There are two principal neodymium magnet manufacturing methods:
Classical powder metallurgy or sintered magnet process
Rapid solidification or bonded magnet process
Bonded NdFeB Magnet is made by evenly mixing neodymium iron boron powder with resin, plastics and low melting point metal and so oncaking agents, then made the boron permanent magnet of compound neodymium iron by methods such as compressing, pushing or injecting shaping. The products take shape once, do not need processing again and can be made into various complicated forms derectly. All directions of the bonded NdFeB magnet are magnetic, and can be processed into compression moulds and injetion moulds.
Bonded NdFeB Magnets are prepared by melt spinning a thin ribbon of the NdFeB alloy. The ribbon contains randomly oriented Nd2Fe14B nano-scale grains. This ribbon is then pulverized into particles, mixed with a polymer, and either compression- or injection-molded into bonded magnets. Bonded magnets offer less flux intensity than sintered magnets, but can be net-shape formed into intricately shaped parts, as is typical with Halbach arrays or arcs, trapezoids and other shapes and assemblies (e.g. Pot Magnets, Separator Grids, etc.). There are approximately 5,500 tons of Neo bonded magnets produced each year. In addition, it is possible to hot-press the melt spun nanocrystalline particles into fully dense isotropic magnets, and then upset-forge or back-extrude these into high-energy anisotropic magnets.
Bonded magnets can be made from either hard ferrite materials or rare earth magnetic powder. They are manufactured using both injection molding and compression bonding techniques which are fully automated and are particularly suitable for high volume production.
Bonded neo powder is incorporated into numerous end market applications that utilize bonded neo magnets. These products are primarily motors and sensors used in a range of products, including computer and office equipment (e.g., hard disk drives and optical disk drive motors and fax, copier and printer stepper motors), consumer electronics (e.g., personal video recorders and mp3 music players), automotive and industrial applications (e.g., instrument panel motors, seat motors andair bag sensors) and home ventilation systems (e.g., ceiling fans).
Application of Bonded Neodymium magnets:
•DC motors (automotive starters) and other motors