Shielding a Magnetic Field with Neodymium Magnets

by Ryan Brown Custom Of Permanent Magnets

Samarium-cobalt and neodymium magnets are the two most popular rare earth magnets. The more affordable and strongest kind is considered to be Neodymium or ARC Neodymium Magnet. It's used for hard drives, electric motors for cordless tools, jewellery clasps, and others.

Meanwhile, samarium-cobalt is commonly used by industrial manufacturers and is considered to be on the pricey side.

Having a magnetic force that can act on another magnet or traveling electric current or charged particle, a magnet traveling electric current or charged particle have a magnet around them. When you drop iron filings around the magnet, this field is quite evident and forming along the lines of this field, you will see a certain pattern.

In a practical application, when a magnetic field is used as from this field, there are instances when an object has to be protected and by a procedure called shielding, this is done. Altering the lines of magnet, a shielding material is used. The field lines in fact conduct along a path of least resistance that it creates.

Therefore in its literal meaning, shielding is not to be taken as lines of the magnet are not stopped or blocked, and their path is only altered. For field lines to travel the shielding material offers a low energy pathway and as compared to air, it is better conductor.

Shielding is not a tough process; however to get the best results, one has to consider several factors. Firstly, as lines of the Bar Neodymium Magnet will be resistant to make sharp turns the shape of the shield should not have sharp corners. Therefore, shields in spherical and cylindrical shapes are most effective.

The size of the shield is the next aspect to consider. To more lines of the magnet, a large shield will be exposed obviously; however to travel through the shield, these lines will not be induced. Usually, for shielding the space that is beyond two to three feet from the magnetic source, a shield measuring six foot square would be sufficient in a practical home setting.

With layering the material, the efficacy of the shield is increased and maximising its thickness. Lastly, a difference will be made by proper alignment of the surface of shield. The magnetic field's orientation is affected by the way the shield is placed as it encounters the surface of the shield.

To be as parallel as possible, the best placement is aligning shield surface so that maximum of the edge area is exposed to the field.

According to the strength of the magnetic field of ARC Neodymium Magnet, the shielding material will also vary. Materials like Magnet Shield, Paper Shield and Grion are quite effective for strong fields and they offer good high saturation and permeability.

Good shielding materials are Met Glass, Magnetic Shielding Foils, and Mag-Stop Plates in applications having moderate to weak fields. Finement and CobalTex are effective in high frequency applications.

Before you start your project on shielding the field, determine the level of attenuation required and measure the magnetic field, you must consider all these factors.