EFFECT OF P(O-2) AND AG CONTENT ON THE DECOMPOSITION PATHWAY OF BI2SR2CACU2OX

The decomposition pathway of Bi2Sr2CaCu2Ox (Bi2212) with 0, 2 and 10 w t.% Ag added has been examined at 0.01, 0.21, and 1 bar P(O-2) by perf orming scanning electron microscopy with energy dispersive spectroscop y (SEM/EDS) and microprobe analysis on oil quenched samples. A series of pseudo-ternary phase diagrams at each P(O-2) was constructed to des cribe the evolution of the phase assemblage with temperature. Ag showe d limited solubility (2-3 wt.%) in the ceramic melt which depressed th e reaction temperature of each step along the decomposition pathway. T he first solid phases to form upon the peritectic decomposition of Bi2 212 were Bi9Sr11Ca5Ox (9115) and (Sr1-xCax)(14)Cu24O41 (14,24) in 1 ba r O-2, (9115) and (Sr1-xCax)CuO2 (11) in 0.21 bar O-2, and (11), (Sr1- xCax)(2)CuO3 (21) and Bi-2(Sr1-xCax)(3)O-x (23x) in 0.01 bar O-2.