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Titanium alloys are attractive for structural applications, particularly in aerospace engineering, owing to their outstanding balance of mechanical properties with relatively low density. However, their application is limited to moderate temperatures because of their poor oxidation behavior above 500°C. Due to the high oxygen solubility in titanium, its oxidation process is complex and only partially understood. To elucidate the oxidation mechanism of titanium, pure titanium samples have been oxidized for four hours at 800°C. A lower temperature of 600°C was also tested. In situ oxidation experiments were performed using a heating stage under an argon environment which enabled a real-time observation of the oxidation process and identification of the resulting oxide products through Raman spectroscopy. Further analysis by scanning electron microscopy allowed the characterization of the surface oxide morphology. A continuous growth of a rutile oxide layer on pure titanium was observed after oxidation at 800°C followed by slow cooling rates. A notable observation is that the oxide evolves primarily during cooling rather than at the hold temperature, which reveals that all the oxygen incorporated at temperature is dissolved into the metal as interstitials. The oxidation process of titanium and the complexity of its products are found to depend strongly on the oxidation parameters as well as the exact composition of the material.