A new structure of Nd1+εFe4BB4 phase in NdFeB magnet
نویسنده
چکیده
Sintered NdFeB magnets are relatively complex multiphase systems containing Nd2Fe14B matrix and about 15% of other intermetallics such as Nd1+εFe4BB4, Nd-oxides (Nd-rich phase), etc. Boron rich Nd1+εFe4B4 B forms in irregularly distributed heavily faulted grains of roughly the same size as those of the Nd2Fe14B phase [1]. The Curie temperature of this phase is 13K and, therefore, it is not ferromagnetic at room temperature and is deleterious to the magnetic properties of the magnets.
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