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High temperature oxidation behavior of the Cr(2)AlC coating was investigated at 900-1100 degrees C. During the oxidation, a continuous Al(2)O(3) scale formed, resulting in the improvement of the oxidation resistance of the substrate. Meanwhile, the oxidation induced depletion of Al within the Cr(2)AlC coating resulted in the transformation of Cr(2)AlC to Cr-C phases. Compared with bulk Cr(2)AlC, the Cr(2)AlC coating possessed similar oxidation behavior, but with higher oxidation rate. This is because a great number of columnar grain boundaries existed in the as-deposited coating, through which oxygen and nitrogen could diffuse inwardly, resulting in the internal oxidation and nitridation. (C) 2011 Elsevier Ltd. All rights reserved.