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The hot corrosion behavior of Na2SO4-coated Ti2AlC was investigated by means of thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy/energy dispersive spectroscopy. This carbide displays good hot corrosion resistance below the melting point of Na2SO4 while the corrosion attacks become virulent when the salt is molten. A protectively continuous Al2O3 layer forms and imparts good corrosion resistance, and consequently, the corrosion kinetics is generally parabolic at 850 degrees C. However, porous oxide scales fail to protect the Ti2AlC substrate at 900 and 1000 degrees C. The segregation of sulfur at the corrosion scale/substrate interface accelerates the corrosion of Ti2AlC. Furthermore, a convenient and efficient pre-oxidation method is proposed to improve the high-temperature hot corrosion resistance of Ti2AlC. An Al2O3 scale formed during pre-oxidation treatment can remarkably restrain the infiltration of the molten salt into the substrate and prevent the substrate from severe corrosion attacks. (c) 2005 Elsevier Ltd. All rights reserved.