Hitachi, Ltd.

Atsuko Soeta

Takaaki Suzuki

Tomoichi Kamo

Shinpei Matsuda

Kunihiro Maeda

Seizi Takeuchi

Yutaka Yoshida

Ken Takahashi

Tadahiko Miyoshi

Takeo Yamazaki

Yukio Takeda

Toshiya Doi

Kie Nakamura

Masatoshi Nakazawa

Choushiro Kitazawa

Akira Yoshinari

Kazutoshi Higashiyama

Hideyo Kodama

Yoshimi Yanai

Akira Okayama

Teruo Kumagai

Tsuneyuki Kanai

A superconducting oxide wire and a method of manufacturing the same are disclosed. The wire comprises a pipe made of a metal and a superconducting oxide material filling the interior of the pipe and comprising superconducting oxide grains which are bonded to each other and which have a perovskite crystal structure having a C face and a C axis. The superconducting oxide grains contain more than 50 vol % of plate-shaped grains of which the length in the direction of the C face is greater than the length in the direction of the C axis. The C faces of most the plate-shaped grains are arranged to be directed toward longitudinal axis of the pipe.

Superconducting wire and method of manufacturing the same

An oxide superconductor comprising a perovskite type oxide compound of thallium, strontium, calcium and copper or thallium, strontium, balium, calcium and copper is produced by absorbing thallium in a gaseous phase into a mixture of strontium oxide or strontium oxide and barium oxide, calcium oxide, and copper oxide or a mixture of compounds capable of producing these oxides upon firing. From this superconductor are provided a superconductor wire material, tape-shaped wire material, coil, thin film, magnet, magnetic shielding material, printed circuit board, measuring device, computer, power storing device and etc.

Tl.sub.1 (Ba.sub.1-x Sr.sub.8).sub.2 Ca.sub.2 Cu.sub.3 Oy oxide

A method of producing a high-temperature oxide superconducting material, which comprises the steps of (a) preparing a material corresponding to an oxide superconductor of the perovskite type structure consisting essentially of a first member selected from the group consisting yttrium, lanthanoids, thallium and bismuth; at least one alkaline earth metal; copper; and oxygen and (b) heating the material in the presence of an alkali metal selected from the group consisting of potassium, sodium, rubidium and cesium to a temperature around the melting point of the alkali metal or to a higher temperature for a time sufficient to effect grain growth in the superconductor material, thereby to produce the superconductor containing the alkali metal in an amount not larger than 4 mole % based on the first member.

Oxide high-temperature superconducting material, method of preparing

Superconductors using oxide superconducting materials having pinning centers inside crystal grains are enhanced in transmissible critical current density and allowed to have a high critical current density even in the magnetic field. A superconductor is produced comprising superconducting materials having a high irreversible magnetic field where the c axes of their crystals are oriented in one direction. This can be practically realized by heat-treating a superconducting material having the composition (Tl.sub.1-X1-X2 Pb.sub.X1 Bi.sub.X2)(Sr.sub.1-X3 Ba.sub.X3).sub.2 Ca.sub.2 Cu.sub.3 O.sub.9+X4 together with Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8 having a tendency of growing in the form of plate crystal. Various apparatuses capable of working under cooling with liquid nitrogen let alone with liquid helium and having a high superconducting critical current density even in a high magnetic field can be produced.

Laminated super conductor oxide with strontium, calcium, copper and at

This invention provides an oxide superconductor having a composition of the following general formula of (Tl.sub.a Bi.sub.b Pb.sub.c).sub.x (Sr.sub.d Ba.sub.e).sub.2y (Ca.sub.f Ln.sub.g).sub.y(n-1) Cu.sub.wn O.sub.2n+3+.delta., wherein Ln is at least one selected from Y and rare earth elements, n is 2, 3 or 4, -1&lt;.delta.1, 0.8.ltoreq.x.ltoreq.1.2, 0.8.ltoreq.y.ltoreq.1.2, 0.8.ltoreq.z.ltoreq.1.2 and 0.8.ltoreq.w.ltoreq.1.2, and if a, b and c all are not zero, i.e., greater than zero, a+b+c=1, d+e=1 and f+g=1, and 0&lt;a.ltoreq.1, 0&lt;b.ltoreq.1, 0&lt;c.ltoreq.1, 0.ltoreq.d.ltoreq.1, 0.ltoreq.e.ltoreq.1, 0.3.ltoreq.f.ltoreq.0.99 and 0.01.ltoreq.g.ltoreq.0.7; if b is zero, a+b+c=1, d+e=1 and f+g=1, and 0&lt;a.ltoreq.1, 0&lt;c.ltoreq.1, 0&lt;d&lt;1, 0&lt;e&lt;1, 0.3.ltoreq.f.ltoreq.0.99 and 0.01.ltoreq.g.ltoreq.0.7; if c is zero, a+b+c=1, d+e=1 and f+g=1, and 0&lt;a.ltoreq.1, 0&lt;b.ltoreq.1, 0.ltoreq.d.ltoreq.1, 0.ltoreq.e.ltoreq.1, 0.3.ltoreq.f.ltoreq.0.99 and 0.01.ltoreq.g.ltoreq.0.7; if d and e both are not zero, a+b+c=1, d+e=1 and f+g=1, and 0.ltoreq.a.ltoreq.1, 0.ltoreq.b.ltoreq.1, 0.ltoreq.c.ltoreq.1, 0&lt;d&lt;1, 0&lt;e&lt;1, 0.3.ltoreq.f.ltoreq.1.0 and 0.ltoreq.g.ltoreq.0.7.

Oxide superconductors

Growing community of inventors

Mito, Japan

Atsuko Soeta