Electrical and magnetic properties of hot extruded Bi-2223/Ag concentric tapes

Summary

In this work we report on the anisotropic physical properties of silver-sheathed Bi-2223 tapes fabricated by means of hot extrusion and repeated pressing and sintering processes. The obtained Bi-2223/Ag short tapes, having critical current densitiesJ _c of 20–30 kA/cm² at 77 K, 0 T, were measured in external magnetic fields up to 0.5T applied in two different orientations (i.e. µ₀ H ∥ (a,b)-planes and µ₀ H ⊥ (a,b)-planes). The magnetic characterizations were performed in a wide range of temperatures and magnetic fields to study the first magnetization curve of tapes evaluating the lower critical fields µ₀ H _{c1 ∥a b} and µ₀ H _{c1 ⊥a b} and their dependences on temperature. TheJ _c values at different fields in the temperature range 4.6–90 K, calculated from the magnetization data by the critical state model, are also presented.