Study of Magnetic Shielding with Superconducting Materials I

The magnetic shielding with superconducting materials have been studied aiming at the practical application of shieldings. The leakage of the magnetic field should be reduced in order not to induce undesirable effects on the measuring instruments. The shieldings were made by lead, niobium or NbTi wire and the shielding efficieny were compared experimentally in the field direction of parallel to the face of plate or cylinder axis (made by wire). The shield efficiency of the wire was best as expected. Furthermore from the engineering view point, the superconducting wires were decided to use the magnetic shieldings. The several types of network were constructed and the efficiency of shielding were examined with changing the density and structure of meshes. The magnetic field as high as 2T could be reduced to several handreds gauss with the superconducting networks. It was, therefore, concluded that the superconducting networks are applicable to the practical magnet shieldings.