氮化Y_2Fe_(17)和Dy_2Fe_(17)C合金的结构和磁性研究

Structure and Magnetic Properties of Y_2Fe_(17), Dy_2Fe_(17)C and Their Nitrides

本文用磁测量和穆斯堡尔方法研究了Y_2Fe_(17)和Dy_2Fe_(17)C合金及氮化后的结构和磁性。Y_2Fe_(17)和Y_2Fe_(17)N_ε(ε<3)具有六方结构,Dy_2Fe_(17)C和Dy_2Fe_(17)CN_ε为菱形结构。Y_2Fe_(17)氮化后的居里温度增加363K,Dy_2Fe_(17)C氮化后的居里温度增加201K。氮化后的合金中铁原子的平均磁矩和超精细场显著增加;同质异能移位略有增加。本文还探讨了氮化后合金磁性改善的原因。

The magnetic and crystallographic characteristica of Y_2Fe_(17), Dy_2Fe_(17)C and their nitrides have been studied. After introducing interstitial nitrogen atoms, the original Th_2Zn_(17) and Th_2Ni_(17) structures can be retained, but the lattice constants (a,c) are expanded; the hyperfine field and the average moment of iron atom are raised remarkably, and the isomeric shift is raised slightly. The curie temperatures of nitrides are increased by about 363K of Y_2Fe_(17) and 201K of Dy_2Fe_(17)C. The improvement mechanism of nitrogen atom on the intrinsic magnetic properties of Y_2Fe_(17) and Dy_2Fe_(17)C was discussed