Ferrite Magnet The Magnet Is Hard And Brittle

Ferrite magnets are a permanent magnet made of SrO or BaO and Fe2O3 as raw materials. Early developed by the gifted magnetic company, compared with other permanent magnet, ferrite magnets hard and brittle, low magnetic energy. But it is not easy to demagnetize the corrosion is not easy, the production process is simple and inexpensive, therefore, in the entire magnet industry, the highest output of ferrite magnets and is widely used in industrial production.

Ferrite magnets are sintered permanent magnet materials, composed of barium and strontium iron body, this kind of magnetic material in addition to a strong anti-demagnetization performance, there are advantages of low cost. The ferrite magnets are rigid and brittle and require special machining processes. The magnetism of the opposite magnets is magnetized in the direction taken in the direction of its manufacturing, and its homogeneous magnets can be magnetized in any direction without being oriented, although a slightly stronger magnetic induction is found on the face where the compression surface is often the smallest. The magnetic energy product ranges from 1.1MGOe to 4.0MGOe. Due to the low cost, ferrite magnets have a wide range of applications, from motors, speakers to toys, handicrafts, and thus is currently the most widely used permanent magnet materials.

Using powder metallurgy method of production, residual magnetization is low, the magnetic permeability is small. Coercive force is strong, strong anti-magnetic ability, especially suitable for dynamic working conditions of the magnetic circuit structure. The material is hard and brittle and can be used for cutting tools with emery tools. The main raw material is oxide, it is not easy to corrosion. Operating temperature: -40 ° C to + 200 ° C.

Ferrite magnets are divided into the opposite sex (anisotropy) and the same sex (isotropic). The isotropic sintered ferrite permanent magnet material has a weak magnetic properties but can be magnetized in different directions of the magnet. The anisotropic sintered ferrite permanent magnetic material has strong magnetic properties but can only follow the magnet Fixed magnetization direction.

In the actual production of ferrite magnets, the chemical composition of good raw materials, and sometimes may not be able to obtain a good performance and microstructure of ferrite magnets, the reason is the physical properties of the impact. The physical properties of the listed iron oxides include the average particle size APS, the specific surface area SSA, and the bulk density BD. As the manganese zinc ferrite magnets in the formula accounted for about 70% of iron oxide, so its APS value of ferrite magnets powder APS value has a great impact. In general, iron oxide APS value is small, ferrite magnets powder APS value is also small, is conducive to speed up the chemical reaction speed. However, taking into account the fine powder particles are not conducive to post-press suppression and sintering easy to crystallize the situation, APS value should not be too small. Obviously, when the iron oxide APS value is too large, in the calcination, because the larger particle size, only the spinel phase diffusion reaction, can not be further grain growth process. This inevitably leads to an increase in the activation required during sintering, which is detrimental to the solid phase reaction.