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arXiv · 0802.3732

Hollow carbon spheres as an efficient dopant for enhancing critical current density of MgB2 based tapes

Zhaoshun Gao·Yanwei Ma·Xianping Zhang·Dongliang Wang·Junhong Wang·K. Watanabe·Boyang Liu
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Abstract

A significant enhancement of Jc and Hirr in MgB2 tapes has been achieved by the in situ powder-in-tube method utilizing hollow carbon spheres (HCS) as dopants. At 4.2 K, the transport Jc for the 850C sintered samples reached 3.1x10^4, and 1.4x10^4 A/cm^2 at 10 and 12 T, respectively, and were better than those of optimal nano-SiC doped tapes. Furthermore, the Hirr for doped sample was raised up to 16.8 T at 10 K due to the carbon substitution effect. The results demonstrate that HCS is one of the most promising dopants besides nano-carbon and SiC for the enhancement of current capacity for MgB2 in high fields.

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Zhaoshun Gao, Yanwei Ma, Xianping Zhang, Dongliang Wang, Junhong Wang, K. Watanabe, Boyang Liu. 2008-08-30. Hollow carbon spheres as an efficient dopant for enhancing critical current density of MgB2 based tapes. https://doi.org/10.1088/0953-2048%2F21%2F10%2F105020

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