There is a huge gap between the magnetic properties of bonded magnets and sintered Neodymium magnets, therefore, high-abundant rare-earth permanent magnets and hot pressed magnet are regarded as the potential options to fill this gap. In fact, hot pressed magnets are another solution to manufacture anisotropic radially oriented ring magnets except conventional sintered type. Randomly oriented crystals go through preferential grain growth and rotation during continuously hot-working process, then results in the full-density nanocrystalline structure with superior magnetic performance in the radial direction.
Advantages of Hot Pressed Magnets
- Energy Products of the radial direction can achieve 240 ~ 360 kJ/m3.
- Ideal thermal stability, Max. Operating Temperature can reach 200 degrees Celsius.
- Ring magnet with small-sized or high L/D ratio is possible.
- Nanocrystalline structure and high density will provide excellent anti-corrosion performance for the hot-pressed magnets.
- Hot-pressed magnet also has flexible magnetization pattern which will improve motor performance.
Manufacturing Process of Hot Pressed Magnets
Magnetic Properties Chart of Hot Pressed Magnets
| Grade | Remanence
Br |
Coercivity
Hcb |
Intrinsic Coercivity
Hcj |
Max. Energy Product
(BH)max |
||||
| T | kGs | kA/m | kOe | kA/m | kOe | kJ/m3 | MGOe | |
| 50M | 1.40-1.45 | 14.0-14.5 | ≥1043 | ≥13.1 | ≥1114 | ≥14 | 374-406 | 47-51 |
| 45M | 1.33-1.37 | 13.3-13.7 | 954-1058 | 12.0-13.1 | ≥1273 | ≥16 | 318-366 | 40-46 |
| 42M | 1.29-1.32 | 12.9-13.2 | 939-1034 | 11.8-13.0 | ≥1273 | ≥16 | 302-342 | 38-43 |
| 48H | 1.35-1.40 | 13.5-14.0 | 1042-1114 | 13.1-13.6 | ≥1432 | ≥18 | 342-366 | 43-36 |
| 45H | 1.32-1.35 | 13.2-13.5 | 954-1042 | 12.5-13.1 | ≥1432 | ≥18 | 318-342 | 40-43 |
| 42H | 1.29-1.32 | 12.9-13.2 | 931-1010 | 12.2-13.1 | ≥1432 | ≥18 | 286-326 | 36-41 |
| 40H | 1.26-1.29 | 12.6-12.9 | 931-1010 | 11.7-12.7 | ≥1432 | ≥18 | 286-318 | 36-40 |
| 45SH | 1.32-1.35 | 13.2-13.5 | 954-1042 | 12.5-13.1 | ≥1592 | ≥20 | 318-342 | 41-44 |
| 42SH | 1.29-1.32 | 12.9-13.2 | 962-1042 | 12.2-13.1 | ≥1592 | ≥20 | 302-326 | 38-41 |
| 40SH | 1.26-1.29 | 12.6-12.9 | 939-1010 | 11.8-12.7 | ≥1592 | ≥20 | 286-318 | 36-40 |
| 38SH | 1.22-1.26 | 12.2-12.6 | 923-986 | 11.6-12.4 | ≥1592 | ≥20 | 278-310 | 35-39 |
| 35SH | 1.18-1.23 | 11.8-12.3 | 891-962 | 11.2-12.1 | ≥1592 | ≥20 | 246-286 | 31-36 |
| 38UH | 1.22-1.26 | 12.2-12.6 | 907-986 | 11.4-12.4 | ≥1989 | ≥25 | 278-318 | 35-40 |
| 35UH | 1.18-1.23 | 11.8-12.3 | 891-962 | 11.2-12.1 | ≥1989 | ≥25 | 246-286 | 31-36 |
- The above-mentioned data of magnetic properties and physical properties are given at room temperature.
- The max working temperature of magnet is changeable due to length-diameter ratio, coating thickness and other environment factors.