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The prebending strain effect on cabling conductors fabricated with high strength [Nb.sub.3]Sn wires and conventional [Nb.sub.3]Sn wires is evaluated by using a react-and-wind method. High strength [Nb.sub.3]Sn wire and the prebending strain effect are useful for developing the superconducting cabling conductors with large current capacity and high strength.

A study into the design and production of high temperature superconducting power transmission cable is reported.

The use of Nb3Sn wire for high field superconducting magnets and the selecton of an intermetallic compound as reinforcement is investigated.

A description of the high strength and high-RRR aluminum-stabilized superconductor for the ATLAS thin solenoid is provided.

The development of the ATLAS central solenoid magnet for the 2 Tesla is discussed. The design features high strength aluminum stabilized superconductor for stability.

The progress of the design and development of the ATLAS central solenoid magnet is described. The ATLAS central solenoid magnet is being built as a collaboration between CERN and KEK for the ATLAS experiment in the Large Hadron Collider (LHC) project. It is designed for providing an axial magnetic field of 2 Tesla in a warm-bore of 2.3 m in diameter for precise momentum measurement of charged particles generated in 14 TeV proton-proton interactions at LHC.

Thermo-mechanical treatment has been used in improving the Jc values and performance of Nb-Ti-Ta ternary alloy multifilamentatry superconducting wires. Results indicate that heat treatments produced critical current densities and upper critical fields between 4.2 K and 1.6 K degrees. The resulting J values were 1383 A per square mm and 602 A per square mm. The corresponding magnetic shift at the obtained values was approximately 4 T.

Super-GM has been developing 70MW class superconducting generators (model machines) for 200MW class pilot generator. Three types of NbTi conductors were developed for each of three model machines. Regarding to the high stability type conductors, residual resistance value of 6.5[[micro]ohms]/m was achieved by adopting Al stabilizer. Regarding to the high current density type, Ic of 13.8kA at 5T was realized by reducing void fraction in conductors and maintaining high residual resistivity ratio. For the low AC loss type, high Jc and low AC loss (8.1kW/[m.sup.3]) have been succeeded by applying strand insulation and two stage cabling. To confirm superconducting characteristics concerning long-term reliability, Ic and AC loss of each conductors were measured under 10,000 times repeated compressive force of 30MPa that is supposed in daily start and stop operation of generator for 30 years. In parallel to the R&D of NbTi conductors, R&D of [Nb.sub.3]Sn conductors were also conducted for enhancement of critical current density and critical magnetic field.

A double-stranded cable for use in the field winding of a 70-MW superconducting generator was characterized. Specifically, measurements of inter-strand resistance and ac losses were carried out on a formvar-insulated cable made of niobium-titanium, copper and copper-nickel wires. The results, which enabled correlations between inter-strand resistance and inter-strand coupling loss, revealed a larger strand deformation at the Z-S contact plane than in the Z-Z level.

The Akagi Testing Center of the Central Research Institute for Electric Power Industry has tested the superconductors developed for the rotor windings of a 200-MW superconductor generator. The facility has a special testing laboratory that can stimulate the mechanical and electromagnetic conditions of a rotor winding during operation. The tests quantified the critical current and ac losses of the superconductors during 10, 000 applications of a 30 MPa cyclic mechanically compressive load.