A co-ordinated study of the passivation of alloy steels by plasma source mass spectrometry and x-ray photoelectron spectroscopy—II. growth kinetics of the passive film

Castle, J. E.; Qiu, J. H.

doi:10.1016/0010-938x(89)90011-5

Cited by 22 publications

(34 citation statements)

References 16 publications

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“…in the absence of pre-passivation. These observations, repeated in three distinct local areas of the samples, confirm that the pre-passivation in the absence of chlorides increases the resistance to passivity breakdown and the initiation of localized corrosion as reported previously from macroscopic measurement [10,11]. They show that, in the conditions tested here, metastable pitting can be blocked at the micrometer scale and at least mitigated at the nanometer scale.…”

Section: Passivation Transients and Surface Topographysupporting

confidence: 90%

Chloride-induced alterations of the passive film on 316L stainless steel and blocking effect of pre-passivation

Wang

Seyeux

Zanna

et al. 2020

Electrochimica Acta

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Electrochemical polarization measurements were combined with surface analysis by Time of Flight Secondary Ion Mass Spectroscopy (ToF-SIMS), X-Ray Photoelectron Spectroscopy (XPS) and Atomic Force Microscopy (AFM) to study the alterations of the passive film on 316L austenitic stainless steel induced by the presence of chlorides in sulfuric acid electrolyte. The work was performed at a stage of initiation of localized corrosion preceding metastable pitting at the micrometer scale as verified by current transient analysis and AFM. The results show that Clions enter the bilayer structure of the surface oxide already formed in the native oxide-covered initial surface state at concentrations below the detection limit of XPS (< 0.5 at%), mostly in the hydroxide outer layer where Fe(III) and Mo(IV,VI) species are concentrated but barely in the oxide inner layer enriched in Cr(III). Their main effect is to produce a less resistive passive state by poisoning dehydroxylation and further Cr(III) and Mo(IV,VI) enrichments obtained in the absence of chlorides. This detrimental effect can be suppressed by pre-passivation in a Cl-free electrolyte, which blocks the entry of chlorides in the passive film, including in the outer exchange layer, and enables the beneficial aging-induced variations of the composition to take place despite the presence of chlorides in the environment.On AISI 316L, recent surface analytical studies performed by Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) and X-ray Photoelectron Spectroscopy (XPS) [27,46,47] confirmed the bilayer structure of the passive film previously reported [21,22,27,30,32]. The native oxide film formed in air was found to already develop this bilayer structure with both the hydroxide outer and oxide inner layers enriched in Cr(III) and with Fe(III) more concentrated in the outer layer together with Mo(IV,VI). Electrochemical passivation in chloride-free sulfuric acid solution did not alter the bilayer structure and thickness of the surface oxide but promoted its Cr and Mo enrichments, owing to the lower stability and preferential dissolution of Fe(III) as previously proposed [4,16,53], and thereby increased the corrosion resistance of the passive state.In the present work, we address the alterations of the surface oxide films brought by electrochemical passivation in Cl-containing sulfuric acid solutions. Potentiodynamic and potentiostatic polarization measurements were used to define the electrochemical conditions best suited to alter the passive state without initiating localized corrosion (i.e metastable pitting) at the micrometer scale. ToF-SIMS and XPS were applied to characterize the bilayer structure, thickness and composition of the passive film and the entry of chlorides. Surface morphology was studied by Atomic Force Microscopy (AFM).The results provide new insight on the effect of pre-passivation on the entry of chlorides in the passive film and increased resistance to metastable pitting at the nanometer scale. ExperimentalThe same polycrystalline AISI 316...

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Section: Passivation Transients and Surface Topographysupporting

confidence: 90%

Chloride-induced alterations of the passive film on 316L stainless steel and blocking effect of pre-passivation

Wang

Seyeux

Zanna

et al. 2020

Electrochimica Acta

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“…The three O 1s components assigned to the oxide (O 2-), hydroxide (OH -) and water (H2O) ligands in the oxide film are observed at 530.3, 531.8 and 532.7 eV, respectively (Fig. 8d) [11,34]. The intensity ratio of OH -/O 2is 1.2 for the 1 h passivated sample, higher than for the native oxide-covered sample (0.9).…”

Section: Passive Filmsmentioning

confidence: 91%

Passivation-Induced Physicochemical Alterations of the Native Surface Oxide Film on 316L Austenitic Stainless Steel

Wang

Franco

Seyeux

et al. 2019

J. Electrochem. Soc.

104

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Time of Flight Secondary Ion Mass Spectroscopy, X-Ray Photoelectron Spectroscopy, in situ Photo-Current Spectroscopy and electrochemical analysis were combined to characterize the physicochemical alterations induced by electrochemical passivation of the surface oxide film providing corrosion resistance to 316L stainless steel. The as-prepared surface is covered by a ~2 nm thick, mixed (Cr(III)-Fe(III)) and bi-layered hydroxylated oxide. The inner layer is highly enriched in Cr(III) and the outer layer less so. Molybdenum is concentrated, mostly as Mo(VI), in the outer layer.Nickel is only present at trace level. These inner and outer layers have band gap values of 3.0 and 2.6-2.7 eV, respectively, and the oxide film would behave as an insulator. Electrochemical passivation in sulfuric acid solution causes the preferential dissolution of Fe(III) resulting in the thickness decrease of the outer layer and its increased enrichment in Cr(III) and Mo(IV-VI). The further Cr(III) enrichment of the inner layer causes loss of photoactivity and improved corrosion protection with the anodic shift of the corrosion potential and the increase of the polarization resistance by a factor of ~4.Aging in the passive state promotes the Cr enrichment in the inner barrier layer of the passive film.

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“…The O 1s spectra were fitted with three components O1, O2, and O3 assigned to oxide (O 2− ), hydroxide (OH − ) and water (H 2 O) ligands in the surface oxide films, respectively (see e.g., Figure 5, Table 1; Clayton and Lu, 1986;Castle and Qiu, 1989b; Biesinger et al, 2011;Maurice et al, 2015;Wang et al, 2019). The OH − /O 2− intensity ratio increases from 0.58 for the native oxide film to 1.72 after treatment at U OCP and then decreases to 1.24 after treatment at U Pass .…”

Section: Thickness and Composition Of The Surface Oxide Filmsmentioning

confidence: 99%

Mechanisms of Cr and Mo Enrichments in the Passive Oxide Film on 316L Austenitic Stainless Steel

et al. 2019

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An approach preventing contact to ambient air during transfer from liquid environment for electrochemical treatment to UHV environment for surface analysis by X-Ray Photoelectron Spectroscopy and Time-of-Flight Secondary Ion Mass Spectrometry was applied to study the mechanisms of Cr and Mo enrichments in the passive oxide film formed on 316L austenitic stainless steel. Starting from the air-formed native oxide-covered surface, exposures were conducted in aqueous sulfuric acid solution first at open circuit potential and then under anodic polarization in the passive range. At open circuit potential the thickness of the bi-layered oxide film was observed to decrease and the enrichments of both Cr(III) and Mo, mostly Mo(VI), to markedly increase as well as the film hydroxylation. This is due to preferential dissolution of the Fe(III) oxide/hydroxide, not compensated by oxide growth in the absence of an electric field established by anodic polarization. Anodic polarization in the passive domain causes the bi-layered structure of the oxide film to re-grow by oxidation of iron, chromium and molybdenum, without impacting the Cr enrichment and only slightly mitigating the Mo enrichment. De-hydroxylation of the inner layer is also promoted upon anodic polarization. These results show that the treatment of the surface oxide film in acid solution at open circuit potential enhances Cr and Mo enrichments and promotes hydroxylation. Passivation by anodic polarization allows dehydroxylation, yielding more Cr oxide, without markedly affecting the Mo enrichment, also beneficial for the corrosion resistance.

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A co-ordinated study of the passivation of alloy steels by plasma source mass spectrometry and x-ray photoelectron spectroscopy—II. growth kinetics of the passive film

Cited by 22 publications

References 16 publications

Chloride-induced alterations of the passive film on 316L stainless steel and blocking effect of pre-passivation

Chloride-induced alterations of the passive film on 316L stainless steel and blocking effect of pre-passivation

Passivation-Induced Physicochemical Alterations of the Native Surface Oxide Film on 316L Austenitic Stainless Steel

Mechanisms of Cr and Mo Enrichments in the Passive Oxide Film on 316L Austenitic Stainless Steel

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