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In marine engineering structures, the combination of different materials is inevitable, and the risk of galvanic corrosion is common. In this study, the effects of temperature on the corrosion behavior of 5083 aluminum alloy and Q235 steel in 3.5% NaCl solution were studied by scanning Kelvin probe, stereomicroscopy, X-ray diffraction, and electrochemical analysis. When the 5083 aluminum alloy and Q235 steel were coupled, the 5083 aluminum alloy was the anode, and its corrosion rate was accelerated. Results showed that with increasing temperature, the galvanic potential shifted to slightly more negative values, the galvanic current density increased, and the increase in temperature accelerated the galvanic corrosion rate. A galvanic corrosion simulation model was established, the polarization curve fitting parameters of 5083 aluminum alloy and Q235 steel were used as boundary conditions, and the potential distribution and current density distribution on the electrode surface were simulated by the finite element method. Simulation results were generally consistent with experimental results.

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Metal materials are susceptible to corrosion and microbiologically influenced corrosion(MIC) is very common in marine environment, which refers to a kind of electrochemical corrosion induced by the bacteria and their metabolic activities. In this study, electrochemical methods and scanning electron microscopy(SEM) were used to study the corrosion behavior of 10MnNiCrCu steel influenced by Acinetobacter sp. in a simulated marine environment. Electrochemical measurement results showed that the capacitance arc radius and charge transfer resistance of 10MnNiCrCu steel in Acinetobacter system were larger than those in sterile system, and the corrosion current density was lower, indicating a better corrosion resistance in the presence of Acinetobacter. The corrosion morphology observation showed that a protective biofilm/corrosion product film formed on the surface of the 10MnNiCrCu steel, which hindered the charge transfer at the interface between the metal and the solution, thereby inhibiting the corrosion. However, during the corrosion process, the partial detachment of the film led to the formation of a galvanic cell and accelerated the corrosion to a certain extent.

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