Neodymium magnets are rare earth magnets made from neodymium, iron, and boron. This type of magnet was first developed by General Motors in 1982. There are two different processes used to produce neodymium magnets; classic process and fast compaction.
The classical process for the production of neodymium magnets is carried out through powder metallurgy or sintered magnetic processes. This process requires that neodymium, iron, and boron be melted down and discharged into ingots.
After these ingots are cooled they turn into fine particle strength. Particles undergo liquid phase sintering which causes the particles to magnetically straighten. After the particles are aligned, they are simultaneously heated and compressed to produce a magnet.
Quick solidification is carried out by taking the Nd-Fe-B alloy and melting the thin tape. Ribbons produced through the melting spinning process have randomly oriented granules. The tape is then crushed into small particles. The polymer is then added to the particles and the mixture is injected formed or compressed into a bonded magnet.
Around 50,000 to 55,500 tons of neodymium magnets are produced each year. This magnet is used in MRI machines, hard drives, loudspeakers, electric motors, and other applications. For example, the Toyota Prius uses 1 kilogram of neodymium to produce a motor in a car. Special care needs to be taken when handling neodymium magnets because of magnetic strength.