The metallurgical design of Nb-Ti and Nb3Sn multifilament superconductors

Although the metallurgical properties are only one of a number of important concerns in the design of a useful multifilament magnet conductor, they are of basic importance both to the fabrication process and to the critical current density Jc. In this paper we discus some of the implications of making certain metallurgical choices - for example in the Nb-Ti system high Jcmay be obtained over a range of alloy contents and for bronze route Nb3Sn conductors a variety of bronze to Nb ratios are chosen. Some of the consequences of the choice are explored with respect to the basic superconducting properties Tcand Hc2, the strongly structure sensitive property Jc, the fabricability and the mechanical stability.