Do you need pulling force outside, then you use best ferrite magnets. But also when you need magnets that can withstand high temperatures up to 200 ° C. Ferrite, unlike neodymium, is a lot cheaper. So if you do not need a lot of holding power, then you are the most profitable with ferrite magnets!
The different forms of ferrite magnets are more limited than those of our neodymium magnets. The magnets shown are just a selection from our range. If you want different shapes or sizes, please know that we are happy to help you.
All our modern ferrite materials are polycrystalline (consist of a large number of small crystals) and have a spinel structure. The general composition of ferrites is MeFe2O4, where Me is one or more of the divalent metal manganese, zinc, nickel, cobalt, copper, iron or magnesium. The most used ferrites are manganese zinc and nickel zinc.
The normal spinel structure consists of 32 oxygen ions and 24 cations, of which eight divalent are surrounded by 4 oxygen ions (the tetrahedron positions, A) and sixteen trivalent by 6 oxygen ions (the octahedron positions, B).
There is a strong interaction between the spin of the metal ions of the A and B positions, which are directed in the opposite direction. The magnetic fields, however, only partially cancel each other, an essential property of ferrimagnetic materials. An important fact is furthermore that the bivalent non-magnetic zinc ions can occupy the B positions of the trivalent Fe 3+, in which case the Fe 3+ ions are displaced to the A positions. By changing the ratio of the original materials, magnetic properties such as curie temperature, saturation point, and losses can be varied within very wide limits, albeit that improvement of one property is almost always at the expense of deterioration of another property. By adding very small amounts of other elements or oxides and by optimal production process settings progress is still being made in the combination of magnetic properties.