Improvement of critical current in MgB2/Fe superconducting wires by a ferromagnetic sheath

被引:66
作者
Horvat, J [1 ]
Wang, XL [1 ]
Soltanian, S [1 ]
Dou, SX [1 ]
机构
[1] Univ Wollongong, Inst Superconducting & Elect Mat, Wollongong, NSW 2522, Australia
关键词
D O I
10.1063/1.1447010
中图分类号
O59 [应用物理学];
学科分类号
摘要
Transport critical current (I-c) was measured for Fe-sheathed MgB2 round wires. A critical current density of 5.3x10(4) A/cm(2) was obtained at 32 K. Strong magnetic shielding by the iron sheath was observed, resulting in a decrease in I-c by only 15% in a field of 0.6 T at 32 K. In addition to shielding, interaction between the iron sheath and the superconductor resulted in a constant I-c between 0.2 and 0.6 T. This was well beyond the maximum field for effective shielding of 0.2 T. This effect can be used to substantially improve the field performance of MgB2/Fe wires at fields at least three times higher than the range allowed by mere magnetic shielding by the iron sheath. The dependence of I-c on the angle between field and current showed that the transport current does not flow straight across the wire, but meanders between the grains. (C) 2002 American Institute of Physics.
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收藏
页码:829 / 831
页数:3
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