Compare permanent magnet families by energy product, temperature, corrosion behavior, cost and best-fit applications.
| Material | Energy Product | Temperature Capability | Corrosion Behavior | Relative Energy Density | Typical Applications |
|---|---|---|---|---|---|
| NdFeB | ~33–57 MGOe | 80–230°C class by grade | Requires protection in many environments | Very high | EV motors, robotics, compact high-flux systems |
| SmCo | ~8–35 MGOe | 250–350°C class | Excellent intrinsic resistance | High | High-temperature motors, sensors, harsh environments |
| Ferrite | ~0.8–5.3 MGOe | ~250°C reference | Excellent | Low | High-volume motors, speakers, separators |
| AlNiCo | ~1.5–9 MGOe | 450–525°C class | Good | Medium | Precision instruments, meters, sensors |
| Flexible | ~0.5–1.4 MGOe | 80–120°C class | Binder-dependent | Low | Signage, gaskets, converted sheets/strips |
Start with NdFeB when package size, torque density or field strength per unit volume dominates.
SmCo is usually the first material to review for demanding high-temperature circuits that still need strong coercivity.
Ferrite is the workhorse for motors, speakers and holding systems where package volume is available.
AlNiCo remains important for instruments and sensors where field stability over temperature is the deciding criterion.
Flexible bonded ferrite is selected when sheet, strip, die-cut, printing or conformability is more important than energy density.
Send the application conditions instead of guessing a material. We can compare candidate materials against temperature, geometry, air gap and cost.
| Input | Why it matters |
|---|---|
| Operating temperature / duty cycle | Controls coercivity class, irreversible loss and material family choice |
| Required field / flux / torque | Defines energy and magnetic-circuit target |
| Geometry & air gap | Changes permeance coefficient and working point |
| Environment | Drives coating, corrosion strategy and material family |
| Magnetization direction / pole count | Affects tooling, manufacturing route and field distribution |
| Tolerance / runout / assembly interface | Impacts grinding, fixture strategy and cost |
| Annual volume | Changes tooling and process economics |
| Compliance / export constraints | May affect rare-earth material route and documentation |
