Growth Process of the (2223) Phase in Pb-Added Bi-Sr-Ca-Cu-O

The growth process of the (2223) phase in Bi-Sr-Ca-Cu-O has been studied for oxides with nominal composition Bi 2 Pb 0.6 Sr 2 Ca 2 Cu 3 O x prepared by sintering at 835∼855°C for 5∼160 h in air. The partial melting which starts to occur at T pm ≃842°C enhances the growth rate of the (2223) phase and produces a nearly single phase within 40 h. However, it causes a disturbance in current paths and suppresses the value of T c (ρ=0) below 100 K. The sample which has the highest T c (ρ=0) and the nearly single (2223) phase is obtained by sintering at a temperature just below T pm for a long period of time.