Microstructure and electrical properties of BSCCO tapes with ceramic barriers

The AC-losses in multifilamentary tapes can be reduced mainly by insulating barriers and/or by twisting. We prepared multifilamentary Bi-2223/Ag tapes with the PIT process using monofilaments dip-coated with a ceramic barrier (BaZrO/sub 3/, YSZ, CeO/sub 2/). All tapes with ceramic barriers showed, besides lower losses, a degradation of the critical current density due to interactions between the barrier material and the BSCCO-filaments during heat treatment. Furthermore, we studied the influence of the twist pitch on the AC-losses and the critical current density of twisted tapes without barriers. Microstructural investigations showed a partial damaging of the inner filaments during flat rolling.