Magnetic shielding properties of NbTi/Nb/Cu multilayer composite tubes

Nippon Steel Corp., Kawasaki
IEEE Transactions on Applied Superconductivity (Impact Factor: 1.24). 04/1993; 3(1):177 - 180. DOI: 10.1109/77.233699
Source: IEEE Xplore


Magnetic shielding properties have been investigated using Hall
plates at 4.2 K in a parallel magnetic field up to 4 T for
superconducting cylinders with and without a bottom, which are
multilayer composites consisting of NbTi, Nb, and Cu. These composite
cylinders were fabricated by deep drawing a multilayer composite sheet
made by cladding and rolling. It was found that a sample of five
concentrically stacked cup-shaped cylinders, with a thickness of 1 mm,
an inside diameter of 20-40 mm, and a length of 45 mm, can reduce the
external magnetic field of 3 T to less than 10 G

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    • "But the shell is made of pure iron in order to have satisfying magnetic performance at high field. For requirement 4, a cylindrical superconducting magnetic shield ensures efficiency up to 100 % at 4.2 K, for background fields up to few T. In particular, a NbTi/Nb/Cu multilayer composite [20] and a bulk of MgB 2 [21] are considered. In this way, a superconducting shield of thickness 6 mm is capable of screening up to 1 T [22] leaving the design of the iron shell concerned only with the off-centering issue. "
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