The Continuing Utility and Potential of Nb-based Superconducting Composite

Exciting developments continue to go on for HTS conductors and cables, including those based on ReBCO, Bi:2212 and 2223, MgB₂, and the pnictides. On the other hand, Nb-based superconductors, including NbTi, Nb₃Sn, Nb₃Al, continue in their utility and have continuing potential. NbTi conductors, are in fact the backbone of commercial superconducting technologies, with MRI (and NMR) an outstanding example of commercial success, and various particle accelerators their technological success. These conductors will continue to be used wherever and whenever they can be, because they are cost effective, mature, and convenient (except for the cooling!), Nb₃Sn conductors, continue to have potential for the next generation of accelerator magnets as the most cost effective and practical solution for achieving the needed performance, and even if supplemented by HTS inserts, they will be crucial aspects of the machine, keeping them viable both technically and cost-wise. Recent advances in these conductors are quite exciting and performance continues to increase for this well-known conductor. Nb₃Sn as well as Nb₃Al may still have a role to play in fusion. While great excitement has developed over compact fusion reactors, the future fusion reactors will need to be commercially as well as technically viable, and Nb₃Sn and Nb₃Al are of interest for hybrid and cost-effective magnets. LTSC conductor, especially those based on Nb, will continue to be of interest for machine and application development for some time to come.