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In this paper, we reported tie oxidation behaviour of Ti(2)AlN films on polycrystalline Al(2)O(3) substrates. The Ti(2)AlN films composed mainly of nanolaminated MAX phase was obtained by first depositing Ti-Al-N films using reactive sputtering of two elemental Ti and Al targets in Ar/N(2) atmosphere and subsequent vacuum annealing at 800 degrees C for 1 h. The Ti(2)AlN films exhibited excellent oxidation resistance and thermal stability at 600-900 degrees C in air. Very low mass gain was observed. At low temperature (600 degrees C) no oxide crystals were observed on film surface. Blade-like theta-Al(2)O(3) fine crystals formed on film surfaces at 700-800 degrees C. At high temperature (900 degrees C), firstly theta-Al(2)O(3) formed on film surface and then transformed into alpha-Al(2)O(3). At 700-900 degrees C, a continuous Al(2)O(3) layer formed on Ti(2)AlN films surface, acting as diffusion barrier preventing further oxidation attack. The mechanism of the excellent oxidation resistance of Ti(2)AlN films was discussed based on the experimental results.