Hot corrosion of Ti3SiC2-based ceramics coated with Na2SO4 at 900 and 1000 °C in air

The hot corrosion behavior of polycrystalline Ti3SiC2 under thin films of Na2SO4 was studied at 900 and 1000 degreesC in air. The microstructure and composition of the scales were investigated by scanning electron microscope/energy dispersive spectroscope and X-ray diffraction. The results demonstrated that Ti3SiC2 suffered from serious attack during hot corrosion at 900 and 1000 degreesC. The corroded scale had a duplex microstructure, the outer layer consisted of coarse grains with pores, the inner layer consisted of fine grains and was compact. The whole corroded layer consisted of a mixture of TiO2 and SiO2 after hot corrosion attack, which was different from the scale formed during the oxidation of Ti3SiC2 in air. (C) 2002 Published by Elsevier Science Ltd.