Fabrication of Bi-(Pb)-Sr-Ca-Cu-O mono- and multifilamentary superconductors and improvement in critical current density

Journal Article · Fri Sep 15 04:00:00 EDT 1989 · Journal of Applied Physics; (USA)

DOI:https://doi.org/10.1063/1.344201· OSTI ID:5555694

Sekine, H; Inoue, K; Maeda, H ^[1]; Numata, K ^[2]

---

1. National Research Institute for Metals, 1-2-1, Sengen, Tsukuba City, Ibaraki 305, Japan (JP)
2. Advanced Technology Research Center, Mitsubishi Heavy Industries, Ltd., 1-8-1, Sachiura, Kanazawa-ku, Yokohama, Japan

The Bi-(Pb)-Sr-Ca-Cu-O superconductor has been fabricated into tapes without sheathing and into multifilamentary wires and tapes with Ag sheathing. Metallurgical studies as well as measurements have been made for them. Tape specimens prepared by combination and repetition of cold work (or cold press) and sintering showed critical current density {ital J}{sub {ital c}} as high as 5{times}10{sup 3} A/cm{sup 2} at 77 K with good reproducibility and reliability, although these specimens are sufficiently thick (0.5--1.0 mm). (Generally, {ital J}{sub {ital c}} at zero field is inversely proportional to thickness.) For these tape specimens (with Cu sheath), sintering and {ital J}{sub {ital c}} measurement were performed after the Cu sheath was removed. X-ray analysis showed that most of these tape specimens consist purely of high-{ital T}{sub {ital c}} phase ({similar to}107 K). In these specimens, the {ital c} axis tends to align well. This {ital c} axis alignment as well as compacting effect may be a cause of the enhancement in {ital J}{sub {ital c}} . On the other hand, the tape specimens cold-worked and sintered only once (not repeated) showed {ital J}{sub {ital c}} as small as only 10{sup 2} A/cm{sup 2} with the {ital c} axis showing no sign of alignment. A 1330-filament Bi-Pb-Sr-Ca-Cu-O wire with a Ag sheath has been successfully fabricated. This multifilamentary wire shows critical temperature {ital T}{sub {ital c}} of {similar to}105 K. A multifilamentary tape specimen fabricated by a combination of cold work and sintering showed {ital J}{sub {ital c}} of 1.05{times}10{sup 3} A/cm{sup 2} at 77 K.

• OSTI ID: 5555694
• Journal Information: Journal of Applied Physics; (USA), Journal Name: Journal of Applied Physics; (USA) Vol. 66:6; ISSN 0021-8979; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
BISMUTH COMPOUNDS
BISMUTH OXIDES
CALCIUM COMPOUNDS
CALCIUM OXIDES
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRITICAL CURRENT
CURRENTS
DIFFRACTION
ELECTRIC CURRENTS
FABRICATION
FILAMENTS
LOW TEMPERATURE
METALLURGY
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SCATTERING
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
WIRES
X-RAY DIFFRACTION