Concepts derived from phase diagram studies for the strengthening of Fe–Al-based alloys

Fe–Al-based alloys, i.e. alloys which contain either disordered A2 α-(Fe,Al), B2-ordered FeAl or D03-ordered Fe3Al as majority phase, have a considerable potential for developing materials for structural applications, but insufficient strength and creep resistance have been identified as obstacles for the use of Fe–Al-based alloys at high temperatures. At the ‘Discussion Meeting on the Development of Innovative Iron Aluminium Alloys’ held at the Max-Planck-Institut für Eisenforschung GmbH, Düsseldorf on March, 9th 2004 a couple of presentations were made with emphasis on improving these properties at high temperatures. In the current article those strengthening mechanisms which are provided by the phase diagram—solid-solution hardening, strengthening by precipitates, or ordering—are reviewed. Besides results obtained for the binary Fe–Al system special emphasis is put forward to those ternary systems for which results have been presented at the ‘Discussion Meeting’.