E. Diazvaldes et al., EFFECT OF LEAD CONTENT ON NONSTOICHIOMETRIC BI2-XPBYSR2CA2CU3O-DELTA CERAMIC SUPERCONDUCTORS, Materials chemistry and physics, 36(1-2), 1993, pp. 64-67
Ceramic superconducting samples of the type Bi2-xPbySr2Ca2Cu3Odelta we
re processed with a nonstoichiometric content of Bi and Pb (x not equa
l y) with respect to the 2223 phase in this system. The resistance vs.
temperature characteristics and the presence of the 2223 and 2212 pha
ses as a function of the sample preparation conditions and the lead co
ntent (Bi/Pb ratio) are reported. The growth of unwanted phases such a
s PbO was observed for those samples with a high content of Pb (y=0.9)
and Bi (x=0.1).