Bonded NdFeB magnets, bonded neodymium magnets, are those neodymium rare earth magnets manufactured by molding process. Rapid quenched NdFeB magnetic powders compounded with resin binders (epoxy, Nylon or PPS) are compacted and transformed into various shaped magnets using a compression or injection mold, finished magnets are usually plated with epoxy coating for corrosion protection. Bonded NdFeB magnets have advantages of complex shapes, high dimensional accuracy, uniform magnetic properties and diverse magnetization patterns. They are widely used in small & micro motors (spindle motors, linear motors, synchronous motors, DC & BLDC motors, etc.) and various sensors.
Bonded NdFeB Magnets’ Grades, Magnetic Properties
| Magnet Grade[1] |
Max. Energy Product (BH)max |
Residual Induction Br |
Coercive Force Hcb |
Intrinsic Coercivity Hcj |
RTC of Br α(Br)[2] |
Max. Operating Temp.[3] |
Density ρ |
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| MGOe | kJ/m3 | kGs | T | kOe | kA/m | kOe | kA/m | %/°C | °C | g/cm3 | |
| BN2 | 1.9-3.0 | 15-24 | 3.0-3.8 | 0.30-0.38 | 2.0-3.2 | 159-255 | 5-8 | 398-637 | -0.11 | 160 | 5.0-5.5 |
| BN3 | 2.6-3.6 | 21-29 | 3.5-4.3 | 0.35-0.43 | 2.4-3.3 | 191-263 | 5-8 | 398-637 | -0.11 | 160 | 4.8-5.3 |
| BN4 | 3.5-4.5 | 28-36 | 4.2-5.0 | 0.42-0.50 | 2.8-3.6 | 223-287 | 5-8 | 398-637 | -0.11 | 160 | 5.2-5.7 |
| BN5 | 4.8-5.5 | 38-44 | 4.8-5.5 | 0.48-0.55 | 3.2-4.0 | 255-318 | 5-8 | 398-637 | -0.11 | 160 | 5.4-5.8 |
| BN6 | 5.9-6.8 | 47-54 | 5.3-6.0 | 0.53-0.60 | 3.7-4.6 | 295-366 | 6-9 | 478-716 | -0.11 | 160 | 5.7-6.0 |
| BN7 | 7.0-8.0 | 56-64 | 5.8-6.5 | 0.58-0.65 | 4.4-5.2 | 350-414 | 6-9 | 478-716 | -0.11 | 160 | 5.8-6.1 |
| BN8 | 7.8-8.8 | 62-70 | 6.2-6.8 | 0.62-0.68 | 5.0-5.8 | 398-462 | 8-10 | 637-796 | -0.11 | 160 | 5.9-6.2 |
| BN8H | 7.5-8.5 | 60-68 | 6.0-6.6 | 0.60-0.66 | 4.8-5.8 | 382-462 | 10-13 | 796-1035 | -0.10 | 180 | 5.9-6.2 |
| BN9 | 8.6-9.3 | 68-74 | 6.3-6.9 | 0.63-0.69 | 5.0-5.8 | 398-462 | 8-10 | 637-796 | -0.11 | 160 | 5.9-6.2 |
| BN10 | 9.0-9.7 | 72-77 | 6.5-7.1 | 0.65-0.71 | 5.2-6.0 | 414-478 | 8-10 | 637-796 | -0.12 | 160 | 5.9-6.2 |
| BN10H | 8.8-9.5 | 70-76 | 6.2-6.8 | 0.62-0.68 | 5.4-6.0 | 430-478 | 11-14 | 875-1115 | -0.10 | 180 | 5.9-6.2 |
| BN11 | 9.8-10.5 | 78-84 | 6.7-7.3 | 0.67-0.73 | 5.3-6.0 | 422-478 | 8-11 | 637-875 | -0.12 | 160 | 5.9-6.2 |
| BN12 | 10.0-11.0 | 80-88 | 7.0-7.6 | 0.70-0.76 | 5.5-6.5 | 438-517 | 8-11 | 637-875 | -0.12 | 160 | 5.9-6.2 |
[1] In a bonded NdFeB magnet grade code, “BN” means it is a bonded neodymium magnet, the following number is typical (BH)max value of this bonded NdFeB magnet, the end with “H” (abbr. for high, regular is default) indicates intrinsic coercivity class of this bonded NdFeB magnet.
[2] Typical reversible temperature coefficient (RTC) of Br [α(Br)] between 20 and 100 °C (68-212 °F).
[3] Maximum operating temperature is strongly related to the load line/Pc (permeance coefficient) and operating environment of a bonded NdFeB magnet.
* The values in this sheet are for reference only, bonded NdFeB magnets can be tailored as per customers’ specific requirements.