Nippon Steel Corporation

Kawasaki Jukogyo Kabushiki Kaisha

International Superconductivity Technology Center

Hokuriku Electric Power Company

Kawasaki Steel Corporation

Tosoh Corporation

Railway Technical Research Institute

Shoichi Kagiya

Masato Murakami

Naoki Koshizuka

Hiroshi Takaichi

Akihiro Kondoh

Shoji Tanaka

Hiroyuki Fujimoto

Naomichi Sakai

Naomichi Nakamura

A method for producing an REBaCuO oxide superconductor having large magnetic levitation force, where RE is a rare earth element selected from the group consisting of Y, Sm, Eu, Gd, Dy, Ho, Er, and Yb, involves the steps of using a raw material mixture as the starting feed, heating the raw material mixture for partial melting, followed by cooling and solidification, pulverizing and mixing the resulting solid, shaping the resulting mixture into a given shape, placing or embedding nucleates on or in the resulting shape, followed by heating for partial melting, and cooling the resulting partial melt to a substantial temperature at which a superconducting phase starts to form, followed by slow cooling, whereby the superconducting phase is preferentially formed and grown from a nucleation site.

Production of oxide superconductors having large magnetic levitation

To ensure a well-oriented crystal structure, there is provided a process of producing an oxide superconductor of a Y--Ba--Cu--O system with a composition having an atomic ratio Y:Ba:Cu of 1.0-2.0:2.0-2.5:3.0-3.5, the process comprising the steps of: preparing a semimelt including solid and liquid phases and consisting of Y, Ba, Cu and O in the atomic ratio; and solidifying the semimelt to form the oxide superconductor by so controlling a moving speed of a solidification front to have two components of different values in two perpendicularly intersecting directions.

Process of producing oxide superconductor

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Tokyo, Japan

Shoichi Kagiya