Laser float-zone growth of superconducting Bi-Sr-Ca-Cu-O fibers: Characterization and phase equilibria

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

OSTI ID:5399797

Kim, Cheol Jin

Superconducting fibers in the Bi-Sr-Ca-Cu-O system were grown using the laser-float-zone method. The effect of growth rate and the starting-feed rod composition were studied by using XRD, SEM, EDS, TEM, DTA, and optical microscopy. Homogeneous superconducting fibers were obtained from feed rods with the nominal composition of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} ( 2212') using slow growth rates ({le}5 mm/h). The (Sr,Ca)CuO{sub 2} solid solution was prevalent when fast growth rates or feed rods with the Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+{delta}} ( 2223') composition were used. Annealing of the as-grown fibers above 800C for more than 12 hours was effective in reducing the fraction of 1{times}1 phase. {Tc}{sub mid} of the as-grown fibers was {approximately} 80K and annealing of these fibers lowered the normal state resistivity. Together with the fiber growth, a phase-equilibria study was conducted in an attempt to understand the crystallization behavior of the phases in the LFZ fibers.

• Research Organization: Case Western Reserve Univ., Cleveland, OH (United States)
• OSTI ID: 5399797
• 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-)
ALKALINE EARTH METAL COMPOUNDS
BISMUTH COMPOUNDS
BISMUTH OXIDES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL GROWTH
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
FABRICATION
FIBERS
HIGH-TC SUPERCONDUCTORS
OXIDES
OXYGEN COMPOUNDS
PHASE STUDIES
PHYSICAL PROPERTIES
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTIVITY
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE