AC losses in Ag-sheathed Bi2223 tapes with Ca2CuO3 as interfilamentary resistive barriers

Abstract

In this study, we prepared the Bi2223 multifilamentary tapes with Ca2CuO3 as interfilamentary resistive barriers and evaluated their AC magnetization loss properties at 77K. The Bi2223 tapes with thin barrier layers of Ca2CuO3 around the filaments were prepared by using a standard powder-in-tube (PIT) method. To fabricate the Ca2CuO3 layers around each filament, the outside surface of monocore Ag-sheathed wires was coated by Ca2CuO3 with the slurry. After the heat treatment to decompose and evaporate the organic binder in the slurry, the several coated monocore wires were stacked and packed into another Ag-tube. Then, the packed tube was drawn and rolled into tape shape. The tape was subsequently sintered to form Bi2223 phase inside filaments. The AC magnetization losses in an AC transverse magnetic field were measured by a pick-up coil method. The loss properties in the barrier tape were compared with those in the tape without barriers. The results indicated that introducing Ca2CuO3 barriers is very effective to suppress the electromagnetic coupling among the filaments and also to reduce the magnetization losses under parallel transverse field.