United States of America As Represented by the Secretary of the Air Force

Mikhail Klugerman

Michael J Suscavage

L Pierre De Rochemont

Daniel F Ryder, Jr

Daniel E Ryder

Pierre L deRochemont

This invention permits superconducting ceramics, as well as other ceramic materials, to be spray deposited onto indefinitely large sheets of metallic substrate from a carboxylic acid salt solution. Elemental metal precursors of the superconductor are introduced into the solution as carboxylic acid salts. The deposit formed on the malleable metallic substrate is then thermomechanically calcined to form c-axis textured metal-superconductor composite sheet structures. These composite sheet structures can be formed by pressing together two ceramic-substrate structures, ceramic face-to-face, to form a metal-ceramic-metal sheet structure, or by overlaying a metal sheet over the deposited structure. Once the structure has been thermomechanically calcined, the c-axis of the superconductor is oriented parallel to the vector defining the plane of the metal sheet, i.e., perpendicular to the surface of the plane. These sheets of c-axis textured superconductor can then be mechanically worked as continuous superconducting filaments into larger composite structures with predetermined c-axis orientation. The fact that the c-axis of the superconductor is given predetermined orientation allows surface topologies to be mechanically constructed from these sheets that maximize the performance of the superconductor for a predetermined application or magnetic field environment.

Superconducting metal-ceramic laminate

The invention provides methods to manufacture dense, complex c-axis oriented ceramic oxide layers with thickness greater than 2.5 microns (.mu.m) on a metallic substrate (composites) without the use of an interfacial barrier, buffer, or surface layer using a metalorganic deposition process and thermomechanical reaction treatments is disclosed. A porous amorphous metal oxide ceramic deposit is formed directly on the substrate by spray pyrolyzing a mixed metalorganic precursor solution onto the metallic substrate. The metallic substrate has been previously heated to temperatures greater than the boiling point of the organic solvent and are high enough to initiate in situ decomposition of the metalorganic precursor salts. The process does not apply the precursor solution to the substrate as a liquid coating that is pyrolyzed in subsequent processing steps. The resultant porous amorphous oxide deposit is processed into a dense amorphous ceramic, or a fully crystallized c-axis oriented ceramic through a series of mechanical compression and short reaction treatments that are used to crystallize the amorphous ceramic layer. The inventive method applies to making complex ceramic oxides including superconducting compositions of bismuth cuprate ceramic, piezoelectric or insulating compositions. The composites so produced are useful in devices that include ceramic sputtering targets, heat shields, electrically conducting wires, magnetic solenoids, electromagnetic shielding, and energy storage devices. The invention also provides the ceramic-metal composites so made.

Method for making ceramic-metal composites and the resulting composites

Super conducting metal-ceramic composite

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Acton, MA, United States of America

Mikhail Klugerman