Magnetic Shielding by Superposition of Hybrid Ferromagnetic Cylinder over a YBCO Thick-Film Cylinder.

Abstract

In magnetic shielding using high critical temperature (high-Tc) superconducting thick-films, it is, in general, difficult to fabricate very high-Jc (critical current density) vessels. The practical difficulty of realizing magnetic shielding using high-Tc superconductors requires to improve the magnetic shielding effect on the high-Tc superconducting vessels. The maximum shielded mag- netic flux density (Bs) is shown to be improved by the superposition of a hybrid ferromagnetic cylinders over a Y-Ba-Cu-O (YBCO) thick-film cylinder; termed the hybrid-type superimposed cylinder. The value of Bs for the hybrid-type superimposed cylinder was obtained to be about 160 times larger than that for the single-YBCO thick-film cylinder.