Study on the corrosion resistance of the repassivation film of austenitic stainless steel

The spontaneous passivation film of austenitic stainless steel is very thin,and it is easily destroyed by corrosion in anionic environment.The passivation film makes stainless steel only have dull metallic luster and metallic color.A thin sheet of chemical film can be formed on the surface of metals by repassivation technology,it can not only improve the corrosion resistance of stainless steel but also make the surface of stainless steel present different colors by light interference.Some test pieces are passivated by acidic chemical coloring,and the corrosion tests of the passivated test pieces and original test pieces are carried in FeCl_3 solution.The experimental results of overall corrosion and spot corrosion all show that the corrosion resistance of the passivated test pieces are better than that of the original test pieces.The metal passivation technology is green,economic and practical,and therefore it has good prospects of application.