Hard Ferrite magnets (ceramic magnets), composed of Barium or Strontium, are sintered magnet material and manufactured by pressing, sintering, or injection molding. These magnets can be both anisotropic and isotropic.
This class of magnets has good resistance to demagnetization and especially popular advantage of low cost. However, They are very hard, brittle and should be machined in an unmagnetized state with specialized machining techniques. This class of magnets have lower energy characteristics compared to other magnetic materials.
The corrosion resistance of Ferrite is considered excellent , and no surface treatments are required. However, Ferrite magnets may have a thin film of fine magnet powder on the surface and for clean, non-contaminated applications, some form of coating may be required.
Due to their low cost, Ferrite magnets enjoy a very wide range of applications, from motors and loudspeakers to toys and crafts, and are the most widely used magnet material today.