Superconducting Bi sub 1. 5 Pb sub 0. 5 Sr sub 2 Ca sub 2 Cu sub 3 O sub x ceramics by rapid melt quenching and glass crystallization

Journal Article · Wed Aug 01 00:00:00 EDT 1990 · Journal of Applied Physics; (USA)

DOI:https://doi.org/10.1063/1.346709· OSTI ID:6729492

Bansal, N P ^[1]

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1. National Aeronautics and Space Administration, Lewis Research Center, Cleveland, Ohio 44135 (USA)

A glass of nominal Bi{sub 1.5}Pb{sub 0.5}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub {ital x}} composition, prepared by rapid quenching of the melt, showed a glass transition temperature of 383 {degree}C, crystallization temperature of 446 {degree}C, melting temperature of 855 {degree}C, and bulk density of 5.69 g/cm{sup 3} in air. The activation energy for crystallization of the glass has been estimated to be 292 kJ/mol from nonisothermal differential scanning calorimetry. On heating in oxygen, the glass showed a slow and continuous weight gain starting at 530 {degree}C which reached a plateau at 820 {degree}C. The weight gained during heating was retained on cooling to ambient conditions indicating an irreversible oxidation step. The influence of annealing conditions on the formation of various phases in the glass has been investigated. The Bi{sub 2}Sr{sub 2}Ca{sub 0}Cu{sub 1}O{sub 6} phase crystallized out first followed by formation of other phases at higher temperatures. The high-{ital T}{sub {ital c}} phase, isostructural with Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10}, was not detected below 840 {degree}C, but its fraction increased with the annealing time at 840 {degree}C. A sample annealed at 840 {degree}C for 243 h in air and furnace cooled showed the highest {ital T}{sub {ital c}}({ital R}=0) of 107.2 K and a narrow transition width, {Delta}{ital T}{sub {ital c}} (10%--90%), of 2 K. The high-{ital T}{sub {ital c}} phase does not seem to crystallize out directly from the glass but is rather produced at high temperature by reaction between the phases formed at lower temperatures. The kinetics of 110-K phase formation was sluggish. It appears that the presence of lead helps in the formation and/or stabilization of the 110-K phase.

• OSTI ID: 6729492
• Journal Information: Journal of Applied Physics; (USA), Vol. 68:3; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BISMUTH OXIDES
MELTING
CALCIUM OXIDES
COPPER OXIDES
LEAD OXIDES
STRONTIUM OXIDES
ANNEALING
CHEMICAL REACTIONS
GLASS
HIGH-TC SUPERCONDUCTORS
QUENCHING
TRANSITION TEMPERATURE
ALKALINE EARTH METAL COMPOUNDS
BISMUTH COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
HEAT TREATMENTS
LEAD COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
STRONTIUM COMPOUNDS
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies
656100 - Condensed Matter Physics- Superconductivity