Basf Se Corporation

Nexans

Zenergy Power Gmbh

Nexans Superconductors Gmbh

Ghent University

Michael Baecker

Martina Falter

Joachim Bock

Isabel Van Driessche

Oliver Brunkahl

Ron Feenstra

Matthias Maier

Heribert Walter

Bernhard Holzapfel

Maximilian Hemgesberg

Herbert Carl Freyhardt

Till Gruendling

Theodor Schneller

Katrien De Keukeleere

Andreas Leenders

Kerstin Knoth

Jonathan De Roo

Serge Hoste

Denis Schwall

Hens Zeger

Brigitte Schlobach

Martin Ullrich

Oliver Thiems

Mario Sadewasser

Thomas Freudenberg

Jan Bennewitz

Pieter Vermeir

Hannes Rijckaert

Sandip Halder

Matina Falter

Jan Kunert

Brygida Wojtyniak

Thorsten Martin Staudt

Viktor Weimann

Ruben Huehne

Barbara Schuepp-Niewa

Thorsten Staudt

The present invention is in the field of processes for the production of high temperature super-conductor wires. In particular, the present invention relates to a process for the production of high temperature superconductor wires comprising heating a film comprising yttrium or a rare earth metal, an alkaline earth metal, and a transition metal to a temperature of at least 700&#xb0; C. and cooling the film to a temperature below 300&#xb0; C., wherein the heating and cooling is per-formed at least twice.

Process for the production of high temperature superconductor wires

The present invention is in the field of nanoparticles, their preparation and their use as pinning centers in superconductors. In particular the present invention relates to nanoparticles comprising an oxide of Sr, Ba, Y, La, Ti, Zr, Hf, Nb, or Ta, wherein the nanoparticles have a weight average diameter of 1 to 30 nm and wherein an organic compound of general formula (I), (II) or (III) or an organic compound containing at least two carboxylic acid groups on the surface of the nanoparticles (I) (II) (III) wherein a is 0 to 5, b and c are independent of each other 1 to 14, n is 1 to 5, f is 0 to 5, p and q are independent of each other 1 to 14, and e and f are independent of each other 0 to 12. 

Nanoparticles for the use as pinning centers in superconductors

The present invention relates to a precursor () for production of a high-temperature superconductor (HTS) in ribbon form, comprising a metallic substrate () in ribbon form having a first ribbon side () and a second ribbon side (), wherein, on the first ribbon side (), (a) the substrate () has a defined texture as template for crystallographically aligned growth of a buffer layer or an HTS layer and (b) an exposed surface of the substrate () is present or one or more layers () are present that are selected from the group consisting of: buffer precursor layer, pyrolyzed buffer precursor layer, buffer layer, HTS precursor layer, pyrolyzed HTS buffer precursor layer and pyrolyzed and further consolidated HTS buffer precursor layer, and, on the second ribbon side (), at least one ceramic barrier layer () that protects the substrate () against oxidation or a precursor which is converted to such a layer during the HTS crystallization annealing or the pyrolysis is present, wherein, when one or more layers () are present on the first ribbon side (), the ceramic barrier layer () or the precursor thereof has a different chemical composition and/or a different texture than the layer () arranged on the first ribbon side () and directly adjoining the substrate (). In this precursor, the barrier layer () is a layer that delays or prevents ingress of oxygen to the second ribbon side () and is composed of conductive ceramic material or a precursor which is converted to such a precursor during the HTS crystallization annealing or the pyrolysis, and the ceramic material is an electrically conductive metal oxide or an electrically conductive mixture of metal oxides, wherein the conductive metal oxide or one or more metal oxides in the conductive mixture is/are preferably metal oxide(s) doped with an extraneous metal.

Pre-product and method for producing a strip-like high-temperature superconductor

The invention relates to a method for producing a composite comprising a high-temperature superconductor (HTS) layer based on rare earth metal-barium-copper oxide on a substrate with defined biaxial texture, having the following steps: applying a first HTS coating solution to the substrate, drying the first HTS coating solution to produce a first film, pyrolyzing the first film to produce a first pyrolyzed sublayer, removing an interfacial layer on the upper side of the first pyrolyzed sublayer to produce a first pyrolyzed sublayer with reduced layer thickness, applying a second HTS coating solution to the first pyrolyzed sublayer with reduced layer thickness, drying the second HTS coating solution to produce a second film, pyrolyzing the second film to produce a second pyrolyzed sublayer, optionally forming one or more further pyrolyzed sublayers on the second pyrolyzed sublayer, and crystallizing the overall layer formed from the pyrolyzed sublayers to complete the HTS layer, wherein the removal of the interfacial layer in step D) is effected in such a way that a texture determined by the defined biaxial texture of the substrate is transferred to the first and also to the second pyrolyzed sublayer, and also to a product producible by such a method.

Method for producing a composite comprising a high-temperature superconductor (HTS) layer

Known processes for the production of nanoparticles of compounds of the transition metals Zr, Ti, Ta, rare earths (RE), Mn, and Fe via microemulsions lead to products that contain impurities from the reactants, particularly water, which make the further use of said nanoparticles difficult, for instance in high-temperature super conductors (HTSC). It is proposed that the nanoparticles be produced via anhydrous microemulsions having an outer phase composed of a nonpolar solvent and inner phase composed of a polar anhydrous solvent. The nanoparticles thus obtained exhibit good monodispersity and can be used in the production of REBaCuOsuper conductors by incorporation into the precursor coating solution.

Process for producing nanoparticles and their use in the production of high-temperature superconductors

The invention relates to a method for the wet chemical production of an HTSL on a carrier, wherein an HTSL precursor solution comprising no trifluoroacetate may be utilized if the same is heated to a temperature Tduring the heat treatment of the HTSL precursor, wherein the remaining substances of the HTSL precursor solution form at least a partial melt, which is below the temperature at which REBaCuOis formed, and which is deposited from the liquid phase while forming a peritectic.

Wet-chemical method for producing high-temperature superconductor

A high-temperature superconducting thin-film strip conductor (HTSL-CC) includes a metal substrate, a buffer layer chemically generated thereon and grown crystallographically unrotated in relation to the metal substrate, and a chemically generated superconducting coating thereon. The HTSL-CC possesses high texturing of the buffer layer since the metal substrate has a surface roughness RMS&#x3c;50 nm, and since and the buffer layer is grown directly onto its surface, without an intermediate layer, crystallographically unrotated in relation to the crystalline structure of the metal substrate.

Substrate for a superconducting thin-film strip conductor

A method is proposed for producing a biaxially textured metal substrate having a metal surface, wherein the substrate is modified in order to produce a high-temperature superconductor coating arrangement and wherein the metal surface is modified in order to deposit a buffer layer or another intermediate layer epitaxially thereon and/or to deposit an oriented high-temperature superconductor (HTS) layer thereon. The method includes producing a biaxially textured metal substrate, subjecting the metal substrate surface to a polishing treatment, in particular an electropolishing treatment, and subjecting the metal substrate to a post-annealing after the surface polishing treatment and before a subsequent coating is performed involving epitaxial deposition of a layer of the HTS coating arrangement. This method results in smooth metal substrates with high textural overcoats and thereby improved HTS layers.

Method for producing metal substrates for HTS coating arrangements

A high-temperature superconductor layer arrangement includes at least one substrate and one textured buffer layer made of oxidic material. The buffer layer displays at least one further constituent forming a homogeneous mixed-crystal layer. The further constituent is a transition metal from the first subgroup and/or forming at least a partial melt with the oxidic buffer material at an annealing temperature of &#x2266;1,600 degrees Celsius. The further constituent can particularly be copper and/or silver.

High-temperature superconductive layer arrangement

A method of producing a thin layer, high-temperature superconductor strip is disclosed. In the method, a metal salt solution is formed and coated onto a substrate including a high-temperature superconductor layer. Heat is then applied directly or indirectly to the solution. The metal salt solution may contain a metal-organic salt solution or a metal inorganic metal salt solution. When an inorganic metal salt solution is utilized, a reducing solution may also be applied to the HTSC layer prior to heating. In addition, nano-sized metal particles may be added to the metal salt solution and/or the reducing solution.

Process of forming a high-temperature superconductor

The invention relates to a method for producing a high temperature superconductor (HTSC) from a strip including an upper side precursor layer and which, for continuous sintering of the precursor layer within a furnace in the presence of a fed-in reaction gas, is drawn across a support. A furnace for performing the method is also described.

Sintering furnace for producing an HTSC strip

Method for producing an HTSC strip

The invention relates to a process for applying a resistive layer on an oxide superconducting element for electrically decoupling superconducting filaments contained in the element, an oxide superconducting element having a resistive layer and use thereof, in particular in ac applications, the resistive layer being formed by chemically converting the surface of a conducting metal coating sheating the superconducting core of said filaments into a salt of a metal constituting said conducting coating.

Metal salt resistive layer on an superconducting element

A method of curing cracks in a ceramic shaped body made from ceramic magnet materials or ceramic superconductor materials, in which a filling material which melts at a lower temperature than the material of the shaped body or is flowable at a lower temperature than the material of the shaped body is applied to the surface of the shaped body at least in the area of a crack and/or is introduced into at least one crack, in which the shaped body with the filling material is heated to and maintained at a temperature at which the material of the shaped body does not yet melt or is not yet flowable, but at which the filling material is in at least partially molten and flowable state at least until the fused filling material can penetrate at least partially into the crack, in which the filling material consists of non-metallic or essentially of non-metallic compounds and is at least partially crystallized, and in which the shaped body with the filling material is cooled, wherein the thermal crystallization conditions for the filling material are selected in such a way that the filling material grows epitaxially on the crack face.

Method for curing cracks in ceramic shaped bodies and shaped bodies treated in such a manner

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Cologne, Germany

Michael Baecker