How to choose the magnetic core?

Classification of magnetic materials

Magnetic materials are divided into two types: soft magnetic materials and hard magnetic materials. Magnetic materials that are easily demagnetized after magnetization are called soft magnetic materials, and their coercive force is very small. Hard magnetic materials (such as magnetic steel and permanent magnetic alloys) are not easy to demagnetize.

Soft ferrite cores are an important category of magnetic materials. They are widely used, such as magnetic rods in radios, magnetic cores in tape recorders and televisions, magnetic rings of deflection coils, magnetic heads of video recorders, and high-frequency transformers in switching power supplies.

Soft ferrite cores come in many varieties and shapes, and can be roughly classified as follows:

(1) Classification by shape: mainly threaded cores, ring cores (referred to as magnetic rings), tubular cores, pot cores (i.e. magnetic pots), E-shaped, sun-shaped, U-shaped, T-shaped, I-shaped, and Wang-shaped cores. In addition, there are single-hole, double-hole, and multi-hole cores.

(2) Classification by working frequency: there are low frequency, medium frequency, high frequency and very high frequency cores.

(3) Classification by material: the material grades are as follows: MXO-manganese zinc ferrite; NXO-nickel zinc ferrite; NQ-nickel lead ferrite; NGO-nickel zinc high frequency ferrite; GTO-very high frequency ferrite.