Intrinsic and hard magnetic properties of Sm2(Fe1 − xAlx)17 nitrides

The intrinsic and hard magnetic properties of Sm 2 (Fe 1 − x Al x ) 17 nitrides were investigated. The Curie temperature and saturation magnetization decrease linearly with increasing Al concentration, as also does the anisotropy field at room temperature. The X-ray diffraction patterns have shown that all the samples exist in a nearly single phase with Th 2 Zn 17 -type structure for x up to 0.12. The lattice parameters increase with the substitution of Al for Fe atoms. The hard magnetic properties of the nitrides obtained indicate that the addition of Al has an unfavorable effect. The onset decomposition temperature of all nitrides derived from the thermomagnetic curves is around 750 K, implying that Al substitution could not improve the thermal stability of 2:17 nitrides.