Enhancing Weatherability of Cu‐Containing Weathering Steel in Simulated Tropical Marine Atmospheres: A Sulfuric Acid Patination Approach Driven by Cu Dissolution and Redeposition

Based on the dissolution and redeposition characteristics of Cu in H 2 SO 4 solution, this study examines the impact of sulfuric acid patination treatment on the weatherability of Cu‐containing weathering steel in the simulated tropical marine atmosphere. Results reveal that acid treatment improves the protective properties of the rust layer by inducing more Cu to participate in rust layer formation and causing a layered distribution of Cu in rust layers, which reduces the rust layer defects, increases the content of α‐FeOOH, reduces rust particle size, increases the diffusion resistance to corrosive species, and enlarges the thickness of the protective rust layer.