Rare-Earth Lean Hard Magnet Compound NdFe12N

Among various ThMn12-type rare-earth iron compounds, NdFe11TiN has been known for its large magnetization and high anisotropy field, although their values are smaller than those of Nd2Fe14B and Sm2Fe17N3. Recent first-principles calculations predicted that NdFe12N has a substantially larger magnetization than NdFe11TiN with a comparable anisotropy field. To validate this prediction, the NdFe12N (x) phase was successfully synthesized by nitriding the NdFe12 film that was grown on a W underlayer on a MgO(001) substrate. The NdFe12N (x) phase was found to have a saturation magnetization, anisotropy field, and Curie temperature superior to those of Nd2Fe14B.