Electrical and superconducting properties of nanosize MgO added dip-coated Bi-2212 superconductor tape

The Bi₂Sr₂CaCu₂O₈ (Bi-2212) superconductor powder with 5% nanosize MgO addition was used to fabricate Bi-2212 tapes through the dip-coating-then-stacking method. In this method, the tapes were prepared by stacking layers of single side dip-coated silver strips, and then wrapping them with silver foil. The tape samples were rolled and pressed to increase the packing density of the superconductor core, and heat treated with partial melting temperature of 865°C for about 6 minutes. The fully processed tapes were investigated through the XRD patterns, dc electrical resistance measurements, SEM micrographs and transport critical current density (J_c). The addition of nanosize MgO tape samples enhanced the transport critical current density without affecting its transition temperature (T_c). This was attributed to the presence of MgO as pinning centers. Furthermore, the addition of nanosize MgO improved the microstructure and texturing of the tape sample without compromising their superconducting properties.