稀土-铁Laves相化合物的结构与磁致伸缩

STRUCTURE AND MAGNETOSTRICTION OF RAREEARTHIRON LAVES PHASE COMPOUNDS

采用光学显微、Ｘ射线衍射、热磁分析和电阻应变仪技术研究了Ｒ（Ｆｅ１－ｘＧａｘ）１．８５合金的结构与磁致伸缩．这些合金的基体具有立方Ｌａｖｅｓ相结构．加入少量的Ｇａ使赝二元Ｌａｖｅｓ相化合物的均匀范围移向化学计量成分．增加Ｇａ的含量，晶格常数线性增大，而居里温度和室温磁致伸缩λｓ迅速降低．低磁场下（Ｈ＜４ｋＯｅ），ｘ＝０．

The structure and magnetstriction of RFe 1- x Ga x ) 1.85 alloys(R=Dy 0.65 Tb 0.25 Pr 0.1 ,0x0.2) have been investigated using optical microscopy,Xray diffraction,ac susceptibility and standard strain gauge techniques. It was found that the matrix of these alloys possesses Cubic Laves' strcuture. The addition latticeof gallium shifts the homogeneity range of the psueudobinary compound towards the stoichiometric composition. The lattice parameter imcreases linely,while the curie temperature and the room temperature magnetostriction λ s decrease rapidly with incresaing Ga content.The magnetostriction of the alloy with x=0.02 in low magnetic fields ( H <4 kOe) is superior to that of the other alloys.