Abstract: To provide a manufacturing method of a superconducting radio-frequency acceleration cavity used in a charged particle accelerator enabling the manufacturing with few waste amounts of the niobium material at low cost in a short time, the manufacturing method has each of the steps of (a) obtaining an ingot made from a disk-shaped niobium material, (b) slicing and cutting the niobium ingot into a plurality of niobium plates each with a predetermined thickness, by vibrating multiple wires back and forth while spraying fine floating abrasive grains with the niobium ingot supported, (c) removing the floating abrasive grains adhered to the sliced niobium plates, and (d) performing deep draw forming on the niobium plates and thereby obtaining a niobium cell of a desired shape.

Abstract: To provide a manufacturing method of a superconducting radio-frequency acceleration cavity used in a charged particle accelerator enabling the manufacturing with few waste amounts of the niobium material at low cost in a short time, the manufacturing method has each of the steps of (a) obtaining an ingot made from a disk-shaped niobium material, (b) slicing and cutting the niobium ingot into a plurality of niobium plates each with a predetermined thickness, by vibrating multiple wires back and forth while spraying fine floating abrasive grains with the niobium ingot supported, (c) removing the floating abrasive grains adhered to the sliced niobium plates, and (d) performing deep draw forming on the niobium plates and thereby obtaining a niobium cell of a desired shape.

Abstract: A process for the oxygenation of ceramic high T.sub.c superconductors is disclosed. The superconductor is formed from a sintered powdered ceramic. Microchannels are formed in the ceramic material by embedding in the powder a plurality of wires or fibers formed of a material which is thermally removable during the sintering process to leave thin, continuous, tubular channels. After sintering, the ceramic is exposed to oxygen in a high temperature, high pressure environment. The microchannels aid in the transport of oxygen into the interior of the material by providing passages along which the oxygen travels prior to diffusing into the material. The lengths of the diffusion paths in the material are thereby greatly shortened. In another embodiment, the channels are formed after sintering and prior to oxygenation by drilling, punching, or etching.

Abstract: Enhanced flux pinning in superconductors is achieved by embedding carbon nanotubes into a superconducting matrix. The carbon nanotubes simulate the structure, size and shape of heavy ion induced columnar defects in a superconductor such as Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8+x. The nanotubes survive at treatment temperatures of up to approximately 800.degree. C. both in oxygen containing and in inert atmospheres. The superconducting matrix with nanotubes is heat treated at a lower temperature than the temperature used to treat the best case pure superconductor material.

Abstract: A method for improving the phase purity of a multiphase ceramic high temperature superconductor by selective microwave heating of undesired phases in a multiphase material to cause a phase transformation of the undesired phase to the desired phase. The selective microwave heating may be employed during initial firing and sintering of the ceramic superconductor compound or as a subsequent annealing step. Plane polarized microwave energy may be employed to enhance the two dimensional anisotropy of the compound by similar selective heating.

Abstract: Process for preparing a high temperature superconductor such as yttrium bum copper oxides, by dissolving suitable proportions of hydrolyzable salts, oxides, or organometallic compounds of yttrium, barium and copper in an acid pH-controlled water-containing organic solvent such as methanol, and subjecting the resulting solution to ultrasonic energy or to an oxidation-reduction reaction, preferably while passing oxygen under a positive pressure through the solution, and precipitating a hydrolyzed precursor material. Such precursor material is then heated or annealed at temperatures between about 300.degree. C. and about 600.degree. C., also preferably in the presence of flowing oxygen, to produce the desired high temperature superconductor material.