On the role of mechanical deformation in the environmental degradation of 310S stainless steels in supercritical carbon dioxide

The corrosion behavior of 310 S stainless steel with and without mechanical deformation (surface grinding and cold work) has been investigated. The experimental results show that mechanical deformation enhances corrosion resistance of materials. Multilayer oxide scale is observed on the material without mechanical deformation, which owns a loose structure and contributes to the severe carburization of the material. Thin and protective oxide scale (Cr/Mn-rich and Si-rich) is formed on the material after mechanical deformation, which hinders the internal carburization. Mechanical deformation reduces grain size and makes grain boundary diffusion become predominant, which improves the corrosion resistance of materials.