Permanent Magnet is a magnet that can maintain its magnetism for a long time.
Formation of Permanent Magnet
Steel or other materials can become Permanent Magnet
because they are properly processed and processed, the internal inhomogeneity is in the best state, and the coercivity is the greatest. The inhomogeneity of the crystal structure and internal stress of iron is very small, and the coercive force is naturally very small so that it does not need a strong magnetic field to magnetize or demagnetize, so it can not become Permanent Magnet.
Materials that are easy to magnetize and demagnetize are usually called "soft" magnetic materials. "Soft" magnetic materials can not be used as Permanent Magnet, iron belongs to this material.
Application of Permanent Magnet
Permanent Magnet has a wide range of applications, including televisions, speakers, loudspeakers, radios, leather buckles, data wire magnetic rings, computer hard drives, mobile phone shakers and so on. Permanent Magnet, such as loudspeakers, uses the principle that the coil moves in a magnetic field to produce sound. Permanent Magnet on the horn uses the magnetic field generated by the current to interact with it when the current in the coil changes, which changes the relative position of the coil and the magnet, drives the paper basin on the horn to vibrate, drives the air and propagates the vibration, so that the human ear can hear the sound. In a word, Permanent Magnet is ubiquitous in people's life. It facilitates our production and life.