Oxidation resistance of Cr-modified MoSi2 composites at high temperature

Alloying is an important measure to improve the oxidation resistance of MoSi2. Cr-modified MoSi2 composites were prepared by hot pressing sintering in this study, and their oxidation behaviors at different temperatures were examined by XRD, SEM and EDS. The results show that the MoSi2 matrix forms CrSi2 compound with the increase of Cr content, which is conductive to the formation of surface oxide scale. Besides, the microstructure study shows that the modified element Cr promotes the formation of SiO2 protective scale at 500 °C–900 °C. When oxidized at 1300 °C, Cr2O3 in the form of Cr oxidation dissolved in MoSi2 is dispersed in the SiO2 oxide scale. The high temperature oxidation resistance of MoSi2 composites is improved by adding Cr modified element.