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'.