Development of Superconducting High Current Density Large Diameter Internal Tin (Nb3Sn) Wires
A class of large diameter internal tin wires have been developed which carry over 900 Amps at a wire diameter of 1.8 mm, 4.2 K, 14 T. Historically high current density (Jc (10T, 4.2K) > 2000 A/mm2) internal tin wires have been limited to smaller wire diameters. We report critical current and magnetization results on a wire design tested from 1.8 mm to 0.5 mm diameter. At smaller wire diameters the Modified Jelly Roll (MJR) element size drops below 20 µm. The small MJR elements result in a small deff which has the potential to meet the ITER specification in a wire that has a Jc in excess of 1400 A/mm2 at 12 T, 4.2K.
KeywordsCritical Current Density Wire Diameter Filament Thickness Element Diameter Jelly Roll
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