High critical current density of MgB2 bulk superconductor doped with Ti and sintered at ambient pressure

Citation
Y. Zhao et al., High critical current density of MgB2 bulk superconductor doped with Ti and sintered at ambient pressure, APPL PHYS L, 79(8), 2001, pp. 1154-1156
Citations number
15
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
APPLIED PHYSICS LETTERS
ISSN journal
0003-6951 → ACNP
Volume
79
Issue
8
Year of publication
2001
Pages
1154 - 1156
Database
ISI
SICI code
0003-6951(20010820)79:8<1154:HCCDOM>2.0.ZU;2-J
Abstract
Ti-doped MgB2 superconductors with different doping levels were prepared by solid-state reaction at ambient pressure. The density, diamagnetic signal, and J(c) of the samples change significantly with the doping level, with t he best result achieved at x=0.1. At 5 K, the J(c) reaches 2x10(6) A/cm(2) in the self-field and 5x10(4) A/cm(2) in 5 T. At 20 K, the J(c) is still as high as 1.3x10(6) A/cm(2) in the self-field and 9.4x10(4) A/cm(2) in 2 T. It is observed that partial melting occurs in the Ti-doped samples, resulti ng in an excellent grain connection and extremely high density. In addition , some fine particles (with sizes from 10 to 100 nm) of the second phases i nduced by Ti doping are distributed in the MgB2 matrix, and this may play a n important role in flux pinning enhancement. (C) 2001 American Institute o f Physics.