Sintered NdFeB Magnets

NdFeB magnets, also known as neodymium magnets, have very strong magnetic properties. NdFeB magnets are a type of rare earth permanent magnets and belong to permanent magnets. Another common rare earth magnet is samarium cobalt magnets.

Compared with other permanent magnet materials, sintered neodymium magnets have outstanding advantages in magnetic properties. It has extremely high magnetic energy product, coercive force and remanence. At the same time, it has excellent mechanical properties and is easy to process. These excellent properties make sintered NdFeB permanent magnets widely used in modern industry and electronic technology. It is widely used in permanent magnet motors, speakers, magnetic separators, computer disk drives, and magnetic resonance imaging equipment. In 2000, the total output value of rare earth permanent magnets exceeded that of ferrites for the first time. In 2010, the output value of sintered NdFeB permanent magnets exceeded that of ferrites, becoming the veritable “protagonist” of the permanent magnet industry.

LD Magnet has been committed to the production and processing of NdFeB magnets for many years. We can not only produce NdFeB magnets of conventional shapes, but also customize NdFeB magnets of various unconventional shapes and sizes.

Some typical NdFeB magnet shapes

NdFeB Disc Magnets

NdFeB Block Magnets

NdFeB Ring Magnets

NdFeB Cylindrical Magnets

NdFeB Arc magnet

NdFeB magnets with countersunk hole

Special Shape NdFeB Magnets

Magnetic Properties of Sintered Neodymium Magnets

Grade remanence Coercive force intrinsic coercive force Maximum energy product HIGHEST WORKING TEMPERATURE Density
Br Hcb Hcj (BH)max
T kGs kA/m kOe kA/m kOe kJ/m3 MGOe ℃ g/cm3
N30 1.08-1.13 10.8-11.3 ≥798 ≥10.0 ≥955 ≥12 223-247 28-31 80 ≥7.5
N33 1.13-1.17 11.3-11.7 ≥836 ≥10.5 ≥955 ≥12 247-271 31-34 80 ≥7.5
N35 1.17-1.22 11.7-12.2 ≥868 ≥10.9 ≥955 ≥12 263-287 33-36 80 ≥7.5
N38 1.22-1.25 12.2-12.5 ≥899 ≥11.3 ≥955 ≥12 287-310 36-39 80 ≥7.5
N40 1.25-1.28 12.5-12.8 ≥907 ≥11.4 ≥955 ≥12 302-326 38-41 80 ≥7.5
N42 1.28-1.32 12.8-13.2 ≥915 ≥11.5 ≥955 ≥12 318-342 40-43 80 ≥7.5
N45 1.32-1.38 13.2-13.8 ≥923 ≥11.6 ≥955 ≥12 342-366 43-46 80 ≥7.5
N48 1.38-1.42 13.8-14.2 ≥923 ≥11.6 ≥955 ≥12 366-390 46-49 80 ≥7.5
N50 1.40-1.45 14.0-14.5 ≥796 ≥10.0 ≥876 ≥11 382-406 48-51 80 ≥7.5
N52 1.43-1.48 14.3-14.8 ≥796 ≥10.0 ≥876 ≥11 398-422 50-53 80 ≥7.5
N55 1.46-1.52 14.6-15.2 ≥796 ≥10.0 ≥876 ≥11 414-430 52-54 80 ≥7.5
N35M 1.17-1.22 11.7-12.2 ≥868 ≥10.9 ≥1114 ≥14 263-287 33-36 100 ≥7.5
N38M 1.22-1.25 12.2-12.5 ≥899 ≥11.3 ≥1114 ≥14 287-310 36-39 100 ≥7.5
N40M 1.25-1.28 12.5-12.8 ≥923 ≥11.6 ≥1114 ≥14 302-326 38-41 100 ≥7.5
N42M 1.28-1.32 12.8-13.2 ≥955 ≥12.0 ≥1114 ≥14 318-342 40-43 100 ≥7.5
N45M 1.32-1.38 13.2-13.8 ≥995 ≥12.5 ≥1114 ≥14 342-366 43-46 100 ≥7.5
N48M 1.37-1.43 13.7-14.3 ≥1027 ≥12.9 ≥1114 ≥14 366-390 46-49 100 ≥7.5
N50M 1.40-1.45 14.0-14.5 ≥1033 ≥13.0 ≥1114 ≥14 382-406 48-51 100 ≥7.5
N52M 1.43-1.48 14.3-14.8 ≥1050 ≥13.2 ≥1114 ≥14 398-422 50-53 100 ≥7.5
N54M 1.45-1.50 14.5-15.0 ≥1051 ≥13.2 ≥1114 ≥14 414-438 52-55 100 ≥7.5
N35H 1.17-1.22 11.7-12.2 ≥868 ≥10.9 ≥1353 ≥17 263-287 33-36 120 ≥7.5
N38H 1.22-1.25 12.2-12.5 ≥899 ≥11.3 ≥1353 ≥17 287-310 36-39 120 ≥7.5
N40H 1.25-1.28 12.5-12.8 ≥923 ≥11.6 ≥1353 ≥17 302-326 38-41 120 ≥7.5
N42H 1.28-1.32 12.8-13.2 ≥955 ≥12.0 ≥1353 ≥17 318-342 40-43 120 ≥7.5
N45H 1.32-1.36 13.2-13.6 ≥963 ≥12.1 ≥1353 ≥17 342-366 43-46 120 ≥7.5
N48H 1.37-1.43 13.7-14.3 ≥995 ≥12.5 ≥1353 ≥17 366-390 46-49 120 ≥7.5
N50H 1.40-1.45 14.0-14.5 ≥1011 ≥12.7 ≥1353 ≥17 382-406 48-51 120 ≥7.5
N52H 1.43-1.48 14.3-14.8 ≥1027 ≥12.9 ≥1353 ≥17 398-422 50-53 120 ≥7.5
N33SH 1.14-1.18 11.4-11.8 ≥852 ≥10.7 ≥1592 ≥20 247-279 31-35 150 ≥7.5
N35SH 1.17-1.22 11.7-12.2 ≥876 ≥11.0 ≥1592 ≥20 263-287 33-36 150 ≥7.5
N38SH 1.22-1.25 12.2-12.5 ≥907 ≥11.4 ≥1592 ≥20 287-310 36-39 150 ≥7.5
N40SH 1.25-1.28 12.5-12.8 ≥939 ≥11.8 ≥1592 ≥20 302-326 38-41 150 ≥7.5
N42SH 1.28-1.32 12.8-13.2 ≥987 ≥12.4 ≥1592 ≥20 318-342 40-43 150 ≥7.5
N45SH 1.32-1.38 13.2-13.8 ≥1003 ≥12.6 ≥1592 ≥20 342-366 43-46 150 ≥7.5
N48SH 1.37-1.43 13.7-14.3 ≥1027 ≥12.9 ≥1592 ≥20 366-390 46-49 150 ≥7.5
N50SH 1.40-1.45 14.0-14.5 ≥1003 ≥12.6 ≥1592 ≥20 382-406 48-51 150 ≥7.5
N28UH 1.04-1.08 10.4-10.8 ≥764 ≥9.6 ≥1990 ≥25 207-231 26-29 180 ≥7.5
N30UH 1.08-1.13 10.8-11.3 ≥812 ≥10.2 ≥1990 ≥25 223-247 28-31 180 ≥7.5
N33UH 1.13-1.17 11.3-11.7 ≥852 ≥10.7 ≥1990 ≥25 247-271 31-34 180 ≥7.5
N35UH 1.17-1.22 11.7-12.2 ≥860 ≥10.8 ≥1990 ≥25 263-287 33-36 180 ≥7.5
N38UH 1.22-1.25 12.2-12.5 ≥876 ≥11.0 ≥1990 ≥25 287-310 36-39 180 ≥7.5
N40UH 1.25-1.28 12.5-12.8 ≥899 ≥11.3 ≥1990 ≥25 302-326 38-41 180 ≥7.5
N42UH 1.28-1.32 12.8-13.2 ≥899 ≥11.3 ≥1990 ≥25 318-342 40-43 180 ≥7.5
N45UH 1.32-1.36 13.2-13.6 ≥908 ≥11.4 ≥1990 ≥25 342-366 43-46 180 ≥7.5
N48UH 1.37-1.43 13.7-14.3 ≥908 ≥11.4 ≥1990 ≥25 366-390 46-49 180 ≥7.5
N28EH 1.04-1.08 10.4-10.8 ≥780 ≥9.8 ≥2388 ≥30 207-231 26-29 200 ≥7.5
N30EH 1.08-1.13 10.8-11.3 ≥812 ≥10.2 ≥2388 ≥30 223-247 28-31 200 ≥7.5
N33EH 1.13-1.17 11.3-11.7 ≥836 ≥10.5 ≥2388 ≥30 247-271 31-34 200 ≥7.5
N35EH 1.17-1.22 11.7-12.2 ≥876 ≥11.0 ≥2388 ≥30 263-287 33-36 200 ≥7.5
N38EH 1.22-1.25 12.2-12.5 ≥899 ≥11.3 ≥2388 ≥30 287-310 36-39 200 ≥7.5
N40EH 1.25-1.28 12.5-12.8 ≥899 ≥11.3 ≥2388 ≥30 302-326 38-41 200 ≥7.5
N42EH 1.28-1.32 12.8-13.2 ≥899 ≥11.3 ≥2388 ≥30 318-342 40-43 200 ≥7.5
N45EH 1.32-1.36 13.2-13.6 ≥899 ≥11.3 ≥2388 ≥30 342-366 43-46 200 ≥7.5
N28AH 1.04-1.08 10.4-10.8 ≥787 ≥9.9 ≥2786 ≥35 207-231 26-29 230 ≥7.5
N30AH 1.08-1.13 10.8-11.3 ≥819 ≥10.3 ≥2786 ≥35 223-247 28-31 230 ≥7.5
N33AH 1.13-1.17 11.3-11.7 ≥843 ≥10.6 ≥2786 ≥35 247-271 31-34 230 ≥7.5
N35AH 1.17-1.22 11.7-12.2 ≥876 ≥11.0 ≥2786 ≥35 263-287 33-36 230 ≥7.5
N38AH 1.22-1.25 12.2-12.5 ≥899 ≥11.3 ≥2786 ≥35 287-310 36-39 230 ≥7.5
N40AH 1.26-1.31 12.6-13.1 ≥939 ≥11.8 ≥2786 ≥35 302-334 38-42 230 ≥7.5
N42AH 1.29-1.35 12.9-13.5 ≥955 ≥12.0 ≥2786 ≥35 318-350 40-44 230 ≥7.5
G48SH 1.37-1.42 13.7-14.2 >1011 >13 >1592 >20 358-390 45-49 <150 >7.5
G50SH 1.40-1.45 14.0-14.5 >1027 >13.2 >1592 >20 374-406 47-51 <150 >7.5
G52SH 1.42-1.48 14.2-14.8 >1067 >13.4 >1592 >20 390-422 49-53 <150 >7.5
G55SH 1.46-1.51 14.6-15.1 >1083 >13.6 >1592 >20 406-438 51-55 <150 >7.5
G45UH 1.33-1.38 13.3-13.8 >978 >12.4 >1990 >25 334-366 42-46 <180 >7.5
G48UH 1.37-1.42 13.7-14.2 >1027 >12.9 >1990 >25 358-390 45-49 <180 >7.5
G50UH 1.40-1.45 14.0-14.5 >1051 >13.2 >1990 >25 374-406 47-51 <180 >7.5
G52UH 1.42-1.48 14.2-14.8 >1067 >13.5 >1990 >25 390-422 49-53 <180 >7.5
G54UH 1.46-1.51 14.6-15.1 >1075 >13.5 >1990 >25 406-438 51-55 <180 >7.5
G40EH 1.26-1.31 12.6-13.1 >955 >12.0 >2388 >30 302-334 38-42 <200 >7.5
G44EH 1.29-1.35 12.6-13.1 >971 >12.2 >2388 >30 318-350 40-44 <200 >7.5
G46EH 1.33-1.38 12.6-13.1 >1011 >12.7 >2388 >30 334-366 42-46 <200 >7.5
G48EH 1.37-1.42 12.6-13.1 >1027 >12.9 >2388 >30 358-390 45-49 <200 >7.5
G50EH 1.40-1.45 12.6-13.1 >1051 >13.2 >2388 >30 374-406 47-51 <200 >7.5

General surface treatment methods for NdFeB magnets

Neodymium magnets typically require surface treatment to enhance their durability and corrosion resistance. They are prone to oxidation and can corrode easily, coatings such as nickel-copper-nickel, epoxy, or zinc are commonly applied. These treatments protect the magnet from environmental factors and help maintain its magnetic properties over time.

 

Coating Thickness (Micrometer) Color Salt Spray Test (Hours) Pressure Cooker Test (Hours)
Zn 4-15 Bright blue ≥24 –
Color-Zn 4-15 Shining color ≥48 –
Ni-Cu-Ni 5-20 Bright silver ≥48 ≥48
Electroless Ni 5-20 Dark silver ≥72 ≥48
Ni-Cu-Ni-Au 5-20 Golden ≥72 ≥96
Ni-Cu-Ni-Ag 5-20 Silver ≥72 ≥96
Ni-Cu-Ni-Sn 5-20 Silver ≥72 ≥96
Phosphate 1-3 Dark Grey – –
Aluminum 2-15 Bright silver ≥24 ≥24
Epoxy resin 10-30 Black/Grey ≥72 ≥72
Parylene 5-20 Colorless ≥96 –
Everlube 10-15 Golden yellow ≥120 ≥72
Teflon 8-15 Black ≥24 ≥24