Phase equilibria in the Y–Hf–Fe system and hydrogen sorption properties of alloys

Abstract

We have investigated the interaction of the components in the ternary Y–Hf–Fe system by the methods of X-ray phase analysis, X-ray diffraction analysis, and energy-dispersive X-ray microanalysis and constructed an isothermal section of the constitution diagram at 800°С. The extents of substitutional solid solutions based on the binary compounds YFe 3 (Y1− xHfxFe 3, 0 ≤ x ≤ 0.2) and Y2Fe17 (Y2− xHfxFe17 , 0 ≤ x ≤ 1.3) have been established . The crystal structure of the compound Hf0.93Fe2 (the MgZn 2 structure type, space group P6 3 /mmc , Pearson symbol hP12 , a = 0.49440(7) nm, and c = 0.8066(2) nm) has been refined for the first time by the single-crystal method. We have investigated the hydrogen sorption properties of Y1− xHfxFe2 alloys with the structure of the C15 Laves phase, Y1− xHfxFe 3 alloys with the PuNi3 -type structure, and (Hf1− xYx )2 Fe alloys with the Ti2Ni -type struc