Oxidation behavior of high Cr white iron composites reinforced with TiC and nonstoichiometric TiCxin air at 600 °C

High Cr white irons (HCWIs) are often used as high-temperature components exposed to the temperatures exceeding 500 °C. Improving oxidation resistance of HCWI components is necessary for engineering applications. In the present study, oxidation behaviors of high Cr white iron (HCWI) and its composites reinforced with 1–2 μm nonstoichiometric TiCxresulting from the decomposition of Ti3AlC2(in situ TiCx/HCWI), and 2–4 μm irregular-shape of TiC (TiC/HCWI) at 600 °C for 96 h in air were investigated. Results showed that the two composites exhibited better oxidation resistance than the pure HCWI material. The oxidation test revealed a weight loss for the unreinforced HCWI but a weight gain for the composites. Among these materials, the in situ TiCx/HCWI composite has the best oxidation resistance due to its dense and fine microstructure. Oxidative thermodynamics and oxidation mechanism were discussed. This work suggests that in situ formed TiCxis an effective reinforcement to improve the oxidation resistance of HCWIs.