The magnetization of a spherical magnet is an important process that gives it magnetism. It is mainly achieved through the following common methods, and each method is based on a specific physical principle.
1. Current magnetization method
This is a magnetization method that uses the principle of electromagnetic induction. When a spherical magnet is placed in a energized solenoid, the current in the solenoid will generate a magnetic field. According to the Ampere loop theorem, the direction of the magnetic field generated by the current around the solenoid is determined by the right-hand screw rule. For a spherical magnet, this external magnetic field will cause the originally chaotic magnetic domains inside the magnet to be oriented.
A magnetic domain is a small area with spontaneous magnetization properties inside a magnetic material. In the unmagnetized state, the magnetization directions of each magnetic domain are randomly distributed, and the whole is not magnetic to the outside. When in the magnetic field of a energized solenoid, the magnetic domains gradually rotate under the action of the magnetic field force, so that their magnetization directions tend to be consistent with the direction of the external magnetic field. As the magnetic domains are continuously oriented, the magnetism of the spherical magnet gradually increases. By controlling the magnitude and direction of the current, the intensity of the magnetization and the direction of the magnetic poles can be adjusted. Generally speaking, the larger the current, the stronger the magnetic field, the more obvious the directional effect on the magnetic domain, and the stronger the magnetism of the spherical magnet.
2. Permanent magnet magnetization method
The spherical magnet can also be magnetized using a magnetized permanent magnet. The spherical magnet is closely contacted with a strong permanent magnet so that the magnetic field of the permanent magnet acts on the spherical magnet. At this time, the magnetic domains inside the spherical magnet will also be affected by the magnetic field of the permanent magnet and rearranged.
For example, if an N pole is close to one end of the spherical magnet, the end of the spherical magnet close to the N pole of the permanent magnet will gradually form an S pole, and the other end will form an N pole. The effect of this magnetization method depends on the magnetic strength of the permanent magnet and the contact method between the two. If you want to get a stronger magnetization effect, you can combine multiple permanent magnets to form a stronger magnetic field to magnetize the spherical magnet. However, the magnetization intensity of this method is relatively limited, because the magnetic field strength of the permanent magnet itself is fixed, unlike the current magnetization method, which can easily change the magnetic field strength by adjusting the current.
3. Pulse magnetization method
Pulse magnetization is an efficient magnetization method. By instantly releasing high-energy pulse current, a very strong magnetic field is generated in a very short time. When the spherical magnet is in this pulse magnetic field, its internal magnetic domains will be quickly forced to align. The advantage of pulse magnetization is that it can achieve high-intensity magnetization in a short time, which is especially suitable for spherical magnets with high magnetic requirements. At the same time, precise control of pulse parameters (such as pulse width and peak current) can accurately adjust the magnetization degree and magnetic pole direction of the spherical magnet.
