Abstract:
The invention relates to multi-layer articles and methods of making such articles. The methods include first conditioning the surface of an underlying layer, such as a buffer layer or a superconductor layer, then disposing a layer of another material such as a buffer, superconductor or cap layer on the conditioned surface. The conditioned surface can be a high quality surface. Superconductor articles formed by these methods can exhibit relatively high critical current densities. The conditioning involves thermal and/or chemical treatments using gaseous or liquid agents.
Abstract:
The invention relates to multi-layer articles and methods of making such articles. The methods include first conditioning the surface of an underlying layer, such as a buffer layer or a superconductor layer, then disposing a layer of another material such as a buffer, superconductor or cap layer on the conditioned surface. The conditioned surface can be a high quality surface. Superconductor articles formed by these methods can exhibit relatively high critical current densities. The conditioning involves thermal and/or chemical treatments using gaseous or liquid agents.
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 mixing raw powders with a desired ratio of Bi:Pb:Sr:Ca:Cu elements and reacting the mixture under different selected reaction conditions that form a precursor powder with a dominant (Bi, Pb)SCCO 2212 phase and without Ca-Pb-O phase, wherein the 2212 phase may be the orthorhombic 2212 phase. The precursor article is then subjected to optimized reaction and mechanical deformation processes that lead to a reaction induced texturing and deformation induced texturing, respectively. A heating process is used to convert the precursor powder to the 2223 phase and subsequent deformation and annealing processes may be used to form a substantially single phase, highly textured (Bi, Pb)SCCO 2223 superconductor with high Jc.
Abstract:
Processes for the fabrication of MgB2 powder and wires are provided. Powders are produced by mechanically alloying magnesium- and boron-containing precursors under controlled conditions to avoid secondary phase and impurity formation. Powders are also prepared by vapor phase reaction of volatile magnesium- and boron-containing precursors. Wires, tapes, films and coatings are provided.
Abstract:
Processes for the fabrication of MgB2 powder and wires are provided. Powders are produced by mechanically alloying magnesium- and boron-containing precursors under controlled conditions to avoid secondary phase and impurity formation. Powders are also prepared by vapor phase reaction of volatile magnesium- and boron-containing precursors. Wires, tapes, films and coatings are provided.
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:
Coated conductors (40) and methods of fabricating the same are provided, for minimizing a.c. losses during operation. Multilayered articles include multiple conductive layers (46, 47) in electronic communication through interlayer connections (54, 60). Conductive paths (50) are fabricated on the conductive layers and through interlayer connections between these layers so that current travels the length of the conductors with minimal a.c. losses. Preferably at least one of the superconductive layers (46, 47) is formed epitaxially on a substrate (42) covered with a biaxially textured buffer layer (44), the interlayer connections (54, 60) traversing an insulating or highly resistive layer (49).
Abstract:
Coated conductors (40) and methods of fabricating the same are provided, for minimizing a.c. losses during operation. Multilayered articles include multiple conductive layers (46, 47) in electronic communication through interlayer connections (54, 60). Conductive paths (50) are fabricated on the conductive layers and through interlayer connections between these layers so that current travels the length of the conductors with minimal a.c. losses. Preferably at least one of the superconductive layers (46, 47) is formed epitaxially on a substrate (42) covered with a biaxially textured buffer layer (44), the interlayer connections (54, 60) traversing an insulating or highly resistive layer (49).
Abstract:
The invention relates to methods of making a superconductor. A superconductor precursor layer (15) is deposited on a substrate (12) having optional intermediate or buffer layers (16, 18, 22) by a solution coating method and treated using relatively few temperature ramps, varying pressures of water vapor, and/or isothermal treatment steps. The methods and compositions can be used to form superconductor material intermediates preferably metal oxyfluoride intermediates of YBCO that have relatively few cracks and/or blisters.
Abstract:
The invention relates to methods of making a superconductor. A superconductor precursor layer (15) is deposited on a substrate (12) having optional intermediate or buffer layers (16, 18, 22) by a solution coating method and treated using relatively few temperature ramps, varying pressures of water vapor, and/or isothermal treatment steps. The methods and compositions can be used to form superconductor material intermediates preferably metal oxyfluoride intermediates of YBCO that have relatively few cracks and/or blisters.