PURE BENDING STRAND TEST OF HIGH PERFORMANCE Nb3Sn WIRES

A pure bending test device for characterizing the critical currents of superconducting strands has been developed for high-current superconducting wire tests. The device makes it possible to apply bending over a large range of strains on a strand sample that is subject to large electromagnetic forces, which are generated by the background magnetic field and the transport current. This device is able to change the bending strain of a 0.8 mm diameter sample up to 0.9% in liquid helium. Pure bending behaviors of recent high performance Nb3Sn wires have been tested.