| Autor: |
Marian Grigoras, Mihaela Lostun, Marieta Porcescu, George Stoian, Gabriel Ababei, Nicoleta Lupu |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Crystals, Vol 13, Iss 11, p 1578 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2073-4352 |
| DOI: |
10.3390/cryst13111578 |
| Popis: |
The iron nitride materials, especially α″-Fe16N2, are considered one of the most promising candidates for future rare-earth-free magnets. However, the mass production of α″-Fe16N2 powders as a raw material for permanent magnets is still challenging. In this work, starting from iron lumps as a raw material, we have managed to prepare the α″-Fe16N2 powders via the gas atomization method, followed by subsequent nitriding in an ammonia–hydrogen gas mixture stream. The particle size was controlled by changing the gas atomization preparation conditions. X-ray diffractograms (XRD) analyses show that the prepared powders are composed of α″-Fe16N2 and α-Fe phases. The α″-Fe16N2 volume ratio increases with decreasing powder size and increasing nitriding time, reaching a maximum of 57% α″-Fe16N2 phase in powders with size below 32 ± 3 μm after 96 h nitridation. The saturation magnetization reaches the value of 237 emu/g and a reasonable coercivity value of 884 Oe. Compared to the saturation magnetization values of α-Fe powders, the α″-Fe16N2 powders prepared through our proposed approach show an increase of up to 10% in saturation and demonstrate the possibility of mass production of α″-Fe16N2 powders as precursors of permanent magnets without rare earths. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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