High-Temperature Oxidation Behavior of Medium-Manganese Austenitic Steel

The high-temperature oxidation behavior of medium-manganese austenitic steel is investigated. The double-layered oxide scale is formed in the investigated samples. The outer oxide layer consists of (Fe,Mn)-rich oxides, while the inner oxide layer is mainly composed of AB₂O₄ spinel oxides. When the oxidation temperature is 800 °C, a region composed of oxide and ferrite is formed in the substrate surface layer. When the oxidation temperature is 900 and 1000 °C, there is no such region observed in the substrate surface layer. Although the content of Al in the Fe–Mn–Al sample and the content of Si in the Fe–Mn–Si sample are relatively lower than the content of Cr in the Fe–Mn–Cr sample, the oxidation resistance of the Fe–Mn–Al and Fe–Mn–Si samples is still better than that of the Fe–Mn–Cr sample. The oxidation resistance of the Fe–Mn–Cr–Al and Fe–Mn–Cr–Si samples is also better than that of the Fe–Mn–Cr sample. The addition of Al and Si can improve the oxidation resistance of the Fe–Mn–Cr sample. Besides, the oxidation resistance improvement effect of adding Si to the Fe–Mn–Cr sample is better than that of adding Al to the Fe–Mn–Cr sample.