A metallurgical approach to high-Tc microcomposites

Since the discoveries of high-Tc superconducting oxides in the La-Ba-Cu-O system, the Y-Ba-Cu-O system, the Bi-Sr-Ca-Cu-O system and the Tl-Ba-Ca-Cu-O system, tremendous efforts have been made in the synthesis, processing and characterization of these materials in an effort to move toward applications. One of the methods for the synthesis of bulk superconducting oxides is high-temperature oxidation of metallic precursor alloys. Noble metals (e.g., silver) can be added to these alloys to produce microcomposites and improve mechanical properties. The content of the noble metals can be adjusted to alter the mechanical as well as superconducting properties of the products. Compared with conventional ceramic processes, the precursor oxidation method produces superconducting materials with variable shapes, high density and improved mechanical properties. The metallic precursor method can also provide joints between two superconductors or superconductors and normal metals