For example, carbon steels are commonly used in infrastructure such as reinforcing bars in concrete, structural beams, pipelines, bridges, and railway industries. Therefore, understanding structural and electronic modulation by adding carbon into the iron matrix is of great importance for deriving superior corrosion resistance strategies. However, atomistic simulation (DFT and MD) studies in this area are limited, and there is an urgent need to investigate the atomic-level interactions and electronic properties of iron-carbon systems to understand how carbon alters the local electronic environment and structural stability, which in turn influences corrosion.