High temperature oxidation behavior and mechanism of Ti3SiC2–SiC nanocomposites in air

Abstract In this work, the oxidation kinetics and morphology of the oxide phases of Ti 3 SiC 2 –SiC nanocomposites in air from 1000 to 1400 °C is reported. The incorporation of ultra-fine SiC were found to have beneficial effects on the oxidation behavior of Ti 3 SiC 2 , and the weight gain decreased with the increment of SiC. The parabolic rate constant of Ti 3 SiC 2 –30 vol.%SiC composite oxidized at 1200 °C for 12 h decreased about one order of magnitude compared to that of the monolithic Ti 3 SiC 2 . At the same time, the thickness of the oxide scale as well as the oxide surface grain size of Ti 3 SiC 2 –30 vol.%SiC composite changed little with the prolonging oxidation time. At above 1200 °C, however, the oxidation process speeded up, and the adhesive and protective oxide scales were destroyed. The worsening oxidation resistance of Ti 3 SiC 2 and the passive–active oxidation transition of ultra-fine grain size of SiC were the possible reasons.