Processing and properties of the high T sub c superconducting oxide ceramic YBa sub 2 Cu sub 3 O sub 7

Conference · Wed Jul 01 00:00:00 EDT 1987 · Advanced Ceramic Materials; (USA)

OSTI ID:5097267

Bender, B; Wallace, J; Lewis, D ^[1]; Spann, J R; Lawrence, S ^[2]; Qadri, S ^[3]; Toth, L; Osofsky, M; Fuller, W; Skelton, E; Wolf, S; Fubser, D

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1. Naval Research Lab., Washington, DC (USA)
2. Crystal Growth and Material Testing Associates, Lanham, MD (USA)
3. Sachs-Freeman Associates, Landover, MD (USA)

The landmark discovery by Bednorz and Muller of a new class of superconducting materials in the lanthanum-barium (strontium)-copper oxide system with critical transition temperatures (T{sub c}) above 30K, sparked unprecedented interest among a great many workers in a wide range of research areas. The ensuing efforts to find materials exhibiting superconductivity at even higher temperatures led to the report by Chu and coworkers of a two phase oxide ceramic system exhibiting onset of superconductivity above 90K. Subsequent work which identified one of the phases, YBa{sub 2}Cu{sub 3}O{sub 7} (YBC), as the oxide responsible for superconductivity provoked a tremendous amount of research on this compound (although the search for materials with even higher T{sub c}'s continues unabated). The authors work, first with the Bednorz and Muller materials and more recently with YBC, has been directed primarily toward finding processing conditions leading to dense bulk and thick film materials while equaling or exceeding currently attainable superconducting properties. Toward this end they have sought to correlate processing parameters with microstructural and crystalline parameters and to provide high quality, well characterized samples suitable for detailed investigations of fundamental physical and superconducting properties. Of the various methods available for the preparation of high T{sub c} YBC, the one usually employed is as follows: (a) mix and grind appropriate proportions of BaCO{sub 3}, CuO and Y{sub 2}O{sub 3} predried powders; (b) calcine for 6-12 h at 900-950{degree}C in air with intermediate grindings; (c) grind and cold press into pellets (or other shapes); (d) sinter in air or flowing oxygen at 925{degree}C for about 12 h; (e) cool slowly in flowing oxygen at about 1{degree}C/min or hold between 500-600{degree}C for several hours.

• OSTI ID: 5097267
• Report Number(s): CONF-8704372-; CODEN: ACEME; TRN: 90-006866
• Journal Information: Advanced Ceramic Materials; (USA), Vol. 2:3B; Conference: Ceramic superconductors, Pittsburgh, PA (USA), 26-30 Apr 1987; ISSN 0883-5551
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BARIUM OXIDES
FABRICATION
MICROSTRUCTURE
PHYSICAL PROPERTIES
COPPER OXIDES
YTTRIUM OXIDES
CERAMICS
CHEMICAL COMPOSITION
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TRANSITION TEMPERATURE
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication
360202 - Ceramics
Cermets
& Refractories- Structure & Phase Studies
360204 - Ceramics
Cermets
& Refractories- Physical Properties
656100 - Condensed Matter Physics- Superconductivity