Ferrite Formula and Types of Ferrites
Ferrite is usually ceramic, standardized material and it has ferrimagnetic properties. We can say in other words that, Ferrite is a ceramic material made by reacting or relating metal oxides into a magnetic material. Ferrites are insulators and having ferrimagnetic property i.e. they can be easily magnetized.
More details on Ferrite you can find in my previous blog;
The ferrite formula is commonly stated as MeFe2O4.
Where “Me” signifies a divalent metal ion.
e.g. Fe²⁺, Ni²⁺, Mn²⁺, Mg²⁺, Zn²⁺, Cu²⁺, Co²⁺, etc.
Types of Ferrites
On the basis of their resistance to being demagnetized, Ferrites can be divided into two types of ferrites; Soft and Hard Ferrites.
1) Hard Ferrite Core
Hard Ferrite Cores have high coercivity i.e. it can withstand an external applied magnetic field without becoming demagnetized.
The coercivity for ferromagnetic material is the strength of the externally applied magnetic field needed to decrease the magnetization of that material to zero, once the magnetization of that material has been bring to saturation.
Hard Ferrite Applications: Hard Ferrite Cores are used to make permanent magnets which can be used in speakers and motors.
2) Soft Ferrite Core
Soft Ferrite Cores have low coercivity i.e. it can’t withstand an external applied magnetic field and easily demagnetized.
They simply change their magnetization, and they act as conductors of magnetic fields.
Soft Ferrite Applications: Soft Ferrite Cores are used to make ferrite cores for high frequency applications like Inductors and Transformers.
Soft Ferrite Materials are characterised by Spinel or cubic crystal structure. Generally at high frequencies, soft ferrites have many advantages as compare to conventional metallic type materials.
Different core geometries optimized for specific applications can be achieved by shaping ferrites.