Title :
Influence of Ball-Milled Low Purity Boron Powder on the Superconductivity of MgB2
Author :
Xu, X. ; Kim, J.H. ; Yeoh, W.K. ; Rindfleisch, M. ; Tomsic, M. ; Santos, Dayse I dos ; Dou, S.X.
Author_Institution :
Wollongong Univ., Wollongong
fDate :
6/1/2007 12:00:00 AM
Abstract :
MgB2 samples were prepared using as-supplied commercial 96% boron with strong crystalline phase and the same 96% boron (B) after ball milling. The effects of the properties of the starting B powder on the superconductivity were evaluated. We observed that samples using ball-milled 96% B, in comparison with the one made from the as-supplied 96% B, were characterized by small grain size, broadened full width at half maximum (FWHM), and enhanced magnetic critical current density (Jc). Jc reached 2 times 103 A cm-2 at 5 K and 8 T. The improved pinning of these samples seems to be caused by enhanced grain boundary pinning at high field.
Keywords :
ball milling; critical current density (superconductivity); grain boundaries; grain size; magnesium compounds; powders; type II superconductors; MgB2; ball milling; grain boundary pinning; grain size; magnetic critical current density; magnetic flux density 8 T; powders; superconductivity; temperature 5 K; Ball milling; Boron; Conducting materials; Critical current density; Crystalline materials; Crystallization; Grain size; Powders; Superconducting materials; Superconductivity; ${rm MgB}_{2}$; Ball milling; crystallinity; magnetic critical current density;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2007.899444
