非晶态合金FeTmB的磁矩和居里温度

本文系统地报道单辊液淬方法制备FeTmB(Tm=Ti,V,Cr,Mn,Zr,Nb,Mo,Ta,W)非晶态合金的磁性,讨论了3d,4d,5d元素的加入对非晶态FeB合金的磁矩和居里温度的影响。实验结果表明在非晶态FeTmB合金系中Fe原子磁矩都在2.0μ_B左右。Tm原子在非晶态Fe基合金中比在相应的晶态合金中显示更强的局域特性。Tm原子的磁矩与元素的外层电子数有关,IVB(Ti),VB(V),VIB(Cr),VIIB(Mn)族原子的磁矩分别约为4,5,4,3μ_B,Tm的磁矩与铁原子磁矩反平行耦合。合金磁矩随Tm含量的变化率dμ/dx与混合模型的计算值相符合。用虚拟束缚态讨论,得到IVB(Ti),VB(V)族元素的虚拟束缚态在费密面以上,VIB(Cr),VIIB(Mn)族元素的虚拟束缚态与费密面交迭。 关键词：

MAGNETIC MOMENT AND CURIE TEMPERATURE OF AMORPHOUS FeTmB ALLOYS

Systematic experimental results for atomic magnetic moment and Curie temperature for amorphous alloys FeTmB(Tm=Ti, V, Cr, Mn, Zr, Nb, Mo, Ta, W) prepared by the drum spinning techniqul are reported. The average magnetic moment for each Ye atom is about 2.0 μ_B in all amorphous FeTmB alloys. The localized characteristics for Tm atom in the amorphous state is much outstanding than in the crystalline state. The average magnetic moment for each IVB(Ti), VB(V), VIB(Cr), VIIB(Mn) atom related with the number of outer electrons per atom is about 4, 5, 4, 3 μ_B, respectively, and is antiferromagnetic coupling with the Fe magnetic moment. The experimental data of the magnetic moment change rate dμ/dx is in good agreement with the calculated value using a mixed model. According to Friedel's VBS model the delectron states of IVB(Ti), VB(V) elements are completely above the Fermi level E_F, but for the VIB(Cr), VIIB(Mn) elements they cross the Fermi level E_F.