Nd2(Fe,Si)17合金的结构与磁性

本文对Nd-Fe-Si三元系富铁区域相的结构和磁性进行了研究。结果表明,Nd-Fe-Si三元系富铁区域(Fe>40at％),除出现NdFe₂Si₂三元金属间化合物外(Si>20at％),同时只出现Nd₂(Fe,Si)₁₇赝二元金属间化合物,其中Si取代9d位的Fe原子,而不能形成类似于Nd₂Fe₁₄B的三元金属间化合物,Si取代Nd₂Fe₁₇中的9d位Fe原子后,使晶胞体积缩小;使饱和磁化强度减小;同时使Fe次晶格的铁磁相互作用增强,导致居里温度增高;还使得Fe次晶格的易面各向异性减弱,造成室温下各向异性场减小。关键词：

STRUCTURAL AND MAGNETIC PROPERTIES OF Nd2(Fe,Si)17 ALLOYS

In this paper, structural and magnetic studies are carried out on the alloys of the iron-rich Nd-Fe-B ternary system. The results show that for the iron-rich (Fe>40 at%) alloys ternary compound Nd₂Fe₂Si₂ is formed (Si>20%) as well as pseudobinary compound Nd₂(Fe, Si)₁₇, in which Si atoms are substituted for the iron atoms on 9d-sites instead of forming new ternary compound as that of Nd₂Fe₁₄B. Upon substitution of Si for Fe, both cell volume and magnetization of the Nd₂(Fe,Si)₁₇ alloys decrease, but Curie temperature T_c increases due to an enhancement of the ferromagnetic interaction in the Fe sublattice. The room temperature anisotropy fields decrease with increasing Si eon-tent as a result of reduction of the plane anisotropy in the Fe sublattice.