Abstract <p>In this study, for the first time, the simultaneous effect of cold working and chloride concentration on micro-galvanic corrosion of 2101 lean duplex steel (LDX) in citric acid environment (the most important industrial simulator in the food industry) was comprehensively studied. Using electrochemical tests (CV, PDP and EIS) along with detailed microstructural analysis, a two-phase γ/α structure showed different corrosion behavior while α acted as the weaker phase, also the precipitation of Cr₂N and M₂₃C₆ at grain and phase boundaries made sensitive areas to pitting corrosion. Cold working first deformed the γ phase and increased the hardness of both phases to 54.7% (γ) and 11% (α), respectively, by inducing strain-induced martensite (SIM) in γ and increased dislocation density. The main innovation of this work is in demonstrating the positive effect of cold working on strengthening the surface passive layer, while chloride significantly accelerates the corrosion rate, the application of 15% and 30% strain causes a 23.5% and 46.7% reduction in the corrosion current density (i_corr) and at 45% strain, a completely passive behavior dominates. The main mechanism of controlled pitting reduction is the homogenization of the surface energy of the phases and the disappearance of the galvanic potential difference between γ and α. These findings provide precise guidance for optimizing post-processing and improving the durability of steel parts in corrosive food environments.</p> Graphical Abstract <p></p>