A Hydrostatic Processing Facility for Superconducting Wire

72984S03-I Currently available methods impose limits on the processing of multi-filamentary, superconducting wires used in high energy physics experiments. These limits can be severe when one of the wire components has a mechanical strength substantially smaller than the other component(s), and can eliminate many desirable wire designs from consideration. Niobium-Tin and Niobium-Aluminum are examples of systems that exhibit this problem. Recent experimental work has shown that hydrostatic reduction, using low-angle dies and relatively large-area reductions (greater than 4:1), can produce good results with a much wider range of material mechanical strengths; in particular, jelly roll structures including niobium, copper, and tin have been processed successfully. Yet, when these same systems were processed using cold drawing, the results were unacceptable. Based on these results, this project will develop new wire architectures that can produce high current densities (> 3,000 A/mm2 @ 4.2K and 12T) with small effective filament diameters (< 10 microns) in Niobium-Tin superconductors. Hydrostatic processing, with high area reductions per pass, will be used for all processing, from the initial billet to the final wire size. In Phase I, a hydrostatic facility for processing wire-sized material will be designed. The wire will be coiled in a relatively large-inside-diameter pressure vessel (6¿<ID<12¿) that has a high working pressure (~ 150,000 psi). This wire processing facility will be the last component of a Prototype Hydrostatic Processing Facility (PHPF). Commercial Applications and Other Benefits as described by awardee: The PHPF should allow for the production of Niobium-Tin and Niobium-Aluminum superconductors that meet the requirements of the DOE Conductor Development Program. The facility also would be available for use by others on a ¿toll¿ basis.