Study on Corrosion Behavior of Weathering Bridge Steel in Simulated Industrial Atmosphere

Abstract

For providing a scientific basis for the applicability of weathering bridge steels in industrial atmospheric environments with different levels of pollution， the influence of industrial atmospheric environments on the corrosion behaviors of typical weathering bridge steels was simulated. The corrosion behaviors in industrial atmospheric environments of two kinds of weathering bridge steels， Q345qNH and Q420qNH， were studied through the periodic infiltration accelerated corrosion test. Furthermore， the applicability of these two kinds of weathering bridge steels in NaHSO3 solutions with different concentrations in simulated industrial atmospheric environments was investigated by weight loss method，electrochemical analysis and macroscopic morphology observation. Results showed that the corrosion resistance of Q420qNH weathering steel was better than Q345qNH in simulated industrial atmospheric environments. The corrosion rate of these two weathering bridge steels increased first and then decreased with the extension of the corrosion time，and the corrosion rate was the highest at 24 h. As the concentration of NaHSO3 solution increased，the corrosion rate increased. When the solution concentration reached 0.5%，the corrosion of the Q345qNH sample was continuously accelerated， indicating that the applicability of Q345qNH was limited in this case.

Keywords

• weathering bridge steel|simulated industrial atmospheric environment|pollutant concentration