The influence of precursor preparation on the superconducting properties of Bi(2223) tapes

This is the authors' abstract. We don't add key points for this paper.

The effect of preparation of precursor powders on the formation of Bi-2223 phase and critical current density (J/sub c/) of OPIT tapes, was studied. The precursors were prepared by "one-powder" and "two-powder" methods. The results indicate that a sufficiently large fraction of second phases in the precursors is crucial for obtaining pure 2223 phase and high J/sub c/ values. It is also revealed that the (Sr,Ca)/sub 2/CuO/sub 3/ second phase promotes a faster phase transformation of 2212 to 2223 than other second phases in the precursors. Tapes prepared with "one-powder" precursor achieved J/sub c/ of 25.5 kA/cm/sup 2/, while the J/sub c/ for the tapes made from "two-powder" precursors had values of about 12 kA/cm/sup 2/.