A magnet, a moving charged particle, or an electric current have a magnet around them, which is an area with magnetic force that can act on another magnet, a moving charged particle, or an electric current. This field is quite obvious when you throw iron filings around a magnet, and you see a certain pattern that forms along the lines of this field.
When a magnetic field is used in a practical application, there are cases where an object must be protected from this field, and this is done using a procedure called shielding. A shielding material is used that changes the lines of the magnet. In fact, the material “draws” the lines of the field along the path of least resistance, which it creates. Therefore, shielding should not be taken in a literal sense, since the lines of the magnet are not blocked or stopped, but only their path changes. Protective material offers a low-energy path for the movement of field lines and a better conductor than air.
Escaping is not a complicated procedure; however, several factors need to be considered for best results. First, the shape of the screen should not have sharp corners, since the lines of the magnet will be resistant to sharp turns. Therefore, screens in cylindrical and spherical forms are most effective.
The next aspect to consider is the size of the shield. A large shield will clearly be exposed to more magnets; however, these lines will not be forced to pass through the shield. Usually in a practical home environment for screening a space two to three feet away from a magnetic source, a screen of 6 feet is enough.
The effectiveness of the shield is increased by using a layer of material and increasing its thickness. Finally, the correct alignment of the screen surface will also matter. The way the shield is placed affects the orientation of the magnetic field when it collides with the surface of the screen. Better placement aligns the screen surface in parallel or as parallel as possible, so that the maximum of the edge region is exposed to the field.
The protective material will also differ depending on the strength of the magnetic field. For strong fields, materials such as the Grion, PaperShield and MagnetShield are quite effective and provide good permeability and high saturation. In applications with moderately weak fields, Mag-Stop plates, magnetic shielding films and MetGlass are good shielding materials. In high frequency applications, CobalTex and Finement are effective.
Consider all factors, measure the magnetic field and determine the required attenuation level before starting a field shielding project.
