Processing and fabrication of high-Tc superconductors for electric power applications

Abstract

Recent developments in the powder-in-tube fabrication of (Bi,Pb)2Sr2Ca2Cu30x tapes include identification of high-current-transport regions of the superconductor core, optimization of conductor design and processing to take advantage of these high-current regions, optimization of superconductor powders and heat treatments, and incorporation of flux-pinning defects into the superconductor grains. These developments are briefly discussed and their implications are assessed.?Current address:

Superconductors: Processing of High‐ T C Bulk, Thin Film, and Wires

“…The reaction kinetics and thermodynamics for synthesis of the pure Bi2223 phase are quite complex and generally result in mixed phase samples, with the presence of Bi2223, Bi2212, and other secondary phases. Partial substitution of lead for bismuth is generally found to stabilize growth of the Bi2223 phase with a typical starting composition of Bi:Pb:Ca:Sr:Cu given by 1.8:0.4:2:2:3 for such growth (50). Figure 21 pictorially shows the four steps involved for the OPIT method of preparing HTS wires and tapes.…”