Rusting behavior of a deformed 450 MPa-grade weathering steel in 5 wt.% NaCl salt spray

Effect of pre-tension deformation on the rusting behavior of S450EW weathering steel was studied through electrochemical measurements and characterizations on rust layer. The rust layers are no longer stratified and become porous on the deformed samples. Simultaneously, the occlusion effect beneath the rust layer is alleviated. Owing to the above both aspects, the rust layer keeps a composition of approximately 7 wt% γ-FeOOH, 20 wt% α-FeOOH, and 73 wt% Fe3O4/γ-Fe2O3 under each deformation degree. The deformation increases the defects in the incipient passive film, thereby promoting rust generation but leaving inadequate time for the evolution of the rust layer.