Effect of V content on high temperature oxidation resistance of S30403 austenitic stainless steel

In this study, the high-temperature oxidation resistance of six variants of S30403 austenitic stainless steel, differing in V content, was investigated at 700 and 800 °C under air atmosphere using the static discontinuous oxidation weight gain method. The results demonstrate that V exhibits a negative impact on the high-temperature oxidation resistance of austenitic stainless steel at 700 and 800 °C. As the V content in the steel rises, the oxidation rate also tends to elevate, with the highest values recorded at 0.1138 g m^-2 h^-1 at 700 °C and 0.4707 g m^-2 h^-1 at 800 °C, respectively. The V element in the V-containing steel is uniformly distributed in the matrix and oxide film, which promotes the internal oxidation of Cr and Si elements. The content of Cr₂O₃ and SiO₂ oxides on the surface decreases, and the Mn and Fe elements diffuse outward through the oxide film to form spinel structure MnCr₂O₄. The oxide film on the steel's surface experiences a gradual decline in its continuity and compactness, which consequently leads to a decrease in the steel's high-temperature oxidation resistance.