Effect of La on the Corrosion Behavior and Mechanism of 3Ni Weathering Steel in a Simulated Marine Atmospheric Environment

The corrosion behavior and mechanism of 3Ni weathering steel in a simulated oceanic atmospheric environment are investigated in order to comprehend the impacts of La, as determined through electrochemical analysis and rust layer characterization. The results of this study demonstrate that the addition of La enhances the corrosion resistance of 3Ni weathering steel in the marine atmospheric environment, thereby reducing the corrosion rate and improving the protection of the rust layer. The influence of La on corrosion resistance can be attributed to two primary factors. Firstly, La functions as a grain refiner, minimizing the potential difference of the micro-regions on the substrate surface, thereby significantly reducing the corrosion of bare steel in the marine environment. Secondly, La inhibits the process of Fe 3 O 4 oxidation back to γ-FeOOH during corrosion at the local site, thus decreasing the formation of γ-FeOOH and enhancing the charge transfer resistance. This research work may serve as a reference for expanding the application of rare earth elements in the field of weathering steel.