Generally speaking, the bonded NdFeB magnet is produced by molding compression of the compound NdFeB alloy powder with epoxy resin, also it can be made by injection or extrusion from NdFeB alloy powder mixed with plastic. It has high production efficiency, suitable for mass production.The bonded NdFeB magnet is mainly used for all kinds of micro–miniature motors, such as spindle motor ( HDD, CD-ROM & DVD ), stepping motor, synchronous motor, DC motor and brushless DC motor. It can replace sintered NdFeB magnet and ferrite, making motor assembling simpler and more reliable, reducing costs and improving efficiency.
1. Higher Magnet Property: the magnet property of bonded NdFeB magnet is between that of sintered NdFeB and ferrite, and with good consistency and stability.
2. Large Freeness of Product Shapes and High Precision of Dimension: the magnet shape and dimension are decided by the tooling, like ring, segment, block, etc., without further sintering and mechanical machining processes.
3. Good Corrosion Resistance: after electrodeposited or through other special treatments, it can be used under normal or unfavorable environment conditions for a long time.
4. Diverse magnetization: Multi-pole magnetization and screw angle magnetization are available, and the field distribution could be square, sinusoid and so on.
| Grade | GPM-2 | GPM-4 | GPM-6 | GPM-8 | GPM-8L | GPM-8H | GPM-8SR |
| Br (mT) Residual Induction (Kgs) | 300-400 (3.0-4.0) | 400-500 (4.0-5.0) | 500-600 (5.0-6.0) | 600-680 (6.0-6.8) | 600-680 (6.0-6.8) | 600-660 (6.0-6.6) | 620-680 (6.2-6.8) |
| Hcb (KA/m) Coercive Force (KOe) | 240-320 (3.0-4.0) | 240-320 (3.0-4.0) | 320-400 (4.0-5.0) | 360-440 (4.5-5.5) | 400-480 (5.0-6.0) | 400-480 (5.0-6.0) | 400-480 (5.0-6.0) |
| Hcj (KA/m) Intrinsic Coercive Force (KOe) | 480-640 (6.0-8.0) | 560-720 (7.0-9.0) | 560-720 (7.0-9.0) | 640-800 (8.0-10.0) | 640-800 (8.0-10.0) | 1040-1360 (13.0-17.0) | 800-1120 (10.0-14.0) |
| Max. Energy Product (MGOe) (BH)max (KJ/m) | 24-32 (3.0-4.0) | 32-48 (4.0-6.0) | 48-60 (6.0-7.5) | 60-72 (7.5-9.0) | 64-72 (8.0-9.0) | 64-72 (8.0-9.0) | 68-76 (8.5-9.5) |
| Permeability (μH/M) μr/Recoil | 1.2 | 1.2 | 1.2 | 1.2 | 1.2 | 1.2 | 1.2 |
| Temperature Coefficient of B (%/℃) | -0.11 | -0.11 | -0.11 | -0.11 | -0.11 | -0.10 | -0.10 |
| Tc (℃) Curie Temperature | 300 | 300 | 300 | 300 | 350 | 350 | 350 |
| Max.Operating Temperature (℃) | 160 | 160 | 160 | 160 | 160 | 180 | 180 |
| Saturation (KA/m) Magnetizing Force (KOe) | >1600 >20 | >1600 >20 | >1600 >20 | >1600 >20 | >1600 >20 | >2400 >30 | >2000 >25 |
| Density ρ (g/cm3) | 4.5～5.0 | 5.0～5.5 | 5.5～5.8 | 5.8～6.0 | 5.8～6.1 | 5.8～6.1 | 5.8～6.1 |
| HRB Hardness | 40～45 | 40～45 | 40～45 | 35～38 | 35～38 | 35～38 | 35～38 |
| Grade | GPM-10 | GPM-10H | GPM-12 | GPM-12D | GPM-12H | GPM-12L | GPM-13L |
| Br (mT) Residual Induction (Kgs) | 680-730 (6.8-7.3) | 700-750 (7.0-7.5) | 720-770 (7.2-7.7) | 720-770 (7.2-7.7) | 740-800 (7.4-8.0) | 760-810 (7.6-8.1) | 780-830 (7.8-8.3) |
| Hcb (KA/m) Coercive Force (KOe) | 400-480 (5.0-6.0) | 440-520 (5.5-6.5) | 440-520 (5.5-6.5) | 440-520 (5.5-6.5) | 440-520 (5.5-6.5) | 400-480 (5.0-6.0) | 400-480 (5.0-6.0) |
| Hcj (KA/m) Intrinsic Coercive Force (KOe) | 640-800 (8.0-10.0) | 640-800 (8.0-10.0) | 720-800 (9.0-10.0) | 720-880 (9.0-11.0) | 760-880 (9.5-11.0) | 480-640 (6.0-8.0) | 480-640 (6.0-8.0) |
| Max. Energy Product (MGOe) (BH)max (KJ/m) | 76-84 (9.5-10.5) | 80-88 (10.0-11.0) | 88-96 (11.0-12.0) | 88-96 (11.0-12.0) | 88-96 (11.0-12.0) | 88-96 (11.0-12.0) | 88-104 (11.0-13.0) |
| Permeability (μH/M) μr/Recoil | 1.2 | 1.2 | 1.2 | 1.2 | 1.2 | 1.2 | 1.2 |
| Temperature Coefficient of B (%/℃) | -0.10 | -0.10 | -0.10 | -0.10 | -0.10 | -0.12 | -0.12 |
| Tc (℃) Curie Temperature | 350 | 350 | 350 | 350 | 350 | 320 | 320 |
| Max.Operating Temperature (℃) | 160 | 160 | 160 | 160 | 160 | 150 | 150 |
| Saturation (KA/m) Magnetizing Force (KOe) | >1600 >20 | >1600 >20 | >1600 >20 | >1600 >20 | >1600 >20 | >1600 >20 | >1600 >20 |
| Density ρ (g/cm3) | 5.8～6.1 | 6.0～6.3 | 6.0～6.3 | 6.0～6.3 | 6.1～6.4 | 6.0～6.3 | 6.1～6.4 |
| HRB Hardness | 35～38 | 35～38 | 35～38 | 35～38 | 35～38 | 35～38 | 35～38 |
