Neodymium magnets are the best irreversible magnets commercially offered, anywhere in the world. resistance to demagnetisation when contrasted to ferrite, alnico and even samarium-cobalt magnets.
✧ Neodymium magnets VS conventional ferrite magnets
Ferrite magnets are non-metallic material magnets based on triiron tetroxide (fixed mass ratio of iron oxide to ferrous oxide). The main disadvantage of these magnets is that they cannot be forged at will.
Neodymium magnets not only have excellent magnetic power, but also have good mechanical properties due to the fusion of metals, and can be easily processed into various shapes to suit many different needs. The disadvantage is that the metal monomers in neodymium magnets are easy to rust and deteriorate, so the surface is also often plated with nickel, chromium, zinc, tin, etc. to prevent rust.
✧ Composition of neodymium magnet
Neodymium magnets are made of neodymium, iron and boron fused together, usually written as Nd2Fe14B. Because of the fixed composition and the ability to form tetragonal crystals, neodymium magnets can be considered purely from a chemical point of view. 1982, Makoto Sagawa of Sumitomo Special Metals developed neodymium magnets for the first time. Since then, Nd-Fe-B magnets have been gradually eliminated from ferrite magnets.
✧ How are neodymium magnets made?
STEP 1 - First of all, all the elements to make the chosen quality of magnet are placed into a vacuum cleaner induction furnace, heated as well as thawed to develop the alloy product. This mix is then cooled down to develop ingots before being ground right into small grains in a jet mill.
STEP 2 - The super-fine powder is then pressed in a mould as well as at the same time magnetic energy is applied to the mould. Magnetism comes from a coil of cable that acts as a magnet when an electric current is passed through it. When the particle framework of the magnet matches the instructions of magnetism, this is called an anisotropic magnet.
STEP 3 - This isn't the end of the procedure, instead, at this moment the magnetised material is demagnetized and will certainly be magnetised later while doing so. The next step is for the material to be heated up, practically till melting point in a procedure called The following action is for the product to be heated up, almost till melting point in a procedure called sintering which makes the powdered magnet bits fuse together. This procedure happens in an oxygen-free, inert setting.
STEP 4 - Virtually there, the heated material gets rapidly cooled down using a method known as quenching. This rapid cooling process reduces areas of bad magnetism and also increases performance.
STEP 5 - Due to the fact that neodymium magnets are so hard, making them susceptible to damaging and damaging, they have to be coated, cleaned, dried out, and also plated. There are many various kinds of finish that are made use of with neodymium magnets, one of the most typical being a nickel-copper-nickel mix but they can be coated in other metals and also rubber or PTFE.
STEP6 - As soon as plated, the finished product is re-magnetised by putting it inside a coil, which, when electrical current is travelled through it generates a magnetic field three times more powerful than the necessary toughness of the magnet. This is such an effective procedure that if the magnet is not kept in the location it can be flung from the coil-like a bullet.
AH MAGNET is an IATF16949, ISO9001, ISO14001 and ISO45001 accredited manufacturer of all kinds of high performance neodymium magnets and magnetic assemblies with over 30 years of experience in the field. If you are interested in neodymium magnets, please feel free to contact us!
Post time: Nov-02-2022