Mechanical and superconducting properties of Nb₃Sn wires with Nb-rod-processed CuNb reinforcement

New Nb-rod-processed CuNb reinforced Nb3Sn superconducting wires have been developed for large high field magnet applications. The critical current, Ic, mechanical properties and resistivity are investigated. The residual strain and irreversible strain are found to be 0.35% and 0.77%, respectively. We found that the Nb-rod-processed wire has a large strain sensitivity to Ic. However, the wire has good mechanical properties, having a 0.2% proof stress of 280 MPa and a Young's modulus of 150 GPa. This means that the stress sensitivity of the Ic for the wire is small. These results show that the Nb-rod-processed wire is suitable as a strand of Rutherford cable for a high field superconducting magnet.