Microstructural corrosion behavior of austenitic Fe-21Mn-2.5Al-0.04C alloy in oxidizing-sulfidizing environments

Abstract

Fe-21Mn-2.5Al-0.04C alloy was exposed to SO₂-O₂ mixed gas environments at 900°C. The morphologies of the scales formed on the alloy investigated were examined by scanning electron microscopy and x-ray mapping techniques. The results showed that multilayered scales were formed, consisting of an external (FeMn)₂O₃ blocky oxide, an intermediate (FeMn)₂O₃ internal oxide, and an innermost Mn(Fe)S sulfide.