Fabrication and Properties of High-Temperature Superconducting Wire by the Green-Fiber Method

Continuous Ag-clad YBa sub 2 Cu sub 3 O sub 7--x (Y-123) wire has been fabricated from cofired green fibers produced by melt-spinning polymers loaded with Y-123 powders (e.g. SPP-YZ). Metal claddings are provided by coating with Ag-alloy powder slurries. The sintered polycrystalline Y-123 wires have 77K self-field critical current density (J sub C ) values up to 2900 A /cm exp 2 , with typical ranges in long lengths of approx 1000 A /cm exp 2 , but are weak linked. High-J sub c wire is made by continuous melt texturing of the presintered wires. Values of J sub C > 10 000 A/cm exp 2 at 77K have been achieved.