High strength, high conductivity macro- and microcomposite winding wires for pulsed magnets

Two promising types of Cu/SS macrocomposite and Cu-Nb microcomposite windin g wires for large-scaled high-field pulsed magnets are reviewed. The featur es of corresponding manufacturing processes for Cu/SS and Cu-Nb wires are p resented. It was shown that the manufacturing process designed for the fabr ication of composite multifilamentary low-temperature superconducting wires could be successfully applied for the production of high strength, high co nductivity Cu-Nb microcomposite conductors. The strength-conductivity prope rties of several types of Cu-Nb and Cu/SS conductors are given. The microst ructure of Cu-Nb microcomposite conductors has been investigated by means o f SEM and X-ray analysis. The influence of microstructural parameters on th e mechanical and electrical properties has been analyzed. The room temperat ure (RT) ultimate tensile strength (UTS) at the level of 900-1100 MPa and c onductivity 50-60% IACS for Cu/SS conductors with cross-sections up to 40 m m(2) have been attained. The strength-conductivity properties of several ty pes of Cu-Nb microcomposite wires with continuous and "in situ" formed disc rete filaments are presented. For Cu-Nb "in situ" wires with 6 mm(2) cross section the RT UTS exceeding 1400 MPa and conductivity similar to 60% IACS have been attained. (C) 2001 Elsevier Science B.V. All rights reserved.