramic powder or depositing the same ceramic material on a silver tape substrate using some advanced physical methods, such as laser-beam deposition, which can be named "coating" or "cladding". After the tube filling, the patents usually propose different methods of die- drawing, rolling and heating of the tube or just heating and sintering of the deposited (coated or clad) ceramic powder which should provide the required integrity and stability of the ceramic body.

While the superconductor industry is still new and just anticipates wide commercialization, the approaches mentioned above are paths for the conventional scientific and engineering paradigm. To date, all university, corporate and government labs that are conducting research in this field have been unable to develop inexpensive production methods for long-length HTS wire and other products with a high level of electrical, magnetic and structural properties. Additionally, productivity using current processes is too low and the scrap percentage is much too high.

These negatives must be overcome before commercialization is feasible. As a practical matter, used now material formulations and methods of the treatment of the ceramic powder are costly and unavoidably cause a lot of defects in integrity or homogeneity of the long-length HTS filament or tape, while production of long-length beams or rails is almost impossible.

We would like to notice that Materials Science and Ceramic Engineering sure relate these disadvantages to the dry method of the material preparation that cannot obtain for acceptable preparation cost complete uniform homogenization and compaction of the mixture of the solid particles of the ceramic and silver powders. As for us, these worldwide efforts show that used HTS ceramic formulations are not workable and obviously cannot be successfully applied. Meanwhile, this problem is known in Materials Science and Ceramic Engineering, as a material formulation problem.

Raw compositions of the ceramic materials usually include components and additives that control technological and consumer properties of ceramics. There are using additive and sintering aid systems that allow achieving material formability, controlled sintering and required consumer properties of ceramics. There are also known two formulation approaches - either in dry or wet conditions. Applying wet formulation method, we can prepare a suspension of the raw materials solid particles in some liquid carrier, which is usually water for silicate or '^■ π-iip rora ics However, if water destroys ceramics properties, there are used „ . _... _^πoi or polymer solutions and emulsions. Wet formulation method can obtam complete homogeneous and uniform mixing and distribution of the solid particles in liquid suspension even though there are multi-fraction composition of the particles with different crystal densities

For non-plastic ceramic powder, as a raw material, such as alumina or HTS ceramic powder, there are also recommended organic or inorganic binder additives, which make possible forming non-plastic ceramic powder using slip casting and extrusion methods The special additives and aids can influence on and control of the ceramic preparation process and properties of the sintered ceramics Therefore, each type or class of ceramic materials certainly needs a special material formulation, which usually includes a system of additives and aids However, until now a particular system of the additives and aids for HTS ceramics has not been invented

This patent application puts into practice an integration of two scientific and engineering discoveries that make possible an appropriate formulation of the HTS composite material on the base of HTS raw material ceramic powder

The matter of the first discovery is followed After firing and hardening (sintering) of the HTS ceramics formed with a contribution of silicone, the invented HTS composite material keeps silicone residuals, including Si, C, and SiC micro- crystals and products of the thermo-chemical reactions of these residuals with different oxides of the HTS ceramics These residuals and products with a specifically determined percentage of Ag powder are homogeneously distributed within the HTS ceramic body These additives of the HTS composite material significantly increase electric conductivity and magnetic resistance and they also sufficiently increase and improve compressive and tensile strengths, ductility, and ambient resistance of HTS composite material and its shaped (formed) products

The matter of the second and concurrent scientific discovery consists of the application of one basic principle of Materials Science and Ceramic Engineering Only liquid state suspension can cause homogeneous and uniform mixing and distribution of the solid particles in the liquid carrier volume This automatically causes, for example homogeneous precipitation on and adhesive coating of the substrate plate, filament or tape Vapoπzation-densification and polymerization of the homogeneous solid particle dispersion into a ceramic mass should produce a homogeneous particle compound with a silicone binder, which should be suitable for an extrusion or pressing

All applied in the invention cost effective forming methods result in high workability, adaptability for different products, that shown on Figures 1 -7, reliable quality and process control of scrap-free manufacturing This makes it possible cost- effective production of all necessary HTS products for Electrical and Electronics industries

In accordance with the present invention a HTS composite material consists of a sintered compound of HTS ceramics, sintering residuals and products of the silicone material selected from the group consisting of rubber silicone and lacquer silicone, and a silver dope

We can easy see on the Figure 8 small-size silicone residuals and silicon products ("silica") between significantly larger particles of Y123 ceramics "Silica" obtains better contacts of the sintered ceramic particles, i e , increasing material integrity, which is important for electrical current flow "Silica" also prevents degradation of the ceramic particles isolating them from outside environment, which significantly increases reliability and durability of the invented HTS composite material Seeing on the Figure 8 agglomerations of "silica" have spiral or helix shape, which is laid before sintering by initial silicone-polymer binder It causes significant improving strain tolerance and ductility of the invented HTS composite material in forms of useful products

Silicone residuals and products of their reactions with HTS ceramic compound inhibit degradation of superconductor properties of the HTS composite material under impacts of the presented in natural atmosphere C0₂ and H₂0 gases and nitrogen or oxygen coolants. As the result, HTS composite material keeps superconductor electrical and magnetic properties after 700 - 1 ,000 cyclic submerges in-out liquid nitrogen in comparison with known HTS ceramics that lose their superconductor properties after 100 - 140 submerges into liquid nitrogen.

The invented high temperature superconductor composite material is a material which works at liquid nitrogen and higher temperatures K > 77 with critical current density J_c > 10⁴A/cm² and value of critical magnetic field H_c within the range of 0.1 - 30 Tesla. In particular, it can work with the critical current density J_c of 10⁵A/cm²-10⁶A/cm². The new high temperature superconductor (HTS) composite material in accordance with present invention has specific impact strength within the range of 0.5-2 kg.cm/cm², and a long-time durability compatible with a conventional metal wire at working temperatures and conventional ambience.

In the new material the synthetic silicone rubber or lacquer has molecular weight in the range of 20,000-800,000, such as a synthetic silicone rubber HO-[-Si(CH₃)₂0-]-H with a molecular weight 30,000 - 40,000, and this synthetic silicone rubber or lacquer should be presented in an emulsion of the components in the mass ratio 1 % - 15%, for example, 4% or 6%.

If we apply a silicone rubber, the suspension mixture should include adding diethylaminmethylthrietoxisilane polymerisation aid in a ratio of 2% - 15%, for example, five weight percent of the weight of the silicone rubber, to accelerate polymerization process.

The shaping of the HTS material can be performed either by direct applying of the mentioned above suspension, for example, by using chemical- adhesive coating method or by pressure of the mass condensed from the same suspension. Pressure can be provided, for example, at 300 MPa either at a room or higher temperature, such as 330°C.

The forming methods to produce a continuous high temperature superconductor filament or tape (Figures 4 and 5) include a use of the substrate filament or tape. Substrate materials selected from the group consisting of a metal or alloy, for example silver, or quartz glass or ceramics or carbon fiber or carbon fiber fabric or glass-like carbon. Then we provide coating a surface of the substrate by at least one layer of the HTS compound material; processing the coating substrate by a process selected from the group consisting of a chemical processes, a physical processes and a thermal processes, using a conveyor consequence of the steps; and sheathing of the thusly produced product with a material selected from the group consisting of a polymer material and/or a metal sheath.

An adhesive primer layer is applied on the filament or tape substrate. The substrate filament or tape can be also composed of silver or quartz glass. Then a high temperature superconductor composite material based on suspension mixture of high temperature superconductor ceramics with silicon-organic polymer and silver powder dope is clad on the adhesive layer, and finally a protective layer of silicon- organic material could be applied on the outer surface and polymerized.

The performance includes precipitating an adhesive primer based on epoxy lacquer or pitch with an addition of a silver powder and a polymerization aid on the filament or tape based on the quartz glass or metal, which should be silver.

Furthermore a suspension mixture of three mentioned above major components of the high temperature superconductor composite material is produced while a solvent for silicone emulsion is either toluene or acetone.

The invented material preparation method includes adhesive cladding of superconductor compound layer on the mentioned above adhesive primer layer from the mentioned above suspension.

The invented material preparation method includes finally hardening of the high temperature superconductor filament or tape by ceramic sintering in an electrical furnace during 4 - 72 hours in excess of air or oxygen flow at 700 - 955°C (for example, 930 - 950°C if we use Y-Ba-Cu-O ceramic composite). Otherwise finally hardening of the high temperature superconductor filament or tape cladding layer is provided by ceramic sintering in a microwave supported furnace during 0 3 - 10 hours in excess of air or oxygen flow at 700 - 950°C

The thusiy-produced high temperature superconductor filaments or tapes are compacted and twisted to form a designated high temperature superconductor wire A silicone polymer covering to perform sheathing and a sealing of the high temperature superconductor wire is provided by applying a vulcanization technique Otherwise the high temperature superconductor wire can be stretched through copper, silver or another capillary or a tube Finally, the flexible HTS wire can be wound in a coil or combined into a cable

The special advantage of the proposed invention is a high workability and formability of the invented raw material composition It makes it possible to provide conveyor production of the quality assured high temperature superconductor products for all areas of the possible application of the high temperature superconductors using the same composition of the raw materials in the same form of the suspension (superconductor compound suspension) The suspension composition includes three major components There are HTS ceramic powder, silicone emulsion in toluene or acetone solvent, and silver powder dope

Thus, the first step of the formulation of the HTS composite material is preparation of the raw materials composition and making ready for use all additives and ingredients The typical second material performance step is shaping or forming of the green material Third step includes a few physical and thermal treatments of the shaped green material, and fourth step consists of a high temperature sintering process, which converts green material into useful HTS composite material

An invented adjustment of the formulation of the HTS composite material is provided for six shaping (forming) methods, including

1 ) and 2) Adhesive coating (cladding) of powder compound suspension on metai or alloy or silver or ceramics or quartz glass or carbon fiber filament or tape substrate to produce continuous HTS filaments or tapes that can be further combined in wire, coil and cable These products have to satisfy requirements of all traditional electrical engineering applications, having significant advantages, such as smaller and powerful electrical motors, generators, turbine rotors, transformers, reliable distribution nets and some innovative or unique advanced applications, such as storage magnet energy systems (SMES), MRI, and super-power magnets for physical particle accelerator

3) Molding (casting) of one or several thin film layers of the invented HTS suspension on metal or alloy or silver or ceramics or quartz glass or carbon fiber fabric substrate to produce two or three-dimensional high temperature superconductor films. The structure of the HTS film can copy the substrate shape structure or its buffer layer. Otherwise, a laser can burn out an especially precise high temperature superconductor two- or three-dimension structure of the electronic elements The films can be applied, for example, for super-capacity memory and super high-speed elements of computers and controllers, various supersensitive electronic devices, such as wireless and underground telephone systems and their use for Internet and imaging translation

4) Spraying, spattering or casting (molding) of the invented HTS composite suspension on metal or alloy or silver or ceramics or quartz glass or carbon fiber fabric or glass-like carbon substrate surface of the large perimeters to produce radar screens, super-sensitive and superpower radio antennas and telescopes.

5) An extrusion or pressing out of the condensed plastic mass from the invented HTS composite suspension to produce large size and long-length HTS products, such as rods, beams, rails and plates for levitation bases and durable energy storage wheels

6) Ordinary pressing at room temperature or hot isostatic pressing of the condensed plastic mass from the invented HTS composite suspension to produce similar products that listed in above point 5 as well as products with particular shape, for example, tablets or disks. Five examples of the raw material compositions of the invented HTS composite suspensions that are suitable to produce various HTS composite materials and different products presented herein below.

Example 1

A raw materials composition includes a superconductor ceramic powder YBa₂Cu₃0₇ - 92 5 weight parts, organo-silicate elastomer or silicone rubber HO-[-Sι(CH₃)₂0-]-H - 5 weight parts, dialkylaminomethyltrialkoxysiiane, which is polymerization aid - 5 weight percents from the weight of the silicone rubber; silver powder - 2 5 weight part, all in a toluene solution.

Example 2

A raw materials composition includes a superconductor ceramic powder YBa₂Cu₃0₇ - 92.5 weight parts, polyvmyldimethylsiloxane rubber - 5 weight parts, dialkylaminomethyltπalkoxysilane - 4 5 weight percents from the weight of the silicone rubber, silver powder - 2.5 weight percent, all in a toluene solution, 300 weight percents of toluene from the weight of the silicone rubber.

Example 3

A raw materials composition includes a superconductor ceramic powder YBa₂Cu₃0₇ - 92.5 weight parts;

HO-[-Sι(CH₃)₂0-]-H - 2 5 weight percent, polyvmyldimethyl silcoxane rubber - 2 5 weight percent dialkylaminomethyltπalkoxysilane - 5 weight percents from the weight of the silicone rubber, silver powder - 2 5 weight percent, all in an toluene solution, 200 weight percents of toluene from the weight of the silicone rubber.

Example 4

A raw materials composition includes a superconductor ceramic powder Bι_zSz_zCa₂Cu₃O₁₀ - 92 5 weight parts, organo-si cate elastomer rubber HO-[-Sι(CH₃)₂0-]-H - 5 weight parts, dialkylaminomethyltπalkoxysilane - 5 weight percents from the weight of the silicone rubber, silver powder - 2 5 weight percent, all in a toluene solution

Example 5

A raw materials composition includes a superconductor ceramic powder Bι_zSz_zCa₂Cu₃O₁₀ - 92 5 weight parts,

HO-[-Sι(CH₃)₂0-]-H - 5 weight parts, dialkylaminomethyltπalkoxysilane - 5 weight percents from the weight of the silicone rubber, silver powder - 2 5 weight parts, all in a toluene solution , 400 weight percents of toluene from the weight of the silicone rubber

A formulation of the HTS ceramic composite to produce high temperature superconductor filament is illustrated by the following example

Example 6

A silver filament with the thickness of 10 micron is degreased by acetone, then immersed into a ceramic porcelain cup or vessel with epoxy glue dissolved in acetone with the silver powder, hardened by malein or phtalein anhydride (30-35 weight parts from the weight of the epoxy resin, hardened at temperature of 130°C). Then the filament is immersed into a next ceramic cup or vessel with a suspension consisting of a powder of yttrium ceramics (Y-Ba-Cu-O), silicone polymer emulsion in toluene mixed by ultrasound mixer and silver in form of powder. Then the filament is removed from the bath and orientation of the particles of polymer-ceramic compound in a magnetic field of 3 Tesla is provided. Then the filament with the applied and oriented coating is introduced into a thermostat with heating from 100 to 320°C during 0.5 hour In order to increase the stability of the properties of the filament to action of magnetic fields, the filament is subjected to irradiation treatment with the dose of 5.10⁴ Gy. Then, the filament is sintered in an electrical tube furnace at the temperature of 945 °C in oxygen flow during 24 hours.

A material formulation to produce a HTS composite material in form of a solid disk is illustrated by the following example.

Example 7

A silicon-organic rubber with polymerizing agent are dissolved in toluene are introduced into the mixture, the mixture is stirred, the polymeric component of the material is mixed with the ceramics and silver in a corresponding ratio in a glass or ceramic vessel and slow heated at small vacuum impact until the solvent is evaporated and uniform mixture is produced by ultrasound and stirrer. The obtained mixture is additionally dried and introduced into a press mold and pressed with the pressure of 300 MPa in a magnetic field of 1 -10 Tesla. Then the product is removed from the press mold, and after 24 hours of soaking is subjected to a thermal treatment at 100°C - 1 hour, 120°C - 1 hour, 150°C - 1 hour, 200°C - 1 hour. In order to impart . . cind strength to the product, it is sintered at a temperature of 950°C in in _v curing 24 hours. A product can be made, for example, in form of disc or tablet, with a diameter of 30mm and thickness 3 - 4mm

Example 8

The product of the invented material based on the bismuth ceramics Bι₂Sr₂Ca₂Cu₃O₁₀ was produced in a similar way, as it is described in Example 7 However, in order to impart to the product the superconductor properties the annealing of the product was performed at temperature 950°C in air atmosphere during 70 hours

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of methods and constructions differing from the types described above

While the invention has been illustrated and described as embodied in high temperature superconductor composite material, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims

Claims

1. A high temperature superconductor composite material capable working at liquid nitrogen and higher temperatures K > 77, comprising a sintered compound of high temperature superconductor ceramics; a silver dope; silicone residuals in form of silica and silicon; and sintering products of interaction of said sintered compound and said silver dope with silicone material.

2. A high temperature superconductor composite material as defined in claim 1 , wherein said sintered compound of said high temperature superconductor ceramics is YBa₂Cu₃0₇._x ceramics.

3. A high temperature superconductor composite material as defined in claim 1 , wherein said sintered compound of said high temperature superconductor ceramics is Bi₂Sr₂Ca₂Cu₃O₁₀ ceramics.

4. A high temperature superconductor composite material as defined in claim 1 , wherein said silicone material is rubber silicone.

5. A high temperature superconductor composite material as defined in claim 1 , wherein said silicone material is lacquer silicone.

6. A high temperature superconductor composite material, as defined in claim 1 , wherein said a high temperature superconductor composite material comprising said silicone residuals and sintering products in the mass ratio 1 % - 6%.

7. A high temperature superconductor composite material, as defined in claim 1 , wherein said a high temperature superconductor composite material comprising said silver powder dope in the weight ratio 0.5% -15%.

8. A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material forms an element selected from the group consisting of a filament, a wire, a tape, a coil, a chip, a screen, a short bulk-shaped structure, a ring, a disk, a tablet, a long-length bulk-shaped structure, a rod, a beam, a tube, and a rail.

9. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver dope powder in silicone emulsion in toluene or acetone solvent forms at least one layer or one film-layer adhesive coating, cladding or spraying or spattering said high temperature superconductor composite material on a continuous metal, or an alloy, or a silver, or ceramics or quartz glass or carbon fiber or carbon fiber fabric substrate element from the group consisting of a filament, a wire, and a tape.

10. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver dope powder in silicone emulsion in toluene or acetone solvent forms at least one layer or one film-layer adhesive coating or cladding or spraying or spattering said high temperature superconductor composite material on a substrate element from the group consisting of a coil, a screen, and a bulk-shaped article.

11. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver dope powder in silicone emulsion in toluene or acetone solvent forms at least one layer or one film-layer of adhesive coating, cladding or spraying said high temperature superconductor composite material on a metal, or an alloy, or a silver, or ceramics or quartz glass or carbon fiber fabric substrate element from the group consisting of a chip and an electronic element.

12. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver dope powder in silicone emulsion in toluene or acetone solvent and the said suspension is molded, cast or injected into mould to form a small or large bulk-shaped article, a plate, a ring, a cup, and a disk.

13. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver dope powder in silicone emulsion in toluene or acetone solvent is condensed into ceramic-plastic mass to press at room or higher temperature a simple or complicated bulk-shaped structure, a ring, a disk, a cylinder, a vessel cup, and a tablet.

14. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver dope powder in silicone emulsion in toluene or acetone solvent is condensed into ceramic-plastic mass to extrude a long- length bulk-shaped structure, a rod, a beam, a tube, and a rail.

15. A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material has increased in 1.5 - 5 times electrical conductivity and magnetic resistance regarding initial high temperature superconductor ceramic powder, obtaining critical current density J_c at least 10" A/cm², and value of the critical magnetic field H_c within the range of 0.1 - 30 Tesla.

16. A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material keeps its superconductor properties after at least 700 cyclic submerges into liquid nitrogen in comparison with initial high temperature superconductor ceramics that lose their superconductor properties after 100 - 140 cyclic submerges into liquid nitrogen.

17. A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material has working reliability and durability in nitrogen coolant environment that are comparable with those of a conventional copper wire in natural outdoor environment

18 A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material has significantly increased strain tolerance and flexibility obtaining specific impact strength within the range of 0 5 - 2 kg cm/cm²

19 A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material has significantly increased ductility that allows cutting, polishing and drilling applying usual for ceramic materials tools and instruments

20 A method of production a high temperature superconductor product from composite comprising the steps of making a suspension mixture of a superconductor ceramic powder, silicone material selected from the group consisting of rubber silicone and lacquer silicone, and an fine silver powder dope, forming a product from the suspension , treating the formed product by a process selected from the group consisting of a chemical process, a physical process and a thermal process, and sintering the product

21. A method as defined in claim 20, wherein the rubber silicone or lacquer silicone have a molecular weight within the range of 20,000-800,000 and is present in the material in the mass ratio 1 % - 15%

22. A method as defined in claim 20, wherein the rubber silicone is a synthetic silicone rubber HO-[-Si(CH₃)₂0-]-H with a molecular weight 30,000- 40,000.

23. A method as defined in claim 20, wherein said treating includes homogenizing the mixture by ultrasonic vibration impact during 0.5 -60 seconds.

24. A method as defined in claim 20; and further comprising adding diethylaminmethylthrietoxisilane polymerization aid in ratio of 2% - 20% percent of the weight of the silicone rubber or silicone lacquer, to accelerate polymerization process of silicone rubber or silicone lacquer.

25. A method as defined in claim 20 ; wherein the forming process includes using a process selected from the group consisting of application of pressure at 1.0 - 400 MPa or extrusion or molding or slip casting or coating or spraying or spattering and their combination.

26. . A method as defined in claim 20; and further comprising providing a substrate selected from the group consisting of a metal, preferably silver, or an alloy or ceramics or quartz glass or carbon fibers or carbon fabric or glas-like carbon; coating a surface of the substrate by at least one layer of the high temperature superconductor composite material and subjecting the coated product to said physical and thermal treating and sintering;

27. . A method as defined in claim 26 ; and further comprising the step of preliminary degreasing of the surface of the metal or alloy substrate by acetone.

28. . A method as defined in claim 26 ; and further comprising the step of immersion in a vessel with or brushing on a metal or an alloy substrate an adhesive compound suspension comprising of epoxy lacquer or glue or pitch with an addition of a silver fine powder and a hardening aid; and thermal polymerization of the adhesive compound

29. . A method as defined in claim 20 ; and further comprising the step of immersion in a vessel with or brushing on a said substrate a said compound suspension providing precipitation adhesive cladding or coating a green high temperature superconductor compound layer on the said substrate in form of continuous filament or tape or screen or chip or bulk shaped product .

30. A method as defined in claim 20; and further comprising the step of spraying or spattering a said compound suspension providing precipitation adhesive cladding or coating a green high temperature superconductor compound layer or film on the said substrate in form of a screen or a chip or a surface of the bulk shaped product.

31. A method as defined in claim 20, wherein said treating the formed article includes magnetic orientation of ceramic particles by applying an outside magnetic field of 1-10 Tesla.

32. A method as defined in claim 20, wherein said treating includes polymerization and hardening an article produced from the high temperatures superconductor composite material with a low temperature heating at slowly raising temperature within the range of 20°C-200°C during 0.5 - 10 hours.

33. A method as defined in claim 20; and further comprising polymerization of the high temperature superconductor composite material in form of a layer or a film or bulk product during 0.5 - 60 minutes at temperature with the range of 100°C - 320°C in a steam autoclave.

34. A method as defined in claim 20; wherein said treating the formed and polymerized article comprises the step of irradiation of the high temperature superconductor composite material within a dose range of 10²-10⁶ Gy.

35. A method as defined in claim 20, wherein said sintering includes sintering in an electrical furnace during 4 - 72 hours in excess of air or oxygen flow at 800°C-950°C.

36. A method as defined in claim 20, wherein said sintering includes sintering in a microwave supported electrical furnace during 0.5 - 16 hours in excess of air or oxygen flow at 700°C-950°C.

37. . A method as defined in claim 20; and further comprising compacting or bending or twisting and binding the high temperature superconductor filament or tape so as to form a high temperature superconductor wire or coil or cable.

38. A method as defined in claim 20; and further comprising providing a sheathing of the thusly produced product with a material selected from the group consisting of a metal, an alloy, ceramics, a silicone polymer material, quartz glass and a carbon fabric.

39 . A method as defined in claim 20; and further comprising stretching the high temperature superconductor wire through a structure selected from the group consisting of a metal or an allow, or ceramics or quartz glass or glasslike carbon in form of a capillary or a tube or 3D hollow figure or a body.

8 A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite mateπal is in the form of an element selected from the group consisting of a continuous filament, a wire and a tape or a coil, a chip, a screen, a short bulk- shaped structure, a ring, a disk, a tablet, a long-length bulk-shaped structure, a rod, a beam, a tube, and a rail.

9 A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver powder in silicone emulsion in toluene or acetone solvent is in the form of at least one layer or one film-layer adhesive coating, cladding or spraying said high temperature superconductor composite material on a continuous metal, or an alloy, or a silver, or ceramics or quartz glass or carbon fiber or carbon fiber fabric substrate element from the group consisting of a filament, a wire, and a tape.

10. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver powder in silicone emulsion in toluene or acetone solvent is in the form of at least one layer or one film-layer adhesive coating, cladding or spraying or spattering said high temperature superconductor composite material on a substrate element from the group consisting of a coil, a screen, and a bulk-shaped article.

11. A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver dope powder in silicone emulsion in toluene or acetone solvent is in the form of at least one layer or one film-layer of adhesive coating, cladding or spraying said high temperature superconductor composite mateπal on a metal, or an alloy, or a silver, or ceramics or quartz glass or carbon fiber fabric substrate element from the group consisting of a chip and an electronic element. -30-

12 A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver powder in silicone emulsion in toluene or acetone solvent and the said suspension in the form of slurry mould to form a small or large bulk-shaped article, a plate, a ring, a cup, and a disk.

13 A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver powder in silicone emulsion in toluene or acetone solvent is in the form of condensed ceramic-plastic mass to press at room or higher temperature a simple or complicated bulk-shaped structure, a ring, a disk, a cylinder, a vessel cup, and a tablet.

14 A high temperature superconductor composite material, as defined in claim 1 , wherein a suspension mixture of said high temperature superconductor ceramic powder and said silver powder in silicone emulsion in toluene or acetone solvent is in the form of condensed ceramic-plastic mass to extrude or provide injection moulding, of a long-length bulk-shaped structure, a rod, a beam, a tube, and a rail.

15 A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite mateπal is a material which works at liquid nitrogen and higher temperatures K>77 with critical current density J_r at least ICΑ/cm², and value of the critical magnetic field H_c within the range of 0. - 30 Tesla,

6, A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material keeps its superconductor properties after at least 700 cyclic submerges into liquid nitrogen in comparison with initial high temperature superconductor ceramics that lose their superconductor properties after 100 - 140 cyclic submerges into liquid nitrogen

17. A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite material has -31 -

increased strain tolerance obtaining specific impact strength within the range of 05 - 2 kg cm/cm'"

18 A high temperature superconductor composite material, as defined in claim 1 , wherein said high temperature superconductor composite matenal is a material with increased ductility that allows its cutting, polishing and drilling

19 A method of production a high temperature superconductor material and a product from this material, comprising the steps of making a suspension mixture of intermixed components including a superconductor ceramic powder, silicone material, and an ultra-fine silver powder, forming a product from the suspension, treating the formed product by a process selected from the group consisting of a chemical process, a physical process and a thermal process, and sintering the product

20 A method as defined in claim 19, wherein the silicone has a molecular weight within the range of 20,000-800,000 and is presented in the composition dry mixture in the mass ratio 1 %-15% to HTS ceramic powder

21 A method as defined in claim 19, wherein the silicone is a synthetic silicone rubber HO-[-Sι(CH₃)₂O-]-H with a molecular weight 30,000-40,000

22 A method as defined in claim 19, wherein said treating includes homogenizing the mixture by ultrasonic vibration impact during 0.5-60 seconds

23. A method as defined in claim 19; and further comprising adding diethylaminmethylthπetoxisilaπe polymerization aid in ratio of 2% - 20% percent of the weight of the silicone, to accelerate polymerization process of silicone

24 A method as defined in claim 19, wherein the forming includes using a process selected from the group consisting of application of pressure at -32-

1 0 Pa-45QMPa or extrusion or moulding or slip casting or coating or spraying or spattering

25. A method as defined in claim 19; and further comprising providing a substrate selected from the group consisting of a metal, preferably silver, or an alloy or ceramics or quartz glass or carbon fibers or carbon fabric or glass-like carbon, coating a surface of the substrate by at least one layer of the high temperature superconductor composite mateπal and subjecting the coated product to said physical and thermal treating and sintering

26. A method as defined in claim 25; and further comprising the step of preliminary decreasing of the surface of the metal or alloy substrate by acetone.

27, A method as defined in claim 25; and further comprising the step of immersion in a vessel with or brushing (pointing) on a metal or an alloy substrate an adhesive compound suspension comprising of epoxy lacquer or glue or pitch with an addition of a silver fine powder and a hardening aid; and thermal polymerization of the adhesive compound

28. A method as defined in claim 19; and further comprising the step of immersion in a vessel with or brushing or painting on a said substrate said compound suspension providing precipitation adhesive cladding or coating a green high temperature superconductor compound layer on the said substrate in form of continuous filament or tape.

29. A method as defined in claim 19, and further comprising the step of spraying or spattering said compound suspension providing precipitation adhesive cladding or coating a green high temperature superconductor compound layer or film on the said substrate in form of a screen or a chip or a surface of the bulk shaped product,

30. A method as defined in claim 19, wherein said treating the formed article includes magnetic orientation of ceramic particles or grain alignment by applying an outside magnetic field of 1-10 Tesla

31 A method as defined in claim 19, wherein said treating includes polymerization and hardening an article produced from the high temperatures superconductor composite material with a low temperature heating at slowly raising temperature within the range of 20°C-200°C during 0,5 - 10 hours.

32. A method as defined in claim 19; and further comprising polymerization of the high temperature superconductor composite material in form of a layer or a film or bulk product during 0.5-60 minutes at temperature with the range of 100°C - 320°C in a steam autoclave.

33 A method as defined in claim 20, wherein said treating the formed and polymerized article comprises the step of irradiation of the high temperature superconductor composite material within a dose range of 10²-10^β Gy.

34. A method as defined in claim 20, wherein said firing process includes sintering in an electrical furnace during 4-48 hours in excess of air oxygen flow at 800°C - 1200°C.

35 A method as defined in claim 20, wherein said firing process includes sintering in a microwave supported electrical furnace during 0.3-10 hours in excess of air or oxygen flow at 750°C - 1150°C.

36. A method as defined in claim 19, and further comprising compacting or joining on bending or twisting and binding the high temperature superconductor filament or tape so as to form a high temperature superconductor wire or coil or cable package.

37. A method as defined in claim 19; and further comprising providing a sheathing of the thusly produced product with a material selected from the group consisting of a metal, an alloy, ceramics, a silicone polymer material, quartz qlass and a carbon fabnc STATEMENT UNDER ARTICLE 19

The Examiner indicated that U.S Patent 5,902,774 to Muranaka, et al is document of particular relevancy in category X

Muranaka, et al discloses a method of joining, binding, interposing and combining two or more tapes or flat wires, by different materials and binders, including silicone or polysiloxane binder, which is applied on the wire (Col.6, lines 20- 30) The purpose of his method is to produce a multi-wire package or structure in a form of a coil

In contrast, the applicant's invention is a high temperature superconductor (HTS) composite material, comprising a sintered compound of intermixed components including HTS ceramics, a silver dope, and sintering products of interaction of said superconductor ceramics and said silver dope with silicone material, and a method of producing the same.

Muranaka, et al considers only one type of the superconductor wire, which is produced by filling a silver or silver alloy small diameter tube with oxide superconductor powder and coating the tube with silicone (multi-layer structure with separate, non-intermixed layers), with thermal treatments and mechanical rolling and flattering of the charged silver alloy tube. This method of production of High Temperature Superconductor (HTS) wire or tape is well known as "powder in tube" or PIT method.

It has noting to do with the sintered compound of 3 intermixed components of the applicant's invention, and chemical reactions between them involved According to Muranake, et al any binder, including silicone resin is applied on silver sheathes as a supporter of the multi-layer construction or package It means that such binder coats the outer surface of the silver sheath or shell and therefore cannot influence the properties or production process of the HTS ceramic composition, which is charged inside or within said silver sheath or shell. Certainly, such binder can not be considered as a part of the HTS material composition with the 3 intermixed components which form the inventive sintered compound.

According to the method of Muranaka, et al the multi-layer composition of silver tapes superposed with protective layers that may include silicone resin and other organic binders, should be heated up to temperatures 600°C and higher, which causes full burning out and evaporation of the organic binders and generation of silicone residuals However, Muranaka et al do not mention such residuals in any place of the issued patent. In any event, they can not be a part of a sintered compound of 3 intermixed components of the present invention.

In contrast, in the present invention the silicone components of the HTS raw materials composition of 3 intermixed components plays several roles. This component allows workable and inexpensive processing, forming of broad spectrum of useful material forms, including coated continuous wire, tape, screen and other extruded and pressed bulk products with determined advanced structural properties and desired electrical conductivity and magnetic susceptibility at liquid nitrogen and higher temperatures X-ray analysis found sintering products of interaction of said superconductor ceramics and said silver dope with silicone material The silicone residuals and products of said interaction, such as CuYSi, Ba²SiO₄ and especially SiC induce advanced and innovative levels of reliability, durability, ductility and strain tolerance.

The new features of the present invention as defined in the current claims are not disclosed in the patent to Miranaka and can not be derived from it as a matter of obviousness.