Explanation
Iron is a composite oxide of iron and one or more other appropriate metal elements. Its magnetism belongs to ferrimagnetism, which originates from the super exchange between magnetic metal ions separated by oxygen ions. It makes the magnetic moment of metal ions at different lattice positions reverse. When the magnetic moment of opposite arrangements are not equal, it shows strong magnetism. Therefore, the basic characteristics of ferrite are closely related to crystal structure, chemical bond and ion cloud distribution. There are three types of crystal structure of ferrite: spinel type, magnetite type and garnet type. Among them, spinel type and magnetite lead type of soft magnetic materials are mainly used as permanent magnet material, while garnet type is largely used as gyromagnetic material.
Classification
Information materials -> Materials for electronic components -> Magnetic materials