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A graded NiCrAlYRe coating was prepared by combining arc ion plating (AIP) with chemical vapor deposition (CVD) aluminizing. Quasi-isothermal oxidation tests of the graded NiCrAlYRe coating and the conventional NiCrAlYRe coating were performed in air at 900, 1000 and 1100 A degrees C for up to 1000, 1000 and 200 h, respectively. The results showed that the graded NiCrAlYRe coating exhibited better long time oxidation resistance than the conventional NiCrAlRe coating. This favorable oxidation behavior was attributed to the rapid formation of a protective alpha-Al(2)O(3) scale and a sufficient Al reservoir. The structures and morphologies of oxide scales varied under different oxidation conditions. theta-Al(2)O(3) was observed on both coatings during oxidation at 900 A degrees C, however, the graded coating showed more favorable conditions for theta-Al(2)O(3) to grow than the conventional coating. For the graded coating, phase transformation from theta-Al(2)O(3) to alpha-Al(2)O(3) resulted in a sharp decrease in the parabolic rate constant k(p) between 900 and 1,000 A degrees C.