Filamentary A15 Superconductors

Compound superconductors with the Al5 structure carry the promise of the second generation in practical superconductivity. They will provide higher operating magnetic fields at higher tem- peratures than the preceding alloy superconductors. To fulfill this promise, their brittle nature must be accommodated in a fila- mentary structure. Achieving this has been no simple task and imaginative research and clever production techniques have led to many usable conductor configurations. In addition, several new and exciting possibilities are being proposed; for example, in situ processing promises easier production with improved strain toler- ance. It is timely, therefore, to take measure of what we have achieved and to assess our understanding so that we may choose, with some confidence, paths for future research and potential ap- plications. To meet these needs, the International Cryogenic Materials Conference Board has sponsored this special topic conference on Filamentary Al5 Superconductors bringing together superconductiv- ity researchers, superconducting wire producers, and high field magnet users to discuss current research problems. That the in- formation exchange was intensive and successful is evidenced by the excellent papers in this volume. In order to capture some of the synergistic wisdom generated in discussions at the conference several people were asked to assemble and interpret the comments and concerns of the fusion, high energy physics, solid state phys- ics, and metallurgy groups.