Effect of Al2O3 concentration on the mechanical properties of γ-TiAl-based alloys at high temperature

γ-TiAl-based alloys have been studied for many years because they are interesting candidates for the production of mechanical components working at high temperature. Increasing toughness and mechanical resistance of these alloys is crucial for boosting their application. In this paper, after having selected its composition, the alloy was produced by centrifugal casting and was reinforced by using Al2O3 nano-and micro-dispersoids. Four-point bending tests performed at high temperatures highlighted that the addition of 2% of Al2O3 is more effective than 3% of Al2O3 in increasing the alloy mechanical properties over the 800-900°C temperature range. The study revealed that this can be explained considering that a lower percentage of dispersoids allows to improve the oxide dispersion and to decrease the dispersed particle size.