Amorphous Superconducting Transformation in Bismuth-Base High-Tc Superconducting Rods

The transformation of high-resistivity amorphous (Bi1.68Pbo.32)Sr1.75Ca1.85Cu2.85Oy and (Bi1.6Pbo.4)Sr1.7Ca2.3Cu3Oy to superconductive materials has been characterized by structural, thermochemical, transport, and scanning electron microscope measurements. X-ray powder diffraction confirmed that rapid solidification of Bi-Pb-Sr-Ca-Cu-Oy yields amorphous material. In further heat treatments, sequential crystallization of three phases was identified.