Phases equilibrium study in quaternary iron-rich Fe-Al-Mn-C alloys

Abstract

High aluminium low manganese steels were elaborated in order to study the phase equilibrium in the range of 900-1 100°C. Two different quaternary alloys have been studied (Fe-9 to 10wt%Al-1.7wt%Mn0.2wt%C and Fe-9 to 10wt%AI-8wt%Mn-0.2wt%C). Equilibrium phase's nature was identified at four temperatures for two alloys. Equilibrium phase fraction and chemical compositions were determined at 900°C. Thanks to these equilibrium results, we tried to understand the non-equilibrium microstructure observed after different thermal histories (DTA cycles, isothermal treatment followed by quench, reception state) and identify DTA events in a coherent way. © 2007 ISIJ.