 Q235B mild steel has the advantages of good mechanical properties, welding properties, and low cost. It is widely used in bridges, energy fields, and marine equipment. However, low carbon steel is prone to serious pitting corrosion in urban water and sea water with high chloride ions, Cl-, this work provides a feasible strategy for an anti-corrosion design. This article was authored by Xinhual Yang, Pinggui Wu, Lingxiao Lan, and others.