Composite magnet introduction
Bonded magnet and Injection Molded are the main method to modified composite magnets. Bonded magnet is manufactured through the process of compression and bonding which offer higher magnetic characteristics but are limited to simpler geometries than Injection Molded materials. Using certain permanent magnet properties of bonded magnet, powder and binder mixed, according to a certain application or designing in different project.
Injection Molding magnet:
- Binder Types / Nylon / PPS / Polyamide(polymide).
- Temperature Range -40c – 180c
- Very Tight tolerances off tool ( 0.002 -0.003 Typical )
- Better mechanical strength
Compression Bonded magnet:
- Higher Magnetic Strength due to higher magnetic particle density.
- Epoxy Binder / Resistant to normal industrial solvents and automotive fluids
- Epoxy Coat after manufacturing to prevent oxidation
- Temperature Range -40c – 165c
- “Tight” tolerances off tool
- Good mechanical strength
Bonded magnet specification:
| Magnetic Characteristics | 1009 | 0813 | |
| Residual Induction (Br) |
(G) | 6800 | 6350 |
| (mT) | 680 | 635 | |
| Coercive Force (Hc) | (Oe) | 5800 | 5600 |
| (kA/m) | 460 | 440 | |
| Intrinsic Coercive Force Hcl | (kOe)Minimum | 9100 | 13900 |
| (kA/m) | 720 | 1100 | |
| Maximum Energy Product BHmax | (MGOe) | 10 | 8.8 |
| (kJ/m) | 79 | 70 | |
| Magnetic Characteristics | 1009 | 0813 | |
| Density | (lbs/in) | 0.213 | 0.213 |
| (g/cm) | 5.9 | 5.9 | |
| Curie Temperature | °F Nominal | 680 | 878 |
| °C Nominal | 360 | 470 | |
| Maximum Operating Temperature | °F | 302 | 302 |
| °C | 150 | 150 | |
Bonded magnet advantage:
- Materials are isotropic and can be magnetized in any direction
- Wide range of existing tool sizes are available in rings, discs and rectangles
- Existed Multi-pole magnetizing fixtures for quick prototyping
- Easily machined
- Existing Multi-pole rings simplify assembly verse arc segment