High Temperature Oxidation Behavior of (Ti, Al) C Ceramic Coatings on Carbon Steel Prepared by Electrical Discharge Coating in Kerosene

摘要

Multi-component metal ceramic coating(Ti, Al)C was prepared on the 0.45% carbon steel by electrical discharge coating (EDC) in a hydrocarbon medium. The coating of the samples before and after oxidation was analyzed by different methods including X-ray diffraction (XRD), scanning electron spectroscopy (SEM) and energy disperse spectroscopy (EDS). The thermogravimetric technique was used to approximate the kinetics of oxidation of the coated and the uncoated samples. The results indicated that the thickness of the coating was about 20μm, and the composition of the ceramic coating mainly consisted of (Ti, Al) C and a little Ti_3AlC. An oxide film with compact structure formed after 600°C oxidation for 200h, and it was mainly composed of Al_2O_3 and TiO_2, which inhibited further oxygen diffusion into the coating. The (Ti, Al) C ceramic coating possessed slow oxidation rate and high temperature oxidation resistance.