SinteredNeodymium Magnet , which is also known as NdFeB or Neo Magnet made from an alloy of neodymium,Iron and boron to form the Nd2Fe14B tetragonal crystallline structure. Neodymium Magnet has replaced other types of magnets in many applications in modern products that require strong permanent magnets.

  • Neodymium Magnet is the strongest Magnet, it makes Neodymium magnet can be produced to smaller to reach the requirement on magnetic power comparing with other permanent magnets. And because of this, neodymium magnet has replaced other types of magnets in many applications.
  • Sintered Neodymium Magnet tends to be vulnerable to corrosion,espcially along grain boundaries of a sintered magnet. This type of corrosion can cause serious deterioration, incldeing crumbling of a magnet into a powder of small magetic particles,or spalling of a surface layer.
  • Sintered Neodymium Magnet is only anisotropic, they are oriented (magnetic direction) during pressing process. It makes sintered Neodymium magnet cannot be a complex magnetic direction part.
  • Sintered Neodymium has the greater force, it makes Sintered Neodymium has a big Hazards.Neoymium Magnets larger than a few cubic centimeters are strong enough to cause injuries to body parts pinched between two magnets,or a magnet and a metal surface,even causing broken bones. The stronger magnetic fields can be hazardous to mechanical and electronic devices, as the can erase magnetic media such as floppy disks and crdit cards, and magnetize watches and the shadow masks of CRT type monitors at a greater distance than other types of magnet.

Applications

Head actuators for computer hard disks, Magnetic resonance imaging (MRI), Magnetic guitar pickups, Loudspeakers and headphones, Magnetic bearings and couplings,
Electric motors, Cordless tools, Servo motors, Lifting and compressor motors, Synchronous motors, Spindle and stepper motors, Electrical power steering, Drive motors for hybrid and electric vehicles, Actuators, Computer rigid disc drives, Linear actuators printers, Speakers, Microphone assemblies, Separators, Automotive starters

Typical Magnetic Properties

TYPICAL MAGNETIC PROPETIES OF SINTERED ALNICO MAGNET
(US STANDARD)
GradeResidual induction(Br)Coercive Force(Hcb)Coercive Force(Hcj)(BH)maxMax.Operating
Temperature
Br:Residual induction /Hcb:Coersive Force /Hcj:intrinsic Coersive Force /(BH)max:Max Energy Product
 kGs(mT)kA/m(kOe)kA/m(kOe)kJ/M3(MGOe)°C
N271030-1080≥ 796(≥10.0)≥955(≥12)199-231(25-29)80
N301080-1130≥796(≥10.0)≥955(≥12)223-247(28-31)80
N331130-1170≥836(≥10.5)≥955(≥12)247-271(31-34)80
N351170-1220≥868(≥10.9)≥955(≥12)263-287(33-36)80
N381220-1250≥899(≥11.3)≥955(≥12)287-310(36-39)80
N401250-1280≥907(≥11.4)≥955(≥12)302-326(38-41)80
N421280-1320≥915(≥11.5)≥955(≥12)318-342(40-43)80
N451320-1380≥923(≥11.6)≥955(≥12)342-366(43-46)80
N481380-1420≥923(≥11.6)≥876(≥11)366-390(46-49)80
N501400-1450≥ 796(≥10.0)≥876(≥11)382-406(48-51)80
N521430-1480≥ 796(≥10.0)≥876(≥11)398-422(50-53)80
N30M1080-1130≥ 796(≥10.0)≥1114(≥14)223-247(28-31)100
N33M1130-1170≥836(≥10.5)≥1114(≥14)247-263(31-33)100
N35M1170-1220≥868(≥10.9)≥1114(≥14)263-287(33-36)100
N38M1220-1250≥899(≥11.3)≥1114(≥14)287-310(36-39)100
N40M1250-1280≥923(≥11.6)≥1114(≥14)302-326(38-41)100
N42M1280-1320≥955(≥12.0)≥1114(≥14)318-342(40-43)100
N45M1320-1380≥995(≥12.5)≥1114(≥14)342-366(43-46)100
N48M1360-1430≥1027(≥12.9)≥1114(≥14)366-390(46-49)100
N50M1400-1450≥1033(≥13.0)≥1114(≥14)382-406(48-51)100
N30H1080-1130≥796(≥10.0)≥1353(≥17)318-342(40-43)120
N33H1130-1170≥836(≥10.5)≥1353(≥17)247-271(31-34)120
N35H1170-1220≥868(≥10.9)≥1353(≥17)263-287(33-36)120
N38H1220-1250≥899(≥11.3)≥1353(≥17)287-310(36-39)120
N40H1250-1280≥923(≥11.6)≥1353(≥17)302-326(38-41)120
N42H1280-1320≥955(≥12.0)≥1353(≥17)318-342(40-43)120
N45H1300-1360≥963(≥12.1)≥1353(≥17)326-358(43-46)120
N48H1370-1430≥995(≥12.5)≥1353(≥17)366-390(46-49)120
N30SH1080-1130≥804(≥10.1)≥1592(≥20)223-247(28-31)150
N33SH1130-1170≥844(≥10.6)≥1592(≥20)247-271(31-34)150
N35SH1170-1220≥876(≥11.0)≥1592(≥20)263-287(33-36)150
N38SH1220-1250≥907(≥11.4)≥1592(≥20)287-310(36-39)150
N40SH1250-1280≥939(≥11.8)≥1592(≥20)302-326(38-41)150
N42SH1280-1320≥987(≥12.4)≥1592(≥20)318-342(40-43)150
N45SH1320-1380≥1003(≥12.6)≥1592(≥20)342-366(43-46)150
N28UH1020-1080≥764(≥9.6)≥1990(≥25)207-231(26-29)180
N30UH1080-1130≥812(≥10.2)≥1990(≥25)223-247(28-31)180
N33UH1130-1170≥852(≥10.7)≥1990(≥25)247-271(31-34)180
N35UH1180-1220≥860(≥10.8)≥1990(≥25)263-287(33-36)180
N38UH1220-1250≥876(≥11.0)≥1990(≥25)287-310(36-39)180
N40UH1240-1280≥899(≥11.3)≥1990(≥25)302-326(38-41)180
N28EH1040-1090≥780(≥9.8)≥2388(≥30)207-231(26-29)200
N30EH1080-1130≥812(≥10.2)≥2388(≥30)223-247(28-31)200
N33EH1130-1170≥836(≥10.5)≥2388(≥30)247-271(31-34)200
N35EH1170-1220≥876(≥11.0)≥2388(≥30)263-287(33-36)200
N38EH1220-1250≥899(≥11.3)≥2388(≥30)287-310(36-39)200
Reversible Temperature Coefficients(0~100°C)
Intrinsic Coercive Force (Hci)Induction Br (G)Intrinsic Coercivity Hci (Oe)
α = Δ Br / Δ T * 100 (Br @ 20°C) [ΔT = 20°C – 100°C]

β = Δ Hci / Δ T * 100 (Hci @ 20°C) [ΔT = 20°C – 100°C]
(kOe)(%)(%)
11-0.12-0.07
12-0.12-0.07
14-0.12-0.65
17-0.11-0.65
20-0.11-0.60
25-0.10-0.55
30-0.10-0.50
35-0.09-0.40
Neodymium Magnet-Physical Properties
PropertyUnitValues
Br:Residual induction /Hcb:Coersive Force /Hcj:intrinsic Coersive Force /(BH)max:Max Energy Product
Vickers HardnessHv≥550
Densityg/cm3≥7.4
Curie Temp Tc°C312 – 380
Curie Temp Tf°F593 – 716
Specific ResistanceμΩ·Cm150
Bending StrengthMpa250
Compressive StrengthMpa1000~1100
Thermal Expansion Parallel (∥)
to Orientation (M)
°C-1(3-4) x 106
Thermal Expansion
Perpendicular (⊥) to Orientation (M)
°C-1-(1-3) x 10-6
Young’s Moduluskg/mm21.7 x 104

MMPA-Alnico document