Fabrication of Ag-Sheathed Ba-Y-Cu Oxide Superconductor Tape

Ba 2 YCu 3 O 7-δ tapes were fabricated by cold rolling. The critical current density J c apparently depended on the thickness of the tape and increased markedly with decreasing tape thickness. The maximum J c of 3330 A/cm 2 at 77 K in a zero magnetic field was achieved in an Ag-sheathed BYCO tape, 0.06 mm in thickness. The presence of a 20 mT magnetic field reduced the J c value by 1/100.