Showa Electric Wire & Cable Co., Ltd.

Kabushiki Kaisha Toshiba

General Director of National Research Institute for Metals

Tomoyuki Kumano

Masamitsu Ichihara

Satoru Murase

Nobuo Aoki

Hachio Shiraki

Eigen Suzuki

Kiyoshi Inoue

Tooru Hirota

Hiroshi Maeda

Akira Imai

Yoshimasa Kamisada

Yoshikazu Sakai

A method for producing a Cu--Ag alloy based conductive material containing about 10% to about 20% at % Ag, that involves the steps of continuously casting the alloy into a rod followed by quickly cooling the rod, cold-working the rod to a reduction in area of 80% or more, then heat treating the cold-worked rod at a temperature of 250.degree. C. to 350.degree. C. for 1 hour or more to form a heat-treated rod, and thereafter cold-working the heat-treated rod to a reduction in area of 90% or more as defined based on the cast rod to produce conductive material having a high strength of 700 MPa or more and conductivity of 75% IACA or more.

Method of producing Cu - Ag alloy based conductive material

An improved multifilament superconductor is fabricated by the method in which a tin rod or tin based alloy rod is clad with a copper based alloy tube, the thus obtained copper-clad rod is further clad with a niobium based alloy tube, and a copper material is applied as a stabilizer on an outer peripheral surface of the niobium based alloy tube to form a composite. This composite is then reduced and thermally treated at a temperature ranging from 640.degree. to 770.degree. C. to thereby form an Nb.sub.3 Sn superconductor composite with a filament tube therein. At least one of the copper based alloy tube and the niobium based alloy tube contains 0.1-5.0 at. % titanium, and in addition, the tin based alloy rod may contain 0.1-3.5 at. % titanium. The tin is contained in the copper-clad rod at weight % of about 25-85, preferably 30-80 weight %.

Method of fabricating multifilament superconductors

Growing community of inventors

Kanagawa-ken, Japan

Tomoyuki Kumano