巴西专利BR112012033085B1 superconducting structure, and, method to produce a superconducting structure

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专利摘要:
SUPERCONDUCTOR STRUCTURE, AND, METHOD TO PRODUCE A SUPERCONDUCTOR STRUCTURE. A high temperature superconducting structure is described including: a substrate on which at least one damping layer is deposited, a superconducting layer on the damping layer, the superconducting layer composed of superconducting material that forms at least two substantially parallel superconducting filaments extending continuously along the length of the substrate, in which at least two superconducting filaments are separated from each other by at least one insulating strip, in which the insulating strip extends continuously along the length of the substrate and is composed of insulating material with a resistivity greater than about 1m (OMEGA) cm. Methods of producing high temperature superconductors are also disclosed.
公开号:BR112012033085B1
申请号:R112012033085-3
申请日:2011-06-22
公开日:2020-10-20
发明作者:Venkat Selvamanickam；Senthil Sambandam
申请人:University Of Houston System；
IPC主号:

专利说明:

BACKGROUND OF THE INVENTION Description Field
[001] The present description generally refers to high temperature superconductors (HTS) and, more specifically, to a multifilament AC-tolerant superconductor and method of forming the same. Description Basics
[002] The potential for high temperature superconductors (HTS) to efficiently transmit, generate, transform, use and store electrical energy is recognized. In particular, more efficient electrical power systems depend on more efficient wire technology. Advances in the past have allowed fragile HTS materials to be formed into kilometers-long cables capable of transmitting about two hundred times more current than conventional copper and aluminum conductors of the same physical dimensions. Recent research on HTS materials provides potential for the economically viable use of such materials in the energy industry, including applications for energy generation, transmission, distribution and storage. The use of HTS devices in the energy industry would result in a significant reduction in the size (ie, footprint) of electrical energy equipment, reduced environmental impact, greater safety and greater capacity compared to conventional technology.
[003] Two generations of HTS yarn materials have been previously explored. The first generation (hereinafter "1G") of HTS wires included the use of high Tc BSCCO superconductors, typically embedded in a noble metal matrix (eg, Ag). Without limitation, 1G wires are manufactured by a thermomechanical process, in which the superconducting powder is packaged in silver billets that are stretched, laminated and heat treated to form the wire. The drawbacks of 1G wires are high material costs (eg, Ag), elaborate processing operations, and generally low critical current performance in high magnetic fields at high temperatures, which limit wire lengths.
[004] The processing of second generation HTS wires (hereinafter 2G) involves the deposition of thin film from a multilayer stack on nickel alloy tapes. In order to achieve high critical currents, the maximum current of a superconductor, the superconducting film is epitaxially grown in monocrystalline type in the oxide damping layers that provide a monocrystalline type template when deposited on polycrystalline metal substrate. In certain cases, 2G HTS tape uses conductors coated with YBCO.
[005] Recently, the focus of the HTS industry has been to increase the current carrying capacity, yarn production yield and decrease the manufacturing cost. The goal is to manufacture high-performance HTS wire that is available to the power industry to build devices, such as transmission cables and transformers, for the power grid. Recent prototypes have confirmed the great potential of HTS wire in electric power applications, but have also revealed deficiencies that present the risk of its widespread implementation.
[006] Although superconductors have zero resistance to DC current, the architecture of the coated conductor has yet to be optimized for AC applications, such as motors, generators and transformers. Hysteresis losses in the superconductor are the main component of AC losses and inversely correspond to the filament width. In particular, the ratio of width to thickness of the HTS wire is high, which causes conductors coated with HTS to present very high hysteresis losses. The magnitude of the losses also varies with the amplitude and frequency of the AC field and thus varies in different applications. AC losses on a typical HTS 2G wire with a copper stabilizer can be high up to 100 kW over 10 km in a perpendicular field of 100 mT at 60 Hz.
[007] A significant reduction in hysteresis losses in HTS wires is a prerequisite for its use in AC power applications, such as transformers, generators and motors. In practice, AC losses result and a higher cryogenic load and impose risk in electric power systems. To mitigate these risks, greater cooling capabilities or redundant cooling equipment have to be used, which greatly increase the overall cost of the system and are a significant impediment to the adoption of this immature technology. For these reasons, the development of a commercially viable high performance AC-tolerant HTS wire would be a transformational solution that would open up the application of superconducting products for electrical power systems.
[008] It is known that hysteresis losses can be reduced if the superconducting layer is divided into many filament-like superconducting structures, segregated by non-superconducting resistive barriers. Therefore, to minimize losses by AC hysteresis, it is desirable to subdivide the current-carrying HTS layer of a ribbon into long thin linear strips, or filaments, thereby forming a multifilament conductor. Although these multifilament conductors have been shown to greatly reduce hysteresis losses, numerous engineering and manufacturing challenges remain before the total commercialization of these HTS yarns because the large-scale adaptation of 2G multifilament HTS yarn for industrial manufacturing is fraught with numerous barriers.
[009] The method of making HTS 2G low loss AC wire is to subdivide superconducting and insulating material into multiple filaments by first depositing the superconducting layer and then attacking the superconducting layer (by physical or chemical techniques) to create streaks or continuous filaments. The use of a corrosive product inevitably results in damage to the superconducting material, such as edge curl, undercut and broken filaments. The filament damage becomes more prominent when the filament gap is narrow. More specifically, damage to the filament greatly reduces the current carrying capacity of the HTS wire. In addition, if the attack process is modified to avoid damage to the filament, bridges or other incomplete separations between the filaments can be left behind, which results in filament coupling and negates the reduction of AC loss. In fact, any superconducting residue that remains in the gaps after the attack can result in filamentary coupling. If the clearance is increased to avoid these problems, more superconducting material is removed, which greatly reduces the ability to carry wire current. Even at short lengths, such as one meter lengths, these HTS 2G multifilament yarns contain the flaws described here. As such, producing kilometer-long 2G HTS wires with thin filaments of continuous superconducting parallel lines, disposed from end to end, presents a technological barrier to adapt for large-scale use of HTS wires in electrical power systems.
[0010] As such, there is no commercially viable method for making an AC-tolerant HTS yarn by a non-attack process to produce multifilament HTS layers. Some techniques without attack have been proposed, such as creating scratches on the substrate before the growth of the superconductor (publication of US patent application No. 2007/0191202, by Foltyn et al), or inkjet printing of superconducting filaments (RC Duckworth , MP Paranthaman, MS Bhuiyan, FA List, and MJ Gouge, IEEE Trans. Appl. Supercond. 17, 3159 (2007)), or drop-by-drop deposition of superconducting material (Publication of US patent application No. 2006/0040829 , by Rupich et al). However, these techniques result in unintentional filament coupling that leads to reduced loss of deficient and inconsistent AC and tapes that cannot be used, even in lengths of one meter, also in lengths of kilometers. This points out that, in addition to providing a high degree of precision and control to produce a multifilament HTS yarn, any technique without attack has to be compatible with current HTS conductor manufacturing techniques, and it is also essential to control the flow distributions and current on the HTS tape. SUMMARY OF THE INVENTION
[0011] According to a first aspect of the present description, a high temperature superconducting structure is provided, comprising a substrate on which at least one damping layer is deposited, said substrate having a length and a width, the length of which is it is at least about 100 m and the substrate has a proportion of dimensions not less than about 103; a superconducting layer on said at least one damping layer, said layer comprised of superconducting material that forms at least two substantially parallel superconducting filaments that extend continuously along the length of said substrate; wherein the at least two superconducting filaments are separated from each other by at least one insulating strip with a first and second surface opposite to each other, said first surface overlapping said damping layer and said second surface being substantially free of said superconducting material; wherein the at least one insulating strip extends continuously along the length of said substrate and is comprised of insulating material with a resistivity greater than about 1 mΩcm.
[0012] According to another aspect of the description, a method is provided for producing a superconducting high temperature structure, comprising the steps of providing a damped substrate comprising a substrate and at least one damping layer; deposit on the damped substrate at least one insulating strip that extends continuously along the length of said damped substrate and is comprised of insulating material with a resistivity greater than about 1 mΩcm, such that the at least one insulating strip has a first and the second surface opposite to each other and said first surface is adjacent to said damped substrate; and depositing superconducting material on said damped substrate to form a superconducting layer comprised of at least two superconducting filaments that extend continuously along the length of said substrate, and which are separated from each other by at least one insulating strip and are substantially parallel, wherein the second surface of said insulating strip is substantially free of said superconducting material. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present description can be better understood by reference to the attached drawings.
[0014] Figure 1 illustrates an exemplary multifilament HTS structure according to the description.
[0015] Figure 2 illustrates a cross section of an exemplary embodiment of the present description.
[0016] Figure 3 illustrates a perspective view of a superconducting structure comprising superconducting filaments and alternating insulating strips, according to an exemplary embodiment of the present description.
[0017] Figures 4 A - E are illustrative drawings for a non-attack method of manufacturing a multifilament HTS structure according to an embodiment of the present description.
[0018] Figure 5 illustrates a flow chart of the steps that comprise a manufacturing process described here for an embodiment of the present description.
[0019] Figures 6A - B show photographs of the differential deposition of a coating material through an insulating strip and adjacent superconducting material according to an embodiment of the present description.
[0020] Figures 7A - B show a modality of the description used to test the resistance of the insulating strips to a current that passes perpendicularly through them, and the resistance data generated by it.
[0021] Figures 8A - B show how the microstructure affects the insulating material in the electrodeposition of a silver capping layer according to a modality of the description.
[0022] Figures 9A - B show a material outside the scope of the description and how the microstructure of the insulating material affects the electrodeposition of a silver cap layer according to a modality of the description.
[0023] Figure 10 shows a cross section of a tape consisting of the insulating strip and a material coated on a metal substrate according to one embodiment of the description.
[0024] The use of the same reference symbols in multiple parts of the drawings, different drawings, or in different modalities may indicate items similar or identical to those described here. Referring to drawings in general, it should be understood that the illustrations are not drawn to scale, and are intended to describe a particular modality of the present description and are not intended to limit the scope of the description to these. DETAILED DESCRIPTION OF THE INVENTION
[0025] REVIEW: The present description eliminates the filament attack process that was ubiquitously used to manufacture HTS 2G multifilament yarn. More specifically, this description is aimed at conductors coated with multi-strand HTS and the non-attack method of making the same. According to one embodiment of the description, the manufacture without attack of a multifilament AC-tolerant superconductor comprises the deposition of at least one insulating filament prior to the deposition of the superconducting material. According to another embodiment of the description, the manufacture without attack of a multifilament AC-tolerant superconductor comprises the deposition of the superconducting material before the deposition of at least one insulating filament and subsequent heat treatment.
[0026] MULTIFILAMENT HTS: Figure 1 shows a structure of multifilament HTS that is according to an exemplary embodiment of the present description. The embodiment shown in figure 1 shows an HTS conductor 200 comprising superconducting filaments 91 alternating with insulating strips 20. In the exemplary embodiment shown in figure 1, superconducting filaments 91 and insulating strips 20 are shown arranged parallel to the current flow direction 300 along of "wire" or "ribbon". Without being limited to any particular theory, the exemplary HTS conductor 200 may be suitable for increasing current carrying capacity and reducing resistive AC losses in HTS "wires or tapes".
[0027] In the form used herein, the terms "wire" and "ribbon" are used interchangeably to mean an HTS conductor with attributes that make it suitable for creating superconducting devices such as cables, transformers, generators, or power grids, or others means for transporting electrical energy from one location to another and distributing or otherwise delivering electrical energy to numerous locations, or devices. For example, the width of the ribbon or yarn can generally be on the order of about 0.01 cm to about 20 cm, alternatively, 0.1 cm to about 15 cm and, in certain cases, the width of the ribbon or yarn it can be between about 0.4 cm to about 10 cm and the length of the tape is typically at least about 100 m, more typically about 500 m, but it can still have a length of the order of about 1 km or more . The term "ribbon" or "ribbon type" refers to an article with a high proportion of dimensions, for example, a length-to-width ratio, of the order not less than about 102, alternatively, a proportion of dimensions not less than about of 103. Alternatively, the size ratio is greater than about 104 and, in additional cases, the article tape or yarn has a size ratio of about 105 or more. In the form used here, the expression "aspect ratio" is used to denote the ratio of the largest dimension of the article to the next largest dimension of the article, for example, the ratio of length to width.
[0028] Additionally, the article may have a thickness, the width to thickness ratio may be of the order not less than about 10, alternatively not less than about 102, in addition the ratio may be greater than about 103 and, in certain cases, the ribbon or wire article has a width to thickness ratio of about 105 or more. Without limitation by theory, in the form used here, an article with a large proportion of dimensions (for example, greater than 102) and a great width to thickness ratio (for example, greater than about 10) can be considered a "tape" or "ribbon type".
[0029] Figure 2 is a cross-sectional view of an HTS 200 conductor according to an embodiment of the present description with a multilayer composition. Also shown in figure 2 are insulating strips 20 overlapping the surface 61 of the substrate 60, positioned between the superconducting layers 90. According to the description, the conductor HTS 200 generally includes a substrate 60, at least one damping layer 50 overlapping the surface 61 of the substrate 60, a superconducting layer 90 overlapping the surface 51 of at least one damping layer 50. The superconducting layer 90 has a first stabilizing layer or capping layer 70 deposited thereon. According to another exemplary case of the present description, a second stabilizing layer 80 can be incorporated to overlay the superconducting layer 90 and, in particular, to overlap and make contact with capping layer 70. In certain cases, the second stabilizing layer 80 is in direct contact with the capping layer 70.
[0030] As shown in figure 3, according to the present description, the HTS 200 conductor additionally includes at least one insulating strip 20 and, alternatively, the HTS 200 conductor comprises a plurality of insulating strips 20. The insulating strips 20 can be filament-like structures or any other structure that extends continuously along the length of the HTS 200 conductor, as previously discussed. Insulating strips 20 are arranged substantially parallel to each other and substantially parallel to the current flow 300 within the conductor HTS 200.
[0031] At least one insulating strip 20 preferably extends along the entire length of the HTS conductor 200. For example, the length of the insulating strip 20 can be at least about 100 m, alternatively, about 500 m, and, in certain cases, the insulating strip 20 may be about 1 km or more in length. Without being limited to any theory, it can be understood that the insulating strip 20 will correspond to approximately the length of the HTS conductor 200. In an alternative embodiment, the insulating strips 20 are less than the length of the conductor 200. The width of the insulating strip 20 is typically in the range of about 1 micron to about 250 microns; alternatively, the width of the insulating strip is between about 10 microns and about 200 microns and, in certain cases, between about 15 microns and about 100 microns. In addition, in certain cases, the widths of the insulating strips 20 are selected to optimize the critical current density while still minimizing AC loss.
[0032] As shown in figures 1-3, in the exemplary embodiment, insulating strips 20 are deposited on the surface 51 of at least one damping layer 50. In certain cases, insulating strips 20 divide superconducting layer 90 into multiple superconducting filaments 91 , thus forming an array of superconducting filaments. Superconducting filaments 91 are comprised of superconducting material and, as insulating strips 20, superconducting filaments 91 continuously extend substantially parallel along the length of the HTS 200 conductor. The widths of filaments 91 are selected to optimize the critical current density, while minimizing the loss of AC, as skilled in the art can understand, without limitation.
[0033] Insulating strips 20 have substantially reduced superconductivity, or no superconductivity, in order to insulate superconducting filaments 91 and thereby reduce losses CHAMBER In certain cases, insulating strips 20 prevent electrical coupling of the superconducting filaments 91. At least one insulating strip 20 comprises material insulation that has high resistivity to electric currents to keep the superconducting filaments uncoupled. Examples of suitable insulating materials include, but are not limited to: materials based on magnesium, zinc, iron, molybdenum. In an exemplary embodiment of the description, the insulating material has a resistivity greater than about 1 milli-ohm centimeter (mΩ-cm). In addition, as is understood by those skilled in the art, any resistivity suitable for application is within the scope of the description without limitations. In certain cases, the insulating strip material 20 may be an oxide that does not form a superconducting material when subjected to a superconducting film coating process. In a non-limiting example, the insulating material may comprise a ceramic oxide such as magnesium oxide, or another oxide suitable for the application. In still other embodiments, the insulating material may be non-ceramic material that is not superconducting, is a weak conductor, and does not form a superconducting material when subjected to a superconducting film coating process.
[0034] In description modes, the HTS 200 driver has certain performance parameters. In exemplary embodiments, the HTS conductor comprises a critical current of at least 200 A / cm over a length of at least 10 meters at 77 degrees Kelvin (K) (-196 ° C). Furthermore, the HTS 200 conductor has an AC loss of less than about 1 W / m measured at 77 K (-196 ° C) in a 100 mT AC magnetic field and a frequency of 60 Hz applied perpendicular to the surface driver 200.
[0035] Figures 4A-4E are illustrative drawings showing the successive steps to manufacture a multifilament AC-tolerant conductor according to the present description. Non-limiting examples of materials and methods for depositing it are presented below. Referring to figure 4A, the HTS 200 conductor is manufactured first by depositing buffer 50 on substrate 60 to form the buffered substrate 100. Although this preliminary step is described in detail here, it should not be limiting, and it should be understood that any A method of producing damped substrate 100 generally known in the art or those skilled in the art can be used. In addition, the present description is not limited to the particular modes of damped substrate 100 described herein. Substrate 60 supports the HTS 200 conductor. Substrate 60 can be a metal, a polycrystalline ceramic, an alloy or modification thereof, or a combination thereof. In an exemplary embodiment, substrate 60 is a metal and, in certain cases, substrate 60 is an alloy of at least two metallic elements, such as, but without limitation, a Ni-based metal alloy. As those skilled in the art can see, the substrate material will vary according to the intended use of the superconducting article, and is not critical to the description. Substrate 60 can be manufactured using any suitable translation process, without limitation, such as reel-to-reel translation.
[0036] As previously revealed, the thickness of the substrate 60 will vary according to the application. However, substrate 60 is typically in a ribbon-like configuration, with a high proportion of dimensions. Substrate 60 can be treated so as to have desirable surface properties for subsequent deposition of the constituent layers of the HTS tape. For example, the surface can be slightly polished to a desired flatness and surface roughness. Additionally, the substrate can be treated so that it is biaxially textured. An exemplary process for forming a biaxially textured substrate is the RABiTS process or biaxially textured substrates assisted by lamination, as is known to those skilled in the art.
[0037] The cushion layer 50 is arranged on the surface 61 of the substrate 6. The cushion layer 50 can be a single layer or, alternatively, be made up of at least one additional film. In certain cases, the damping layer 50 includes any biaxially textured film suitable for the subsequent formation of an HTS layer. In certain cases, the damping layer 50 supports the HTS layer to have desirable crystallographic orientation for superior superconducting properties. Such biaxial texturing can be accomplished by ion beam assisted deposition (IBAD), as is known in the art, and as defined and described in U.S. Patent No. 6,190,752, which is incorporated by reference for all purposes. Without being limited to any theory, MgO is a material to form the IBAD film. In certain embodiments, the damping layer 50, for example, comprising IBAD film, without limitation, may range from about 50 Angstroms to about 500 Angstroms, alternatively from about 50 Angstroms to 200 Angstroms, and in additional cases of about 50 Angstroms to about 100 Angstroms. Although not specifically illustrated, the damping layer 50 may also include additional films to isolate substrate 60 from the epitaxial film or reduce mismatch in the lattice constants between the HTS layer and the epitaxial film. In certain cases, if the substrate 60 comprises a biaxially textured surface, the damping layer 50 can grow epitaxially on the textured substrate 60 in order to preserve the biaxial texturing in the damping layer 50, without limitation.
[0038] Referring to figure 4B, insulating strips 20 are deposited on the surface of the damped substrate 100. According to the present description, insulating strips 20 can be deposited either by chemical or physical deposition technique, through mask 110 in any a stationary or mobile damped substrate 100, or by printing techniques such as inkjet printing, screen printing and the like. Without limitation by theory, the insulating strips 20 can be any of the above and can be formed by any method known to those skilled in the art.
[0039] In an exemplary embodiment of the description, a method for depositing insulating strip would include the use of a mask 110. To deposit at least one insulating strip 20 on the surface of the damped substrate 100, the insulating material is deposited through the mask openings. 110 while the cushioned substrate 100 is moving below the mask 110. Preferably, the mask 110 is not in contact with the surface of the cushioned substrate 100, but instead it is in close proximity to the surface. Insulating material is deposited through the mask 110 in a deposition zone using, for example, magnetic sputtering as a deposition technique. Using this technique, the insulating material can be deposited at an operating pressure of less than about 1 millimeter. Without being limited to any theory, the lowest possible operating pressure can be used to provide insulating strips 20 with sharp sharp edges. The deposition of insulating strips through the mask 110 can also be carried out using other deposition processes known to those skilled in the art, without limitation.
[0040] A technique in which a mask 110 is physically attached to the surface of the damped substrate 100 before depositing the insulating material can also be used, followed by a step in which the mask 110 is lifted from the surface once the insulating strips 20 have been deposited. In addition, in certain cases, insulating strips 20 generally have a thickness in the range of about 0.5 to about 30 microns, more typically about 2 to about 20 microns, and preferably about 1 to about 10 microns , as previously disclosed here. As such, it can be understood that figure 4C illustrates cushioned substrate 100 with insulating strips 20 after the mask 110 has been removed.
[0041] Next, as shown in figure 4D, material is deposited on the damped substrate 100 to form superconducting layer 90. According to the present description, during deposition of superconducting layer 90, the material covers only surface 51 of the damped substrate 100 that is exposed. The material that lines the insulating strips 20 is of high resistivity, and has no superconducting properties. Only material on the substrate surface 51 between the insulating strips 20 is superconducting, thus resulting in a controlled filament of the HTS 200 conductor to create superconducting filaments and is illustrated as 91 in the subsequent figure 4E. The deposition of superconducting material on surface 51 between the insulating strips 20 prevents electrical coupling of the superconducting filaments 91. Decoupled or electrically disconnected superconducting filaments 91 are preferred in the present description in order to achieve the present benefits of a multifilament superconductor 200.
[0042] The process of this description can be practiced with any known HTS material. Although not critical to the practice of the description, superconducting layer 90 generally has a thickness in the range of about 1 to about 30 microns, more typically about 2 to about 20 microns, and preferably about 2 to about 10 microns in order to obtain desirable nominal voltages. Superconducting layer 90 can be chosen from any of the high temperature superconducting materials that have superconducting properties above the temperature of liquid nitrogen, 77 K (-196 ° C), and preferably a superconducting oxide. A class of materials includes REE ^ CusCUx, where RE is a rare earth element, such as Y, and related compounds. Such materials may also include, for example, BÍ2Sr2Ca2Cu30io + y, TÍ2Ba2Ca2Cu30io + y, and HgB2Ca2Cu30s + y. Of those exposed, YBa2Cu3θ7-x, also generally referred to as YBCO, can be used in certain cases. In addition, deposition of the superconducting layer 90 is carried out using any deposition process appropriate for the application known to those skilled in the art and, for example, both thick and thin film forming techniques can be employed, without limitation.
[0043] Without being limited to any theory, the superconducting material is preferably coated continuously on the surface 51 of the damped substrate 100, instead of insulating strips 20, this manufacturing technique provides certain benefits and ease of adapting large-scale production to large lengths. That is, because the superconducting material does not coat insulating strips 20 as a continuous film, it is not necessary to introduce polishing / etching steps such as those found in previous manufacturing methods to remove the superconducting material from the surface of insulating strips 20 and how discussed here. If it were necessary to do so, and not done, the coupling of superconducting filaments 91 in this way would not enjoy the benefit of creating a HTS 200 multifilament conductor disclosed here.
[0044] As shown in figure 4E, known electroplating techniques can be employed to deposit a first stabilizing layer, or capping layer 70, on the surface of superconducting filament 91, followed by the electroplating of a second stabilizing layer 80. The capping layer 70 and the second stabilizer layer 80 are generally implemented for electrical stabilization. More particularly, both the capping layer 70 and the second stabilizing layer 80 assist in the continued flow of electrical charges along the HTS 200 conductor in cases where cooling is unsuccessful or the critical current density is exceeded, and the superconducting filament 91 changes superconducting state and becomes resistive.
[0045] According to the present description, the resistivity of superconducting filaments 91 is orders of magnitude smaller than that of insulating strips 20. Therefore, the architecture of the HTS 200 tape, with alternating superconducting filaments, provides preferential electrodeposition of the cap 70 and stabilizer layer 80 only in superconducting filaments 91. The present description thus avoids any coupling of superconducting filaments and preserves the advantage of filamentation for lower AC losses. As can be understood, a noble metal can be used for the capping layer 70 to prevent unwanted interaction between the stabilizing layer 80 and the HTS 91 layer. Typical noble metals include gold, silver, platinum, palladium and combinations thereof, without limitation. In certain cases, silver can be used to reduce cost and improve overall accessibility. The capping layer 70 is preferably thin for cost reasons, but thick enough to prevent unwanted diffusion of the components from the stabilizing layer 80 to the HTS 91 layer. Typical thicknesses of the capping layer 70 range from about 0.1 micron to about 100 microns; in some cases, about 0.1 microns and about 10 microns; and in certain cases about 1.5 microns to about 3.0 microns, without limitation.
[0046] Referring again to figure 4E, the second stabilizing layer 80 can be deposited. The second stabilizer layer 80 is preferably copper and functions as a thick stabilizer. According to this description, electrochemical deposition techniques, such as galvanizing, can be used to completely coat and encapsulate conductor 200 with a suitable stabilizer to form the second stabilizer layer 80 in the exposed areas of the capping layer 70. In order to provide adequate current carrying capacity in the stabilizer layer, typically the second stabilizer layer 80 has a thickness in the range of about 1 to about 1,000 microns, more typically in the range of about 10 to about 400 microns, such as about from 10 to about 200 microns. Particular modalities had a nominal thickness in a range of about 20 microns to about 50 microns, without limitation.
[0047] According to a particular feature of the modality, a galvanizing technique defined and described in US publication No. 2006/0079403 (serial number 11 / 130.349), which is incorporated herein by reference, can be used to form the layer stabilizer 80. According to this technique, because the capping layer 70 is conductive, galvanization can be carried out at a high deposition rate, typically at a rate of about 1 micron per minute or more, to quickly constitute the layer thick stabilizer 80 on the superconducting tape. More particularly, the capping layer 70 functions as a seed layer for depositing copper, or other metal, on it. Although reference is generally made here to copper, it is noted that other metals, including aluminum, silver, gold, and other thermally and electrically conductive metals, can also be used as a secondary stabilizer to form the stabilizer layer 80. However, it is generally It is desirable to use a non-noble metal to reduce the overall cost of materials to form the superconducting tape. Although the particular example revealed here makes reference to standard galvanizing techniques, there is no particular limitation regarding the electrochemical deposition methods used. According to this description, the stabilizer layer 80 can overlap one of the two opposite main surfaces of the substrate, both main surfaces, or it can completely encapsulate the substrate, damping layer, and superconducting layer. However, because of the high resistivity of the insulating strip 20, it is not coated with the stabilizing layer. By leaving these insulating strips 20 uncoated, the coupling of superconducting filaments is prevented.
[0048] As previously described, a completely non-attack process is possible to manufacture a HTS 2G multifilament yarn that is robust and applicable to large lengths with a high yield. According to specific modalities of the description, HTS 200 tape comprises 400 pm wide 91 superconducting filaments and 100 pm wide 20 insulating strips 20. In this embodiment, about 20% of the superconducting cross section is not available for current flow. In order to maximize the current carrying capacity, the width of the insulating strips 20 is minimized. Therefore, in a preferred embodiment of the description, HTS 200 tape comprises 100 pm wide 91 superconducting filaments separated by 10 pm wide 20 insulating strips, which results in a reduction of AC loss by a factor of 40 with a reduction of only 10% in the passage of critical current. In additional modalities of the descriptions, a superconducting structure is created, which results in an even greater reduction in AC losses. For example, in one embodiment, ferromagnetic material is incorporated into the insulating strips 20 in order to further reduce AC losses. A flowchart of the individual steps that comprises a modality of the manufacturing process without unprecedented attack described above is illustrated in figure 5.
[0049] Figures 6A and B show photographs of the microstructure of a description modality. Specifically, figure 6A shows a 500X magnification of a portion of one embodiment of the description, specifically an insulating strip 20 with a superconducting layer 90 on each side, and associated transition layers 10. Figure 6B shows a 3,500X magnification of the same material, showing more details of the microstructure of the superconducting layer 90, insulating strip 20, and transition 10 between them. Clearly shown is the differential organization of the coating materials after deposition of the superconductor.
[0050] Figures 7A and B show the results of a resistivity test of a 201 ribbon mode of the description. Specifically, Figure 7A shows the alternating filamentary structure of tape 201 of the description, namely, a superconducting filament 91 alternating with an insulating strip 20. At a time without current conduction 300, varying amounts of voltage were applied to tape 201, or they passed through the tape 201, perpendicular to the direction that the filaments 91 are arranged and the current flow direction 300 during operation. The resulting amperage was measured on the revealed wires or tape 201, for example, in the current flow direction 600 illustrated by the arrow in 7A. Figure 7B shows a graph of resistivity data and shows that it was not observed that the insulating material 20 has any superconducting material that would carry a current even of only 10 nA, and the tape 201 had a resistance of approximately 54 mΩ.
[0051] Figures 8A and B show the microstructure of a coated material according to the scope of the description and how this structure affects the subsequent silver electrodeposition on the material. Figure 8A shows the microstructure of a coating material on an insulating strip made of magnesium oxide, and figure 8B shows the results of silver electroplating on the same material. It can be clearly seen that silver does not adhere to the highly resistant material coated on the insulating strips 20, while it adheres strongly to the superconducting portions 91 of the material.
[0052] Figures 9A and B show the microstructure of a coated material and how this structure affects the subsequent silver electrodeposition on the material. Specifically, figure 9A shows the microstructure of a coating material on an insulating strip 20 made of yttria, and figure 9B shows the results of silver electroplating on the same material. It is clear that silver adheres much more freely to all material, compared to the material shown in figure 8B. Because the yttrium-coated material has a low resistance, silver adheres to both the superconducting 91 and insulating 20 regions of the material, thus coupling the superconducting filaments and rendering the filament structure useless for reducing AC loss.
[0053] Figure 10 shows a cross section of a tape consisting of insulating strip 20 composed of magnesium oxide and a material coated on a metallic substrate 60. The transition region 10 adjacent to insulating strip 20 is also shown.
[0054] Referring now to figure 11, in an alternative embodiment of the present description, it can be understood that the insulating strips 20 are coated, not on the coated substrate 60 of the buffer 50, but, instead, in the superconducting layer 90 The same materials disclosed here that are used for insulating strip 20 on the damping substrate can be coated on superconducting layer 90 without limitation. In this alternative exemplary embodiment, after the deposition of the insulating strips 20 on the superconducting layer 90, the tape 400 is subjected to a thermal treatment to promote diffusion of the constituents of the insulating layer 20 to the superconducting layer 90 directly below. The temperature of a heat treatment like this can vary from about 300 ° C to about 900 ° C; alternatively, from about 400 ° C to about 700 ° C. In certain cases, the time for this heat treatment can vary from about 10 minutes to about 20 hours. As those skilled in the art can understand, the period of heat treatment may depend, at least partially, on the insulating material, the superconducting material and the control of the rate of temperature change to reach the heat treatment temperature. Without being limited to any theory, during this heat treatment, the superconducting film under the insulating strips is deleteriously affected, resulting in the conversion to a non-superconducting material 190.
[0055] The alternative method described above provides an additional method of producing an HTS 400 wire or ribbon structure illustrated in Figure 11. The superconducting filaments 90 are separated by non-superconducting material 190 according to this description. After heat treatment, a stabilizing layer 70 is deposited on the tape by a process such as electrodeposition, previously described herein. Since the insulating strips 20 above the non-superconducting 190 are highly resistive, silver will cover only the superconducting filaments 90, and not the insulating strips 20. Subsequent stabilizing coating 80, such as, but without limitation, thick copper, it can be deposited on tape 400 by a process such as electrodeposition, previously described here. Again, since the insulating strips 20 over the non-superconducting material 190 are highly resistive, copper will cover only the superconducting filaments covered with silver 90, and not the insulating strips 20. Consequently, even by this alternative modality, a superconductor of Multifilament 400 with completely ribbed stabilizers is created without involving any chemical attack.
[0056] As such, without being limited to any theory, the structure can comprise a series of layers, illustrated in figure 11. Referring again to figure 11, the cross sectional view of an HTS 400 conductor with a multilayer composition is shown . In some cases, the superconducting layer 90 is deposited on at least one damping layer 50. As described herein, the insulating strips 20 can be deposited on the superconducting layer 90 before heat treatment. After heat treatment, a non-superconducting material 190 is formed in superconducting layer 90. As such, and according to the description, conductor HTS 400 generally includes a substrate 60, at least one damping layer 50 overlapping the surface 61 of the substrate 60, a superconducting layer 90 overlapping the surface 51 of at least one damping layer 50. The superconducting layer 90 has a first stabilizing layer or capping layer 70 deposited thereon. According to another previously described embodiment of the present description, a second stabilizing layer 80 can also be incorporated, to overlay the superconducting layer 90 and, in particular, to overlap and make contact with the capping layer 70. In certain cases, the second stabilizing layer 80 is in direct contact with the capping layer 70.
[0057] Although the absence of chemical attack provides an advantage of the modalities disclosed herein, those skilled in the art can understand that at least one chemical attack step can be used to remove defective or superconducting microfilament defects, deposition defects, contamination and, generally , improve the multifilament structure and the manufacturing method disclosed in this invention. Those skilled in the art can see that a chemical attack step like this can be according to the scope of the description as a means of quality control, post-formation repair, or remanufacturing an HTS 200 conductor, without limitation. In addition, those skilled in the art will easily understand that the HTS 200 conductor can be incorporated into commercial power components, such as power cables, power transformers, power generators and power networks, without limitation, for a variety of applications and purposes.
[0058] At least one modality is revealed, and variations, combinations and / or modifications of the modality (s) and / or features of the modality (s) that can be made by those skilled in the art are within the scope of the description. Alternative modalities that result from the combination, integration and / or omission of resources of the modality (s) are also within the scope of the description. Where ranges or numerical limitations are expressly stated, such ranges or expressed limitations should be interpreted to include interactive ranges or limitations of a similar magnitude that fall within the ranges or limitations expressly stated (for example, from about 1 to about 10 includes, 2, 3, 4, etc .; greater than 0.10 includes 0.11, 0.12, 0.13, etc.). For example, whenever a numerical range with a lower limit, Ri, and an upper limit, Ru, is revealed, any number that falls in the range is specifically revealed. In particular, the following numbers in the range are specifically revealed: R = R | + k * (Ru-Ri), where k is a variable ranging from 1 percent to 100 percent, with an increment of 1 percent, that is, k is 1 percent, 2 percent, 3 percent, 4 percent, 5 percent , 50 percent, 51 percent, 52 percent ... 95 percent, 96 percent, 97 percent, 98 percent, 99 percent, or 100 percent. In addition, any numerical range defined by previously defined R numbers is also specifically revealed. The use of broader terms such as "comprises", "includes", and "has" should be understood in order to support more restricted terms such as "consisting of," consisting essentially of and "understood substantially from. , the scope of protection is not limited by the description presented here, but is defined by the following claims, that scope including all equivalents of the subject matter of the claims, each and every claim is incorporated as an additional description in the specification, and the claims are embodiments of this The discussion of a reference in the description is not an admission that it is prior art, especially any reference that has a publication date after the priority date of this application The description of all patents, patent applications and publications cited in the description are hereby incorporated by reference, to the extent that they provide exemplary details, procedures such or other supplementary details for the description.

权利要求:
Claims (19)
[0001]
1. Superconducting structure (200), characterized by the fact that it comprises: a substrate (60) on which at least one damping layer (50) is deposited, said substrate having a length and width, in which the substrate has a proportion of dimensions not less than about 102; a superconducting layer (90) in said at least one damping layer (50), wherein said superconducting layer (90) comprises a superconducting material that forms at least two substantially parallel superconducting filaments (91) which extend continuously along the length of said substrate; and in which a non-superconducting region (190) is formed between at least two parallel superconducting filaments (91), and in which at least one insulating strip (20) is arranged in the non-superconducting region (190); wherein the at least one insulating strip (20) has a first and a second opposite surface, said first surface overlapping said non-superconducting region (190) and said second surface being substantially free of said superconducting layer (90) ; wherein said at least one insulating strip (20) extends continuously along the length of said substrate (60) and is comprised of insulating material with a resistivity greater than 1 mΩcm; and a first stabilizing layer (70) overlapping the superconducting layer (90), where the insulating strip (20) is not coated with the first stabilizing layer (70), and where the at least two superconducting filaments (91) are not coupled.
[0002]
2. Structure according to claim 1, characterized by the fact that the at least two superconducting filaments (91) are decoupled by the exclusion of the heat treatment material.
[0003]
3. Structure according to claim 1, characterized by the fact that at least two superconducting filaments (91) have at least one property selected from the group consisting of: a critical current of at least 200 A / cm over a length of at least at least 10 meters, a width of at least about 50 pm, and a length of at least 100 meters.
[0004]
4. Structure according to claim 1, characterized by the fact that the insulating material comprises ferromagnetic material and a ceramic oxide selected from the group consisting of magnesium oxide, iron oxide, molybdenum oxide, manganese oxide, zinc oxide, chromium oxide, silicon oxide, and combinations thereof.
[0005]
5. Structure according to claim 1, characterized by the fact that said at least one insulating strip has a thickness in the range of 0.5 to 30 microns and a width in the range of 1 micron to 250 microns.
[0006]
6. Structure according to claim 1, characterized by the fact that the first stabilizing layer (70) comprises a noble metal overlapping the superconducting layer (90); and wherein the first stabilizer layer (70) has a thickness within the range of 0.1 microns to 10.0 microns and extends to define first and second side surfaces that encapsulate the structure.
[0007]
Structure according to claim 6, characterized in that it additionally comprises a second stabilizing layer (80) comprising an electrogalvanized non-noble metal selected from the group consisting of copper, aluminum, and alloys thereof; and that the second stabilizing layer has a thickness within the range of 1 micron to 1,000 microns.
[0008]
8. Structure according to claim 6 or 7, characterized by the fact that the structure has an AC loss of less than 1 W / m measured at 77 K (-196 ° C) in a 100 mT AC magnetic field and a frequency of 60 Hz applied perpendicular to a surface of said structure.
[0009]
9. Structure according to claim 1, characterized by the fact that said superconducting layer (90) comprises REBa ^ CuaO . x, where RE is a rare earth element.
[0010]
10. Structure according to claim 9, characterized by the fact that the superconducting layer (90) is selected from the group comprising YBaoCusCE-x, BioSioCa ^ CusOio + y, TÍ2Ba2Ca2Cu30io + y, HgBa2Ca2Cu3θ8 + ye combinations thereof.
[0011]
11. Structure according to claim 1, characterized by the fact that said multifilament superconducting layer comprises a high temperature superconducting material, with a critical temperature Tc not less than 77 K (-196 ° C).
[0012]
Structure according to claim 1 or 11, characterized in that the damping layer (50) comprises a biaxially crystalline textured film with crystals generally aligned both on and off the film plane.
[0013]
13. Method for producing a superconducting structure (200), characterized by the fact that it comprises: providing a damped substrate (100) comprising a substrate (60) and at least one damping layer (50); depositing superconducting material on said damped substrate to form a superconducting layer (90); deposit on the superconducting layer (90) at least one insulating strip (20) which extends continuously along the length of said damped substrate and is comprised of insulating material with a resistivity greater than 1 mΩcm, so that at least one insulating strip (20) has a first and second surface opposite to each other and said first surface is adjacent to said superconducting layer (90); and wherein the second surface of said insulating strip (20) is free of the superconducting material; heat treating at least one insulating strip (20) in the superconducting material to provide a non-superconducting region (190) below the first surface of at least one insulating strip (20) resulting in the superconducting layer (90) having at least two superconducting filaments ( 91) formed therein, the at least two superconducting filaments (91) extend continuously along the length of said substrate, are parallel and are separated from each other by the non-superconducting region (190); and depositing a first stabilizing layer (70) superimposed on the superconducting material, wherein the first stabilizing layer (70) is arranged only on at least two superconducting filaments (91).
[0014]
14. Method according to claim 13, characterized by the fact that the high temperature superconductor is capable of operation with an AC loss of less than 1 W / m, measured at 77 K (-196 ° C) in a magnetic field of 100 mT AC and a frequency of 60 Hz applied perpendicular to a surface of said structure.
[0015]
Method according to claim 13 or 14, characterized in that depositing the superconducting material on said damped substrate to form the superconducting layer (90) comprises depositing a layer of REBa ^ CuaCh-x, where RE is an element rare earth.
[0016]
16. Method according to any one of claims 13 to 15, characterized in that the superconducting layer (90) is selected from the group comprising YBa2Cu3θ7-x, BÍ2SÍ2Ca2Cu30io + y, TÍ2Ba2Ca2Cu30io + y, HgBa2Ca2Cu30s + y and combinations of the same.
[0017]
17. Method according to claim 13, characterized in that said at least one insulating strip (20) is deposited by a process selected from the group consisting of deposition through a mask, inkjet printing, screen printing, stamping, patterning and combinations thereof.
[0018]
18. Method according to claim 13 or 17, characterized by the fact that the process for deposition through a mask is selected from the group consisting of sputtering, chemical vapor deposition, sol-gel coating, evaporation and deposition by laser ablation.
[0019]
19. Method according to claim 13, characterized in that said superconducting layer (90) is deposited by a process selected from the group consisting of evaporation, sputtering, chemical vapor deposition, coating and cooking with centrifugation, deposition pulsed laser, cathodic arc deposition, plasma-enhanced chemical vapor deposition, molecular beam epitaxy, a sol-gel process, liquid phase epitaxy and combinations thereof.

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法律状态:
2018-12-26| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|

2019-10-22| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|

2020-04-07| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|

2020-10-20| B16A| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]|Free format text: PRAZO DE VALIDADE: 20 (VINTE) ANOS CONTADOS A PARTIR DE 22/06/2011, OBSERVADAS AS CONDICOES LEGAIS. |

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US35836910P| true| 2010-06-24|2010-06-24|

US61/358,369|2010-06-24|

PCT/US2011/041422|WO2011163343A2|2010-06-24|2011-06-22|Multifilament superconductor having reduced ac losses and method for forming the same|

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