Vertical sections of Tb sub(0.15)Ho sub(0.85)Fe sub(y)-Tb sub(0.3)Dy sub(0.7)Fe sub(y) (y = 1.85, 1.9, 2.0) in Tb-Dy-Ho-Fe system

The x(Tb sub(0.15)Ho sub(0.85) Fe sub(y))+(1-x)(Tb sub(0.3)Dy sub(0.7)Fe sub(y)) (x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9; y = 1.85, 1.9, 2.0) samples were prepared by a vacuum arc furnace, and annealed at 1000 [degrees]C for 1 d and at 950 [degrees]C for a week. Three vertical sections of Tb sub(0.15)Ho sub(0.85)Fe sub(y)-Tb sub(0.3)Dy sub(0.7)Fe sub(y) (y=1.85, 1.9, 2.0) in the Tb-Dy-Ho-Fe system were determined using optical microscopy, scanning electron microscopy, energy dispersion X-ray spectroscopy, X-ray diffraction, and differential thermal analysis. These vertical sections consisted of two single-phase regions: L and (Tb,Dy,Ho)Fe sub(2); four two-phase regions: L+(Tb,Dy,Ho)Fe sub(3), L+(Tb,Dy,Ho)Fe sub(2), (Tb,Dy,Ho)Fe sub(2)+(Tb,Dy,Ho)Fe sub(3), and (Tb,Dy,Ho)Fe sub(2)+(Tb,Dy,Ho). The high Ho content of (Tb,Dy,Ho)Fe sub(v) alloys led to the elevation of the peritectic temperature of L+(Tb,Dy,Ho)Fe sub(3) arrow right (Tb,Dy,Ho)Fe sub(2). The region of (Tb,Dy,Ho)Fe sub(2) phase was shifted towards the side of rich-Ho with the Fe content increasing. It meant that the substitution of Ho for Dy or Tb had a marked effect on the solidification process of (Tb,Dy,Ho)Fe sub(2) compounds.