Granularity, microstructure, and flux creep in TlBa2Ca2Cu3O9+δ superconducting powder and silver-sheated tapes

Kung, P.J.; Wahlbeck, P. G.; McHenry, Michael E.; Maley, M. P.; Peterson, D. E.

doi:10.1016/0921-4534(94)90917-2

Cited by 23 publications

(9 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For all powder assemblages, the tapes were weak linked and J c decreased significantly upon application of a small external field. The J c results are similar to results reported for other work on Tl-1223 PIT conductors [20][21][22].…”

Section: Resultssupporting

confidence: 89%

Liquid phase sintering and microstructure development of Ag-clad Tl-1223 superconductor

Hagen

Kupperman

Goretta

et al. 1996

Supercond. Sci. Technol.

View full text Add to dashboard Cite

The phase evolution and electrical properties of Tl-1223 tapes were explored near the incongruent melt temperature. Liquid phase evolution was monitored as a function of time and temperature by an acoustic velocity monitor. The phase development kinetics for Tl-based superconductors are more than one order of magnitude faster than the kinetics of Bi-based superconductors. Three separate powder mixtures (Tl

show abstract

Section: Resultssupporting

confidence: 89%

Liquid phase sintering and microstructure development of Ag-clad Tl-1223 superconductor

Hagen

Kupperman

Goretta

et al. 1996

Supercond. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…On the other hand, a recent comparison between the transport J c (µ 0 H ) behaviour and magnetic J c (µ 0 H ) behaviour of the Tl-1223/Ag tape [30] showed that, at high fields (µ 0 H > 100 mT), a few strongly linked current paths do survive and the residual transport current may be limited by intragranular dissipation, as suggested by previous work [31]. Furthermore, measurements of the anisotropy of J c (transport) for this phase suggest that, although the bulk of the tape core is untextured, the strongly linked current paths that survive to high fields are significantly textured [30].…”

Section: Discussionsupporting

confidence: 58%

Well-defined grain boundary weak-links in silver-sheathed ( tape conductors

Everett

Dhallé

Johnston

et al. 1996

Supercond. Sci. Technol.

View full text Add to dashboard Cite

The key factors that make the thallium-based 1223 phase conductors attractive candidates for high-field applications at 77 K are a high transition temperature (about 115 K) and an irreversibility line comparable to that of YBa 2 Cu 3 O 7 . However, a third important factor is the grain boundary behaviour. We have performed detailed current-voltage (I -V ) studies of a silver-sheathed (Tl 0.78 Bi 0.22 )(Sr 0.8 Ba 0.2 ) 2 Ca 2 Cu 3 O x (Tl-1223/Ag) tape. Although the tape has a fairly high self-field critical current density J c at 77 K (about 5 × 10 3 A cm −2 ), the I -V characteristics display the 'weak-link' signatures well known for YBa 2 Cu 3 O 7 : linear dissipation above a sharply defined critical current, a pronounced decrease of J c in a magnetic field H and hysteresis with respect to field cycling. Broader implications for the superconductive behaviour of HTS grain boundaries are discussed.

show abstract

“…Although some studies have been carried out on Tl HTSC tapes, using the widely employed powder-in-tube method [13][14][15], very few studies seem to have been published on Tl HTSC tapes prepared by use of the doctorblade tape-casting technique. Among the various methods employed for tape casting, the doctor-blade tape-casting technique is considered to be one of the attractive routes for producing very long homogeneous superconducting tapes suitable for many practical applications.…”

Section: Introductionmentioning

confidence: 99%

The synthesis and characterization of tapes and the Ag-induced effect on their microstructure

Asthana

Verma

Srivastava

1997

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

The present study is based on improving the intergranular connectivity of Tl HTSC tapes by passivation of grain boundaries through the addition of silver. HTSC tapes to which silver had been added were fabricated by the diffusion of Tl vapour in the precursor tape to which silver had been added. The tapes were cast by using a doctor-blade tape-casting machine. These tapes having Tl:2223 as the majority phase were found to possess in the range 107 - 113 K. The critical current density of the Tl HTSC tapes was found to scale with the silver content and optimum (20 K) and (77 K) were obtained for HTSC tapes. SEM of pure (without silver) and Ag-admixed Tl:2223 tapes revealed that, as the silver content increased, the grain size and intergranular connectivity increased. With an optimum concentration of Ag (y = 0.40), a well-oriented platelet-like grain structure became stabilized, leading to an improvement in . The most curious microstructural feature, observed for the first time in the present study, was the occurrence of sequential layer growth features resembling spiral characteristics. The influence of these microstructural features on the superconducting properties, in particular the transport critical current density, is described and discussed.

show abstract

Granularity, microstructure, and flux creep in TlBa2Ca2Cu3O9+δ superconducting powder and silver-sheated tapes

Cited by 23 publications

References 36 publications

Liquid phase sintering and microstructure development of Ag-clad Tl-1223 superconductor

Liquid phase sintering and microstructure development of Ag-clad Tl-1223 superconductor

Well-defined grain boundary weak-links in silver-sheathed ( tape conductors

The synthesis and characterization of tapes and the Ag-induced effect on their microstructure

Contact Info

Product

Resources

About