Research on corrosion performance of Q235B steel in industrial coastal atmospheric environment

This study aims to obtain the effect of SO₂ on the corrosion of Q235B low carbon steel in simulated coastal industrial atmospheres.The corrosion performance of the steel in the simulated atmospheres was studied using wet/dry cyclic corrosion test (CCT), electrochemical testing analysis, scanning electron microscopy, X-ray diffraction, and COMSOL finite element simulation methods. As a result the influence of SO₂, the corrosion rate of Q235B steel increases rapidly in the initial stage of corrosion, and gradually decreases in the later stages, eventually stabilizing. There is a gradual increase in ferrite content on the surface of the steel during the initial stage of corrosion. In addition, the main components of the rust layer α-FeOOH and γ-FeOOH, and high concentrations of SO₂ promote α-FeOOH formation and inhibit γ-FeOOH formation.