Effect of Si on high temperature oxidation of 30Cr13 stainless steel

The effect of Si on the high temperature oxidation behavior of the 30Cr13 martensitic stainless steels was investigated. The underlying mechanism was further discussed by oxidation kinetics curves, scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. It was observed that the addition of Si can significantly reduce the mass gain per unit area and the oxidation rate of the experimental steels. With the increase of Si content, the film surface composed of the wheat-like oxides turned into the small granular oxides after oxidation for 120 h. The SiO2 film formed on the metal substrate inhibited the outward diffusion of the metal cation and the inward diffusion of the oxygen anion; thus, the high temperature oxidation resistance was enhanced.