Bi-2223 large sized magnetic shield prepared by jointing sintered bulks

In order to fabricate large sized superconductor plate shielding magnetic field above several mT, small pieces of sintered bulk were jointed with superconductor paste prepared with mixture of calcined powder and organic vehicle. Thirteen Bi-2223 four-cornered bulks were jointed superconductively to 40 mm(2) and 4 mm thick plate. The magnetic shielding property was measured at 77 K. Uniform magnetic field was applied perpendicular to the plate surface. Two-dimensional distribution of the magnetic Aux density over the sample surface was measured by a Hall prove parallel to the sample surface. When magnetic field of 15 mT was applied to the sample, the magnetic flux penetrated the sample along the jointed line. Magnetic shielding effect of the sample was observed uniformly with the external magnetic field of 10 mT. (C) 2001 Elsevier Science B.V. All rights reserved.