Effect of Ag on the peritectic decomposition of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x}

During the melt processing of superconducting wires and tapes a number of partial liquid phase regions are entered, and the type and amount of second phases that exist in the melt before cooling are critical in determining the microstructure of the final material. Decomposition pathway of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x}(Bi2212) with 0, 2, and 10 wt% Ag added was examined at 1 bar PO{sub 2} by performing SAME/EDS analysis on oil quenched samples. A variety of quaternary phase diagrams were constructed to describe the evolution of the phase assemblage with temperature. At all Ag contents, Bi2212 first undergoes a peritectic reaction producing (Sr{sub 1-x}Ca{sub x}){sub 14}Cu{sub 24}O{sub 41}(14,24), Bi{sub 2}(Sr{sub 1-x}Ca{sub x}){sub 4}O{sub x}(24x), and liquid.