Corrosion characteristics of S23043 duplex stainless steel bars

Reinforcement corrosion is a main cause of durability deterioration of reinforced concrete structures. In recent years, stainless steel bars have been gradually applied to engineering practice because of its good corrosion resistance. However, under harsh environments such as chloride ion exposure, stainless steel bars will rust. Therefore, scholars began to study the corrosion characteristics of stainless steel bars. Previous studies mainly focused on the corrosion of steel bars in the zero-strain state, but steel bars in actual structures usually bear a sustained load resulting in initial strains. In this study, the corrosion characteristics of S23043 duplex stainless steel bars (S23043) under different strain levels were investigated by using acceleration corrosion tests and tensile tests under constant strain conditions in a chloride environment. The results showed that corrosion degree of S23043 increased by about 20% as the strain levels increased from 0 to 1 × 10−3. As the corrosion degree increased, the strength of stainless steel bars decreased, and the ductility decreased significantly. Finally, the mechanical properties of the stainless steel bars after corrosion were compared with those of ordinary steel bars.