The compound Sm0.98Fe9.02-xGaxNδ(x=0, 0.25, 0.5, 0.75, 1) were prepared by melt-spun method and subsequent annealing and nitriding. The Rietveld analysis showed that the lattice expansion played an important role i...The compound Sm0.98Fe9.02-xGaxNδ(x=0, 0.25, 0.5, 0.75, 1) were prepared by melt-spun method and subsequent annealing and nitriding. The Rietveld analysis showed that the lattice expansion played an important role in improving the Curie temperature. An obvious development of the Curie temperature was obtained with the increased Ga content from x=0-1 (ΔTc=90 ℃). The optimum coercivity of nitrides was obtained at x=0.25 with the value Hcj=652 kA/m (8.15 kOe) after annealing, which corresponded to a reasonable distribution of grain sizes of both TbCu7-type SmFe9Nδandα-Fe. However, an excess of Ga doping might lead to an ab-normal growth of α-Fe, which in turn deteriorated the magnetic properties. It was concluded that a moderate Ga content was very ef-fective in raising the coercivity and Curie temperament in the TbCu7-type Sm-Fe-N.展开更多
基金supported by International Science and Technology Cooperation Project(2010 DFB53520)the National High Technology Research and Development Program of China(2011AA03A402)
文摘The compound Sm0.98Fe9.02-xGaxNδ(x=0, 0.25, 0.5, 0.75, 1) were prepared by melt-spun method and subsequent annealing and nitriding. The Rietveld analysis showed that the lattice expansion played an important role in improving the Curie temperature. An obvious development of the Curie temperature was obtained with the increased Ga content from x=0-1 (ΔTc=90 ℃). The optimum coercivity of nitrides was obtained at x=0.25 with the value Hcj=652 kA/m (8.15 kOe) after annealing, which corresponded to a reasonable distribution of grain sizes of both TbCu7-type SmFe9Nδandα-Fe. However, an excess of Ga doping might lead to an ab-normal growth of α-Fe, which in turn deteriorated the magnetic properties. It was concluded that a moderate Ga content was very ef-fective in raising the coercivity and Curie temperament in the TbCu7-type Sm-Fe-N.