Abstract：In order to study the effect of rare earth on corrosion resistance of mooring chain steel, the mooring chain steel with different Ce content is smelted. Using the powerful function of rare earth in steel to further improve the corrosion resistance performance of mooring chain. The test steel 22MnCrNiMo is melted by a 10 kg vacuum induction furnace, and then hot- rolled to 17 mm plate, secondary water- quenched at 930 °C and tempered at 620 °C. The effect of Ce on the corrosion resistance properties of steel 22MnCrNiMo has been studied by using weight method, polarization curve and AC impedance method. The results show that the corrosion resistance of steel containing different Ce is improved after adding the rare earth Ce and the optimum Ce content in steel is 0.143%. Under this content, the microstructure of the experimental steel is more uniform, inclusions in steel are transformed into rare earth ball inclusions with high stability. So the corrosion rate of the steel in any corrosion period is the minimum, and the corrosion marks are the lightest after rust removal. The arc radius reaches the maximum, which indicates that the reaction resistance is also the greatest, the anodic polarization curve is located at the left of other steel anode polarization curves, indicating that with the decrease of the anode current density, the reaction resistance increases. Thus, Ce addition can improve the corrosion resistance properties of steel 22MnCrNiMo, and as the Ce mass fraction is 0.143%, the steel 22MnCrNiMo has the optimum corrosion- resisting properties.
2019, Vol. 29 
