Abstract: High T.sub.c superconductor quantum interferometric devices are disclosed. Such devices are especially suited for detecting small changes and spatial variation in magnetic field. Such detection finds important application in NDE evaluation of metals, in the evaulation of magnetic susceptibilities and in magnetic resonance spectrometers.

Abstract: An electrically conductive article is disclosed comprised of a support, a barrier and a heavy pnictide mixed alkaline earth copper oxide crystalline coating. The support is an austenitic metal alloy of chromium and one or more group VIII period 4 metals, and the barrier is comprised of a zirconia layer containing fissures and an oxide compatible with the electrically conductive crystalline layer located in the fissures.

Abstract: Articles are disclosed in which an electrically conductive layer on a substrate exhibits a superconducting transition temperature in excess of 30.degree. K. Conductive layers are disclosed comprised of a crystalline rare earth alkaline earth copper oxide. Processes of preparing these articles are disclosed in which a mixed metal oxide precursor composition is coated and heated to its thermal decomposition temperature to create an amorphous mixed metal oxide layer. The amorphous layer is then heated to its crystallization temperature.

Abstract: A laminated film comprising a thin film of single crystal YBa.sub.2 Cu.sub.3 O.sub.7-x having the (001) plane in the direction parallel with the film surface and a continuous insulating ultrathin layer of MgO which is formed on said superconductor film and has a thickness of not larger than 10.ANG. and the (001) plane in a direction parallel with the film surface is provided.

Abstract: A now superconducting material comprising a compound oxide represented by the general formula:(Sr,.gamma.).sub.x (La,.delta.).sub.1-x .epsilon..sub.y Cu.sub.1-y O.sub.3-zin which".gamma." represents an element of IIa group of the periodic table except Sr, an atomic ratio of .gamma. to Sr being selected in a range between 1% and 90%,".delta." represents an element of IIIa group of the periodic except La, an atomic ratio of .delta. to La is selected in a range between 1% and 90%,".epsilon." represents a metal element of Vb group of the periodic table, x, y and z are numbers each satisfies ranges of 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, and 0.ltoreq.z<1 respectively, andthe expression of (Sr,.gamma.) and (La,.delta.) mean that the respective elements position predetermined sites in a crystal in a predetermined proportion.

Abstract: A superconducting film is disclosed which consists of a rare earth alkaline earth copper oxide having an R.sub.1 A.sub.2 C.sub.3 crystalline phase over an R.sub.2 A.sub.1 C.sub.1 crystalline phase.

Abstract: A superconducting laminate having at least one layer of metal and at least one layer of superconducting material. The metal layer and the superconducting layer are bonded. The metal later may also include carbon fibers from various precursors. The superconductor may be a composite material. The invention also includes a method of making the laminates.

Abstract: A single crystal oxide superconductor and the method of producing the same. One face of a substrate is coated with an oxide superconductor for forming an oxide superconductor layer. Then, the oxide superconductor layer is heated so that the oxide superconductor has a single crystalline structure.

Abstract: Fibers of Bi(2212) have been produce by pendant drop melt extraction. This technique involves the end of a rod of Bi(2212) melted with a hydrogen-oxygen torch, followed by lowering onto the edge of a spinning wheel. The fibers are up to 15 cm in length with the usual lateral dimensions, ranging from 20 um to 30 um. The fibers require a heat treatment to make them superconducting.

Abstract: The present invention provides a method for joining of high-temperature oxide superconductors per se or a high-temperature oxide superconductor and other conductive material through a very simple process. According to this method, the joining is carried out by using an alloy comprising 0.1%-90% by weight of at least one divalent metallic element and the balance as a brazing material and heating and melting the brazing material. The resulting joined body has a joint low in resistance. The divalent metallic element of the alloy is preferably an element of Group IIA or IIB of the Periodic Table or a transition metal.

Abstract: A substrate for supporting a ceramic superconductor comprises a metallic base member having a constituent oxide former which establishes an oxide layer on the surface of the substrate. A layer of ceramic superconducting material covers the substrate with the oxide layer between the metallic base member and the ceramic superconductor layer to inhibit the interdiffusion of respective constituent elements between the metallic base member and the ceramic layer. For applications requiring the transmission of electrical current through the ceramic layer over relatively extensive distances, the substrate can be formed as a wire.

Abstract: A pipe comprises a hollow support member made from a member selected from copper and copper compounds and a copper oxide superconducting ceramic material which covers the inner surface of the support member with a space kept in the pipe for use in a magnet or power accumulator device.

Abstract: Articles are disclosed in which an electrically conductive layer on a substrate exhibits a superconducting transistion temperature in excess of 90.degree. K. Conductive layers are disclosed comprised of a crystalline heavy pnictide mixed alkaline earth copper oxide. Processes of preparing these articles are disclosed in which a mixed oxide precursor composition is coated and heated to its thermal decomposition temperature to create an amorphous mixed metal oxide layer. The amorphous layer is then heated to its crystallization temperature.

Abstract: Continuous malleable superconductive material which can be machined, rolled and soldered, being the product of sintering at an elevated temperature and pressure of a metal plated powder of a compound QBa.sub.2 Cu.sub.3 O.sub.7-x wherein Q is yttrium or europium, where x is smaller than one. The metal is advantageously silver and the plating process is one without the use of electricity. A preferred range of silver content is about 5 to 32 weight per cent, and the silver forms an essentially continuous phase in the superconductive material. Sintering can be done at from about 350.degree. and 950.degree. C., with a preferred range of 400.degree. to 900.degree. C. The superconductive material of the invention exhibits transition to zero-resisitivity state and the Meissner effect.

Abstract: Superconducting Ba--Y--Cu--O ceramic thin film is epitaxially deposited on a crystal substrate of LaAlO.sub.3, LaGaO.sub.3, PrGaO.sub.3 and NdGaO.sub.3.

Abstract: Improvement in a superconducting thin film of compound oxide represented by the formula: LnBa.sub.2 Cu.sub.3 O.sub.7- .delta. (Ln is lanthanide) or (La.sub.1-x .alpha..sub.x).sub.2 CuO.sub.4 (.alpha. is Ba or Sr) deposited on a substrate or core made of MgO, SrTiO.sub.3 or ZrO.sub.2 by physical vapor deposition technique, the surface roughness R.sub.max (datum length=1,000 .mu.m) of the superconducting thin film being less than 0.2 .mu.m.

Abstract: A superconducting wire and a process for fabricating such a wire. The present invention relates specifically to the fabrication of a wire using a ceramic superconducting material. Initially, a quantity of highly pure high temperature superconducting material is obtained. The superconducting material may be fabricated by any one of a number of known fabrication methods such as by aqueous coprecipitation, conventional sol gel techniques or solid state reaction processes.Once a ceramic superconducting material in particulate form is obtained, surface impurities on the particles are removed. One such surface cleaning procedure is known as "sputtering." Sputtering strips the surface atoms from the surface of the superconducting material, leaving only pure superconducting ceramic.The superconductive ceramic produced according to the procedure outlined above is then used in the formation of a superconducting wire.

Abstract: New Method of buffering silicon and similar semiconductor wafers with appropriate metal oxide layers which, in turn, have been found to be excellent substrates for MOS depositions without interaction with the semiconductor surface, and novel buffered wafers produced thereby.

Abstract: Disclosed is a method of preparing a superconductor wherein a precursor oxide mixture is dispersed in an appropriate polymer matrix and shaped into a predetermined form following which the matrix and oxide precursor are respectively carbonized and sintered simultaneously. An alternate method is to separately prepare a superconducting material from the precursor oxide mixture, grind the superconducting material and add it to a solution containing polyacrylonitrile, shape into a predetermined form, following which the superconducting material and matrix are, respectively, carbonized and then annealed.

Abstract: In a superconducting contact structure between an oxide superconductor and a metal superconductor, the oxide superconductor has a recess in a surface which is in contact with the metal superconductor.

Abstract: The structure of a wiring according to the present invention has a buffer layer interposed between an insulating layer and a wiring of a superconductive ceramic material, and the buffer layer hardly reacts on the superconductive ceramic material in a high temperature ambient, so that the superconductive ceramic material does not lose the superconductivity due to an influence of the buffer layer on the superconductive ceramic material during the formation stage of the wiring.

Abstract: A circuit element is disclosed comprised of a substrate and an electrically conductive layer located on the substrate. The electrically conductive layer is comprised of a crystalline rare earth alkaline earth copper oxide. The substrate is formed of a material which increases the electrical resistance of the conductive layer when in contact with the rare earth alkaline earth copper oxide during crystallization of the latter to an electrically conductive form. A barrier layer is interposed between the electrically conductive layer and the substrate. The barrier layer contains magnesium, a group IVA metal, or a platinum group metal, either in an elemental state or in the form of an oxide or silicide.

Abstract: A method for preparing a highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material to improve its critical current density. A film about 5-200 .mu.m thick of bismuth strontium calcium copper oxide is deposited on a suitable substrate. The ratios of Bi:(Sr, Ca):Cu in the film are about 2:3:2 to 2:4:3. A laser beam is translated over the deposited film at a rate of about 0.2-15 cm/hr while the film is held at a temperature of about 500.degree.-950.degree. C. The beam is about 0.01-0.50 cm wide along the direction of translation, and provides about 0.2-10W of optical power to the film. The temperature and the beam translation rate, width, and optical power are selected to permit zone melting and resolidification of the film to form the highly aligned thick film of superconducting bismuth strontium calcium copper oxide ceramic material. The J.sub.c may, if desired, be further improved by annealing the resolidified film at about 900.degree.-965.degree. C.

Abstract: A method for manufacturing a hard-to-work alloy article comprises the steps of: preparing a laminate member comprising a plurality of layers of different metals in a stoichiometric ratio for the intended alloy composition; dividing the laminate member into pieces; combining the pieces to a body for plastic deformation; subjecting the body to plastic deformation under pressure to form an article having a given shape and dimensions; and applying a thermal diffusion treatment to the article.

Abstract: A ceramic superconductor comprises a substantially nonmagnetic preannealed nickel-based alloy substrate which supports a ceramic superconductor. The substrate may include aluminum to strengthen the substrate and make it less magnetic. The substrate is substantially devoid of minority constitutent oxide shell formers and the ceramic is formed on the substrate by sintering superconductor grains at temperatures above 1000.degree. C. to enhance densification of the ceramic.

Abstract: Ceramic superconductor materials, e.g., of rare earth/alkaline earth metal/transition metal/oxygen type, contain an effective stabilizing amount of fluorine atoms distributed therein in a concentration gradient decreasing from the external face surface of the material to the core region thereof; advantageously the fluorine atoms are principally distributed in an external protective diffusion barrier layer.

Abstract: Disclosed herein is a multifilament superconducting wire of Nb.sub.3 Al comprising a core part of copper or copper alloy which is provided in a central portion as a stabilizing material and a peripheral part which is provided around the core part and formed by an Nb.sub.3 Al filament embedded in a matrix of copper or copper alloy, such that the ratio of copper or copper alloy forming the core part and the peripheral part to the Nb.sub.3 Al filament is at least 1 and not more than 5 in sectional area ratio and the diameter of the core part is at least 1/5 of the wire diameter.

Abstract: An Ytrium Barium Copper Oxide-based thick-film paste is disclosed, which when deposited on an alumina substrate is superconducting above the termperature of liquid nitrogen and substantially free of mechanical defects such as cracking or peeling. A method of applying the paste, including the curing process, insures that the YBC superconductor is boned to the substrate.

Abstract: A flexible Nb-containing superconductor-laminated aromatic polyimide material useful for superconducting wires and circuits, comprising an Nb-containing superconductor layer formed on an aromatic imide polymer substrate, which preferably comprise a polymerization-imidization product of an aromatic tetracarboxylic acid component comprising, as a major ingredient, a biphenyltetracarboxylic dianhydride with an aromatic diamine component comprising, as a major ingredient, an aromatic diamine having a one benzene ring structure.

Abstract: A combination is disclosed comprising a superconductive ceramic oxide which degrades in conductivity upon contact of ambient air with its surface and, interposed between said ceramic oxide surface and ambient air, a passivant polymer.

Abstract: Improvement in a superconducting thin film of a superconducting compound oxide containing thallium (T1) deposited on a substrate, characterized in that the superconducting thin film is deposited on {110} plane of a single crystal of magnesium oxide (MgO).

Abstract: Superconducting structure are composed of thin film of Ba-Y-Cu-O superconductor epitaxially deposited on a crystal substrate of SrLaAlO, SrLaGaO.sub.4, SrPrGaO.sub.4, SrNdGaO.sub.4, SrSmGaO.sub.4, SrEuGaO.sub.4, CaLaGaO.sub.4, CaPrGaO.sub.4, or CaNdGaO.sub.4.

Abstract: Improvement in a superconducting thin film of a superconducting compound oxide containing bismuth (Bi) deposited on a substrate, characterized in that the superconducting thin film is deposited on {110} plane of a single crystal of magnesium oxide (MgO).

Abstract: A composite member is prepared which comprises a core which will have a compound superconducting layer when heat-treated, and a stock for forming a stabilizing member made of copper and surrounding the core. The composite member is heat-treated in an oxidizing atmosphere, thus forming a copper-oxide thin layer on the surface of the stock. Thereafter, the composite member is heat-treated in a non-oxidizing atmosphere or in an atmosphere having an oxygen partial pressure which is too low to allow the forming of copper oxide. As a result, a compound superconducting wire is made which comprises a member including a compound superconductor, a diffusion-preventing layer made of oxide and surrounding the member, and a stabilizing member made of copper and surrounding the layer.

Abstract: This invention is a superconductor having a generally substoichiometric oxygen, nickel oxide insulation between superconduction strands. The superconductor is to have an operating temperature below 250 degrees kelvin, and has multiple superconductors, with a cladding of nickel on the strands, and an adherent coating of nickel oxide formed on the outer surface of the cladding. The nickel oxide has stoichiometric or less than stoichiometric oxygen (but not greater than stoichiometric oxygen) to be electrically insulating at the operating temperature of the superconductor. Thus high thermal conductivity strand insulation capable of withstanding strand to strand voltages of greater than 50 volts is provided to substantially eliminate coupling currents between the strands, and nickel oxide having areas of semiconducting due to containing more than stoichiometric oxygen is avoided.

Abstract: A method for manufacturing a stress controlled wire comprises the step of twisting superconductor fibers together into a bundle of fibers. A plurality of bundles are then twisted together and disposed within the lumen of a tube and the lumen is flooded with solder which is allowed to harden. The tube and its contents are subsequently heated as they are wound upon a drum to melt the solder and allow realignment of the superconductor fibers within the solder. The subsequent solidification of solder after the tube is wound onto the drum provides an unstressed support for the fiber bundles.

Abstract: A flexible electrically conductive article is disclosed comprised of an organic film, a conductive crystalline cuprate layer, and a release layer that together form a flexible electrically conductive assembly. The article is prepared by forming a conductive cuprate layer on a refractory substrate with the release interposed. After the cuprate layer is formed, the organic film is bonded to it, permitting the cuprate layer to be stripped intact from the substrate with the organic film. A crystal growth accelerating agent can be associated with the cuprate layer during its formation to minimize the heat energy required for crystallization.

Abstract: The invention relates to a process for producing superconductive ceramics wherein, first, a liquid alloy melt is made of metals; this is carried out at a temperature at which the melt is chemically homogeneous. The melt is subsequently atomized with an inert gas or with oxygen. In the first case, a powder develops which is oxidized in a further step whereas in the second case the oxide powder is a direct result. By means of sintering, for example, the oxide powder can be pressed to superconductive bodies of any desired form.

Abstract: A method for contraction annealing niobium-tin wire is disclosed. An improved niobium-tin wire is provided by loosely winding the wire on a mandrel, or by coiling the wire on a circumferentially retractile mandrel, and contraction annealing the wire without reaction-forming substantial amounts of Nb.sub.3 Sn. Such contraction annealing allows the wire to contract in length unconstrained thereby preventing the formation of internal tensile stresses in the wire and its surrounding insulation. Prevention of internal stresses in the wire greatly reduces the susceptibility of the wire to breakage, cracking, sintering, shorting, tin leakage, or substantial shifting of the wire from desired wrap positions when it is reaction annealed to form the brittle superconducting intermetallic compound Nb.sub.3 Sn.

Abstract: An extruded superconductor (1) comprises a conductor core composed of thin metal filaments, for example of niobium-titanium or niobium-tin, and a high-purity aluminium sheath (2) which acts as a stabilizer. A marked reduction in the electrical conductivity perpendicular to the longitudinal axis of the conductor is achieved by means of structures (3) in the form of cross-sectionally distributed layers, ribbon-like strips or closely aligned longitudinal single filaments or fibres or bundles of fibres made of a material of low conductivity embedded coaxially in the aluminium sheath. The layers of low conductivity material embedded coaxially in the aluminium sheath may be closed concentric circular sheaths surrounding the conductor core, at a distance from the core and from one another or ribbon-like strips made of the low conductivity material arranged in a star-shaped configuration about the conductor core.

Abstract: A superconducting wire comprises a wire element wherein a plurality of superconducting filaments are arranged in a metallic matrix, and a covering layer which is formed on the surface of the wire element with a number of filaments and has a laminated structure including at least one insulator film as the lower layer and at least one thermal conductor film as the upper layer. Frictional heat generated on the surface of the superconducting wire is prevented from being conducted to superconducting filaments by virtue of the presence of the insulator film, and is conducted through the thermal conductor film to be dissipated. Therefore, the temperature of the superconducting filaments is hardly raised.

Abstract: Superconducting composites are made from ceramic-type superconductors coated onto a low resistivity carbon fiber selected from those high strength fibers which have an ultrahigh modulus and high thermal conductivity. Flexible conductors of several different structures made from such composites are described as well as other useful forms of the composites.

Abstract: A method is disclosed for fabricating a wire from niobium tin produced in situ in a filamentous structure capable of achieving the superconducting state which comprises overlapping a tin alloy core comprised of tin-magnesium eutectic alloy with alternating layers of copper and foraminous layers followed by drawing the thus-formed niobium filaments into wire, then heating the wire at sufficiently high temperature to cause the eutectic alloy to homogeneously diffuse through the length of the copper wire and rods to react with the Nb, forming the A-15 crystal structure of Nb.sub.3 Sn, characterized by refined grain structure therein and improved current carrying capability.

Abstract: The process for preparing a precursor Nb.sub.3 Sn superconductor wire first assembling a billet comprising Nb rods surrounded by Cu material. A barrier material such as Nb is placed around the Cu and an outer stabilizer tube encases the billet. The billet is then preferably hot compacted after which it is extruded at an elevated temperature. A Sn rod is placed in the center of the billet and the entire composite is then drawn and twisted to the final size desired.

Abstract: Fibers of YBa.sub.2 Cu.sub.3 O.sub.x have been produce by pendant drop melt extraction. This technique involves the end of a rod of YBa.sub.2 Cu.sub.3 O.sub.x melted with a hydrogen-oxygen torch, followed by lowering onto the edge of a spinning wheel. The fibers are up to 10 cm in length with the usual lateral dimensions, ranging from 20 .mu.m to 125 .mu.m. The fibers require a heat treatment to make them superconducting.

Abstract: An oxide superconductor including an oxide superconductor member and a hermetical seal layer, coated over the oxide superconductor member, for hermetically sealing the oxide superconductor member from the atmosphere.

Abstract: A superconductive ceramic thin film-formed single-crystal wafer comprising a single-crystal wafer, an intermediate ceramic thin film formed on a surface of the single-crystal wafer, and a superconductive ceramic thin film formed on the intermediate ceramic thin film. The intermediate ceramic thin film comprises, as a main phase, a crystalline phase having a composition by atomic ratio of Bi.sub.2 Sr.sub.2 Ca.sub.x O.sub.y (provided that x: 1 to 2; and y: 6 to 7), and the superconductive ceramic thin film comprises, as a main phase, a crystalline phase having a composition by atomic ratio selected from the group consisting of Bi.sub.2 Sr.sub.2 Ca.sub.1 Cu.sub.2 O.sub.8 and Bi.sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10. Alternatively, the intermediate ceramic thin film comprises, as a main phase, a crystalline phase having a composition by atomic ratio selected from the group consisting of Tl.sub.1 Ba.sub.2 Ca.sub.s O.sub.t (provided that s: 1 to 2; and t: 4.5 to 5.5) and Tl.sub.2 Ba.sub.2 Ca.sub.v O.sub.

Abstract: The present invention relates to a method of directly forming a thin, oriented layer, or film, of superconducting materials, or compositions suitably mixtures of Perovskite-type superconducting oxides, on a support base, or substrate, by the use of a laser assisted molecular beam epitaxy. The method steps generally comprise forming at least one target comprised of metallic precursors of a superconducting oxide composition and vaporizing at least a portion of the target using a vaporization laser beam to produce a vaporized precursor of an appropriate or desired entrained in a pulsed, rapidly flowing, gaseous atmosphere containing at least one gas reactive with said vaporized precursor composition to form a reacted precursor of a superconducting composition. The reacted precursor composition is then formed into a substantially singular, uniform molecular beam, and deposited on a substrate in the form of a thin layer.

Abstract: A CaF.sub.2 passivation layer is applied on the surface of a superconducting oxide by evaporation which does not disrupt the superconductive properties of the superconducting oxide.

Abstract: A superconducting coil comprising a support (1,10) and at least one ring-shaped and/or spiral turn (2) of superconductor which is composed of superconducting compound oxide and is supported on a surface of said support.