Neodymium Iron Boron

About Neodymium Iron Boron Magnets

Neodymium iron boron magnets, also known as Nd2Fe14B magnets, neodymium magnets, neo magnets, Nd-Fe-B magnets, RE2TM14B magnets, or simply 2:14:1 magnets, were developed in the 1980s. Nd2Fe14B has a tetragonal crystal structure. The heavy rare earth element, dysprosium, is often added to increase intrinsic coercivity and maximum operating temperature. Small amounts of other transition metals, such as Al, Co, Cu, Nb and/or Ga, can be added to modify the microstructure to improve performance.

Key features of sintered NdFeB magnets include:

  • Highest room temperature maximum energy product, (BH)max, up to 52 MGOe
  • Relatively less expensive
  • Wide range of choices for a variety of applications

 

 

 

 

Neodymium Iron Boron Magnetic Properties

Neodymium Iron Boron Mechanical Properties

Additional Information

Although NdFeB magnets have a maximum energy product of more than 50 MGOe at room temperature, their maximum operating temperature is relative low due to low Curie temperature. When operating temperature is a concern, most customers prefer SmCo magnets, especially when the maximum operating temperature is more than 180 °C. Reversible temperature coefficient of residual induction of NdFeB magnets is around -0.11% / °C, which is about three times that for SmCo magnets. In order to avoid corrosion, surface protection is required for NdFeB magnets. Ni plating, epoxy coating and aluminum ion vapor deposition (IVD) are common types of surface treatment for NdFeB magnets. The entire magnetic circuit should be carefully considered when designing with NdFeB to make sure the working point is well above the knee point on the demagnetization curve to avoid demagnetization. Because of their high maximum energy product and reasonable cost, NdFeB magnets have found many applications including spindle and stepper motors, servomotors, compressor motors, drive motors for hybrid and electric vehicles, electric generators for wind turbines, actuators, magnetic bearings, loudspeakers, computer hard disk drives, magnetic resonance imaging (MRI), sensors, flow meter and medical devices.

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