Evolution of the corrosion potential of repassivating aluminium surfaces

Burstein, G.T.; Cinderey, R.J.

doi:10.1016/0010-938x(92)90075-e

Cited by 60 publications

(22 citation statements)

References 8 publications

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“…[1][2][3][4][5][6] Other related techniques have also been used to create freshly bared areas on passive samples including breaking, 7,8 guillotining, [9][10][11][12][13][14] impingement with particles, 15 and laser irradiation. [16][17][18] These studies have provided considerable insight into the nature of passivity and the kinetics of repassivation.…”

mentioning

confidence: 99%

Influence of Dichromate Ions on Corrosion of Pure Aluminum and AA2024‐T3 in NaCl Solution Studied by AFM Scratching

Schmutz

Frankel

1999

J. Electrochem. Soc.

106

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The localized corrosion of pure aluminum, AA2024-T3 alloy, and in particular the behavior of the intermetallic particles in AA2024-T3 were studied using a technique of scratching the surface with atomic force microscopy (AFM) tips. In situ AFM scratching provides information regarding the protectiveness of the surface film. Scratching of aluminum by rastering the surface with the AFM tip in contact mode in 0.5M NaCl resulted in accelerated uniform dissolution in the rastered area. Slow pumping of the solution through the AFM cell during scratching, however, resulted in the development of sustained localized corrosion. Scratching in a stagnant 0.5 M NaCl solution containing 10 -4 M Na2Cr 2 O 7 also resulted in the development of large pits. For higher dichromate concentrations (0.005 and 0.05 M), neither accelerated dissolution nor pitting was observed, most probably because of the formation of harder chromium containing surface oxide. AFM scratching of AA2024-T3 in 0.01 M NaCl resulted in the immediate dissolution of the Al-Cu-Mg particles because of a destabilization of the surface film during light scratching. The addition of very dilute concentrations of dichromate (10 -4 M) to 0.5 M NaCl completely suppressed the corrosion of the Al-Cu-Mg particles during AFM scratching, but breakdown in the matrix occurred in a similar fashion as for pure aluminum. The addition of 0.005 M dichromate to 0.5 M NaCl again suppressed localized breakdown for low applied force during scratching, but pits formed at the Al-Cu-Mg particles at high forces. Higher dichromate concentration (0.05 M) did not completely suppress the localized breakdown at Al-CuMg particles, but the amount and lateral spreading of the dissolution was much smaller.

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mentioning

confidence: 99%

Influence of Dichromate Ions on Corrosion of Pure Aluminum and AA2024‐T3 in NaCl Solution Studied by AFM Scratching

Schmutz

Frankel

1999

J. Electrochem. Soc.

106

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“…Burstein et al [19][20][21][22][23][24] found that the free corrosion potential of freshly generated aluminum surface increased linearly with the logarithm of time during repassivation as the result of oxide film growth. The linear relationship of corrosion potential (E) and log time (t) is suggested to follow Eq.…”

Section: Resultsmentioning

confidence: 99%

“…[19][20][21][22][23][24] This relationship between OCP and immersion time has been utilized to study the growth kinetics of oxide film formed on the bare metal surface [25][26][27][28][29][30][31] as well as at the coating/metal interface.…”

Section: 6mentioning

confidence: 99%

Growth Behavior of Initial Product Layer Formed on Mg Alloy Surface Induced by Polyaniline

Luo

Wang

Guo

et al. 2015

J. Electrochem. Soc.

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The quality of the interfacial protective layer induced by polyaniline (PANI) has been claimed to play a crucial role for the enhanced corrosion protection of Mg alloy, but its growth behavior is not well understood. Here some composition, structure and growth kinetics of the protective layer formed at the PANI-emeraldine base (EB) coating/AZ91D Mg alloy interface were investigated to explore the growth mechanism. Upon immersion in 0.5 M NaCl solution, the growing interface layer under EB coating exhibited a fast passivation rate and an increased corrosion resistance, which was largely influenced by ion concentration. XPS depth profiles showed that the EB-induced layer was a mixture of MgO and Mg(OH) 2 , in which no significant bi-layer structure existed and MgO was dominant throughout the bulk film. These observations suggest that the interaction between EB and Mg can promote the faster growth of a stable MgO-rich layer mixed with Mg(OH) 2 probably by solid reaction. Meanwhile less hydration of MgO and dissolution-precipitation reaction occur, thus leading to less Mg(OH) 2 in the outer layer. Magnesium alloys have drawn great attention in automotive and aerospace industry due to their excellent properties such as low density and high specific strength. However, limited corrosion resistance of such alloys has retarded their widespread applications. To improve the corrosion resistance of Mg alloys, numerous coating techniques have been explored, among which organic coating containing corrosion inhibiting pigments is an economical and effective method in industry. One important pigment for Mg alloys is polyaniline (PANI) including emeraldine salt form (ES) and emeraldine base form (EB). 1-6Its highly efficient corrosion-protection performance for Mg alloys has been shown to be competitive to a chromate-pigmented coating. Additionally, self-healing capability was also found on a hybrid solgel/PANI coated Mg alloy upon immersing in Harrison's solution, where no pitting or filiform corrosion occurred around the scratched area while a protective layer was formed.8 Sathiyanarayanan et al. 1 and Wang et al. 8 observed that, after an initial decrease upon immersion in corrosive electrolytes, the complex impedance of PANI coated Mg alloy recovered, which was attributed to the formation of a protective layer. The different chemical composition on the EB-induced protective layer surface was already confirmed by X-ray photoelectron spectroscopy (XPS) in comparison with that formed underneath a varnish coating. 2,6The mechanism of PANI promoting a protective layer formation has been mostly supported by extensive studies in various metal systems.9-14 Nevertheless, few works have been done to understand the protective layer growth behavior. The most intractable issue of how the interaction between PANI and metal induces the protective layer growth still remains unsolved.9 This is attributed primarily to the great difficulty in in-situ investigation on the growth kinetics of interfacial layer formed beneath a coating. Electroche...

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“…An analysis of this behavior has been carried out by monitoring potential-or current-transients after mechanically stripping the oxide films. Ford et al 19) and Burstein et al [20][21][22][23][24][25][26][27][28] have reported a re-passivation mechanism after removal of passive oxide film by the mechanically stripping technique. There are however problems with the mechanical film stripping techniques, such as low stripping rates, difficult to controling stripping area size of the oxide film and contamination from the stripping tools.…”

Section: Introductionmentioning

confidence: 99%

Analysis of the Initial Stage of Localized Corrosion on Zn and Zn Alloy Coated Steels by Photon Rupture Method

Sakairi

Itabashi²,

Takahashi

2005

ISIJ Int.

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A photon rupture method, film removal by a focused pulse of pulsed Nd-YAG laser beam irradiation, has been developed as it enables oxide film stripping at extremely high rates without contamination from the film removal tools. In the present study, Zn and Zn-5mass%Al alloy coated steel specimens covered with protective nitrocellulose film were irradiated with a focused pulse of a pulsed Nd-YAG laser beam at a constant potential in 0.5 kmol m Ϫ3 H 3 BO 3 -0.05 kmol m Ϫ3 Na 2 B 4 O 7 (pHϭ7.4) with/without 0.05 kmol m Ϫ3 of chloride ions to investigate the initial stage of localized corrosion. At low potentials, both samples reformed oxide film after the nitrocellulose films were removed by this method. The oxide film formation kinetics of Zn-55mass%Al follow an inverse logarithmic law, in agreement with Cabrera-Mott theory. However, at high potentials, localized corrosion producing corrosion products occured at the area where nitrocellulose film was removed. The dissolution current of the Zn coated steel samples is higher than that of Zn-5mass%Al coated samples at the same applied potential.

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Evolution of the corrosion potential of repassivating aluminium surfaces

Cited by 60 publications

References 8 publications

Influence of Dichromate Ions on Corrosion of Pure Aluminum and AA2024‐T3 in NaCl Solution Studied by AFM Scratching

Influence of Dichromate Ions on Corrosion of Pure Aluminum and AA2024‐T3 in NaCl Solution Studied by AFM Scratching

Growth Behavior of Initial Product Layer Formed on Mg Alloy Surface Induced by Polyaniline

Analysis of the Initial Stage of Localized Corrosion on Zn and Zn Alloy Coated Steels by Photon Rupture Method

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