Critical temperature, upper critical field and critical current relationships in as-reacted and mechanically treated (pre-bent) Nb_3Sn wires with different architecture

摘要

Si_xNb_3Sn composite wires (Furukawa Electric Co., Fig. 1) with different architecture (design and reinforcement) were compared from the normal state resistance R, critical temperatures (T_c)~(onset), (T_c)~(offset) and ΔT_c, upper critical field B_(c2) (at 4.2K) and critical current density J_c points of view. Wires were as follows: three of near-the-edge reinforcement design with Nb reinforcement of 0,21, 50 vol% in the CuNb region, and of central reinforcement design with Nb of 21 and 50vol%. One wire with 'near the edge' 50% vol Nb reinforcement had a different ratio reinforcement/superconductor (JR3).