Bonded Neodymium Magnet
Bonded neodymium magnet is composed of a special form of neodymium powder with a plastic carrier material. They have lower energy product than Sintered neodymium magnet. Very complicated shapes can be produced in Bonded neodymium magnet with very close dimensions.
Manufacturing Process
Bonded neodymium magnet is produced by a special form of neodymium powder blended with a plastic carrier material, die pressed and then heated. Parts made in this way can be of complex shapes and come off the tools with close tolerances, requiring no further finish machining.
Machining
Bonded neodymium magnet is easily machined. Coolants must be used while machining this material in order to avoid spontaneous combustion of powder. Machining this material is to remove a layer of protective coating, and re-coating for corrosion resistance may be necessary.
Surface treatment
The corrosion resistance of Bonded neodymium magnet is considered poor, epoxy coating is mostly common used for bonded neodymium magnet.
Magnetizing
Bonded neodymium magnet is isotropic and can be magnetized in any direction or with multiple poles. Special magnetizing fixtures are required in order to achieve multiple pole magnetization, depending on complexity of design and production rate requirements.
Magnetic properties of Bonded neodymium magnet
Grade | Residual Induction | Coercive Force | Intrinsic Coercive Force | Maximum Energy Product | Maximum Working Temperature |
Br | Hcb | Hcj | (BH)max | Tw | |
mT | kA/m | kA/m | kJ/m3 | ||
[kGs] | [kOe] | [kOe] | [MGOe] | ||
BNP-3 | 450-510 | 199-263 | 477-597 | 24-32 | 100° |
[4.5-5.1] | [2.5-3.3] | [6.0-7.5] | [3.0-4.0] | ||
BNP-6 | 590-650 | 302-374 | 597-796 | 44-53.6 | 100° |
[5.9-6.5] | [3.8-4.7] | [7.5-10.0] | [5.5-7.0] | ||
BNP-8 | 620-670 | 390-454 | 636-796 | 60-68 | 100° |
[6.2-6.7] | 4.9-5.7 | [8.0-10.0] | [8.0-9.5] | ||
BNP-8SR | 620-660 | 405-470 | 955-1114 | 65.6-72 | 150° |
[6.2-6.6] | [5.1-5.9] | [12.0-14.0] | [8.2-9.0] | ||
BNP-9H | 650-700 | 421-484 | 915-1034 | 72-80 | 150° |
[6.5-7.0] | [5.3-6.1] | [11.5-13.0] | [9.0-10.0] | ||
BNP-10 | 680-720 | 413-477 | 636-796 | 76-84 | 100° |
[6.8-7.2] | [5.2-6.0] | [8.0-10.0] | [9.5-10.5] | ||
BNP-11 | 700-740 | 430-493 | 636-796 | 80-88 | 100° |
[7.0-7.4] | [5.4-6.2] | [8.0-10.0] | [10.0-11.0] | ||
BNP-12L | 730-770 | 366-430 | 517-637 | 84-92 | 90° |
[7.3-7.7] | [4.6-5.4] | [6.5-8.0] | [10.5-11.5] |
Physical properties of Bonded neodymium magnet
Grade | Density | Permeability | Temperature Coefficient of Br | Temperature Coefficient of Hc |
BNP-3 | 5.8-6.5g/cm3 | 1.30μ r | -0.11α(Br) %/ ℃ | -0.14α(Hc) %/ ℃ |
BNP-6 | 5.8-6.3g/cm3 | 1.30μ r | -0.11α(Br) %/ ℃ | -0.14α(Hc) %/ ℃ |
BNP-8 | 5.8-6.2g/cm3 | 1.20μ r | -0.11α(Br) %/ ℃ | -0.14α(Hc) %/ ℃ |
BNP-8SR | 5.8-6.2g/cm3 | 1.16μ r | -0.07α(Br) %/ ℃ | -0.09α(Hc) %/ ℃ |
BNP-9H | 5.8-6.2g/cm3 | 1.16μ r | -0.07α(Br) %/ ℃ | -0.09α(Hc) %/ ℃ |
BNP-10 | 5.8-6.2g/cm3 | 1.20μ r | -0.11α(Br) %/ ℃ | -0.11α(Hc) %/ ℃ |
BNP-11 | 5.8-6.2g/cm3 | 1.20μ r | -0.11α(Br) %/ ℃ | -0.11α(Hc) %/ ℃ |
BNP-12L | 5.8-6.2g/cm3 | 1.20μ r | -0.08α(Br) %/ ℃ | -0.26α(Hc) %/ ℃ |