Experimental investigation of phase equilibria in the Ce-Fe-Ni system

Phase transformations in the Ce-Fe-Ni ternary system have been studied using DTA, X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). Liquidus and solidus projections and a Scheil diagram for solidification were constructed. A continuous solid solution between the Laves phase compounds, CeFe2 and CeNi2, with cubic MgCu2-type structures forms in this system at the solidus temperatures. A new binary compound Ce5Ni19 was found in the Ce-Ni system. The binary system-based phases, CeNi5, Ce5Ni19, Ce2Ni7 and CeNi3, have the widest homogeneity regions and dissolve at the solidus temperature up to 29.4, 23.4, 25.6 and 35.4 at.% Fe, respectively. The homogeneity regions of the remaining phases are smaller. No ternary compounds have been identified in this system. Seven three-phase fields in the solidus surface result from three transition type, two peritectic and two eutectic invariant four-phase equilibria. •A new binary compound Ce5Ni19 has been identified for the first time.•Liquidus and solidus projections and a Scheil diagram were constructed for the Ce-Fe-Ni system.•Appreciable solubilities of Fe were observed in the binary compounds.•No ternary compounds have been identified in this system.