Investigation of multifilamentary Nb3Sn strand for ITER by internal Sn process

摘要

By internal Sn process we have successfully fabricated the multifilamentary Nb3Sn strand with a diameter of 0.79 mm, which has 5616-6270 filaments. A two-step heat treatment was used for the Nb3Sn strands. The first step is related to bronzing process between Cu and Sn at a temperature range of 200-600 degrees C, whereas the second step for the formation of superconducting Nb3Sn phase at 600-800 degrees C. A non-Cu J(c) (12 T, 4.2 K) value of 1087 A/mm(2) has been obtained. The microstructure and transport property of strands have been discussed. (c) 2006 Elsevier B.V. All rights reserved.