The forging capabilities of two high-strength Fe3Al-based alloys have been evaluated. Based on these results one alloy has been used for forging steam turbine blades. Blades of about 600 mm length were successfully forged by a standard procedure otherwise employed for forging of 9-12 wt.% Cr steels. The forged steam turbine blades showed very good form filling, no pores and smooth surfaces. The blades were finished by cutting and grinding by standard procedures. The microstructure consists out of a Fe3Al matrix with additional Laves phase which predominantly precipitated on grain boundaries. The large Fe3Al grains in the cast precursors did only partially recrystallise during forging. This may be partially due to pinning of the grain boundaries by Laves phase precipitates. Cracks may form at those grain boundaries which are decorated with these brittle precipitates.
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