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The corrosion inhibition of self-assembled octadecylphosphonic acid (ODPA) layers on non-oxidized and pre-oxidized copper and Langmuir-Blodgett deposited ODPA layers on pre-oxidized copper was investigated under a simulated indoor atmospheric corrosion environment containing 80% RH and 100 ppb formic acid. The corrosion process was monitored in-situ with infrared absorption/reflection spectroscopy, and the corrosion products were further characterised by grazing incidence X-ray diffraction. Nano-FTIR microscopy was used to reveal the nature, size, and distribution of the corrosion products on the nanoscale. The combination of pre-formed cuprite and ODPA layers, both with only some nanometres thickness, provided an excellent protection under this environment. Data availability The raw/processed data required to reproduce these findings cannot be shared at this time as the data also forms part of an ongoing study.

The initial steps of Cu2O sulphidation to Cu2S have been studied using plane-wave density functional theory at the PBE-D3+U level of sophistication. Surface adsorption and dissociation of H2S and H2O, as well as the replacement reaction of lattice oxygen with sulphur, have been investigated for the most stable (111) and (100) surface facets under oxygen-lean conditions. We find that the (100) surface is more susceptible to sulphidation than the (111) surface, promoting both H2S adsorption, dissociation and the continued oxygen–sulphur replacement. The results presented in this proceeding bridge previous results from high-vacuum experiments on ideal surface to more realistic corrosion conditions and set the grounds for future mechanistic studies. Potential implications on the long-term final disposal of spent nuclear fuel are discussed.This paper is part of a supplement on the 6th International Workshop on Long-Term Prediction of Corrosion Damage in Nuclear Waste Systems.

The influence of the composition of stainless steels on atmospheric corrosion resistance in a marine environment in Dubai was investigated after 2 y and 4 y of exposure. Different stainless steel g...

Comments on the paper "Copper in ultrapure water, a scientific issue under debate" by M. Ottosson, M. Boman, P. Berastegui, Y. Andersson, M. Hahlin, M. Korvela, and R. Berger

This work is a further step to develop a finite element model to simulate localized corrosion of aluminum alloys driven by micro-galvanic effects. The focus herein is to explore the effect of density (porosity and tortuosity) of Al(OH)3 precipitates generated both on the electrode surface and in the liquid phase. Two coupled processes are identified and discussed, both influencing the local pH: the Al3+ dissolution from the electrode surface, and the steric hindrance effects on mass transport of species between the bulk solution and the anolyte next to the corroding surface. With the densest precipitate investigated, Al3+ dissolution is more effectively blocked and the mass transport largely hindered of Al3+ ions leaving the electrode surface. With increasing porosity of the precipitate, Al3+ dissolution is enhanced, also the mass transport of species in the electrolyte. The most severe localized acidification inside the occluded volume occurs when the density, namely ascribed by porosity, of precipitate is at an intermediate level with ec = 0.01. In qualitative agreement with experimental observations, this work highlights the importance of corrosion product density on the progress of localized corrosion.

Despite numerous studies on atmospheric corrosion of copper and copper based alloys, the corrosion induced release processes of individual alloy constituents suffer from significant knowledge gaps. This investigation comprises metal release rate measurements of copper, zinc and tin from some copper based alloys including brass (20 wt-%Zn) and bronze (6 wt-%Sn), and their pure alloying metals, copper, zinc and tin. Data have been generated during a 2·5 year urban field exposure in Stockholm, Sweden and parallel laboratory investigations in a specially designed rain chamber using artificial rain. Brass shows significantly lower annual release rates of both copper and zinc compared to pure metal sheets of its alloy constituents. Zinc is preferentially released compared to copper. Dezincification of brass occurs both at field and laboratory conditions, a process influenced by rain characteristics. Alloying with tin does not largely reduce the release rate of copper from bronze compared to pure copper....

Corrosion-induced copper runoff has been monitored for copper sheet, naturally patinated copper and pre-patinated copper, with and without surface treatments, in a marine environment during one yea ...

Data on metal release from stainless steel particles can be used in the assessment and quantification of the potential impact of stainless steel on health and the environment. To elaborate a test method suitable for the study of metal release from particles, the experimental parameters particle loading, agitation and separation of particles from the solution were investigated through exposure of 316L powder particles in two artificial biological media. The results suggest that a small particle loading, bi-linear shaking and centrifugation for separation of particles from the solution give the most reproducible results. They also show that metal release rates are strongly influenced by the physico-chemical properties of the test medium and the effective surface area of particles during exposure.

The atmospheric corrosion of pure copper has been investigated after the deposition of sodium chloride (NaCI) particles and exposure to humid air containing gaseous pollutants. Microgravimetry, Fou ...

The electrochemical behavior and stability of Pt, Ti, TiN, and nano-porous carbon for implantable cardioverter-defibrillator (ICD) electrode application were investigated in a phosphate buffered saline solution. The electrochemical interfacial properties were examined by electrochemical impedance spectroscopy, and the potential and current response during ICD shock pulses were recorded by a digital oscilloscope. Changes in surface composition and structure were investigated using X-ray photoelectron spectroscopy and environmental scanning electron microscopy. When exposed to anodic 700 V shock pulses with duration of 10 ms, only Pt was stable, nano-porous carbon electrode was slightly attacked, whereas Ti and TiN electrodes suffered severe degradation. Upon cathodic shock pulsing, all the materials were stable, but Ti and TiN electrodes with a smooth surface showed evidence of hydrogen adsorption. Porous and rough electrodes produced less gas evolution compared to a smooth surfaces, due to a higher amount of charge transferred through non-Faradaic processes. The reason for this could be higher interfacial capacity due to the large surface area.

The influence of surface treatment of Type 304L (UNS S30403) stainless steel on atmospheric corrosion resistance in urban and marine environments was investigated during 2 months and 7 months of exposure. The surface conditions investigated included as-received, pickled, abraded, and bright-annealed samples. The surfaces were investigated before the exposures, and differences in surface composition, polarization resistance, surface roughness, and wettability were observed between the various surface treatments. During the exposures, all samples decreased in weight. Under the present conditions, the as-received samples showed the best performance in the urban environment, whereas the bright-annealed samples showed the best performance in the marine environment. Different effects of surface treatments on atmospheric corrosion resistance in both environments could be explained best by the resulting differences in passive film composition.

Atomic force microscopy (AFM) and infrared reflection absorption spectroscopy (IRAS) were used for in situ investigations of the initial atmospheric corrosion of bronze. In addition ex situ XPS inv ...

This paper summarizes the results from an extensive field exposure program implemented to study possible seasonal dependencies of copper corrosion rates and runoff rates. Two-year exposures in one ...

In order to fill some major gaps of knowledge for future risk assessments, an interdisciplinary research effort is going on in order to generate relevant zinc runoff rate data from various commercial zinc-based materials, and to explore the relation between the chemical speciation of zinc in runoff water and its ecotoxicity. This study presents runoff rates, based on 1-year exposures of 15 zinc-based materials, which range from 0.07 to 3.5 g/m2 year. When collected immediately after release from the various zinc-based surfaces, chemical speciation modeling of the runoff water suggests that nearly all zinc (>95%) is present as hydrated Zn2+ ions, the most bioavailable speciation form. Evaluation of zinc runoff for possible environmental effects was performed through growth inhibition test with a green alga, Raphidocelis subcapitata. The results show a high correlation between the amount of zinc in the runoff and the environmental effect, suggesting, again, that all zinc is present as hydrated Zn2+. The insight gained aids in predicting actual ecotoxicity effects during environmental fate of zinc, based on chemical speciation of zinc in the runoff.

Wet storage staining is a phenomenon that occurs on both zinc coated and 55% Al–Zn coated steel sheets during shipment or storage in damp conditions. Whereas zinc coated sheets form white corrosion products, 55% Al–Zn coated steel sheets form black corrosion products. The effect of temperature, pH and wet storage on the occurrence of black rust staining of unpassivated Aluzink samples has been investigated in the laboratory in terms of corrosion product formation and composition. A characterization of corrosion products formed has been performed mainly based on scanning electron microscopy with X-ray microanalyses (SEM/EDS) for morphological and quantitative analyses and X-ray diffraction techniques (XRD) for crystalline phase identification. Black rust formation is strongly related to alkaline pH regions and is enhanced by the temperature. All black panels show the presence of Bayerite (Al(OH)3), mainly formed on the aluminum rich dendrite branches and a basic zinc aluminum carbonate (Zn6Al2(OH)16CO3·4H2O) formed in the zinc rich interdendritic alloy regions in contact with air. Blackening of Aluzink surfaces is connected to differences in optical properties of embedded metallic zinc and/or aluminum particles of different shape and size in the corrosion layer.

The GILDES model has been used to perform the first theoretical mechanistic study of the atmospheric corrosion of zinc in a controlled environment. Detailed comparisons are made of model results with laboratory data for short-term (0–1000 min) and long-term (0–680 h) exposures of zinc to SO2, NO2 and O3 at high relative humidities. The agreement of theory and experiment is excellent, indicating that the model has captured the principal processes (especially ligand-promoted dissolution) involved in the corrosion of zinc under these conditions.

Phase identifications of a large number of field exposed sheltered zinc panels have revealed the presence of a number of different corrosion products on zinc. A few of these phases, Zn4SO4(OH)6 · nH2O, Zn5(OH)8Cl2 · H2O, NaZn4Cl(OH)6SO4 · 6H2O and Zn4Cl2(OH)4SO4 · 5H2O, seems to exist as final corrosion products. In order to study the formation of these phases, a field exposure program was implemented in atmospheres yielding different end products. A multi-analytical approach was used for detailed studies from the initial stages to fully developed corrosion films. The present study aims at describing the formation of zinc chlorohydroxysulfate (Zn4Cl2(OH)4SO4 · 5H2O) appearing in urban and industrial atmospheres. It involves the consecutive formation of three phases, namely zinc hydroxycarbonate as the initial phase, zinc hydroxysulfate as the intermediate phase and zinc chlorohydroxysulfate as the final phase.

A field exposure program has been implemented in a rural atmosphere with emphasis on short exposure periods and detailed characterization of layers of corrosion products initially formed on zinc by means of a multi-analytical approach. Surface and bulk analytical studies in combination with deposition and climatic measurements have made it possible to identify a reaction path sequence on sheltered and unsheltered zinc panels, which is consistent with all methods used. It involves the formation of two structurally related phases, namely zinc hydroxycarbonate (Zn 5 (CO 3 ) 2 (OH) 6 ) as the initial phase and zinc hydroxysulfate (Zn 4 SO 4 (OH) 6 · 4H 2 O) as the final phase on sheltered panels and (Zn 5 (CO 3 ) 2 (OH) 6 ) as the final phase on unsheltered panels.

Erratum to : Radiation Induced Corrosion of Copper in Anoxic Aqueous Solution (vol 15, pg C5, 2012)

The surface composition of AISI 304 and 316 stainless steels has been investigated by means of focusing, scanning Auger electron spectroscopy (AES) on locally corroded areas formed upon exposure in chloride media with different acidity and under potentiostatic control. Within 1 minute of dissolution in the active state, there is formed a surface layer, which is markedly enriched in Cr. The existence of this layer is a consequence of the selective dissolution of Fe during initial active dissolution and of alloy components entering the solution in proportions equal to those in the bulk alloy during later stages of active dissolution. In addition, direct evidence is given of the precipitation onto the Cr rich surface region of a few monolayers of Cu2S at higher pH (4 to 8) in the solution and of metallic Cu nodules at lower pH (1 to 2). The localization of these layers within the local attack as well as the localization of a thin Mo containing sulfide layer can be directly related to the chemical dissolution of sulfide inclusions during initiation of crevice corrosion.

The possible surface enrichment of chromium and molybdenum during dissolution of Fe18Cr (110) and Fe18Cr3Mo (110) alloys at constant potentials in the passive region is elucidated by taking into account quantitative information on partial dissolution rates of alloy components as measured by γ-spectrometry and on chemical composition of passivating films as measured by ESCA and AES. Combining results from all methods it is found that chromium under all conditions is enriched in the passivating films. An accumulation of chromium in the alloy is also indicated. For molybdenum, an enrichment in the passive film is observed at − 0.2 V (SCE), whereas in the potential interval 0.1–0.9 V, the molybdenum enrichment as determined by ESCA and AES is hardly significant. On the other hand, γ-spectrometry gives a clear indication of molybdenum enrichment in both potential regions.