Phase characterization in three monofilament BSCCO 2223/Ag tapes

The nonsuperconducting (non-SC) phases present in three BSCCO (Bi-Sr-Ca-Cu oxide) tapes have been identified. These tapes were obtained from precursor powder produced by three different routes and the microstructural characterization was conducted using scanning electron microscopy and X-ray diffraction. The phases: alkaline earth cuprate (Ca,Sr)2CuO (AEC 2:1), CuO and a Pb-rich phase (CaPbO4+(Pb,Bi)3Sr2Ca2CuOx) were quantified using an imaging analyzer software on a cross-section after 50, 110, 170 and 230 h exposures at 820°C, which were performed between mechanical pressing operations. The correlation between critical current density (Jc) and non-SC phases showed that there is no direct correlations between the global quantity of non-SC phases and Jc. Moreover, a good performance appeared to be highly dependent on many other factors, such as texture alignment and non-SC distribution.