Physics – Condensed Matter – Superconductivity
Scientific paper
2008-05-09
Physics
Condensed Matter
Superconductivity
Scientific paper
10.1088/0953-2048/21/10/103001
The magnetic and transport properties of magnesium diboride films represent performance goals yet to be attained by powder-processed bulk samples and conductors. Such performance limits are still out of the reach of even the best magnesium diboride magnet wire. In discussing the present status and prospects for improving the performance of powder-based wire we focus attention on (1) the intrinsic (intragrain) superconducting properties of magnesium diboride, Hc2 and flux pinning, (2) factors that control the efficiency with which current is transported from grain-to-grain in the conductor, an extrinsic (intergrain) property. With regard to Item-(1), the role of dopants in Hc2 enhancement is discussed and examples presented. On the other hand their roles in increasing Jc, both via Hc2 enhancement as well as direct fluxoid/pining-center interaction, are discussed and a comprehensive survey of Hc2 dopants and flux-pinning additives is presented. Current transport through the powder-processed wire (an extrinsic property) is partially blocked by the inherent granularity of the material itself and the chemical or other properties of the intergrain surfaces. These and other such results indicate that in many cases less than 15% of the conductor's cross sectional area is able to carry transport current. It is pointed out that densification in association with the elimination of grain-boundary blocking phases would yield five-to ten-fold increases in Jc in relevant regimes, enabling the performance of magnesium diboride in selected applications to compete with that of Nb-Sn.
Bhatia Manjit
Bohnenstiehl S. D.
Collings E. W.
Sumption M. D.
Susner M. A.
No associations
LandOfFree
Prospects for Improving the Intrinsic and Extrinsic Properties of Magnesium Diboride Superconducting Strands does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Prospects for Improving the Intrinsic and Extrinsic Properties of Magnesium Diboride Superconducting Strands, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Prospects for Improving the Intrinsic and Extrinsic Properties of Magnesium Diboride Superconducting Strands will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-332699