Experimental investigation of the Zr corner of the ternary Zr–Nb–Fe phase diagram

Abstract Intermediate phases in the Zr-rich region of the Zr–Nb–Fe system have been investigated by X-ray diffraction, optical and electron microscopy and electron microprobe analysis. The chemical composition ranges covered by the alloys studied here are: (41–97) at.% Zr, (32–0.9) at.% Nb and (0.6–38) at.% Fe. The phases found in this region were: the solid solutions α-Zr and β-Zr, the intermetallic Zr3Fe with less than 0.2 at.% Nb in solution, two new ternary intermetallic compounds (Zr+Nb)2Fe `λ1' with a cubic Ti2Ni-type structure in the composition range (2.4–13) at.% Nb and (31–33) at.% Fe, and (Fe+Nb)2Zr `λ2' indexed as hexagonal Laves phase MgZn2 type (C14) with a wide range of compositions close to (35–37) at.% Zr, (12–31) at.% Nb and (32–53) at.% Fe.