You need to know about these things of nanocrystalline cores
Date：2021-09-25 15:29
Characteristics of nanocrystalline cores
On the one hand, it can isolate eddy current, and the data is suitable for higher frequencies; On the other hand, due to the gap effect between particles, the data has low permeability and constant permeability; Because the particle size is small, there is basically no skin phenomenon, and the change of permeability with frequency is relatively stable; Moreover, the powder core can be prepared into special-shaped parts of various shapes for different fields; Finally, the damaged strip in industry can be crushed into magnetic powder, and then made into magnetic powder core, which can reduce the loss and improve the use value of data. The magnetoelectric properties of magnetic particle core mainly depend on the permeability of powder material, size and shape of powder, filling coefficient, content of insulating medium, forming pressure and heat treatment process. The soft magnetic particle core will still be high along the high BS in the future μ、 High Tc, low PC, magnetic powder core is a soft magnetic material made of ferromagnetic powder and insulating medium. Because the ferromagnetic particles are very small (0.55 for high frequency) μ M is separated by non-magnetic electrical insulating film material. Low HC and high frequency, miniaturization and thinness to meet the trend of increasingly thin film, miniaturization and even integration of magnetic components.
Characteristics and application of nanocrystalline magnetic core
High permeability, nanocrystalline Fe73.5Cu1Nb3Si13.5B9 alloy has high saturation magnetic induction. The material becomes brittle after heat treatment and is easy to be processed into alloy powder. Compared with the nanocrystalline magnetic core wound with strip, the magnetic permeability of the nanocrystalline magnetic core is still very low and the soft magnetic properties are unstable. At present, the urgent problems to be solved are as follows: 1. Effectively control the growth of nanocrystals during heat treatment; 2. Molding of magnetic particle core; 3 Effect of heat treatment specification on soft magnetic properties of magnetic particle core.
Application field of nano magnetic core
Noise is the main circuit interference source in many power electronic devices. Various filter elements must be used to reduce noise. As the main component of differential mode inductance, magnetic particle core plays a key role in the filter. In order to obtain better filtering effect, the magnetic particle core material is required to have the following performance characteristics: high saturated magnetic induction, wide constant magnetic conductivity, good frequency characteristics, good AC / DC superposition characteristics and low loss characteristics. According to the above requirements, soft magnetic materials for inductance such as iron powder core, notched amorphous alloy core and iron nickel aluminum powder core (MPP powder core) have been developed successively. These materials have played their respective advantages and roles under different application conditions. At present, up powder core occupies the main share in the high-end market. However, due to the complex manufacturing process of M, that is, powder core and the noble price of raw materials, the price of powder core remains high and the scope of application is restricted to a certain extent. In recent years, iron-based nanocrystalline soft magnetic powder core has attracted much attention because of its low price, simple preparation process and excellent performance. Its research is quite active, which is expected to replace the local use of up powder core and be applied in the field of high frequency.