Consolidation of Bi-Sr-Ca-Cu-O superconductors by the shock-loading method

Abstract

Shock compaction experiments were carried out for Bi2223 to prepare a dense, oriented bulk specimen. The shocked specimen exhibited a high degree of crystallographic orientation and a high density, above 96%. The optimal condition of the crystallographic orientation was attained at a shock pressure of 5 GPa and at annealing temperatures between 750 and 800 • C. The post annealing of a specimen shocked at 5 GPa was effective in increasing M, indicating the introduction of pinning sites. The magnetic torque measurements showed that a high degree of orientation was attained and many pinning centres were induced by the shock loading.

Pressure Dependence of Crystal Growth in a Bi-Pb-Sr-Ca-Cu-O Superconductor Prepared by Shock Compression

“…Bi-Pb-Sr-Ca-Cu-O superconductors are fabricated by the shock compression method in order to establish a technique for higher-quality synthesis-larger crystal grains, predominance of the (BiPb) 2 Sr 2 Ca 2 Cu 3 O x (Bi-2223) phase and better T c -Bi-based oxide superconductors. Conventionally, shock-compacted Bi-based oxide superconductors are prepared under shock pressure of around 10 GPa [5][6][7]. In this research, starting materials were shock-compacted around 20 GPa and 30 GPa to reveal pressure dependence.…”

Anisotropic grain connectivity in shock consolidated MgB2bulk samples

“…This is because, during the processing of the wires, the hard sheath hands over external pressures directly to the MgB 2 powders packed in the metal tube, and hence high grain connectivity is achieved. One of the methods for generating high pressures, shock loading, has already been applied to high critical temperature (T c ) superconductors [6,7]. In high-T c bulk superconductors, weak links at grain boundaries have been a predominantly important subject [8].…”