NdFeB Magnets
Neodymium magnets, also known as NdFeB magnets or Neo magnets are the strongest and most affordable type of rare earth permanent magnet. They have the high remanence, high coercive, high energy product & high performance ratio which make neodymium magnets have been replacing Alnico and ferrite magnets in many applications where requiring powerful magnets. Their greater strength allows smaller and lighter magnets to be used for a given application. So the neodymium magnets are also called ‘the king of magnet’.
The main composition of Neodymium magnets is Nd2Fe14B, is easy to corrosion. In particular, corrosion along grain boundaries may cause deterioration of a sintered magnet. So, in order to protect neodymium magnet, we supply protective surface treatments such as gold, nickel, zinc, epoxy and so on.
Sintered NdFeB magnetic properties
Magnetic characteristics and physical properties of sintered NdFeB magnet
|
Grade |
Br （mT / kGs) |
Hcb （kA/m/ kOe) |
Hcj (kA/m / kOe) |
（ BH ）max （kJ/m3 /MGOe) |
(Tw) |
|
N35 |
1170-1220(11.7-12.2) |
≥ 868( ≥ 10.9) |
≥ 955( ≥ 12) |
263-287(33-36) |
80 ℃ |
|
N38 |
1220-1250(12.2-12.5) |
≥ 899( ≥ 11.3) |
≥ 955( ≥ 12) |
287-310(36-39) |
80 ℃ |
|
N40 |
1250-1280(12.5-12.8) |
≥ 907( ≥ 11.4) |
≥ 955 ( ≥ 12) |
302-326(38-41) |
80 ℃ |
|
N42 |
1280-1320(12.8-13.2) |
≥ 915( ≥ 11.5) |
≥ 955( ≥ 12) |
318-342(40-43) |
80 ℃ |
|
N45 |
1320-1380(13.2-13.8) |
≥ 923( ≥ 11.6) |
≥ 955 ( ≥ 12) |
342-366(43-46) |
80 ℃ |
|
N48 |
1380-1420(13.8-14.2) |
≥ 923( ≥ 11.6) |
≥ 876( ≥ 12) |
366-390(46-49) |
80 ℃ |
|
N50 |
1400-1450(14.0-14.5) |
≥ 796( ≥ 10.0) |
≥ 876( ≥ 11) |
382-406(48-51) |
60 ℃ |
|
N52 |
1430-1480(14.3-14.8) |
≥ 796( ≥ 10.0) |
≥ 876( ≥ 11) |
398-422(50-53) |
60 ℃ |
|
35M |
1170-1220(11.7-12.2) |
≥ 868( ≥ 10.9) |
≥ 1114( ≥ 14) |
263-287(33-36) |
100 ℃ |
|
38M |
1220-1250(12.2-12.5) |
≥ 899( ≥ 11.3) |
≥ 1114( ≥ 14) |
287-310(36-39) |
100 ℃ |
|
40M |
1250-1280(12.5-12.8) |
≥ 923( ≥ 11.6) |
≥ 1114( ≥ 14) |
302-326(38-41) |
100 ℃ |
|
42M |
1280-1320(12.8-13.2) |
≥ 955( ≥ 12.0) |
≥ 1114( ≥ 14) |
318-342(40-43) |
100 ℃ |
|
45M |
1320-1380(13.2-13.8) |
≥ 995( ≥ 12.5) |
≥ 1114 ( ≥ 14) |
342-366 (43-46) |
100 ℃ |
|
48M |
1360-1430(13.6-14.3) |
≥ 1027( ≥ 12.9) |
≥ 1114( ≥ 14) |
366-390(46-49) |
100 ℃ |
|
50M |
1400-1450(14.0-14.5) |
≥ 1033 ( ≥ 13.0) |
≥ 1114( ≥ 14) |
382-406(48-51) |
100 ℃ |
|
30H |
1080-1130(10.8-11.3) |
≥ 796 ( ≥ 10.0) |
≥ 1353( ≥ 17) |
223-247(28-31) |
120 ℃ |
|
33H |
1130-1170(11.3-11.7) |
≥ 836 ( ≥ 10.5) |
≥ 1353( ≥ 17) |
247-271(31-34) |
120 ℃ |
|
35H |
1170-1220(11.7-12.2) |
≥ 868 ( ≥ 10.9) |
≥ 1353( ≥ 17) |
263-287(33-36) |
120 ℃ |
|
38H |
1220-1250(12.2-12.5) |
≥ 899 ( ≥ 11.3) |
≥ 1353 ( ≥ 17) |
287-310(36-39) |
120 ℃ |
|
40H |
1250-1280(12.5-12.8) |
≥ 923( ≥ 11.6) |
≥ 1353( ≥ 17) |
302-326(38-41) |
120 ℃ |
|
42H |
1280-1320(12.8-13.2) |
≥ 955 ( ≥ 12.0) |
≥ 1353( ≥ 17) |
318-342(40-43) |
120 ℃ |
|
45H |
1300-1360(13-13.6) |
≥ 963( ≥ 12.1) |
≥ 1353 ( ≥ 17) |
326-358(43-46) |
120 ℃ |
|
48H |
1370-1430(13.7-14.3) |
≥ 995( ≥ 12.5) |
≥ 1353( ≥ 17) |
366-390(46-49) |
120 ℃ |
|
30SH |
1080-1130(10.8-11.3) |
≥ 804( ≥ 10.1) |
≥ 1592( ≥ 20) |
223-247(28-31) |
150 ℃ |
|
33SH |
1130-1170(11.3-11.7) |
≥ 844( ≥ 10.6) |
≥ 1592( ≥ 20) |
247-271(31-34) |
150 ℃ |
|
35SH |
1170-1220(11.7-12.2) |
≥ 876 ( ≥ 11.0) |
≥ 1592( ≥ 20) |
263-287(33-36) |
150 ℃ |
|
38SH |
1220-1250(12.2-12.5) |
≥ 907( ≥ 11.4) |
≥ 1592( ≥ 20) |
287-310(36-39) |
150 ℃ |
|
40SH |
1240-1280(12.5-12.8) |
≥ 939( ≥ 11.8) |
≥ 1592( ≥ 20) |
302-326(38-41) |
150 ℃ |
|
42SH |
1280-1320(12.8-13.2) |
≥ 987 ( ≥ 12.4) |
≥ 1592 ( ≥ 20) |
318-342(40-43) |
150 ℃ |
|
45SH |
1320-1380(13.2-13.8) |
≥ 1003 ( ≥ 12.6) |
≥ 1592( ≥ 20) |
342-366 (43-46) |
150 ℃ |
|
28UH |
1020-1080(10.2-10.8) |
≥ 764 ( ≥ 9.6) |
≥ 1990 ( ≥ 25) |
207-231(26-29) |
180 ℃ |
|
30UH |
1080-1130(10.8-11.3) |
≥ 812( ≥ 10.2) |
≥ 1990( ≥ 25) |
223-247(28-31) |
180 ℃ |
|
33UH |
1130-1170(11.3-11.7) |
≥ 852( ≥ 10.7) |
≥ 1990 ( ≥ 25) |
247-271(31-34) |
180 ℃ |
|
35UH |
1180-1220(11.8-12.2) |
≥ 860 ( ≥ 10.8) |
≥ 1990( ≥ 25) |
263-287(33-36) |
180 ℃ |
|
38UH |
1220-1250(12.2-12.5) |
≥ 876 ( ≥ 11.0) |
≥ 1990( ≥ 25) |
287-310(36-39) |
180 ℃ |
|
40UH |
1240-1280(12.5-12.8) |
≥ 899( ≥ 11.3) |
≥ 1990( ≥ 25) |
302-326(38-41) |
180 ℃ |
|
28EH |
1040-1090(10.4-10.9) |
≥ 780( ≥ 9.8) |
≥ 2388( ≥ 30) |
207-231(26-29) |
200 ℃ |
|
30EH |
1080-1130(10.8-11.3) |
≥ 812 ( ≥ 10.2) |
≥ 2388 ( ≥ 30) |
223-247 (28-31) |
200 ℃ |
|
33EH |
1130-1170(11.3-11.7) |
≥ 836 ( ≥ 10.5) |
≥ 2388 ( ≥ 30) |
247-271 (31-34) |
200 ℃ |
|
35EH |
1170-1220(11.7-12.2) |
≥ 876 ( ≥ 11.0) |
≥ 2388( ≥ 30) |
263-287(33-36) |
200 ℃ |
|
28AH |
1040-1090(10.4-10.9) |
≥ 787 ( ≥ 9.9) |
≥ 2624( ≥ 33) |
207-231 (26-29) |
230 ℃ |
|
30AH |
1080-1130(10.8-11.3) |
≥ 819 ( ≥ 10.3) |
≥ 2624( ≥ 33) |
223-247 (28-31) |
230 ℃ |
|
33Ah |
1130-1170(11.3-11.7) |
≥ 843 ( ≥ 10.6) |
≥ 2624( ≥ 33) |
247-271 (31-34) |
230 ℃ |
Surface Protection and coatings
|
Surface |
Type |
Minimal layer thickness |
Surface Color |
Remarks |
|
Passivation |
|
<=1µ |
Silver grey |
Temperary Protection |
|
Nickel coating |
Ni+Ni |
10-20µ |
Silver semibright |
Excellent resistance to humid atmosphere |
|
Ni+Cu+Ni |
Superior resistance to humid atmosphere |
|||
|
Zinc coating |
Zn |
8-20µ |
Blue whiteshining color shining |
Good resistance to salt spray |
|
C-Zn |
Excellent resistance to salt spray |
|||
|
Tin coating |
Ni+Cu+Sn |
15-20µ |
Silver semibright |
Superior resistance to humid atmosphere |
|
Gold coating |
Ni+Cu+Au |
10-20µ |
Gold shining |
Superior resistance to humid atmosphere |
|
Cupper coating |
Ni+Cu |
10-20µ |
Gold shining |
Temporary treatment |
|
Epoxy |
Ni+Cu+Epoxy |
15-25µ |
Black |
Excellent climatic and salt spray resistance |
|
Zn+Epoxy |
||||
|
Chemical Coating |
Ni |
10-20µ |
Silver semibright |
Excellent resistance to humid atmosphere |
NdFeB Physical Properties
|
Temp.Coeff.of Br: |
-0.12-0.10%/°C |
Temp.Coeff.of iHc: |
-0.60%/°C |
|
Density: |
7.4.5-7.55g/cm3 |
Curie Temperature: |
310-370°C |
|
Vickers Hardness: |
600HV |
Electrical Resistivity: |
160 |
|
Tensile Strength: |
8kg/mm2 |
Flexural Strength: |
25kg/mm |
|
Specific Heat: |
0.12kcal/(kg.°C) |
Coef.of Thermal Expansion: |
4×10-6 |
|
Thermal conductivity: |
7.7kcal/m.h.°C |
||
|
Young’s Modulus: |
1.6×1011N/m2 |
Rigidity: |
0.64N/m2 |
|
Poisson’s Ratio: |
0.24 |
Compressibility: |
9.8×10-12 m2/N |
Tags: NdFeB Magnets, Neocube, Neodymium Magnets, Permanent Magnets, Rare Earth Magnets, SmCo Magnets
