First principle energies of binary and ternary phases of the Fe–Nb–Ni–Cr system

Abstract

We present first principles enthalpies of formation and lattice parameters of iron, nickel, chromium and niobium alloys. Some of these results have been partially used in a recent assessment of the Fe–Ni–Cr–Nb quaternary phase diagram. Emphasis has been put on the fcc (A1) and bcc (A2) unary structures, the X3Y -D022,-L12,-D03,-D0a,X2Y -C14(MgZn2),-C15(MgCu2) and -C36 (MgNi2) Laves and X7Y 6-D85 (μ) binary phases, and the X8Y 4Z18-D8b (σ) ternary phase. We employed the state of the art to compute their properties by means of the DFT (PBE functional and PAW pseudo potentials). A comparison with experimental and theoretical data is also provided.