Equilibrium phase relations in the U–Zr–Fe ternary system

Abstract

Equilibrium phase relations in the U–Zr–Fe ternary system have been investigated experimentally at 853, 973 and 1073 K. The composition of each phase has been determined using the electron probe microanalysis. The differential thermal analysis has also been applied to check the phase relations and examine the stabilities of the ternary compounds. The compositions of the phases found near the sub-binary edges are consistent with the published binary phase diagrams. Three ternary compounds have been found and designated ε, λ and χ, the compositions of which are U–(33–50)Zr–33Fe, U–(21–25)Zr–6Fe and U–32Zr–50Fe (at.%), respectively. The single ε-phase melts at 1206 ± 5 K. The λ-phase decomposes to ε and γ at 999 ± 2 K. The χ-phase exists up to 1168 ± 10 K at the lowest. The equilibrium phase diagrams determined or estimated from the experimental results are consistent with the diagrams calculated using thermodynamic models.