Fundamental studies of shock-wave-induced degradation of superconductivity in explosively fabricated, bulk, metal-matrix, copper oxide, high-temperature superconductors

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1991

OSTI ID:6916972

Niou, Chornyg-Shyr

Explosive fabrication involves the simultaneous consolidation and encapsulation of superconducting powders within a metal-matrix monolith. However, the residual superconducting properties are found to be degraded as a result of the shock-wave pressure effect. In this study shock pressure varying from 4 GPa to 19 GPa revealed that the degradation of superconductivity increased with increasing peak pressures, and exhibited a steep increase in normal-state resistance (resistance-temperature or R-T curve) and broad superconducting resistance transitions, with decreasing critical temperature. Complete recovery of superconductivity could be achieved for all shock-loaded or explosively fabricated Y-Ba-Cu-O materials above 930[degree] C, and above 860[degree] C for Bi-Pb-Sr-Ca-Cu-O. Detailed kinetic studies on Y-Ba-Cu-O revealed a two-stage recovery process having different activation energies which were also sensitive to the peak pressure, and therefore to the densities of defects. In the context of the experimental results, a materials engineering strategy was investigated for optimizing the explosive fabrication of superconducting monoliths.

• Research Organization: Oregon Graduate Inst. of Science and Technology, Beaverton, OR (United States)
• OSTI ID: 6916972
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360207* -- Ceramics
Cermets
& Refractories-- Superconducting Properties-- (1992-)
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
EXPLOSIVE FORMING
FABRICATION
HIGH-TC SUPERCONDUCTORS
LOSSES
MATERIALS
MATERIALS WORKING
MATRIX MATERIALS
METALS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SHOCK WAVES
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS