Phase equilibria in the Fe-Nb-Zr system at 1,200 °C were determined by X-ray diffraction (XRD) and scanning electron microscope (SEM) coupled with energydispersive X-ray spectroscopy (EDS) techniques. Extensive NbFe2 domain was proposed in the current work. This compound existed in the composition range from 35 at% to 73 at% Fe, 12 at% to 32 at% Nb, and 0 to 32 at% Zr. In the present work, four three-phase regions (1)-(Nb,Zr)+NbFe2+NbFe2, (2)-(Nb,Zr)+NbFe2+Liquid, (3)NbFe2+Liquid+ZrFe2, and(4)ZrFe2+Fe+NbFe2, were established.
