Fabrication of multifilamentary Y-Ba-Cu-O oxide superconductors

Workability of Y-Ba-Cu-O composite wires with a Ag sheath has been studied and multifilamentary Y-Ba-Cu-O superconductors with a Ag matrix have been successfully fabricated. Observations of the wires with a scanning electron microscope reveal that as the areal reduction ratio R increases, the average Y-Ba-Cu-O grain size decreases. The study on the workability of the composite wires reveals that composite wires consisting of the Y-Ba-Cu-O powder and a Ag matrix can be rolled or drawn to any extent by a cold-work process with intermediate annealings at 150 0C for R = ∼10. Based on this study, we have succeeded in fabricating a 252 filament Y-Ba-Cu-O wire which shows a T/sub c/ (onset) of ∼95 K