Magnetic and Physical Characteristics
Many grades of Neodymium magnets exist to support a variety of industrial applications. The range of Neo grades typically extends from 33 MGOe to 52 MGOe. This range allows for optimizing cost, performance, and operational temperature resistance.
The typical convention for “Grade” is to use the value of the particular magnet alloy’s Energy Density or Maximum Energy Product. Often, there are letters or a two digit number suffix attached to the Grade which indicates the Intrinsic Coercive Force (Hci) level of the magnet alloy. This Hci is a good indicator of the maximum allowable temperature a particular Neo alloy can tolerate before irreversible demagnetizing occurs.
The higher the “Grade number,” the higher the Energy Density. Usually, the higher the Energy Density, the stronger the magnet, but this is very much dependent upon the magnet’s operational environment.
| * Maximum Operating Temperature for this Group is 60°C / 140°F ( L/D ≥0.7) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Dura Magnet Grade | Common Industry Notation | Residual Induction Br | Coercive Force Hc | Intrinsic Coercive Force Hci | Maximum Energy Product (BH)max |
||||
| Range | Minimum | Minimum | Range | ||||||
| k-Gauss | Tesla | k-Oersted | kA/m | k-Oersted | kA/m | MGOe | kJ/m3 | ||
| 5011 | N50 | 14.0 - 14.5 | 1.40 - 1.45 | 10.5 | 836 | 11 | 876 | 47 - 51 | 374 - 406 |
| 5211 | N52 | 14.4 -14.8 | 1.44 - 1.48 | 10.5 | 836 | 11 | 876 | 49 - 53 | 390 - 422 |
* Maximum Operating Temperature for this Group is 80°C / 176°F ( L/D ≥0.7)
Dura
Magnet
GradeCommon
Industry
NotationResidual
Induction
BrCoercive
Force
HcIntrinsic
Coercive
Force
HciMaximum
Energy
Product
(BH)max
3512 N35 11.8 - 12.3 1.18 - 1.23 10.9 868 12 955 34 - 36 263 - 287
3812 N38 12.3 - 12.6 1.23 - 1.26 11.3 899 12 955 36 - 39 287 - 311
4012 N40 12.6 - 12.9 1.26 - 1.29 11.4 907 12 955 38 - 41 302 - 327
4212 N42 12.9 - 13.3 1.29 - 1.33 11.5 915 12 955 40 - 43 318 - 342
4512 N45 13.3 - 13.7 1.33 - 1.37 11.0 876 12 955 43 - 46 342 - 366
4812 N48 13.7-14.1 1.37 - 1.41 10.5 836 12 955 45 - 49 358 - 390
| * Maximum Operating Temperature for this Group is 100°C / 212°F ( L/D ≥0.7) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Dura Magnet Grade | Common Industry Notation | Residual Induction Br | Coercive Force Hc | Intrinsic Coercive Force Hci | Maximum Energy Product (BH)max |
||||
| Range | Minimum | Minimum | Range | ||||||
| k-Gauss | Tesla | k-Oersted | kA/m | k-Oersted | kA/m | MGOe | kJ/m3 | ||
| 3314 | N33M | 11.3 - 11.8 | 1.13 - 1.18 | 10.5 | 836 | 14 | 1,114 | 31 - 34 | 247 - 271 |
| 3514 | N35M | 11.8 - 12.3 | 1.18 - 1.23 | 10.9 | 868 | 14 | 1,114 | 34 - 36 | 263 - 287 |
| 3814 | N38M | 12.3 - 12.6 | 1.23 - 1.26 | 11.3 | 899 | 14 | 1,114 | 36 - 39 | 287 - 311 |
| 4014 | N40M | 12.6 - 12.9 | 1.26 - 1.29 | 11.6 | 923 | 14 | 1,114 | 38 - 41 | 302 - 327 |
| 4214 | N42M | 12.9 - 13.3 | 1.29 - 1.33 | 12.0 | 955 | 14 | 1,114 | 40 - 43 | 318 - 342 |
| 4514 | N45M | 13.3 - 13.7 | 1.33 - 1.37 | 12.5 | 995 | 14 | 1,114 | 43 - 46 | 342 - 366 |
| 4814 | N48M | 13.7 -14.1 | 1.37 - 1.41 | 12.9 | 1,027 | 14 | 1,114 | 45 - 49 | 358 - 390 |
| 5014 | N50M | 14.0 - 14.5 | 1.40 - 1.45 | 13.0 | 1,033 | 14 | 1,114 | 47 - 51 | 374 - 406 |
* Maximum Operating Temperature for this Group is 120°C / 248°F ( L/D ≥0.7)
Dura
Magnet
GradeCommon
Industry
NotationResidual
Induction
BrCoercive
Force
HcIntrinsic
Coercive
Force
HciMaximum
Energy
Product
(BH)max
Range Minimum Minimum Range
k-Gauss Tesla k-Oersted kA/m k-Oersted kA/m MGOe kJ/m3
3017 N30H 10.8 - 11.3 1.08 - 1.13 10 796 17 1,353 28 - 31 223 - 247
3317 N33H 11.3 - 11.8 1.13 - 1.18 10.5 836 17 1,353 31 - 34 247 - 271
3517 N35H 11.8 - 12.3 1.18 - 1.23 10.9 868 17 1,353 34 - 36 263 - 287
3817 N38H 12.3 - 12.6 1.23 - 1.26 11.3 899 17 1,353 36 - 39 287 - 311
4017 N40H 12.6 - 12.9 1.26 - 1.29 11.6 923 17 1,353 38 - 41 302 - 327
4217 N42H 12.9 - 13.3 1.29 - 1.33 12 955 17 1,353 40 - 43 318 - 342
4517 N45H 13.3 - 13.7 1.3 - 1.37 12.3 979 17 1,353 43 - 46 342-366
4817 N48H 13.7 - 14.1 1.37 - 1.41 12.5 995 17 1,353 45 - 49 358-390
* Maximum Operating Temperature for this Group is 150°C / 302°F ( L/D ≥0.7)
Dura
Magnet
GradeCommon
Industry
NotationResidual
Induction
BrCoercive
Force
HcIntrinsic
Coercive
Force
HciMaximum
Energy
Product
(BH)max
Range Minimum Minimum Range
k-Gauss Tesla k-Oersted kA/m k-Oersted kA/m MGOe kJ/m3
3020 N30SH 10.8 - 11.4 1.08 - 1.14 10.1 804 20 1,592 28 - 31 223 - 247
3320 N33SH 11.4 - 11.8 1.14 - 1.18 10.6 844 20 1,592 31 - 34 247 - 271
3520 N35SH 11.8 - 12.3 1.18 - 1.23 11.0 876 20 1,592 33 - 36 263 - 287
3820 N38SH 12.3 - 12.6 1.23 - 1.26 11.4 907 20 1,592 36 - 39 287 - 311
4020 N40SH 12.6 - 12.9 1.26 - 1.29 11.6 939 20 1,592 38 - 41 302 - 326
4220 N42SH 12.9 - 13.3 1.29 - 1.33 12.4 987 20 1,592 40 - 43 318 - 342
4520 N45SH 13.3 - 13.7 1.33 - 1.37 12.6 1,003 20 1,592 42 - 46 334 - 366
* Maximum Operating Temperature for this Group is 180°C / 356°F ( L/D ≥0.7)
Dura
Magnet
GradeCommon
Industry
NotationResidual
Induction
BrCoercive
Force
HcIntrinsic
Coercive
Force
HciMaximum
Energy
Product
(BH)max
Range Minimum Minimum Range
k-Gauss Tesla k-Oersted kA/m k-Oersted kA/m MGOe kJ/m3
2825 N28UH 10.4 - 10.8 1.04 - 1.08 9.6 764 25 1,989 26 - 29 207 - 231
3025 N30UH 10.8 - 11.4 1.08 - 1.14 10.1 804 25 1,989 28 - 31 223 - 247
3325 N33UH 11.4 - 11.8 1.14 - 1.18 10.7 852 25 1,989 31 - 34 247 - 271
3525 N35UH 11.8 - 12.3 1.18 - 1.23 10.8 860 25 1,989 33 - 36 263 - 287
3825 N38UH 12.3 - 12.6 1.23 - 1.26 11.3 899 25 1,989 36 - 39 287 - 311
4025 N40UH 12.5 - 12.9 1.25 - 1.29 11.4 907 25 1,989 38 - 41 302 - 326
4225 N42UH 12.8 - 13.3 1.28 - 1.33 11.6 923 25 1,989 40 - 43 318 - 342
* Maximum Operating Temperature for this Group is 200°C / 392°F ( L/D ≥0.7)
Dura
Magnet
GradeCommon
Industry
NotationResidual
Induction
BrCoercive
Force
HcIntrinsic
Coercive
Force
HciMaximum
Energy
Product
(BH)max
Range Minimum Minimum Range
k-Gauss Tesla k-Oersted kA/m k-Oersted kA/m MGOe kJ/m3
2830 N28EH 10.4 - 10.8 1.04 - 1.08 9.8 780 30 2,388 26 - 29 207 - 231
3030 N30EH 10.8 - 11.4 1.08 - 1.14 10.1 804 30 2,388 28 - 31 223 - 247
3330 N33EH 11.4 - 11.8 1.14 - 1.18 10.3 820 30 2,388 31 - 34 247 - 271
3530 N35EH 11.7 - 12.3 1.17 - 1.23 10.5 836 30 2,388 33 - 36 263 - 287
3830 N38EH 12.2- 12.6 1.22 - 1.26 11.3 899 30 2,388 35 - 39 278 - 311
* Maximum Operating Temperature for this Group is 230°C / 446°F ( L/D ≥0.7)
Dura
Magnet
GradeCommon
Industry
NotationResidual
Induction
BrCoercive
Force
HcIntrinsic
Coercive
Force
HciMaximum
Energy
Product
(BH)max
Range Minimum Minimum Range
k-Gauss Tesla k-Oersted kA/m k-Oersted kA/m MGOe kJ/m3
2835 N28AH 10.4 - 10.9 1.04 - 1.09 9.8 780 35 2,785 26 - 29 207 - 231
3035 N30AH 10.8 - 11.3 1.08 - 1.13 10.1 804 35 2,785 28 - 31 223 - 247
3335 N33AH 11.3 - 11.8 1.13 - 1.18 10.3 820 33 2,625 31 - 34 247 - 271
3535 N35AH 11.7 - 12.3 1.17 - 1.23 10.5 836 33 2,625 33 - 36 263 - 287
| Reversible Temperature Coefficients (0°C to 100°C) | ||
|---|---|---|
| Intrinsic Coercive Force (Hci) | Induction Br (G) | Intrinsic Coercivity Hci (Oe) |
| (KOe) | (%) | (%) |
| 11 | -0.12% | -0.70% |
| 12 | -0.12% | -0.70% |
| 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% |
| 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] |
||
| Neodymium Magnets - Physical Properties | ||
|---|---|---|
| Property | Units | Values |
| Vickers Hardness | Hv | ≥550 |
| Density | g/cm3 | ≥7.4 |
| Curie Temp TC | °C | 312 - 380 |
| Curie Temp TF | °F | 593 - 716 |
| Specific Resistance | μΩ⋅Cm | 150 |
| Bending Strength | Mpa | 250 |
| Compressive Strength | Mpa | 1000~1100 |
| Thermal Expansion Parallel (∥) to Orientation (M) | °C-1 | (3-4) x 10-6 |
| Thermal Expansion Perpendicular (⊥) to Orientation (M) | °C-1 | -(1-3) x 10-6 |
| Young's Modulus | kg/mm2 | 1.7 x 104 |
The listed values are approximate and should be used as a reference. Any magnetic or physical characteristics should be substantiated before selecting a magnet material. Please engage Dura’s magnet Design / Development team before selecting a design path.
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