| Summary: | <i>γ</i>-TiAl has been a hot topic of research for more than a few decades now, since it is a potential candidate for high temperature structural applications. In this paper, dispersion strengthening of <i>γ</i> based TiAl alloy, produced by means of centrifugal casting, has been performed to increase its mechanical properties beyond those of standard TiAl alloys. After a careful selection of the alloy composition based on the desired properties, several samples were produced by means of investment casting. This work focused on the effect of Al<sub>2</sub>O<sub>3</sub> nano- and micro-dispersoids on the mechanical properties of the considered TiAl alloy. Microstructural investigations were carried out to study both the alloy microstructure and the Al<sub>2</sub>O<sub>3</sub> dispersion homogeneity. Samples of the produced alloy were subjected to four-point bending tests at different temperatures for evaluating the effect of dispersed particles on mechanical properties. The results of this study were promising and showed that Al<sub>2</sub>O<sub>3</sub> dispersion determined an increase of the mechanical properties at high temperatures. The Young’s modulus was 30% higher than that of the reference alloy in the lower temperature range. Over the temperature range 800–950 °C the dispersion strengthening affected the yield stress by increasing its value of about 20% even at 800 °C. A detailed evaluation of fracture surfaces was carried out to investigate fracture mechanisms.
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