Corrosion Behavior of A588 Weathering Steel in Simulated Atmospheric Environments with High Nitrogen Oxide and Sulfur Di

A588 weathering steel is known for its high resistance to corrosion and weathering, making it a popular choice for outdoor structures such as bridges, buildings, and monuments. However, exposure to high levels of nitrogen oxide (NOx) and sulfur dioxide (SO2) can accelerate the corrosion process and reduce the lifespan of these structures. In addition, the effect of creep loading and fatigue loading on the corrosion behavior of A588 weathering steel under simulated atmospheric environments with high NOx and SO2 content has not been extensively studied.

Experimental Methodology:

The study was conducted by exposing A588 weathering steel samples to simulated atmospheric environments with varying levels of NOx and SO2 content. The samples were subjected to creep loading and fatigue loading to simulate the effects of long-term stress and cyclic fatigue on the corrosion behavior. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests were performed to evaluate the corrosion resistance of the samples under different conditions.

Results and Discussion:

The results showed that the corrosion rate of A588 weathering steel increased with increasing levels of NOx and SO2 in the simulated atmospheric environments. The presence of these pollutants led to the formation of aggressive chemical species such as nitric acid and sulfuric acid, which accelerated the corrosion process. The corrosion rate was higher under fatigue loading compared to creep loading, indicating that cyclic stress can exacerbate the effects of environmental degradation.

EIS analysis revealed that the corrosion resistance of A588 weathering steel decreased with increasing levels of NOx and SO2 content in the simulated atmospheric environments. The impedance values decreased, indicating that the samples were becoming more susceptible to corrosion. The potentiodynamic polarization tests showed that the corrosion current density increased with increasing levels of NOx and SO2 content, confirming the accelerated corrosion process. The polarization curves also showed that fatigue loading had a greater effect on the corrosion behavior compared to creep loading, as the corrosion current density was higher under fatigue loading.

Conclusion:

In conclusion, the corrosion behavior of A588 weathering steel is influenced by the levels of NOx and SO2 in the simulated atmospheric environments. Exposure to high levels of these pollutants accelerates the corrosion process, and the effects are exacerbated under cyclic stress. The corrosion resistance of the samples decreased with increasing levels of NOx and SO2 content, as indicated by EIS and potentiodynamic polarization tests. The results of this study have important implications for the design and maintenance of outdoor structures made of A588 weathering steel in areas with high levels of NOx and SO2 pollution.