Permanent Magnet Formation

Steel or other materials can become permanent magnets, because they are in the best state when they are properly processed and processed, and the coercive force is the largest. Iron has little uniformity in crystal structure and internal stress, so its coercivity is very small, making magnetization or demagnetization do not require strong magnetic field, so it can not become permanent magnets. Materials that are usually easy to magnetize and degaussing are called "soft" magnetic materials. "Soft" magnetic materials cannot be permanent magnets, and iron belongs to this kind of material.