General Description NdFeB Rare Earth Magnets
Rare Earth Magnets are including Neodymium(Nd)-Iron(Fe)-Boron(B) types and Samarium(Sm)- Cobalt(Co) classes. The most commonly produced material is neodymium-iron-boron (NdFeB), a type of rare earth alloy that typically has two atoms of Neodymium (Nd), 14 atoms of Iron (Fe), and one atom of Boron (B) as its primary elements, hence their chemical composition Nd2Fe14B, which is commonly abbreviated as NdFeB. There are other elements that are used to increase the coercivity, to gain lower oxidation characteristics, and to obtain other desirable characteristics. These elements are used to "dope" the alloy and are generally found in small quantities (<10% by weight). This group of magnetic materials provides the highest available magnetic energies of any material. NdFeB magnets allow small shapes and sizes with high magnetic fields, they are energy product ranges from 26 MGOe to about 52 MGOe, with wonderful coercive force and high remanence, neodymium iron boron are less brittle than SmCo and are mechanically stronger, and the cost is much more resonable.
Super-Strength Rare Earth Magnet—Sintered NdFeB magnets, have the characteristics of:
- Extreme strong Br Resident induction
- Excellent demagnetization resistance capability
- Good Price relative to its high magnetic properties
- Coating is needed for NdFeB
Surface Treatment Method: Type Information
Metallic Zinc, Nickel, Nickel+Nickel, Copper+Nickel, Nickel+Copper+Nickel
Gold, Organic Epoxy, Nickel+Epoxy coating
Temporary Surface: Passivation
Sintered NdFeB Magnets are prone to corrosion in humid environments, additionally, they are more prone to oxidation than any other magnet alloy. So they usually need surface treatment according to customer's requirements to protect magnet. We can offer the plating included: Ni, Zn, Ni-Cu-Ni, Silver, Gold, Passivation, Epoxy Resin, etc. They are widely used in DC motors, linear motors, loud speakers, MRI, medical apparatus, transmission machine, lifting machine, and so on.
Both rare earth neodymium iron boron and samarium cobalt are available in sintered as well as bonded forms. Sintered NdFeB magnetic parts, however, will produce the highest magnetic properties. NdFeB is sensitive to heat, which should not be used in the environments that exceed 200°C. Bonded NdFeB magnets are generally low in properties due to the special process of gluing the powder in a mold. The bonded form of the material can be produced with close tolerance off tools with little or no finishing required. The sintered form usually some finishing operations in order to hold close mechanical tolerances.
Do NOT use Neodymium Iron Boron magnets under the following conditions:
- In an acidic, alkaline, or organic solvent (unless you are going to hermetically seal the magnet inside a can)
- In water or oil (unless hermetically sealed, or you are prepared to accept a limited life)
- In an electrically conductive liquid, such as electrolyte containing water
- In a hydrogen-containing atmosphere, especially at elevated temperatures. Hydrogenation, a process where the Hydrogen molecule will react with the NdFeB, will occur, causing the magnet to rapidly deteriorate
- Environments containing corrosive gasses, such as Cl, NH3, Nox, etc.
- In the path of radioactive rays