(Nb,Ti)3Sn/CU Multifilamentary Superconducting Wire with Nb/Ti and Nb/NbTi Composite Filaments
Ternary (Nb,Ti)3Sn/Cu multifilamentary high-field superconducting wires with Nb/Ti and Nb/NbTi composite filaments were fabricated via a bronze-route process. The composite filaments, which contain about 1.3 wt.% Ti, were prepared from pure Nb and Ti sheets, or pure Nb and Nb47Ti alloy sheets using a jelly-roll technique. The ternary Al 5 superconducting phase is formed during final heat treatment by diffusion of Sn and Ti through matrix and filaments respectively, and then reaction with Nb. This new approach is designed to improve the workability and piece length as well as to reduce the cost of manufacturing (Nb,Ti)3Sn/Cu superconducting wires. A two-stage reaction heat treatment schedule has been developed to generate high Jc for these ternary A15 superconductors with composite filaments. Non-Cu Jc(12T,0.1μV/cm,4.2K) of~ 670A/mm2 was recorded on the wire with Nb/Nb47Ti composite filaments fabricated using this technique.
KeywordsCritical Current Density High Magnetic Field Alloy Filament Composite Filament Nb47Ti Alloy
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