Enhancements in the transport current properties of long lengths of multifilament Ag-sheathed (Bi,Pb)_2Sr_2Ca_2Cu_2O_y (Bi-2223) superconducting tapes were achieved due to increased packing density of precursor powder, improved mechanical deformation, and adjusted cooling rate. Improved processing parameters had a pronounced effect on the transport critical current (I_c) of the superconducting tapes. At 77 K and zero applied magnetic field, an I_c of 60 A was obtained in short length samples (4 cm), an I_c of 54 A in a 164 m length, and 18 A in a 1,260 m length. Maximum critical current values were two to three times higher in slow-cooled tapes than in fast-cooled tapes.
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