Influence of the mould temperature on the properties of melt-cast Bi-Sr-Ca-Cu-O precursors

The melt casting route has been shown to be a promising synthesis technique for the fabrication of bulk Bi-Sr-Ca-Cu-O superconductor. Precursors produced via this technique may be converted into superconducting material through conventional radiative heating or, as has been shown, through direct electrical resistance heating. For processing via the latter technique, a precursor with homogeneous electrical properties is preferred. In this paper melt cast precursor rods of composition Bi/sub 1.6/Pb/sub 0.4/Sr/sub 2/Ca/sub 3/Cu/sub 4/O/sub y/ have been prepared through casting a melt into a preheated copper mould and the influence of the temperature to which the mould was preheated on the electrical resistance and homogeneity of the precursor was studied.<>