The effect of lamellar separation on the properties of a Ti-46Al-2Nb-2Cr intermetallic alloy

The relationships between the γ and α2 lamellae apparent separation and hardnesses as well as the peak flow stresses estimated in hot compression tests obtained for specimens made of Ti-46Al-2Nb-2Cr alloy are presented. The lamellae separations were estimated using image analysis on the microstructure of the specimens. The procedure employing a fast Fourier transformation of secondary electron microstructural images for fully automatic lamellae separation measurements is described. It was found that the effect of the apparent lamellae separations of γ and α2 on the peak flow stress is significant. For the microstructure with thick lamellae of γ and α2 phases, the peak flow stress decreases. The hardness of the specimens decreases with an increase of the lamellae apparent separation as well.