Scope and Purpose Although conductors based on the Al5 intermetallic compound Nb Sn 3 possess desirable high-field superconducting properties, manufacturing and handling difficulties, coupled with the tendency of their critical current densities to degrade rapidly under stress, have generally restricted their use to fairly straightforward, usually small-scale solenoidal-magnet applica tions. Likewise the Al5 compound VGa, which has a wider critical strain 3 window than NbSn but a uniformly lower upper critical field, has not 3 entered widespread service. Strain has been found to have no measurable influence on either the critical fields or the critical current densities of compound superconductors with BI and Cl5 crystal structures, but as yet they are still in the research and development stages. On the other hand, conductors using the binary alloy Ti-Nb or multi component alloys based on it, because of their relative ease of manufacture, excellent mechanical properties, and relatively low strain sensitivities, are now being pressed into service in numerous large-scale devices. Such conductors are being wound into magnets for use in energy storage, energy conversion (i. e., generators and motors), and high-energy particle detectors and beam-handling magnets. of cold-rolled or drawn Ti-Nb-alloy wire for superconducting The use magnet applications was first proposed in 1961. During the ensuing ten years, while progress was being made in the development of Cu-clad filamentary-Ti-Nb-alloy conductors, Ti-Nb and other Ti-base binary transi tion-metal (TM) alloys were being employed as model systems in the fundamental study of type-II superconductivity."

In less than two decades the concept of supercon In every field of science there are one or two ductivity has been transformed from a laboratory individuals whose dedication, combined with an innate curiosity to usable large-scale applications. In the understanding, permits them to be able to grasp, late 1960's the concept of filamentary stabilization condense, and explain to the rest of us what that released the usefulness of zero resistance into the field is all about. For the field of titanium alloy marketplace, and the economic forces that drive tech superconductivity, such an individual is Ted Collings. nology soon focused on niobium-titanium alloys. They His background as a metallurgist has perhaps given him are ductile and thus fabricable into practical super a distinct advantage in understanding superconduc conducting wires that have the critical currents and tivity in titanium alloys because the optimization of fields necessary for large-scale devices. More than superconducting parameters in these alloys has been 90% of all present-day applications of superconductors almost exclusively metallurgical. Advantages in use titanium alloys. The drive to optimize these training and innate abilities notwithstanding, it is alloys resulted in a flood of research that has been the author's dedication that is the essential com collected, condensed, and analyzed in this volume."