Effect of titanium addition on the oxidation resistance of Fe–13Cr-5Al-0.3Ti alloy in air between 700 °C–1100 °C

Cyclic oxidation tests were carried out on a Fe–13Cr–5Al–0.3Ti alloy over a temperature range of 700 °C–1100 °C in air. The composition and structure of the oxide layer were characterized by SEM and XRD, and the influence of temperature and Ti on the oxidation mechanism was analyzed. The results demonstrated that a dense α-Al₂O₃ oxide layer was formed on the surface of the substrate at 900 °C, which inhibited the outward diffusion of Ti and made the alloy more resistant to oxidation. However, when the temperature was increased to 1000 °C, the oxide layer could not effectively inhibit the outward diffusion of the Ti. In particular, the oxide formed on alloys treated 1100 °C was divided into two layers, where the inner layer was a dense α-Al₂O₃ oxide layer and the outer layer was TiO₂ oxide layer. (paper)