A new facility for investigation on neutron irradiation effect on superconducting properties of Nb3Sn strand for fusion magnet

To perform post irradiation tests of superconducting strands, a 15.5 T superconducting magnet and a variable temperature insert (VTI) were installed at a radiation control area in Oarai center, Institute for Materials Research, Tohoku University. Both of the 15.5 T magnet and the VTI are conductively cooled with GM refrigeration. The commissioning test of the system is still ongoing because unexpected troubles occurred during the commissioning. Also, a SQUID system with the maximum field of 7 T has been installed at another radiation control area to investigate the magnetic property of uranium and its isotopes. These devices are very useful to study the electro-magnetic properties of the neutron irradiated superconducting strands. This paper will introduce the new superconducting test facility, and some data recently obtained will be presented together with the data of magnetization evaluated with the SQUID, and the discussion on the irradiation effect on superconducting properties will be performed.