BLACK 40mm RING MAGNETS 40x8mm Ring Magnets Multipurpose Permanent Round Ring Magnet Permanent Magnet

A ferrite is a ceramic material made by mixing and firing large proportions of iron(III) oxide (Fe2O3, rust) blended with small proportions of one or more additional metallic elements, such as barium, manganese, nickel, and zinc. They are both electrically non-conductive, meaning that they are insulators, meaning they can easily be magnetized or attracted to a magnet. Ferrite can be divided into two families based on their resistance to being demagnetized.

Hard ferrite have high coercive force, so are difficult to demagnetize. They are used to make permanent magnets for applications such as refrigerator magnets, loudspeakers, and small electric motors.

Soft ferrite have low coercive, so they easily change their magnetization and act as conductors of magnetic fields. They are used in the electronics industry to make efficient magnetic cores called ferrite cores for high-frequency inductors and transformers, and in various microwave components.

Ferrite compounds are extremely low cost, being made of mostly rusted iron (iron oxide), and have excellent corrosion resistance. They are very stable and difficult to demagnetize, and can be made with both high and low coercive forces.