Abstract
We applied the Bi-based oxide superconducting bulk to the current leads in a cryocooler-cooled superconducting magnet which is free from liquid helium in operation. The magnet is capable of generating a steady magnetic field of 4T at a current of 400A in room-temperature 38mm diameter bore.
Here we have investigated superconducting properties of Bi-based oxide bulk fablicated by intermediate cold isostatic pressing process. The bulk has a composition of (Bi+Pb): Sr:Ca:Cu=2:2:2:3 and is utilized in the form of thin-walled sintered cylindrical tube. The transport critical current density and critical current of the bulk at 77K under self-magnetic field are more than 1000A/cm2 and 1100A, respectively.