Ceramic magnets, which are called Ferrit magnets, divide into two categories; hard ferrits and soft ferrits, in accordance with their permanent magnetic inductions and their structures.
The ferrits, also called hexagonal-structured ceramic magnets formed by barium strontium or lead oxids with iron oxids are in this group. (BaO6Fe2O31SrO6Fe2O3 (Strontium Hegzaferrit) etc.)
They are the most used magnets in practice for their good thermal stability, high temperatures of Curie and are very cheap compared to other magnets.
The most important disadvantage is that their permanent induction and energy are low. Hard ferrits are used especially in servo motors where the problem of volume and weight is not involved; in magnetic devices such as loudspeakers; in the automotive industry; in electric motor rotator; in iron ore enrichment seperators; in making of pots; in making of magnetic bars.
PHYSICAL FEATURES DISTRIBUTION TABLE OF HARD FERRITES
1 T(Tesla) = 103 mT(MiniTesla) = 10 kGs (KiloGauss) = 104G(Gauss), 1 kOe = 79.6 kA/m, 1 MGOe=7.96kJ/m³
*Tw: Max.working Temp.: Maksimum çalışma sıcaklığı; *Tc: Curie Temp.: Küri Sıcaklığı;
*µr: Relative Permeability: Bağıl Geçirgenlik Katsayısı