| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Magnetism and Magnetic Materials
|
| Presentation Title |
Protecting ultrafine grained Dy-free Nd-Fe-B sintered magnets with varied passivation techniques |
| Author(s) |
Belle Finney, Baozhi Cui, Wei Tang, Matthew J. Kramer, Iver E. Anderson |
| On-Site Speaker (Planned) |
Belle Finney |
| Abstract Scope |
The impressive ambient strength of Nd-Fe-B permanent magnets has been well-known since their development in the 1980s. These rare-earth permanent magnets have been widely used in the last few years. However, “neo” magnets without significant Dy additions have a wide variety of applications but are not used in many high-temperature (>150ºC) applications due to the inability to maintain sufficient coercivity. To avoid the use of heavy RE (Dy or Tb) additions, Nd-Fe-B magnets with ultrafine (<2-3 µm) grain size have been shown by Hono to improve ambient and high-temperature magnetic properties. However, the superfine (1-2 µm) powder feedstock needed to make these magnets has enormous surface area that readily oxidizes, decreasing magnetic saturation. To combat this oxidation, passivation of these powders during/after milling is crucial to protect the magnetic properties of the final Nd-Fe-B sintered magnet. Support from U.S. Department of Energy-EERE-Vehicle Technologies Office through Ames National Laboratory contract DE-AC02-07CH11358. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Magnetic Materials, Powder Materials, Sustainability |