| About this Abstract |
| Meeting |
2024 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Magnetism and Magnetic Materials
|
| Presentation Title |
Protecting Magnetic Properties of Ultrafine-grained Dy-free Nd-Fe-B Sintered Magnets |
| Author(s) |
Belle Finney, Wei Tang, Jun Cui, Matthew Kramer, Iver E Anderson |
| On-Site Speaker (Planned) |
Belle Finney |
| Abstract Scope |
Nd-Fe-B permanent magnets are well known for their ambient magnetic strength. However, the addition of Dy is needed for thermal stability that allows operation at a temperature of 150-180°C in drive motors, and this heavy rare earth is not sustainable due to highly constrained supplies, i.e., an alternative must be found. Fortunately, ultrafine (<~3μm) grain size in Dy-free Nd-Fe-B improves ambient and high-temperature magnetic properties, but this is only a lab-scale demonstration. Using gas atomization with energetic jet milling, optimal ultrafine grain size by a scalable process might also be possible. To avoid oxidation in these ultrafine powders, a reaction gas can be introduced to the atmospheres of the atomizer and the mill to synthetically passivate/protect these feedstock powders and preserve the powerful magnetic phase. These ultrafine single-crystal particles could be ideal for alignment and fully dense Dy-free sintered magnets. Funding from DOE-EERE-VTO through Ames Lab contract No. DE-AC02-07CH11358. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Magnetic Materials, Powder Materials, Magnesium |