Quality analysis of superconducting wire and cable for SSC dipole magnets: a comparison of recent performance and specification requirements

A critical component of the SSC (Superconducting Super Collider) dipole magnets is superconducting cable. The uniformity and reliability requirements for the dipoles place stringent demands on the cable. These needs have been defined as various contract requirements in the material specifications for NbTi alloy, superconducting wire, and cable. A supplier qualification program is being started by the SSC Laboratory (SSCL) with industry to establish reliable sources of superconductor cable. To monitor conductor performance, a computer database is being developed. The database focuses on the understanding and control of variation in the manufacture of wire and cable. A statistical and graphical summary of current data for key performance variables is presented in light of the specification requirement for uniformity. Superconductor material characteristics addressed include wire critical current, copper-to-non-copper ratio, wire diameter, wire piece-length, and cable dimensional control