Introduction
Ferrite core is mainly composed of iron (Fe), manganese (Mn), and zinc (Zn) three kinds of metal elements, commonly known as manganese zinc ferrite. The toroidal ferrite core has a high magnetic effect because there is no air gap and the cross-sectional area is the same.
Ferrite magnetic rings have many specifications and sizes, which can be selected according to the material of the magnetic ring, and different coatings can be used to simplify the winding and increase the breakdown voltage.
Ferrite core is made of dense and homogeneous ceramic structure non-metallic magnetic material, has low coercive force, also known as soft ferrite. It consists of oxide or carbonate compounds of iron oxide (Fe2O3) and one or several other metals (such as manganese, zinc, nickel, magnesium). The ferrite raw material is pressed, then sintered at a high temperature of 1300 degrees C, and finally processed into a finished magnetic core that meets the application needs. Compared with other types of magnetic materials, the advantage of ferrite is that the magnetic permeability is very high. And it has the advantages of high resistance and low eddy current loss in a wide frequency range. These material properties make ferrite an ideal material for manufacturing high-frequency transformers, broadband transformers, adjustable inductors and other high-frequency circuits from 10kHz to 50MHz.
2 use
Winding a coil on a ferrite core can make an inductor or a transformer, and they are widely used in instruments, communication equipment, and household appliances. Ferrite cores have many grades of materials and many geometric shapes, including cylindrical, I-shaped, cap-shaped, single-hole, double-hole, four-hole, U-shaped, pot-shaped, E-shaped, EI-shaped, EC-shaped, RM shape, PQ shape, EP shape, see the picture. Each shape of the magnetic core is a series for users to choose. Ferrite cores have a wide range of choices. Different materials and shapes can be selected according to different magnetic parameters. Due to the low magnetic loss at high frequencies, they are widely used in switched mode power supplies (SMPS), radio frequency (RF) transformers And inductors. Ferrite cores of various shapes and sizes are used in inductors, pulse transformers, high-frequency transformers, and noise filters in high-frequency power supplies and high-quality communication markets. The biggest characteristics of ferrite are high permeability, good temperature characteristics, and low attenuation rate.
3 specific data
An inductor made by winding a coil on a ferrite core has a larger inductance than an air-core coil of the same volume, and its Q value (quality factor) is also high. For example, Gu-22×13 pot-shaped magnetic core, when it is used to make a 4mH inductor, only need to wind 43 turns of the coil. If you do not use the pot-shaped magnetic core and change to an air-core coil, you need to wind 600 turns to get 4mH inductance Device. This shows that the use of magnetic cores can greatly reduce the size of inductors or transformers.