Effect of Cu on corrosion behavior of low alloy steel under the simulated bottom plate environment of cargo oil tank

The effect of Cu on the corrosion behavior of low alloy steel under the simulated bottom plate environment of cargo oil tank was investigated by using gravimetric test, SEM, EDS, XPS, XRD and electrochemical measurements. The results indicate that the corrosion resistance of 16MnCu steel was higher than that of 16Mn steel, which was related to the deposition of nano-sized Cu particles on the surface. The deposited Cu might suppress both the anodic dissolution of the ferrite and hydrogen evolution reaction on the cementite, leading to the reduction of the galvanic effect caused by the residual cementite.