A characterization of internal-Sn Nb3 Sn superconductors for use in the Proof of Priciples (PoP) coil

High-performance, Ti-alloyed, internal-Sn superconductors have been selected for use in the the Proof of Principles (POP) coil, a 1.0-m o.d., 0.4-m i.d. solenoid designed to produce fields up to 15 T. The POP coil, which will use forced-flow Cable-In-Conduit Conductors (CICC), will operate at 4.2 K and moderate levels of conductor strain. Here we report the results of detailed characterizations of two proposed POP coil Nb3Sn 19 subelement superconducting wires of differing topology. We have investigated the critical current as a function of applied field and applied strain. The wires were found to have excellent high-field properties, providing a high performance margin for the proposed POP coil. The field and strain dependence of Jc have been found to compare favorably with predictions from a wire performance model recently developed for NbgSn superconductors.