The stability of alloying additions in Zirconium

The interactions of Cr, Fe, Nb, Ni, Sn, V and Y with Zr are simulated using density functional theory. Thermodynamic stabilities of various different Zr based intermetallic compounds, including multiple Laves phase structures and solutions of alloying additions in both alpha and beta-Zr were investigated. The thermodynamic driving forces in this system can be correlated with trends in atomic radii and the relative electronegativities of the different species. Formation energies of Fe, Ni and Sn based intermetallic compounds were found to be negative, and the Zr2Fe and Zr2Ni intermetallics were metastable. Most elements displayed negative energies of solution in beta-Zr but positive energies in the alpha-phase, with the exception of Sn (which was negative for both) and Y (which was positive for both). Solutions formed from intermetallics showed a similar trend. (C) 2013 Elsevier B.V. All rights reserved.