Research on the high-temperature oxidation properties of high-Mn and low-Ni austenitic stainless steel containing an aluminizing layer

High manganese (Mn) austenitic stainless steel substitutes expensive nickel (Ni) with more affordable Mn, thereby reducing production costs. However, its resistance to high-temperature oxidation is significantly compromised due to the formation of unstable Mn-rich oxides. To address this issue, this study investigates the application of an aluminizing layer on Fe-14Cr-10Mn-1.57Ni austenitic stainless steel to enhance its hightemperature oxidation resistance. The aluminized steel demonstrated a remarkable reduction in oxidation rate, with the surface oxidation rate constant being three orders of magnitude lower than that of the unaluminized stainless steel after exposure to 750 degrees C for 500 h. This improvement is attributed to the formation of a dense Al2O3protective layer, which significantly enhances oxidation resistance. Furthermore, the study reveals a gradient in oxidation resistance between the aluminized surface and the core material, a phenomenon not previously reported in high-Mn, low-Ni steels. The primary oxidation mechanism is driven by the dense Al2O3 layer, which acts as a barrier, preventing the diffusion of oxygen to the steel substrate. These findings provide a cost-effective solution for enhancing the high-temperature durability of stainless steels, with potential applications in industries requiring materials with improved oxidation resistance, such as power plants and hightemperature furnaces.