Ferrite is a permanent magnet material made of iron oxide and alkaline earth metal oxides (such as SrO or BaO), also known as hard ferrite. They are made by ceramic processes (including pre-firing, crushing, grinding, pressing, sintering and grinding) and have a wide hysteresis loop, high coercivity and high remanence, capable of maintaining constant magnetism once magnetized. The crystal structure and chemical composition of ferrite are one of its basic characteristics. In the ferrite crystal structure, oxygen ions are the densest, and they form a tightly packed three-dimensional structure. Iron and transition metal ions are inserted between these oxygen ions to form the crystal structure. Iron ions can be in two oxidation states, +2 and +3, while transition metal ions can be elements such as iron, zinc, nickel, and manganese.
Depending on the process, ferrite permanent magnets can be divided into two types: sintered ferrite and bonded ferrite. Sintered ferrite can be divided into dry pressing and wet pressing, bonded ferrite can be divided into extrusion molding, injection molding and rolling molding. Ferrite permanent magnets are isotropic and anisotropic. According to different forming processes, anisotropic ferrites can be divided into dry pressing and wet pressing.
Main properties: magnetic, electrical conductivity, thermal stability
Ferrite is a kind of functional ceramic material with important application value and has many main properties. One of the most important properties is magnetism. Ferrite materials contain a large number of iron and oxygen ions, and form strong magnetism through magnetic interaction. This kind of magnetism has the characteristics of high temperature stability and high saturation magnetic induction strength, which makes ferrite widely used in the manufacture of electronic components, electromagnetic devices and motors.
The advantages of ferrite are rich raw material sources, high cost performance, excellent chemical stability, no surface treatment, high temperature resistance. Since the advent of NdFeb products, ferrite magnetic materials have also developed rapidly, NdFeb products and ferrite products will be a long-term coexistence and sustainable development pattern.
In addition to magnetism, ferrite materials also have good electrical conductivity and are a typical semiconductor material. The electrical conductivity of ferrite can be regulated by doping, thus achieving fine control of the electrical properties of the material. In addition, ferrite also has good thermal stability. The coefficient of thermal expansion of ferrite is similar to that of metal matrix, so it has excellent mechanical properties and thermal stability in high temperature environment, and is a kind of material with good heat resistance and high temperature resistance.
Guangdong South Magnetic Technology Co., Ltd. has more than 20 years of magnetic product production experience, can produce injection molded ferrite magnetic ring androtor, welcome to consult.
