Some foreign customers have asked whether NdFeB magnet can be transported by air. As we all know, the magnetism of iron-boron magnets is very strong. If taken on an airplane, it may affect electronic equipment, etc., so the NdFeB magnet need to be degaussed. The so-called Demagnetization, in fact, the magnetism of the magnet itself does not disappear, but the magnetic field distribution of the magnet is changed by the magnetic conductive material to weaken the magnetism, that is, magnetic isolation packaging.
Magnetic isolation packaging is usually separated by iron sheets, fixed on six sides in the box, and then packed in pearl cotton bags and cartons, so that it can pass the airline's security inspection.
What is the principle of magnetic isolation?
The principle of magnetic isolation is to shield magnetic fields, which mainly refers to stable magnetic fields or low-frequency magnetic fields. It mainly relies on magnetic field loops. If the box is made of magnetic materials with high permeability, the "magnetic lines" that would otherwise go out of the box will be concentrated. It forms a closure with the box material, thereby greatly reducing the leakage of magnetic field lines outside the box.
What are the commonly used methods for magnetic isolation?
In order to achieve magnetic shielding, the higher the magnetic permeability of the material, the better; for the same material, the thicker the better; for the same material and thickness, the more layers the better. In addition, the NdFeB magnet should be placed in the center of the shielding box to prevent the magnetic field lines on one side from being more concentrated and leaking out more.
Second, the material is magnetized. Magnetic permeable materials are always melted in a magnetic field, but except for hard magnetic materials, once the external field is removed, the magnetism will be eliminated immediately. Therefore, if the NdFeB magnet is made of hard magnetic materials and forms a new independent magnetic field, its effect will be affected. This is why the shielding material can only use soft magnetic materials.
