Assessment of the Al-Fe-Ti system

The Al-Fe-Ti system has been assessed and the limiting binary systems are shortly reviewed. Based on a thorough review of the literature, isotherms at 800, 900, and 1000 degrees C have been re-evaluated and a provisional isotherm at 1200 degrees C is presented for the first time. The effect of alloying the binary phases with the third component is reviewed with regard to the ternary homogeneity ranges, crystallography, order/disorder transformations. and site occupancies. Of the variously reported ternary compounds only the existence of Al2FeTi (tau(2)) and Al8FeTi3 (tau(3)) is confirmed. The occurrence of the phases tau(2)*, tau'(2), and of a new stacking variant of TiAl is still under discussion, while the existence of the phases Fe2AlTi (tau(1)) and Fe25Al69Ti6 (X) is ruled out. The presented reaction scheme corroborates the isothermal sections and also a representation of the liquidus surface is given. Magnetic, electrical, thermochemical, atomistic and diffusion data for Al-Fe-Ti alloys are summarised and an overview about studies on modelling of phase equilibria and phase transformations is given. (C) 2006 Elsevier Ltd. All rights reserved.