Shielding of static magnetic fields by textiles

Low-frequency and static magnetic fields occur, e.g., in mains transformers, motors, oscilloscopes, strong laboratory magnets etc. They can be shielded only by materials of high permeability. For weak magnetic fields, μ-metal or Metglas have very high permeabilities leading to large shielding factors. However, both materials are not suited for larger fields, since the field-dependent permeability decreases significantly for magnetic fields of about 1 Oersted (Oe) or higher. In our experiments, we integrated metallic fine yarns fine and yarns from different magnetic materials into warp-knitted fabrics. These fabrics were formed into cylinders of defined diameter. The shielding factor was measured in the field range of ± 100 Oe. Shielding ratios were found to be much lower than values of a solid steel bar; however, these experiments point out that shielding of static magnetic fields with magnetic textiles is possible in principle.