In situ x-ray investigation of the melting of Bi-Sr-Ca-Cu-O phases

Abstract
High‐temperature x‐ray studies of the melting of Bi2Sr2Ca1Cu2O8−δ/Ag composites have been undertaken in order to determine the factors that control the melting temperature and the various phases that form during the melt‐processing part of the fabrication of these conductors. During the melting process, three distinct phases form and then dissolve in the Bi‐rich liquid: first (Sr,Ca)1Cu1O2, then (Sr,Ca)2Cu1O3, and finally (Sr,Ca)O. Ag suppresses the melting point about 30 °C and as much as 10% Ag can dissolve in the Bi‐rich liquid. A slight Bi excess also decreases the temperature where the Bi2Sr2Ca1Cu2O8−δ structure disappears and liquid forms.