Localized Corrosion of Sputtered Aluminum and Al‐0.5% Cu Alloy Thin Films in Aqueous  HF  Solution: I . Corrosion Phenomena

Scully, J. R.; Frankenthal, R. P.; Hanson, Kristi L.; Siconolfi, D. J.; Sinclair, J. D.

doi:10.1149/1.2086675

Cited by 46 publications

(23 citation statements)

References 33 publications

(55 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The alloying element that is responsible for the localized corrosion susceptibility of the Al 2024 alloy is copper. − Despite a broad body of scientific information in support of this assertion, there is only a limited insight into the copper behavior in the aluminum matrixes, particularly during cathodic polarization. The knowledge of the cathodic behavior that exists stems from observations related to an increasing use of aluminum alloys in offshore applications where the cathodic protection under immersed conditions may become necessary for prolonged service life …”

Section: Introductionmentioning

confidence: 99%

Sorption of Sulfate and Chloride Anions on a Well-Characterized Al 2024 Electrode

et al. 1998

View full text Add to dashboard Cite

We studied sorption processes, adsorption and incorporation, of sulfate and chloride anions on the surface of well-characterized aluminum 2024 alloy using electrochemical, radiochemical, and ultrahigh-vacuum spectroscopic techniques. The measurements were carried out at an open-circuit potential and in the electrode potential range on the negative side of the open-circuit potential (cathodic polarization conditions), at various pH values. The focus was on sorption reversibility as well as on the relationship between anion's surface concentration and the electrode potential. We have found that sorption of sulfate anion is controlled by pH, surface charge, and the stability of aluminum oxide films. We have also found that adsorption of chloride is weaker than sulfate and is more irreversible since chloride incorporation occurs more readily than sulfate. The change in the alloy surface composition and morphology induced by the electrochemical treatment and anion adsorption was monitored by scanning Auger microscopy and energy-dispersive X-ray spectroscopy. The characterization exhibits copper-rich intrusions and extrusions that may act as either local cathodes or anodes in the overall alloy dissolution process. The distribution and evolution of such Cu-rich inclusions under studied experimental conditions were monitored and are reported. The dissolution of aluminum from the alloy affects both sulfate and chloride adsorption/incorporation processes. While sulfate and chloride adsorption have no effect on cathodic current measured in the studied electrode potential range, the high anion surface concentration may have a detrimental effect on the alloy stability, particularly when the beneficial influence of the cathodic polarization (protection) ends.

show abstract

Section: Introductionmentioning

confidence: 99%

Sorption of Sulfate and Chloride Anions on a Well-Characterized Al 2024 Electrode

et al. 1998

View full text Add to dashboard Cite

show abstract

“…The chemistry of defects observed for each investigated alloy was similar. The defects were primarily composed of carbon and oxygen, most likely forming metal carbonates typical for early pitting corrosion stages [58]. Small amount of chlorine was also found within defects.…”

Section: Resultsmentioning

confidence: 99%

The Influence of Microstructure on the Passive Layer Chemistry and Corrosion Resistance for Some Titanium-Based Alloys

et al. 2019

View full text Add to dashboard Cite

The effect of microstructure and chemistry on the kinetics of passive layer growth and passivity breakdown of some Ti-based alloys, namely Ti-6Al-4V, Ti-6Al-7Nb and TC21 alloys, was studied. The rate of pitting corrosion was evaluated using cyclic polarization measurements. Chronoamperometry was applied to assess the passive layer growth kinetics and breakdown. Microstructure influence on the uniform corrosion rate of these alloys was also investigated employing dynamic electrochemical impedance spectroscopy (DEIS). Corrosion studies were performed in 0.9% NaCl solution at 37 °C, and the obtained results were compared with ultrapure Ti (99.99%). The different phases of the microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Chemical composition and chemistry of the corroded surfaces were studied using X-ray photoelectron spectroscopy (XPS) analysis. For all studied alloys, the microstructure consisted of α matrix, which was strengthened by β phase. The highest and the lowest values of the β phase’s volume fraction were recorded for TC21 and Ti-Al-Nb alloys, respectively. The susceptibility of the investigated alloys toward pitting corrosion was enhanced following the sequence: Ti-6Al-7Nb < Ti-6Al-4V << TC21. Ti-6Al-7Nb alloy recorded the lowest pitting corrosion resistance (Rpit) among studied alloys, approaching that of pure Ti. The obvious changes in the microstructure of these alloys, together with XPS findings, were adopted to interpret the pronounced variation in the corrosion behavior of these materials.

show abstract

“…The exemplary results, obtained for Ti-6Al-7Nb alloy are summarized on Figure S4 (Supporting Information), while the chemistry of defects observed for each investigated alloy were similar. The defects are primarily composed of carbon and oxygen, most likely forming metal carbonates typical for early pitting corrosion stages [45]. Small amount of chlorine was also recorded within defects.…”

Section: 34chronoamperometry Measurementsmentioning

confidence: 98%

Exploring the Influence of the Microstructure on the Passive Layer Chemistry and Breakdown for Some Titanium-Based Alloys in Normal Saline Solution

El-Bagoury¹,

Ibrahim²,

Ali³

et al. 2019

Preprint

View full text Add to dashboard Cite

The effect of microstructure and chemistry of passive films on the kinetics of passive layer growth and passivity breakdown of some Ti-based alloys, namely Ti-6Al-4V, Ti-6Al-7Nb and TC21 alloys was studied. The rate of pitting corrosion was evaluated using cyclic polarization measurements. Chronoamperometry was applied to assess the passive layer growth kinetics and breakdown. Microstructure influence on the uniform corrosion rate of these alloys was also investigated employing Tafel extrapolation and dynamic electrochemical impedance spectroscopy. Corrosion studies were performed in 0.9% NaCl solution at 37 oC, and the obtained results were compared with ultrapure Ti (99.99%). The different phases of the microstructure were characterized by X-ray diffraction and scanning electron microscopy. Chemical composition and chemistry of the corroded surfaces were studied using X-ray photoelectron analysis. For all studied alloys, the microstructure consisted of α matrix, which was strengthened by β phase. The highest and the lowest values of the β phase’s volume fraction were recorded for TC21 and Ti-Al-Nb alloys, respectively. The uniform corrosion rate and pitting corrosion resistance (Rpit) of the studied alloys were enhanced following the sequence: Ti-6Al-7Nb < Ti-6Al-4V << TC21. The corrosion resistance of Ti-Al-Nb alloy approached that of pure Ti. The obvious changes in the microstructure of these alloys, together with XPS findings, were adopted to interpret the pronounced variation in their corrosion rates.

show abstract

Localized Corrosion of Sputtered Aluminum and Al‐0.5% Cu Alloy Thin Films in Aqueous HF Solution: I . Corrosion Phenomena

Cited by 46 publications

References 33 publications

Sorption of Sulfate and Chloride Anions on a Well-Characterized Al 2024 Electrode

Sorption of Sulfate and Chloride Anions on a Well-Characterized Al 2024 Electrode

The Influence of Microstructure on the Passive Layer Chemistry and Corrosion Resistance for Some Titanium-Based Alloys

Exploring the Influence of the Microstructure on the Passive Layer Chemistry and Breakdown for Some Titanium-Based Alloys in Normal Saline Solution

Contact Info

Product

Resources

About