Developments in Nb3Sn forced flow conductors for large magnets

The production of a Nb3Sn forced flow conductor requires the development of the techniques for reliably fabricating long lengths of compacted cable in a stainless steel jacket. Development is needed in two major areas: 1) cabling and preliminary compaction of the cable and 2) wrapping, final compaction squaring of the full conductor. The configuration of the Nb3Sn strand is presented and its performance characteristics are described. Early investigations have been made using handmade cables and the sample length was limited to 5 m by the compaction techniques used at the time. Machine made copper cable has been completed and differences are also described. Finally developments in the continuous wrapping and compacting process will be discussed.