High electrical performance Ag-sheathed Bi-2223 multifilamentary tapes prepared by an optimised PIT processing route

An optimised PIT processing route is introduced and discussed gained from e xperiments investigating the effect of processing on microstructure, and su bsequently on Jc in PIT tapes. At 77K and self-field, the highest Jc perfor mance of 51,000A/cm(2) has been obtained for 69-filamentary tapes. High cri tical current samples with Ic=108A and Jc=36,000A/cm(2) have been measured at 77K and self-field for 361-filament tapes. Our results indicated that Jc is influenced on Pb distribution of Pb-2212, phase composition for the pre cursor powder, the deformation reduction rate, and the core thickness. Inte rmediate processing (cooling, deformation and heating) between thermal-mech anical cycles and finally cooling procedures also play an important role on Bi-2223 phase purity and achievement of such high electrical performance i n the tapes.