Scanning electron microscopy and transmission electron microscopy study of hot‐deformed γ‐TiAl‐based alloy microstructure

Abstract

SummaryThe aim of this work was to assess the changes in the microstructure of hot-deformed specimens made of alloys containing 46-50 at.% Al, 2 at.% Cr and 2 at.% Nb (and alloying additions such as carbon and boron) with the aid of scanning electron microscopy and transmission electron microscopy techniques. After homogenization and heat treatment performed in order to make diverse lamellae thickness, the specimens were compressed at 1000 °C. Transmission electron microscopy examinations of specimens after the compression test revealed the presence of heavily deformed areas with a high density of dislocation. Deformation twins were also observed. Dynamically recrystallized grains were revealed. For alloys no. 2 and no. 3, the recovery and recrystallization processes were more extensive than for alloy no. 1.

An in-situ high-energy X-ray diffraction study on the hot-deformation behavior of a β-phase containing TiAl alloy

“…Dynamic recovery occurs less readily due to the small SFE of γ (60-90 mJ/m 2 [46]). Chraponski et al [55] investigated a γ-TiAl based alloy which was hot-worked at 1000 °C by means of transmission electron microscopy and concluded that recrystallization as well as recovery occur in the γ-phase which is in excellent agreement with the present study. Additionally, this publication [55] points out that there is a significant degree of deformation inhomogeneity which is also confirmed by the current results.…”