High T_c superconductors: Melt processing and high flexibility composite conductor construction

This investigation in the technology of high temperature superconducting composite wires presents thermal expansion data gleaned from the dilatometer testing of cast ingots of YBa₂Cu₃O_x and Bi₂CaSr₂Cu₂O_y. Ingots were produced in a gas fired pot kiln and cast in steel molds.

This data is used in the design of wire form conductors made of the high temperature superconducting materials. Two benchmarking indices are defined, the Elastic Flexibility Index (E.F.I.) and the Conductor Area Efficiency (C.A.E.).

An expression is derived for the second area moment of a coaxial cylindrical composite beam using the method of transformed section. This expression is used to determine the E.F.I. of a prestressed composite wire design which shows a 700% increase in E.F.I. over any non-prestressed design.