Following the steps of Xiaobian, I summarized 5 common NFC ferrite tablets on the market today, hoping to give them to friends in need.
First of all, let's learn about NFC ferrite sheet: 13.56MHz antenna ferrite sheet / film, a kind of high temperature sintered ferrite material
。 In the NFC (near field communication) payment mobile phone and other handheld devices, the main function of the electronic tag is to reduce the
At the same time, the ferrite film itself is a kind of ferrite material sintered at high temperature
Degree, effectively increase the sensing distance.
NFC ferrite sheet
Five common NFC ferrite tablets on the market:
1. Soft ferrite
Soft ferrite has the most varieties and is widely used. According to different uses, there are various ferrites with similar composition and properties, such as
In the ultra-high frequency range, we can choose the hexagonal ferrite of magnetoplumbite type, and in the audio frequency, medium frequency and high frequency range, we can use spinel type Mn Zn
Ferrite, Ni Zn ferrite, Li Zn ferrite, etc.
Soft ferrite molding, general color; dry pressing, extrusion, grouting or hot die casting and isostatic pressing, hot pressing and explosion methods.
In order to reduce the sintering shrinkage of the products, make the reaction sufficient, and improve the intrinsic properties of ferrite, it is generally necessary to carry out pre firing first, and some of them should be pre fired
Some of them are pre fired at high temperature or even twice.
2. Hard ferrite
Hard ferrite can be called permanent magnetic materials, mainly including: Ba Ferrite, Sr ferrite, Pb ferrite and so on
There are spinel type CO ferrite. The sintering density of ferrite is related to the residual magnetic induction strength,
The larger the residual magnetic induction is. Although increasing the sintering temperature can increase the density of the magnet, it will lead to the growth of the magnetic grains
The intensity of magnetic induction is unfavorable.
3. Gyromagnetic ferrite
Gyromagnetic ferrite is mainly used to make all kinds of microwave components, so it is also called microwave ferrite. At present, the main
There are spinel type and garnet type ferrite. The magnetoplumbite type gyromagnetite can be used in very high frequency range
Sr and Pb ferrites are made of a part of Fe.
4. Moment ferrite
Generally speaking, spinel ferrite with high density, uniform grain size and large crystalline anisotropy can be made into moment ferrite
The volume has a good rectangular hysteresis loop, but it needs a large current when it is over magnetized, which is disadvantageous to the work of the core.
5. Pressure ferrite
The density of pressure ferrite is directly related to its piezomagnetic properties. In production
In the process, we can increase the molding pressure, increase the sintering temperature, introduce additives and high temperature pre sintering methods to improve the ferrite
Absorbing material: www.goodsmaterial.com