Industrial Permanent Ferrite Ring Magnets
The size, shape and style of the ferrite ring can be customized. Interested users are welcome to call and contact us. In today’s society, mobile phones are a product that everyone has. In fact, there are many digital products that have ferrite magnetic rings. It is a commonly used anti-jamming component in electronic circuits. It is very good for high-frequency noise. The inhibition effect is generally made of ferrite material (Mn-Zn). The magnetic ring has different impedance characteristics at different frequencies. Generally, the impedance is small at low frequencies. When the signal frequency increases, the impedance of the magnetic ring increases sharply. We all know that the higher the signal frequency, the easier it is to radiate out (it is also necessary to buy a high-quality computer case to reduce electromagnetic leakage), and the general signal lines do not have a shielding layer, so these signal lines become good antennas , receive various messy high-frequency signals in the surrounding environment, and these signals are superimposed on the originally transmitted signals, and even change the original transmitted useful information.
High-Quality Ceramic Ferrite Industrial Magnets
Permanent ferrite magnets are also known as ceramic magnets. The first development of ferrite magnets started in the 40’s, but they have been available in the market since the 50’s.
They are obtained from iron oxides and from strontium or barium carbonate: these raw materials are plentiful on Earth, so availability of ferrite is rather high. The raw materials are mixed together, granulated, and thermally treated to get finally to the hexaferrite phase (SrFe12O19 or BaFe12O19). This granulate is then ground to a powder and strong permanent ferrite magnets are produced through a sintering process.
The Production of Permanent Ferrite Magnets
Pressing is performed under magnetic field (to maximize anisotropy of the magnet) or not (isotropic magnets) and can be wet or dry; finally, the product is sintered in an oxidizing atmosphere. Our magnets are available in both oriented (anisotropic) and non-oriented (isotropic) grades.
The great change of permanent ferrite magnets, which makes these magnets very common still today, was not the high remanence or high energy product but a reversible behavior of B versus H in the 2nd quadrant of the hysteresis loop.
The 2nd quadrant is the part of the hysteresis loop where magnets usually “work” in a device, that is where they supply energy to perform a reversible B versus H loop. This means that in such part of the loop the magnet can be partially re-magnetized or demagnetized, which usually occurs in a device without losing properties. It can be now understood the reason of ferrite success in the 50’s when only Alnico magnet, with its strongly reversible behavior, was predominant in industry.