Authors: Aruchamy, A.; Kim, S.J.; Birnie, D.P. III; Uhlmann, D.R.
Source: Journal of Non-Crystalline Solids 160 (1993) 60-67

Abstract: Microstructure and phase development of as-quenched and annealed samples of the glass of composition Pb_0.32Bi_1.68Sr_1.75Ca₂Cu₃O_x have been studied. Evidence for liquid-liquid phase separation during quenching was found. The microstructure of this glass during the early stage of crystallization is similar to that found for Bi₂Sr₂CaCu₂O_x (2212) glass. The first phase that crystallizes on annealing at low temperatures appears to be Cu₂O. In further heat treatments the sequential crystallization of the R-phase of (Pb_yBi_2-y)Sr₂CuO_x  ('2201') composition and the  (Pb_yBi_2-y)Sr₂CaCu₂O_x  ('2212') phase was found, in agreement with other studies. Phase separation determines the initial crystal phase and the development of the superconducting phases. Phase separation observed in this glass points to the possibility that immiscibility may be a common feature of a wide range of Bi(or Pb-Bi)-Sr-Ca-Cu-O compositions.