Abstract: The present invention provides a high-throughput system for the ex-situ formation of a superconducting thin film, such as rare-earth-barium-copper-oxide (REBCO), atop a continuous length of buffered metal substrate tape by heating a buffered metal substrate tape coated with precursors of REBCO These precursors, when heated and introduced to water vapor within a process chamber, decompose to form a functional superconducting thin film epitaxial to the buffer layer. A chamber such as a metalorganic chemical vapor deposition (MOCVD) reactor having showerhead and substrate heater assemblies designed for the creation of a long and wide deposition zone is well suited for use in the process the system. The chamber could be of cold-wall type where the walls are not heated or could of hot-wall type where the walls are heated.

Abstract: Superconductor wires or layers having improved properties and methods for making the same are described. The superconducting layer includes a rare earth element-alkaline earth element-transition metal oxide having an average stacking fault density that is greater than about 0.01 nm?1, wherein two or more rare earth cations form the rare earth element. To form the superconductor layer of the present invention, a layer having a rare earth element-alkaline earth element-transition metal oxide substantially in a first crystal structure can be provided to a substrate where two or more rare earth cations form the rare earth element. The layer can then be heated at a temperature that is greater than 550° C. under oxidizing conditions to form a high-temperature superconducting layer substantially in a second crystal structure.

Abstract: A class of superconductive materials containing copper-oxygen bonding and with mixed cation-occupancy designed with a view to size and valence consideration yield useful values of critical temperature and other properties. Uses entail all applications which involves superconducting materials such as magnets and transmission lines which require continuous superconductivity paths as well as detectors (e.g., which may rely on tunneling).

Abstract: A method for maximising critical current density (Jc) of high temperature superconducting cuprate materials (HTSC) which comprises controlling the doping state or hole concentration of the materials to be higher than the doping state or hole concentration of the material that provides a maximum superconducting transition temperature (Tc), and to lie at about a value where the normal-state pseudogap reduces to a minimum. Jc is maximised1 at hole concentration p≈0.19. HTSC compounds are also claimed.

Abstract: A method is described to prepare a highly textured oxide superconductor article in a single deformation-sinter process. A precursor article including a plurality of filaments comprising a precursor oxide having a dominant amount of a tetragonal BSCCO 2212 phase and a constraining member substantially surrounding each of the filaments is provided. Each of the filaments extends along the length of the article. The oxide article is subjected to a heat treatment at an oxygen partial pressure and temperature selected to convert a tetragonal BSCCO 2212 oxide into an orthorhombic BSCCO 2212 oxide and, thereafter, roll worked in a high reduction draft in a range of about 40% to 95% in thickness so that the filaments have a constraining dimension is substantially equivalent to a longest dimension of the oxide superconductor grains. The rolled article is sintered to obtain a BSCCO 2223 oxide superconductor.

Abstract: A process is described for formation of oxide films independent of thickness from precursor films comprising metals, metal oxides, and metal fluorides with properties and structures similar to those previously only obtained in thin films, for example less than about 0.4 microns.

Abstract: The method of preparing an oxide superconducting wire comprises steps of preparing a wire by coating raw material powder for a Bi—Pb—Sr—Ca—Cu—O based oxide superconductor including a 2223 phase with a metal and heat treating the wire in a pressurized atmosphere containing oxygen in a prescribed partial pressure, and the total pressure of the pressurized atmosphere is at least 0.5 MPa. The pressure heat treatment apparatus comprises a pressure furnace storing and heat treating a target in a pressurized atmosphere, a pressure regulator for measuring the total pressure in the pressure furnace, an oxygen concentration meter for measuring the oxygen concentration in the pressure furnace and a controller for controlling the oxygen partial pressure in the pressure furnace in response to the total pressure measured by the pressure regulator and the oxygen concentration measured by the oxygen concentration meter.

Abstract: The invention provides a method for stably preparing a bismuth-based high temperature superconductor of a Bi-2223 single-phase or a Bi/Pb-2223 single phase, wherein a second phase is not allowed to reside, at a low cost and efficiently. With the method described above, mixed powders of raw materials (mixed powders of oxides and carbonates), obtained by mixing the raw materials such that a mixing ratio of constituents, Bi:Sr:Ca:Cu or (Bi, Pb):Sr:Ca:Cu, becomes identical to the stoichiometric ratio of a crystal of the superconductor Bi2Sr2Ca2Cu3Oz, or (Bi, Pb) 2Sr2Ca2Cu3Oz, respectively, are used as raw material for sintering, and the sintering is applied thereto, using KCl as a flux. In this case, the raw material for the sintering as calcinated is preferably used, and the sintering is preferably applied at a sintering temperature kept at a constant level.

Abstract: A semiconductor device including a damascene superconducting interconnect, formed of a Ba—Cu—Ca—O superconducting material. A method of forming a superconducting damascene interconnect structure, and the structure made thereby, the method including forming a cavity in an interlevel dielectric; forming a barrier layer in the cavity; forming a seed layer in the cavity over the barrier layer; forming a Cu—Ba alloy layer; filling the cavity by depositing a Cu—Ca—O film; and annealing in oxygen flow to form a Ba—Cu—Ca—O superconductor on the barrier layer. In an alternate embodiment, no barrier layer is formed.

Abstract: The invention features high performing composite superconducting oxide articles that can be produced from OPIT precursors substantially without poisoning the superconductor. In general, the superconducting oxide is substantially surrounded by a matrix material. The matrix material contains a first constraining material including a noble metal and a second metal. The second metal is a relatively reducing metal which lowers the overall oxygen activity of the matrix material and the article at a precursor process point prior to oxidation of the second metal. The second metal is substantially converted to a metal oxide dispersed in the matrix during or prior to a first phase conversion heat treatment but after formation of the composite, creating an ODS matrix.

Abstract: A method for preparing a BSCCO-2223 oxide superconducting article includes annealing an oxide superconductor article comprised of BSCCO-2223 oxide superconductor at a temperature selected from the range of about 500° C.≦T≦787° C. and an annealing atmosphere having an oxygen pressure selected from within the region having a lower bound defined by the equation, PO2(lower)≧3.5×1010 exp(−32,000/T+273) and an upper bound defined by the equation, PO2(upper)≦1.1×1012 exp(−32,000/T+273). The article is annealed for a time sufficient to provide at least a 10% increase in critical current density as compared to the critical current density of the pre-anneal oxide superconductor article. An oxide superconductor having the formula Bi2−yPbySr2Ca2Cu3O10+x, where 0≦x≦1.5 and where 0≦y≦0.6 is obtained, the oxide superconductor characterized by a critical transition temperature of greater than 111.0 K, as determined by four point probe method.

Abstract: A novel process of the production and processing of high quality, high Tc (Bi,Pb)SCCO superconductors starts with fabrication of a precursor article including selected intermediate phases with desired chemical and structural properties. The precursor fabrication includes introducing the reacted mixture having a dominant amount of the tetragonal BSCCO phase into a metal sheath, and sealing the reacted mixture within said sheath, heating the mixture at a second selected processing temperature in an inert atmosphere with a second selected oxygen partial pressure for a second selected time period, the second processing temperature and the second oxygen partial pressure being cooperatively selected to form a dominant amount of an orthorhombic BSCCO phase in the reacted mixture.

Abstract: The present invention includes a method for oxygenating oxide superconductive materials, and superconductive oxide materials made by said method. In broadest terms, the method of the present invention is based on an oxygenation strategy which uses temperatures higher than those typically used in the final stages of the oxygenation processes of the prior art. In the method of the present invention, higher oxygen chemical potentials are used to access higher temperatures to allow for higher oxygen diffusivity without a significant decrease in oxygen solubility.

Abstract: A superconductor with the Bi 2223 high Tc phase is manufactured by mulitply deforming and annealing a structure composed of a material matrix and at least one core of a fabricated material of the superconductor material. At least during an initial segment of a cooling process following the final annealing, the oxygen partial pressure is lowered with decreasing temperature at least in a temperature range between 800° C. and 750° C. for stabilizing the 2223 phase. A rapid cooling to room temperature advantageously follows.

Abstract: An oxide superconductor article is provided having an oxide superconductor film having a thickness of greater than 0.5 microns disposed on a substrate, said article having a transport critical current density (Jc) of greater than or equal to about 105 A/cm2 at 77 K, zero field. The oxide superconductor film is characterized by high Jc and high volume percent of c-axis epitaxial oxide grains, even with thicknesses of up to 1 micron.

Abstract: The present invention includes a method of oxygenating an oxide superconductive material having an initial oxygen content, the method comprising the steps: (a) obtaining an oxide superconductive material, the material having an initial oxygen content; and (b) placing the oxide superconductive material in contact an oxygen-containing media having an oxygen chemical potential greater than that of pure diatomic oxygen at 1 atmosphere pressure and at 300.degree. C., and raising the temperature of the oxide superconductive material to a temperature above about 400.degree. C., and maintaining the oxide superconductive material at the temperature and under the chemical potential of oxygen for sufficient time so as to alter the oxygen content of the oxide superconductive material from the initial oxygen content.

Abstract: A method for producing a superconducting thick film involves the steps of forming a thick layer comprising a superconducting material on a substrate; firing the thick layer formed on the substrate; subjecting the fired thick layer to cold isostatic pressing; and refiring the thick layer subjected to cold isostatic pressing.

Abstract: A process for increasing the resistivity of a HTS oxide composite sheath including heating a superconductive HTS oxide composite, the composite including a sheath including silver, in the presence of mercury at temperatures sufficient to form a silver--mercury alloy is provided together with a HTS oxide composite which includes a high temperature superconductor oxide core surrounded by a metallic sheath, the metallic sheath including silver and mercury.Also provided is a process for preparing a HTS oxide composite having an enhanced transport critical current density including placing the HTS oxide composite within a sealed, evacuated container, and, heating the HTS oxide composite for time and at temperatures sufficient for enhancement of transport critical current density in comparison to the transport critical current density of the HTS oxide composite prior to the heating.

Abstract: The invention provides certain novel metal oxide materials which exhibit superconductivity at elevated temperatures and/or which are useful in electrode, electrolyte, cell and sensor applications, or as electrochemical catalysts. The metal oxide materials are generally within the formulaR.sub.n+1-u-s A.sub.u M.sub.m+e Cu.sub.n 0.sub.w (1)where n.gtoreq.0 and n is an integer or a non-integer, 1.ltoreq.m.ltoreq.2, 0.ltoreq.s.ltoreq.0.4, 0.ltoreq.e.ltoreq.4, and 2n+(1/2)<w<(5/2)n+4, with the provisos that u is 2 for n.ltoreq.1, u is n+1 for 0.ltoreq.

Abstract: A novel ceramic substrate useful for the preparation of superconducting films, said substrate having the formula REBa.sub.2 MO.sub.6 where RE represents rare earth metals--Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and M represents metals Nb, Sb, Sn, Hf, Zr; and a process for the preparation of superconducting YBa.sub.2 Cu.sub.3 O.sub.7-.delta. thick films on new ceramic substrate.

Abstract: A mixture suitable for the production of melt-processed high-temperature superconductors capable of producing a high levitation force. The mixture contains YBa.sub.2 Cu.sub.3 O.sub.7-x powder with a very low content of copper oxide, i.e. copper not bound in with the YBa.sub.2 Cu.sub.3 O.sub.7-x, and a very low carbon content. Also included are stabilizing (so-called "flux-pinning") additives. Also disclosed is a method or producing the mixture, as well as YBa.sub.2 Cu.sub.3 O.sub.7-x powder with suitable low free copper oxide and carbon contents, used to prepare the mixture.

Abstract: The invention provides a structure comprising a high temperature superconducting layer deposited on a ceramic polycrystalline ferrite plate suitable for making commercial microwave devices. In one embodiment, the high temperature superconductor is yttrium barium copper oxide (YBCO), the ferrite is yttrium iron garnet (YIG), and the microwave device is a phase shifter. The method of making this embodiment comprises, polishing the YIG plate, depositing biaxially oriented yttria-stabilized zirconia (YSZ) to form a crystalline template using an ion-beam-assisted-deposition technique, depositing a CeO.sub.2 lattice matching buffer layer using pulsed laser deposition, depositing YBCO using pulsed laser deposition, and annealing the YBCO in oxygen. Etching the YBCO to form a meanderline patterned waveguide results in a high figure-of-merit microwave phase shifter when the device is cooled with liquid nitrogen and an external magnetic field is applied.

Abstract: The present invention relates to a sodium-intervened superconductor and its manufacturing method and more particularly, to the sodium-intervened superconductor expressed by the following Formula 1 and its manufacturing method, wherein the superconductor, prepared from a stoichiometric mixture of Y.sub.2 O.sub.3, NaCuO.sub.2, BaCuO.sub.2, Ln.sub.2 O.sub.3 (Ln: lanthanide ion) and CuO under the atmosphere of oxygen, has some advantages in that a) through the use of NaCuO.sub.2, a ternary oxide, as a reactant, the formation of impurities and sodium evaporation may be prevent, and b) through partial substitution of a divalent barium by a trivalent lanthanide group ion, the superconductor is stable in air with a higher critical current density and critical temperature.Formula 1(Na.sub.1-x Y.sub.x)(Ba.sub.1-y Ln.sub.y).sub.2 Cu.sub.3 O.sub.6+.delta.wherein, Ln is a trivalent lanthanide ion other than Ce and Pr; 0.1<x<0.9; and 0.1<y<0.3.

Abstract: A method is disclosed for fabricating YBa.sub.2 Cu.sub.3 O.sub.7 superconductor layers with the capability of carrying large superconducting currents on a metallic tape (substrate) supplied with a biaxially textured oxide buffer layer. The method represents a simplification of previously established techniques and provides processing requirements compatible with scale-up to long wire (tape) lengths and high processing speeds. This simplification has been realized by employing the BaF.sub.2 method to grow a YBa.sub.2 Cu.sub.3 O.sub.7 film on a metallic substrate having a biaxially textured oxide buffer layer.

Abstract: A precursor is made from a plurality of materials having different vapor pressures. The precursor and a source material are placed in a closed heat treatment furnace. The source material is materials which are the same as some of the materials contained in the precursor and having particular vapor pressures. The precursor and source material is thermally treated in the furnace while the source material is being supplied, so the particular materials in the precursor have their evaporation suppressed, thereby forming compounds. The compounds may be oxide superconductors, oxide dielectric, and so on.

Abstract: A high temperature superconductor (HTS) tri-layer structure and a method for providing the same are described. Preferable two dimensional growth for all layers is provided resulting in smooth surfaces and highly crystalline layers. Full oxygenation of HTS under-layer(s) is provided despite having thick intervening dielectric mid-layer. HTS over- and under-layers are preferably structurally and electrically similar and have high crystallinity, the HTS layers have high T.sub.c (e.g. >90K) comparable to T.sub.c of single layer superconductor layers and a high J.sub.c (e.g. >10.sup.6 A/cm.sup.2), the tri-layer properties do not significantly degrade as the thickness of the layers is increased, and the dielectric mid-layer has high resistivity and is substantially pin-hole free.

Abstract: A process for forming a laminate of 123-type copper oxide superconductor thin films having dissimilar crystal axis orientations, a laminate of 123-type thin copper oxide superconductor layers exhibiting excellent superconducting property, and wiring for Josephson junction. A c-axis oriented single crystalline thin film of an oxide superconductor having a Y:Ba:Cu atomic ratio of substantially 1:2:3 and a lattice constant of 11.60 angstroms.ltoreq.c.ltoreq.11.70 angstroms at a temperature of 20.degree. C. under an oxygen partial pressure of 160 Torr is formed on a single crystalline substrate, and an a-axis oriented single crystalline thin film of said oxide superconductor is formed on the above laminated film relying upon a sputter deposition method.

Abstract: Superconducting transition metal oxide films are provided which exhibit very high onsets of superconductivity and superconductivity at temperatures in excess of 40.degree. K. These films are produced by vapor deposition processes using pure metal sources for the metals in the superconducting compositions, where the metals include multi-valent nonmagnetic transition metals, rare earth elements and/or rare earth-like elements and alkaline earth elements. The substrate is exposed to oxygen during vapor deposition, and, after formation of the film, there is at least one annealing step in an oxygen ambient and slow cooling over several hours to room temperature. The substrates chosen are not critical as long as they are not adversely reactive with the superconducting oxide film. Transition metals include Cu, Ni, Ti and V, while the rare earth-like elements include Y, Sc and La. The alkaline earth elements include Ca, Ba and Sr.

Abstract: The present invention is directed to a process for preparing a HgBaCaCuO superconductor by annealing a precursor mixture comprising a lower member of the homologous HgBaCaCuO superconductor series, a source of calcium and a source of copper. The precursor mixture may further comprise a source of oxygen, a source of rhenium, and, if desired, a source of an additional element selected from the group consisting of halogens and metals other than mercury, barium, calcium, copper and rhenium. The process is particularly effective for preparing (Hg.sub.1-x,Re.sub.x)Ba.sub.2 Ca.sub.2 Cu.sub.3 O.sub.8-y by annealing a precursor mixture containing (Hg.sub.1-x,Re.sub.x)Ba.sub.2 Ca.sub.1 Cu.sub.2 O.sub.6-y at a temperature below about 850.degree. C., wherein x ranges up to about 0.25 and y is a rational number ranging from about negative 1 to about positive 1.

Abstract: A system for applying a volatile element-HTS layer, such as Tl-HTS, to a substrate in a multiple zone furnace, said method includes heating at higher temperature, in one zone of the furnace, a substrate and adjacent first source of Tl-HTS material, to sublimate Tl-oxide from the source to the substrate; and heating at lower temperature, in a separate zone of the furnace, a second source of Tl-oxide to replenish the first source of Tl-oxide from the second source.

Abstract: In order to provide a Tl--Ba--Ca--Cu--O superconductive material which can obtain a stable superconducting state and a method of preparing the same, the oxide superconductive material is expressed in the following composition formula:Tl.sub.x Ba.sub.2 Ca.sub.y Cu.sub.3 O.sub.zwhere x, y and z are in relations satisfying 1.5.ltoreq.x.ltoreq.2.0, 2.0.ltoreq.y.ltoreq.2.5, x+y=4.0 and 9.0.ltoreq.z.ltoreq.11.0, and comprises tetragonal system superconducting phases having lattice constants of a=0.385 to 0.386 nm and c longer than 3.575 nm, to exhibit zero resistance under a temperature of at least 125 K, while the method comprises a step of mixing powder raw materials in blending ratios for satisfying the above composition formula, a step of sintering the as-formed mixed powder in an oxygen jet or in the atmosphere to obtain a sintered body, and a step of annealing the sintered body in a closed atmosphere at 700.degree. to 800.degree. C. for at least 10 hours.

Abstract: Improved superconducting thin films are provided having very high T.sub.c (zero) and J.sub.c values, on the order of greater than or equal to 120K and 10.sup.5 A/cm.sup.2 or greater, respectively. The films of the invention are adapted for deposit and support on a compatible substrate, and include a superconductive material, most preferably Tl.sub.2 Ba.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10, with up to about 10% elemental gold admixed with the superconductive material. The preferred method for fabricating the thin film superconductors comprises first forming a non-superconducting precursor film on a compatible substrate which is placed in contact with an unsintered bulk body containing thallium; the substrate with precursor film are sintered with the bulk body to form the desired superconductor material.

Abstract: The present invention provides a (Bi,Pb)SCCO-2223 oxide superconductor composite which exhibits improved critical current density and critical current density retention in the presence of magnetic fields. Retention of critical current density in 0.1 T fields (77 K, .perp. ab plane) of greater than 35% is disclosed. Significant improvements in oxide superconductor wire current carrying capacity in a magnetic field are obtained by subjecting the oxide superconductor composite to a post-processing heat treatment which reduces the amount of lead in the (Bi,Pb)SCCO-2223 phase and forms a lead-rich non-superconducting phase. The heat treatment is carried out under conditions which localize the lead-rich phase at high energy sites in the composite.

Abstract: A method of producing ceramic superconducting materials such as YBa.sub.2 Cu.sub.3 O.sub.x includes blending together starting materials for the superconducting material. The blend of starting materials are formed into a layer and sintered at a temperature above the peritectic temperature for the superconducting material. Prior to sintering, the starting materials for the superconducting material may be unreacted. The starting materials may also be partially reacted prior to sintering by calcining for a period of time at a temperature which does not result in full reaction of the starting materials to the chemical composition of the desired superconducting material.

Abstract: The hole density of an oxide superconductor having holes as carriers is higher than the hole density to bring the highest value of the superconductivity critical temperature Tc thereof, and it can be made higher than the optimal density to bring the highest Tc value by treating the oxide superconductor with heat in an oxidizing gas atmosphere, or by replacing positive ions constituting the oxide superconductor except for copper with ions of a low valence number. Accordingly, it is possible to substantially reduce the rate of decrease of the critical current density owing to an applied magnetic field when the magnetic field is applied parallel to the crystal c axis, and to allow a current conductor produced by using the oxide superconductor to have high critical current density.

Abstract: An oxide is formed which will form an oxide superconductor containing a Cu-O atomic layer. The oxide is hydrogenated. The oxide is oxidized after it is hydrogenated. The hydrogenation and the oxidization are executed simultaneously with or after the oxide is formed. The hydrogenation and the oxidization improve the superconducting characteristics of the oxide superconductor.

Abstract: A holder (1) provided with a spirally extending groove (2) is prepared and an oxide superconducting wire (3) is arranged in the groove (2) to be heat treated, so that each portion thereof is not bonded to another portion during the heat treatment.

Abstract: A process for controlling crystalline orientation of an oxide superconductive film includes a first-heat-treatment step, and a second-heat-treatment step. In the first-heat-treatment step, an oxide superconductive film is heated and held in non-oxidizing atmosphere. Accordingly, partial oxygen deficiency is caused in the oxide superconductive film. In the second-heat-treatment step, the oxide superconductive film is heated and held in oxygen-rich atmosphere. Consequently, oxygen is re-introduced into the oxide superconductive film. Thus, crystalline orientation of the oxide superconductive film is altered. The process enables to readily form not only an "a"-axis-oriented oxide superconductive film but also a "b"-axis-oriented oxide superconductive film.

Abstract: Process for increasing the pinning force of superconducting Bi-Sr-Ca-Cu-O ceramic moldings, which comprises heating the pure-phase 2212 phase of a Bi-Sr-Ca-Cu-O ceramic molding under pure oxygen or an oxygen-containing gas for from 1 to 40 minutes to a temperature of from 825.degree. to 900.degree. C. and generating secondary-phase precipitates in the process.

Abstract: The present invention provides an oxide superconductor which is expressed in the composition formula(Pb.sub.1-x-y M.sub.x (A1).sub.y)(A2).sub.2 (A3).sub.n-1 (Cu).sub.n (O).sub.2n+3+z(wherein 0.ltoreq.0.6, 0.ltoreq.y.ltoreq.0.6, x+y.ltoreq.0.6, n denotes integers of 1 or more, -0.6.ltoreq.z.ltoreq.0.5, M denotes Cu or Cd, and A1, A2 and A3 denote at least one element of Ba, Sr, and Ca, respectively) and which has a crystal structure stacking rock salt structure based portions and infinite layer structure portions, wherein the rock salt structure based portion has a structure that an atoms layer having 0.5-1.5 oxygen atoms, in case the total atoms number of Pb, M and A1 is one, and an atoms layer having one or less oxygen atoms per one A2 atom, are stacked and the infinite layer structure portion has a structure that an atoms layer having 2 oxygen atoms per one Cu atom and an atoms layer of A3 atoms only, are stacked.

Abstract: A description is given of superconducting substances having a content of Bi, Sr, Ca and Cu, and of processes for their preparation from the metal oxides within a range which is specified by the overall composition Bi.sub.a (Sr,Ca).sub.b -Cu.sub.6 O.sub.x, where a=3-24 and b=3.23-24, with an Sr/Ca atomic ratio of 1:9-9:1 and a Bi:(Ca+Sr) atomic ratio of 0.3-1.5. The transition temperature is at least 60 K. The principal phase crystallizes in the orthorhombic system. The pure compounds Bi.sub.4 (Sr,Ca).sub.4 Cu.sub.2 O.apprxeq..sub.12 and Bi.sub.4 (Sr,Ca).sub.6 Cu.sub.4 O.apprxeq..sub.20.

Abstract: A strongly-linked polycrystalline oxide superconductor article includes an oxide superconductor selected from the group consisting 124-type and 247-type oxide superconductors having fine, highly aligned oxide superconductor grains less than 50 .mu.m along a longest dimension. The oxide superconductor article has at least a 25% retention of critical current density in a 0.1 Tesla field.

Abstract: The present invention is directed to a process for producing high temperature superconducting ceramic materials. More particularly, the present invention is directed to a process that enhances the densification of Bi.sub.1.8 Pb.sub.0.4 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10 "BSCCO" ceramics.

Abstract: A method for preparing a BSCCO-2223 oxide superconducting article includes annealing an oxide superconductor article comprised of BSCCO-2223 oxide superconductor at a temperature selected from the range of about 500.degree. C..ltoreq.T.ltoreq.787.degree. C. and an annealing atmosphere having an oxygen pressure selected from within the region having a lower bound defined by the equation, P.sub.O2 (lower).gtoreq.3.5.times.10.sup.10 exp(-32,000/T+273) and an upper bound defined by the equation, P.sub.O2 (upper).ltoreq.1.1.times.10.sup.12 exp(-32,000/T+273). The article is annealed for a time sufficient to provide at least a 10% increase in critical current density as compared to the critical current density of the pre-anneal oxide superconductor article. An oxide superconductor having the formula Bi.sub.2-y Pb.sub.y Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10+x, where 0.ltoreq.x.ltoreq.1.5 and where 0.ltoreq.y.ltoreq.0.

Abstract: A process for producing coherent twin, incoherent twin, low angle tilt, high angle tilt or CSL grain boundaries in materials is described. A planar material or a planar substrate coated with the polycrystalline material is heated in selected areas so as to provide a temperature gradient in the substrate. The temperature gradient is sufficiently large and maintained for a sufficient time so that preferential nucleation occurs and recrystallization in the plane of the polycrystalline material takes place such that coherent twin, incoherent twin, low angle tilt, high angle tilt or CSL boundaries between chains of grains growing along lines of equal temperature are produced.

Abstract: Described is a process for manufacturing thin films by periodically depositing (DEP) a number of block layers consisting of different base materials on a substrate (multilayer deposition), wherein the thickness of the layers (LT) is restricted to one to 20 monolayers and deposition as well as crystallization of the thin film is completed at approximately constant temperature without performing a separate annealing step. The method can be used to produce thin films of high-T.sub.c -superconductors. It allows a better control of the crystal growth of ternary or higher compounds with comparatively large unit cells.

Abstract: A method of preparing a superconducting oxide by combining the metallic elements of the oxide to form an alloy, followed by oxidation of the alloy to form the oxide. Superconducting oxide-metal composites are prepared in which a noble metal phase intimately mixed with the oxide phase results in improved mechanical properties. The superconducting oxides and oxide-metal composites are provided in a variety of useful forms.

Abstract: A method of producing a Bi-Pb-Sr-Ca-Cu oxide superconductor by thermally treating raw material comprises steps of performing first plastic deformation on the raw material, performing first heat treatment on the material being subjected to the first plastic deformation, performing second plastic deformation on the material being subjected to the first heat treatment, and performing second heat treatment on the material being subjected to the second plastic deformation.

Abstract: A method for preparing an oxide superconductor article includes exposing the article after deformation of the article to a final heat treatment having the steps of (a) heating the article at a temperature sufficient to partially melt the article, such that a liquid phase co-exists with the desired oxide superconductor phase; and (b) cooling to and holding the article at a temperature sufficient to transform the liquid phase into the desired oxide superconductor, where no deformation occurs after the final heat treatment. The liquid phase of step (a) wets surfaces of a defect contained within the mixed phase, whereby upon transformation of the liquid in step (b) to the desired oxide superconductor, the defect is healed.

Abstract: In order to obtain a ceramics system superconducting wire, a bulk type ceramics system superconductor or its precursor previously treated to have orientativity in its crystal structure is reduced in diameter in a state charged in a metallic pipe, thereby being elongated, and then heat treated. In the as-formed superconducting wire, crystal orientativity of a bulk formed of the superconductor or its precursor is maintained, whereby it is possible to obtain a superconducting wire having high critical current density. In order to further improve the critical current density, it is effective that the diameter reduction working step and the heat treatment step are alternately repeated a plurality of times.