The effect of used deformation, metal sheath and heat treatment on the I-V curve of ex situ MgB2 composite

被引：6

作者：

Kovác, P ^{[1
]}

Husek, I ^{[1
]}

Melisek, T ^{[1
]}

机构：

[1] Slovak Acad Sci, Inst Elect Engn, Dept Superconduct Phys, Bratislava 84104, Slovakia

来源：

PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2004年 / 401卷 / 1-4期

关键词：

MgB2; composite; V-I characteristics; n-exponents; grain connectivity; pinning;

D O I：

10.1016/j.physc.2003.09.055

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Current-voltage characteristics of MgB2 Composite wires made of ex situ process using Cu, Fe and stainless steel (SS) sheaths have been measured at 4.2 K in the self-field and external magnetic field between 2 and 4 T. It was found that the used mode of deformation (drawing, rotary swaging and two-axial rolling) influences the slope of I-V curve due to affected grain connectivity. Final heat treatment at 950 degreesC/0.5 h improves grain connectivity apparently, which results in I-V characteristic with very high n-exponents. The n-exponents of multi-core wires measured in external field are apparently lower due to a current sharing among the non-uniform filaments surrounded by high resistance matrix. (C) 2003 Elsevier B.V. All rights reserved.

引用

页码：282 / 285

页数：4

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