Microstructure and high temperature mechanical properties of Zr-alloyed Fe3Al-type aluminides: The effect of carbon

The effect of the additives Zr and C on the phase composition and high temperature (H.T.) mechanical properties of Fe3Al-type alloys is investigated. The presence of phases is related to the ratio of zirconium and carbon in the alloy. The presence of Laves phase λ1 (Fe,Al)2Zr particles is governed by the relationships seen in the ternary phase diagram for Fe–Al–Zr, while the appearance of ZrC carbide particles is due to the affinity of Zr for C. The presence of tiny metastable phase particles, identified as (Fe1−xAlx)3Zr and Fe2Zr, affects the H.T. tensile and creep properties of the alloys.

► Tensile and creep tests on a series of Fe3Al-based alloys with additions of zirconium and carbon.
► Creep exponents and activation energies are given.
► Laves phase λ1 and ZrC particles are found primarily along grain boundaries.
► Small particles of metastable phases (Fe1−xAlx)3Zr and Fe2Zr interact with dislocations.