China Neodymium And Ferrite Magnets Manufacturer & Supplier 
Magnetic field is an invisible force that can affect magnetic materials such as iron, cobalt, and nickel. We usually use magnets to sense the presence of magnetic fields, but did you know that magnetic fields can pass through steel?
Yes, magnetic fields can penetrate steel, but their behavior changes significantly compared to when they are in air (or a vacuum), and they usually do not pass through steel “undamaged” to the other side. More accurately, steel guides, concentrates, and changes the distribution of magnetic fields.
Magnetic field of magnets and steel
Steel is a ferromagnetic material with high magnetic permeability. When we bring a strong magnet close to steel, the steel attracts part of the magnet's magnetic field, causing the magnetic field to become more concentrated in certain areas of the steel. Therefore, steel not only does not “block” the magnetic field, but also changes the distribution and strength of the magnetic field.
However, the propagation of magnetic fields in steel is subject to certain limitations. When the magnetic field strength is too high, the magnetic permeability of steel may reach saturation point, at which point the penetrability of the magnetic field will decrease.
When a magnet approaches steel, the magnetic permeability of the steel enhances the magnetic field on the side of the magnet, causing the adhesive force on the opposite side to weaken. In other words, the magnetic field's penetrating ability through the steel does not generate an adhesive force on the opposite side equal to that of the magnet itself. If the steel is thin, the magnetic field can penetrate and influence the opposite side more effectively. If the steel is thicker or has a higher density, it will to some extent “shield” or weaken the magnetic field's penetrating power, thereby reducing the adhesive force on the other side.
In some applications, such as magnetic field shielding, steel is used to “guide” magnetic fields in order to reduce their impact on other sensitive equipment. For example, shielding layers in electronic devices are often made of steel or similar materials, which utilize their magnetic permeability to weaken interference from external magnetic fields.
Therefore, magnetic fields can penetrate steel, but steel affects the propagation of magnetic fields. It does not completely block the penetration of magnetic fields, but rather changes the distribution and intensity of magnetic fields by “guiding” magnetic field lines.
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