Study on the Corrosion of Duplex Stainless Steel Bar

The most important factor of influencing the durability of concrete bridge structure failure is reinforcement corrosion. The accelerated corrosion methods of laboratory with electricity is used to research mechanical properties of new material S23043 duplex stainless steel rusted. The maximum loss ratio of sectional area is used to express the degree of corrosion according to the corrosion status, and establish the corresponding simplified geometric model. The rule of corrosion rate changing with time is obtained and the regression equation of nominal yield strength, nominal ultimate strength and elongation with corrosion rate are resulted. Results of test reveal that S23043 duplex stainless steel bar corroded unevenly and many corrosion pits appeared on the surface. Corrosion rate appeared slow after the first fast with the conduction time. After reinforcement corrosion, The nominal yield strength, nominal ultimate strength, and elongation deteriorated in linearly with the increasing of corrosion rate, which could be considered as an reference for the durability evaluation of concrete structure and for the later engineering construction.