BSCCO-2223 AG-SHEATHED TAPES PRODUCTION

The activity of the Superconductors Division of Europa Metalli S.p.A. in the field of HTS is mainly devoted to the production of long unit l engths of BSCCO-2223 Ag-sheathed tapes which are used for the realizat ion of small pancake magnets and are obtained by means of the OPIT tec hnique and subsequent drawing and rolling plastic deformation procedur es. Several mono-and multi-filamentary layouts were investigated in or der to optimize the electrical properties and minimize degradations du e to winding. At present the best results have been obtained with a mu lti-filamentary geometry, which shows higher critical currents and low er degradations with respect to the mono-filamentary geometry and cons equently proves more suitable for the production of small pancake magn ets. Once heat treated, a standard characterization is carried out on short samples, consisting in electric critical current measurements at 77 K in zero field and at 4.2 K in an external magnetic field up to 1 2 T to investigate the transport properties, and in AC susceptibility measurements at 77 K to determine the effectiveness of the thermal hea t treatment on the formation of the BSCCO-2223 phase.