Supply Chain > Motor Magnet Manufacturing
Magnet Manufacturing for Motors
Permanent magnet manufacturing is the conversion of NdFeB alloy into finished magnets used in electric motors, generators, and actuators. For EV traction motors and high-performance industrial drives, sintered NdFeB magnets dominate due to their unmatched power density, efficiency, and compact form factor.
Why permanent magnets matter
Permanent magnets enable motors with higher torque density, higher efficiency, and smaller size compared to wound-field alternatives. These attributes are central to electric vehicles, robotics, and advanced industrial automation.
- Higher torque density reduces motor mass and size
- Higher efficiency improves vehicle range and system efficiency
- Compact motors enable tighter packaging and higher system integration
Magnet manufacturing flow
- NdFeB alloy preparation and casting
- Hydrogen decrepitation and jet milling into fine powder
- Magnetic alignment and pressing
- Sintering to form dense magnet structure
- Machining and shaping to final geometry
- Grain boundary diffusion (optional) using Dy or Tb
- Surface coating for corrosion protection
Sintered vs bonded NdFeB magnets
- Sintered NdFeB magnets — highest performance; dominant in EV traction motors
- Bonded NdFeB magnets — lower performance; used in sensors and low-power applications
Temperature and dysprosium tradeoffs
Motor operating temperature strongly influences magnet formulation. Higher temperature capability typically requires heavy rare earths such as dysprosium or terbium, which improve coercivity but increase cost and supply risk.
- Grain-boundary diffusion minimizes heavy rare earth usage
- Motor cooling and design choices can reduce heavy rare earth dependency
- System-level optimization often substitutes engineering for materials intensity
Manufacturing constraints
- Oxygen control during alloying and powder handling
- Powder handling safety and yield management
- Precision sintering and alignment control
- Long qualification cycles tied to specific motor designs
Prmanent magnet manufacturing plants
The table below lists representative facilities engaged in NdFeB permanent magnet manufacturing. These plants convert NdFeB alloy into finished magnets through powder processing, sintering, diffusion, and finishing. Status reflects publicly disclosed operating or development position.
| Company / Operator | Facility | Location | Magnet type | Status | Notes |
|---|---|---|---|---|---|
| MP Materials | Fort Worth Magnetics Plant | Fort Worth, Texas, United States | Sintered NdFeB | ||
| JL MAG Rare-Earth | NdFeB Magnet Manufacturing Bases (multiple) | China (multiple) | Sintered NdFeB | ||
| Zhong Ke San Huan | NdFeB Magnet Production Facilities | China (multiple) | Sintered NdFeB | ||
| TDK | NdFeB Magnet Manufacturing Plants | Japan / Asia | Sintered NdFeB | ||
| Proterial (formerly Hitachi Metals) | NdFeB Magnet Manufacturing Sites | Japan / Global | Sintered NdFeB | ||
| VACUUMSCHMELZE (VAC) | Permanent Magnet Plants | Germany / Europe | Sintered NdFeB | ||
| Shin-Etsu Chemical | NdFeB Magnet Manufacturing | Japan | Sintered NdFeB |
Supply-chain role
Permanent magnet manufacturing is a capital-intensive, process-sensitive step that cannot be rapidly scaled without experience and qualified production lines. Even with sufficient rare earth refining, magnet output can remain constrained by alloy preparation, sintering capacity, and quality control.
As electrification scales, permanent magnet manufacturing sits alongside battery materials and power electronics as a foundational industrial capability rather than a commodity process.
