Facile chromaticity approach for the inspection of passive films on austenitic stainless steel

The effect of pre-deformation on corrosion resistance of the passive film formed on 2205 duplex stainless steel

“…The MotteSchottky analysis reveals that the passive film formed on these samples exhibits n-type and p-type semiconducting characteristics irrespective of the strain level. Two slopes in passive films formed on duplex stainless steels in the solution indicate that the passive films are formed as dual layers which contain iron oxides outer layer and chromium oxides inner layer [23,24].…”

Interactions between Phosphoric/Tannic Acid and Different Forms of FeOOH

“…By employing a processing method of a chemical conversion film, the hydroxyl oxide rust layer on the iron may undertake a chemical conversion and form porous membrane barrier with good ventilation property and water permeability [11]. The excellent atmospheric corrosion resistance of the phosphoric Dhar pillar iron was attributed to the formation of a protective passive film on the surface [12]. Chemical conversion film, as inoxidizing coating of metal, reduces chemical activity of the metal and increases thermodynamic stability of steel in environmental medium.…”

“…In this study, X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectrometry (XPS), and transmission electron microscopy (TEM) were used to characterize the four types of FeOOH, as well as to investigate the interactions between FeOOH and mixed solutions containing different concentrations and proportions of phosphoric acid and tannic acid in order to provide technical basis to distinguish these types of FeOOH and enable rust layer stabilizer selection for preservation of steel, especially for iron cultural relics. [12]. Thus, the four FeOOH polymorphs were prepared to investigate their effects on iron rust.…”

Reply to comment on “New understanding of the effect of hydrostatic pressure on the corrosion of Ni-Cr-Mo-V high strength steel”

“…The investigated NiCr-Mo-V high strength steel in our paper is a Fe-based alloy with a little amount of Cr and Mo [2] that cannot induce the formation of passive film, which is totally different from the Ni-based alloy with high percent of Cr and Mo [3][4][5]referenced in the comment paper [1].Moreover, it can be seen from Fig. 5 in literature [6] that the NiCr-Mo-V high strength steel shows active corrosion characteristic in 3.5% NaCl solutionwhich is distinct from stainless steel with passive film [7]. And also, corrosion product layer has little protective effect on the steel even after a long time immersion in 3.5% NaCl solution [8].…”