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). 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. Energy product range from 28 MGOe to about 52 MGOe. ndfeb, ndfeb magnet, sintered ndfeb

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

Both NdFeB and SmCo are available in sintered as well as bonded forms. Sintered NdFeB parts however, will produce the highest magnetic properties. NdFeB is sensitive to heat and should not be used in the environments that exceed 200^oC. Bonded NdFeB 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. ndfeb, ndfeb magnet

Bonded NdFeB Magnets Bonded NdFeB magnets are manufactured by binding rapid-quenching NdFeB powder. The powder is mixed with resin to form a magnet by compression molding with epoxy or infection molding with nylon. The latter technique is particular effective in large volume production, though the magnetic value of products is lower than those made with compression molding because of their relatively lower density. Various shapes of high dimensional accuracy can be produced without further processing. Surface is treated by epoxy coating or nickel-plating to prevent corrosion bonded magnet, bonded ndfeb magnet Other Properties of NdFeB Bonded Magnets Hybrid magnets to create different magnetic properties With different ratio of additives to NdFeB powder, magnetic properties of hybrid NdFeB magnets can be tuned in a wide range. Once the ratio is fixed, magnetic property fluctuation can still be limited in a narrow bank. Hybrid magnets will meet customers¡¯specified properties. Characteristics for the initial magnetization of NdFeB bonded magnets   Rapidly quenched NdFeB powder used for bonded magnets is multi grain with grain size of sub-micron. Powder is isotropic in magnetic properties, which results in flat increasing of remanence and intrinsic coercivity with applied field. Magnet can only be magnetized to saturation in high fields. bonded magnet, bonded ndfeb magnet Advantages of Bonded Magnet *Produced with high efficiency, stability and repeatability. *Magnet and other part may form together in one step. *Free choice of magnetizing direction-especially for multi-polar applications *High dimensional accuracy-large quantity applications with minimum post-press machining. *Thin-wall ring and complex shape magnets. *High resistance to corrosion.

Magnetic properties of bonded NdFeB Magnets P/N Br Remanence Hcj Intrinsic Coercivity Hcb Coercive Force (BH)max. Maximum Energy Product MT kG kA/m kOe kA/m kOe KJ/m3 MGOe ndfeb-NB6 440-560 4.40-5.60 560-680 7.0-8.5 240-320 3.0-4.0 32-48 4.0-6.0 ndfeb-NB8 540-640 5.40-6.40 640-720 8.0-9.0 320-400 4.0-5.0 48-64 6.0-8.0 ndfeb-NB8M 540-620 5.40-6.20 1040-1360 13.0-17.0 384-464 4.8-5.8 56-72 7.0-9.0 ndfeb-NB10 620-700 6.20-7.00 608-800 7.6-10.0 360-456 4.5-5.7 64-80 8.0-10.0 ndfeb-NB12 690-760 6.90-7.60 640-840 8.0-10.5 400-480 5.0-6.0 80-96 10.0-12.0

Physical Chracteristics of bonded NdFeB Magnets P/N   Recoil Permeability Hs Magnetizing Field ¦¯ Density Temperature Coefficient Tc Curie Temperature K[2]   Ring Crushing Strength Coefficient of Thermal Expansion (25-200¡æ)   kA/m g/cm3 kOe α(Br)%/>oC β(Hcj)%/oC oC kg/mm2 10-6/oC ndfeb-NB6 1.22 1600 5.1-5.6 ¡Ì20 -0.14 -0.40 360 5.5 4.8 ndfeb-NB8 1.22 1600 5.4-5.8 ¡Ì20 -0.13 -0.40 360 5.5 4.8 ndfeb-NB8M 1.18 2000 5.8-6.0 ¡Ì25 -0.12 -0.38 305 5.5 4.8 ndfeb-NB10 1.22 1600 5.8-6.0 ¡Ì20 -0.11 -0.40 360 5.5 4.8 ndfeb-NB12 1.17 1600 5.9-6.1 ¡Ì20 -0.11 -0.41 360 5.5 4.8

Note: [1] The properties given above are typical at room temperature(23oCfor uncoated samples. [2] Ring Crushing Strength K is defined as follows, with the force applying along a diameter of magnet ring and P is the value at which the first crack appears. K=P(D-T)/LT2 K-Ring Crushing Strength(kg/mm2)   P-Load on magnet ring(kg)  D-Outer diameter(mm)   T-Ring thickness(mm) L-Height of the ring(mm)

Demagnetization Curves of Bonded NdFeB Magnets

Safety Notes for the Use and Storage of Bonded Magnets.   *Do not place magnets near person wearing electrical medical equipment.such as pacemaker,because the magnet may result in malfunction of the equipment and endanger person’s life. bonded magnet, bonded ndfeb magnet   *Keep magnets away from magnetic memory media or other magnetic field sensitive devices such as magnetic cards.tapes,floppy disks,hard disk drivers,and watches.Otherwise information stored in the media or the devices may be damaged. *Big block of magnet will strongly attract each other or attract iron steel pieces,which may cause serious injure to person.   *Relatively weak in strength,bonded magnets may break into pieces when collide with other materials.Be careful in assembling magnets and prevent the finy fragments from entering into eyes or cause other injuries.   *Keep magnets in good condition and avoid following environment in case that magnets become rust or weaken in mechanical or magnetic strength. bonded magnet, bonded ndfeb magnet   A.   With acid,alkali,organic solvent or electrolytes.   B.     Immersed in water or in oil.   C.     Space filled with hydrogen.   D.     Space filled with corrosive gases such as Cl2,NH3,Nox,etc.   E.     With radioactive rays.