The establishment of a magnetic model

The cause of the saturated ferromagnetic material can be explained by magnetic model. Each domain contains between 1015 and 1016 atoms, and has been magnetized in a sense, the soft magnetic alloy composed of a domain of spin magnetic dipole orientation of children in the same direction, even without applied magnetic field. There are domain wall between different domains, about 100 atoms thick. When the material is PVC, the different domain in different directions with a magnetic moment, random net and does not lead to material magnetization of magnetic field. When the external magnetic field applied to the ferromagnetic materials, magnetic domain wall and the external field, will be at the expense of the field. It would increase magnetic flux. When the magnetic field is weak, the domain movement is reversible, but when reached a certain point, sports will be irreversible. When this happens, the domain will begin to rotate in the same direction. When applied magnetic field into the flux density will not disappear, but up to the level of the Br, referred to as the residual magnetic flux density. Get the magnetic flux density back, Hc applying an external magnetic field, but in the opposite direction, the required strength is called enforced. If the domain are aligned with the external field, the material has reached saturation, and, as shown in, regardless of the amount of magnetic field, applying flux density can be high. Hysteresis losses is when the magnetic domain and applied electric field on the heat loss. Heat is produced by the movement of the friction. In switching applications, such as the transformer and the electric motor has a narrow hysteresis loop, the application of this is due to the small magnetic field will produce larger magnetic flux density, because in each switching cycle, as applied magnetic field in the range of plus or minus delta (d, high-frequency loss will be high. For the same material, high magnetic permeability often leads to higher magnetic core loss. Width of magnetization can also influence core loss. Has a narrow ring material called soft material and has a wide ring of material called a hard material. Hard material used in permanent magnets and soft is used for transformer and inductor.