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Significantly enhanced critical current densities in MgB2 tapes made by a scaleable, nano-carbon addition route

Yanwei Ma·Xianping Zhang·G. Nishijima·K. Watanabe·Xuedong Bai
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Abstract

Nanocarbon-doped Fe-sheathed MgB2 tapes with different doping levels were prepared by the in situ powder-in-tube method. Compared to the undoped tapes, Jc for all the C-doped samples was enhanced by more than an order of magnitude in magnetic fields above 9 T. At 4.2 K, the transport Jc for the 5 at% doped tapes reached 1.85x104 A/cm2 at 10 T and 2.8x103 A/cm2 at 14 T, respectively. Moreover, the critical temperature for the doped tapes decreased slightly. Transmission electron microscopy showed a number of intra-granular dislocations and the dispersed nanoparticles embedded within MgB2 grains induced by the C doping. The mechanism for the enhancement of flux pinning is also discussed. These results indicate that powder-in-tube-processed MgB2 tape is very promising for high-field applications.

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Yanwei Ma, Xianping Zhang, G. Nishijima, K. Watanabe, Xuedong Bai. 2006-01-11. Significantly enhanced critical current densities in MgB2 tapes made by a scaleable, nano-carbon addition route. https://doi.org/10.1063/1.2173635

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