Fundamentals of the preparation of high‐T_C, superconducting (Bi,Pb)_2+XSr₂Ca₂Cu₃O_10+δceramics

For the 2223 phase of the BiPbSrCaCuO superconductor, detailed knowledge of the phase relations and the homogeneity region are essential to the understanding of the fundamental issues influencing the processing of the materials. A six‐component system such as this would require a six‐dimensional phase diagram. Several ways to simplify the task to manageable dimensions, and the information one can obtain from a detailed investigation of this system are discussed.