EFFECTS OF COMPLEX PROCESSINGS ON CRITICAL-CURRENT DENSITY OF BI-2223TAPES

Some long-length Bi(Pb)-2223 tapes produced using the PIT technique an d multilayered structure technique have been developed for an industri al material for which the requirement is the J(c)= 30 kA cm(-2) class at 77.3 K in long-length wires. For this purpose, we have achieved rec ent progress in performance, such as reproducibility of the J(c) = 20 kA cm(-2) class at 77.3 K and low magnetic fields for long-length tape s having sound filaments, overall critical current density of 10 kA cm (-2) in a low silver:superconductor ratio tape, allowable strength of more than 100 MPa using silver alloy sheath and low AC loss of less th an 0.3 W kA(-1) m(-1) in kA class conductors using twisted wires.