Limits and descriptions of primary phase volumes in BSCCO

Our research group has conducted numerous phase equilibrium studies on the BSCCO system. BSCCO contains 6 binary edges and 4 ternary faces. Our earlier studies have focused on these subsystems. Sufficient information from our studies and the literature on these systems and sections through the quaternary is now available to develop a complete model of the quaternary system. Our current BSCCO model is based on projections from these known binary and ternary relations toward known quaternary relations. Theory, experiment, and published literature provided considerable constraints in developing this model. Most of the quaternary is occupied by primary phase volumes (ppvs) of (Sr,Ca)O and CuO, separated by ppvs of alkaline earth cuprates. Ppvs of bismuth rich phases generally do not extend far beyond the composition of the relevant crystalline phase. A limited volume containing ppvs of ternary and quaternary cuprates is situated between these ppvs. This volume has been chemographically located and neighboring ppvs determined. The (Sr,Ca)O and CuO saturated surfaces are documented in this study along with the extents of several ppvs emanating from primary phase fields on ternary faces.