Abstract: The present invention is related to a superconductive ceramic wire and a method for making same. According to the first aspect of the invention, there is provided a method for making a superconductive ceramic wire, the method comprising the steps of: (a) preparing a superconductive porous ceramics; (b) depositing lead in the pores of the ceramics; (c) covering the lead-depositted ceramics with a metal; and (d) extending the metal-clad and lead-deposited ceramics. According to the second aspect of the invention, there is provided a superconductive ceramic wire which is obtained by: (a) preparing a superconductive porous ceramics; (b) depositing lead in the pores of the ceramics; (c) covering the lead-depositted ceramics with a metal; and (d) extending the metal-clad lead-depositted ceramics.

Abstract: A process for fabricating worked superconducting ceramic material of a mean grain size not more than 10 um is disclosed, which comprises the steps of: (a) preparing a metal casing containing a starting powder material having a composition for forming an oxide superconductor; (b) calcining the starting powder material contained in the casing at a temperature range of 850.degree. to 950.degree. C.; (c) subjecting said casing to a HIP treatment; (d) subjecting said casing containing hot deformed material to cold deformation processing; and (e) subjecting said casing to stress relief treatment by annealing in the presence of oxygen.

Abstract: The present invention is related to a superconductive ceramic wire and a method for making same.According to the first aspect of the invention, there is provided a method for making a superconductive ceramic wire, the method comprising the steps of: (a) preparing a superconductive porous ceramics; (b) depositing lead in the pores of the ceramics; (c) covering the lead-deposited ceramics with a metal; and (d) extending the metal-clad and lead-deposited ceramics.According to the second aspect of the invention, there is provided a superconductive ceramic wire which is obtained by: (a) preparing a superconductive porous ceramics; (b) depositing lead in the pores of the ceramics; (c) covering the lead-deposited ceramics with a metal; and (d) extending the metal-clad lead-deposited ceramics.

Abstract: A superconducting structural body comprising an oxide based superconducting ceramics powder having a perovskite structure and a metal sheath surrounding the oxide based superconducting ceramics powder, the metal sheath including an Ag portion and a non-Ag metal portion, the Ag portion existing from the inner to outer surfaces of the metal sheath, a superconducting ceramics powder portion existing in the structural body, the non-Ag metal protion used as a structural material of the metal sheath of an outermost layer of the structural body, the superconducting ceramics powder portion and the non-Ag metal portion being disposed so as to be indirectly contact each other through the Ag material, and the superconducting structural body having a compressed oriented layer in which the C-axis of the crystal in the superconducting ceramics powder is oriented in the direction perpendicular to the longitudinal direction of the superconducting structural body, and in which a thickness thereof is not smaller than 5 .mu.

Abstract: A superconducting structural body comprisinga superconducting ceramics anda metal sheath surrounding the superconducting ceramics,the metal sheath includingan Ag portion anda non-Ag metal portion, the Ag portion existing from inner to outer faces of the metal sheath, and the superconducting ceramics portion existing in the structural body and the non-Ag metal portion used as a structural material for the metal sheath as the outermost indirectly contacting each other through the Ag material.

Abstract: A method of manufacturing a superconductive coil by means of explosive compaction. A wire formed of silver having a superconductive oxide powder charged therein is formed into a coil. The coil is placed within a cylindrical vessel, into which a pressure medium is charged. Explosive compaction is carried out to cause the compaction of the coil through the cylindrical vessel and the pressure medium and hence densify the coil. The compacted coil is heat-treated in an air or oxygen atmosphere. The resulting superconductive coil possesses high critical electric current density. Advantageously, the coil is mounted on a mandrel axially extending therethrough, and placed together with the mandrel into the cylindrical vessel, before explosive compaction.

Abstract: A method of controlling the crystal grain size of UO.sub.2 pellets is disclosed, which comprises(1) providing an aqueous uranyl solution which is free of hydrofluoric acid and nitric acid and which contains uranyl fluoride (UO.sub.2 F.sub.2) and/or uranyl nitrate (UO.sub.2 (NO.sub.3).sub.2) as a uranium component,(2) reacting with ammonia said aqueous uranyl solution to precipitate ammonium diuranate (ADU), while adjusting the ratio of said uranium components to a predetermined value within the range varying from the ratio 100% of uranyl fluoride and 0% of uranyl nitrate to the ratio 0% of uranyl fluoride and 100% of uranyl nitrate, adjusting the uranium concentration of the reaction mixture to 50 to 1,000 gU/liter and also adjusting the rate of contact between said uranium component in said aqueous uranyl solution with ammonia to at least 2 moles NH.sub.3 /min/mole U,(3) calcining and reducing said ADU precipitate to form UO.sub.2 powder, and(4) molding and sintering said UO.sub.2 powder, thus producing UO.