Characterization of the Fe-rich corner of Al–Fe–Si–Ti

The quaternary system Al–Fe–Si–Ti was studied in the iron-rich corner for sections at 50, 60 and 70 at.% Fe at 900 °C. Isothermal phase equilibria were investigated by a combination of optical microscopy, X-ray powder diffraction (XRD) followed by Rietveld refinement and Electron Probe Microanalysis (EPMA). Phase boundaries of the phases, in particular of the Laves phase (Fe2Ti) and of the extended phase field of A2/B2/D03, were investigated. Selected samples containing the Laves phase and the B2 phase were characterized by microhardness measurements at different compositions throughout the quaternary homogeneity range of the phases.