Study Of Atmospheric Corrosion Research Articles

Study of atmospheric corrosion of zinc in a tropical marine environment rich in H2S, resulting from the decomposition of Sargassum algae

AbstractThe Martinique island, located in the Caribbean Sea, is subject to the stranding of Sargassum algae, which decompose and release toxic gases, such as hydrogen sulfide or ammonia. This study aims to investigate the atmospheric corrosion of zinc in these conditions. For this purpose, three sites in Martinique more or less impacted by Sargassum algae stranding were selected. Mass loss results after 1‐year exposure range from 1.9 µm for the site least impacted to 45.3 µm for the site most affected by Sargassum algae. This high value proves that the presence of Sargassum algae caused significant zinc degradation. The morphological structures and properties of the corrosion products obtained at the impacted and non‐impacted sites differ significantly. In the absence of Sargassum algae, “classical” corrosion products based on hydrozincite, simonkoleite, gordaite, and zinc hydroxylsulfate are observed. In the area close to the Sargassum seaweed stranding, the presence of elemental sulfur products, zinc hydroxylsulfate, and sphalerite is reported.

Kinetic study of long-term atmospheric corrosion for carbon steel and galvanized steel exposed in Medellín city (Colombia)

La corrosión atmosférica es uno de los fenómenos naturales de mayor impacto en la integridad de las infraestructuras metálicas en todo el mundo y en especial en ambientes tropicales. Sin embargo; la gran mayoría de los estudios de corrosión atmosférica realizados en ambientes naturales no superan los 5 años de exposición; y son más escasos aún los estudios con resultados de 10 o más años. En este estudio se evaluó la cinética de corrosión del acero al carbono y acero galvanizado expuestos en la zona céntrica de Medellín; catalogada como un ambiente de agresividad moderada; con base en resultados obtenidos tras 1; 2; 5; 8 y 11 años de exposición. Para ambos materiales se obtuvo una ecuación cinética de corrosión mediante gráficas Log-Log de la pérdida de masa; de gran utilidad para hacer predicciones a largo plazo del deterioro de estructuras expuestas a la atmósfera. La corrosión del galvanizado fue aproximadamente entre 10 a 17 veces menor que la del acero al carbono.

Predicting System Degradation with a Guided Neural Network Approach.

Evaluating the physical degradation behavior and estimating the lifetime of engineering systems and structures is crucial to ensure their safe and reliable operation. However, measuring lifetime through actual operating conditions can be a difficult and slow process. While valuable and quick in measuring lifetimes, accelerated life testing is often oversimplified and does not provide accurate simulations of the exact operating environment. This paper proposes a data-driven framework for time-efficient modeling of field degradation using sensor measurements from short-term actual operating conditions degradation tests. The framework consists of two neural networks: a physics discovery neural network and a predictive neural network. The former models the underlying physics of degradation, while the latter makes probabilistic predictions for degradation intensity. The physics discovery neural network guides the predictive neural network for better life estimations. The proposed framework addresses two main challenges associated with applying neural networks for lifetime estimation: incorporating the underlying physics of degradation and requirements for extensive training data. This paper demonstrates the effectiveness of the proposed approach through a case study of atmospheric corrosion of steel test samples in a marine environment. The results show the proposed framework's effectiveness, where the mean absolute error of the predictions is lower by up to 76% compared to a standard neural network. By employing the proposed data-driven framework for lifetime prediction, systems safety and reliability can be evaluated efficiently, and maintenance activities can be optimized.

Graphene coated copper in a one-year atmospheric corrosion and color preserving challenge

A one-year atmospheric corrosion study was conducted to evaluate the performance of transparent single-layer (SLG) and multilayer graphene (MLG) coating as a protective coating on copper substrate against atmospheric corrosion and color changing. Employing the CIE−L*a*b* color space, it was shown that the transparent SLG and MLG coatings can maintain the pure color of copper before exposure to the atmosphere. However, after 15 days the color change (∆E) in the SLG-coated copper (SLG/Cu) was found to be more than that in the bare copper. A scanning Kelvin probe (SKP) was used to measure the surface potential as well as corrosion behavior. The observed decrease of average surface Volta potential of SLG/Cu, from -312 mV to -830 mV, was supposed to be caused by corrosion and electron transfer during galvanic cell formation. Further examinations by Raman spectroscopy, OM, and AFM measurements were logically correlated with those from SKP. Moreover, it was revealed that the surface voltaic potential for MLG-coated copper (MLG/Cu) remains constant along one-year atmospheric exposure. The presented results strongly prove that the MLG coating could be considered an anti-corrosion coating that can fully preserve the color of copper metal after exposure to the environment for at least a year.

Influence of Exposure Conditions and Particulate Deposition on Anodized Aluminum Corrosion

Anodizing is commonly used for corrosion protection of aluminum and its alloys in the construction industry. The anodic aluminum oxide (AAO) coating has a high ability to prevent the development of extensive pitting corrosion in aluminum substrates, particularly in marine sites, as was observed during a 10-year atmospheric corrosion study carried out in several marine and industrial sites. However, this study also evidenced that this coating can be highly affected by the deposition of particulate material in industrial polluted environments, sometimes in unexpected ways. This study presents information on the atmospheric corrosion of anodized aluminum exposed at two different chemical industrial complexes: a fertilizer production plant and a pulp and paper mill. Visual assessment of surface changes, pitting depth and mass variation with exposure were determined to quantify the degradation suffered. Additionally, SEM/EDS analyses were carried out on the exposed surfaces. Based on the results obtained, the role played by the deposition of airborne particles present in the two environments with respect to the type and level of damage observed is discussed. Deposits of roasted pyrite ash and phosphates or of wood chips and lime particles enhanced pitting corrosion or caused dissolution of the AAO coating.

Initial atmospheric corrosion studies of copper from macroscale to nanoscale in a simulated indoor atmospheric environment

Corrosion effects on copper exposed in a humid atmosphere with formic acid (mimicking indoor corrosion) have been explored through successive increase in surface lateral resolution from macroscale (IRRAS, GIXRD) over microscale (LOM, SEM, IR microscopy) to nanoscale (Nano-FTIR, FIB/SEM/EDS). Initial more uniform growth of Cu2O is followed by more varying topography and thickness until local removal of Cu2O enables the aqueous adlayer to react with the copper substrate. Local formation of Cu(OH)(HCOO) and adjacent Cu2O provide microscopic and spectroscopic evidence of corrosion cells. Nano-FTIR shows that the density of Cu(OH)(HCOO) nuclei, but not their size, increases with exposure time.

Measuring Aerosol Chlorides for Atmospheric Corrosion Studies in Cold Alaskan Climate

Atmospheric corrosion is a complex process, which involves chemical, electrochemical, and physical changes to the metal exposed. Atmospheric corrosion occurs when a metal surface is under a thin layer of moisture, but not completely immersed, and the metal surface corrodes while exposed to environmental factors. Atmospheric corrosion of metal alloys in cold environments is assumed to be negligible and limited corrosion data are available in cold climates. However, studies in the Arctic and Antarctic regions have shown significant corrosion damages when exposed to cold conditions. The rate of atmospheric corrosion on various alloys is affected by environmental parameters that include temperature, rainfall, humidity, chloride-ion deposition rate, and time of wetness (TOW). Two important factors that affect atmospheric corrosion rates are aerosol chlorides and TOW. The main goal of this research is to monitor and measure the aerosols chlorides in the atmosphere, measure TOW and correlate the degradation of carbon steel alloys that are widely used in land, sea, and aerospace transportation, the oil and gas, fisheries, and mining applications. The main objectives achieved are design of Combined Chloride and Corrosion Portable Racks (C3PR) and deployment of C3PR racks in four different Alaskan environments. Chloride deposition rate measured using ASTM standards for three different exposure periods along with TOW, ambient temperature and RH data are correlated to the atmospheric corrosion rate of carbon steel to understand the underlying atmospheric corrosion mechanisms. The results from this research work will give a better understanding on the atmospheric corrosion studies in cold arctic/sub-arctic environment and lead to more externally funded projects.

Estimation and mapping of the contribution of nitric acid to atmospheric corrosion of zinc

BACKGROUND AND OBJECTIVES: Atmospheric zinc corrosion in the Mexico City Metropolitan area has long been attributed mainly to the effect of pollutants such as sulfur dipxide. There are changes in the urban atmosphere's chemical composition due to the implementation of air quality policies focused on reducing the emission of sulfur dipxide and other pollutants. This study's objectives were to estimate and map the contribution of nitric acid on zinc's atmospheric corrosion processMETHODS: The impact of nitric acid on zinc is feasible to estimate using a function for a multi-pollutant situation. This function contemplates the sum of two contributions: one of nitric acid and another that includes sulfuric acid and climatic parameters. The multi-pollutant function is suitable to apply in areas without the strong influence of chlorides and tropical and subtropical climates, comparable to the Mexico City Metropolitan area.FINDINGS: The results showed that spatial and temporal estimation of corrosion rates in grams per square meter of zinc was made for 2015-2019, using data modeling in a geographic information system. The maps of corrosion rates allowed us to visualize that, in general, the southwest zone has the most significant effects and that the lowest corrosion rates were presented in 2019 as an outcome of the implementation of air quality programs. Furthermore, a contribution of nitric acid up to 32% to the zinc corrosion rate was estimated.CONCLUSION: The construction of corrosion rate maps provides a spatial and temporal estimate that allows visualizing areas where zinc materials are at risk corrosion due to the dispersion of atmospheric pollutants and climatic parameters. Likewise, it can represent a decision-making tool for the implementation of atmospheric corrosion studies of materials.

Effects of temperature on acceleration and simulation of indoor corrosion test of Q235 carbon steel

PurposeThe purpose of this paper is to study the influence of temperature on the acceleration and simulation of indoor corrosion tests and the corrosion behavior of Q235 carbon steel.Design/methodology/approachThe indoor corrosion test was carried out by continuous salt spray in a salt spray chamber. Weight loss analysis, X-ray diffraction, cannon 1500 D, scanning electron microscopy and electrochemical techniques are used to analyze the results.FindingsIt was found that thickness loss of Q235 carbon steel increases with higher temperature and it can reach 0.095 mm at 50°C. Compared with the Xisha exposure test, the acceleration rate can achieve 230 times. This phenomenon indicates that decreasing the experimental temperature is beneficial to the anti-corrosion of the Q235 carbon steel. It is fascinating to find that acceleration and simulation increase with temperature simultaneously, which shows that β-FeOOH promotes the corrosion rate and α-FeOOH provides high simulation. Meanwhile, electrochemical impedance spectroscopy indicates that the resistance of the rust layer improves with temperature.Practical implicationsThrough the study, the authors found that with the increase of temperature, the acceleration and simulation of indoor corrosion test improved, corrosion products and kinetics are the same as those in outdoor exposure test, and which means that the laboratory can achieve the long-term corrosion degree of outdoor exposure in a short time, and the similarity with outdoor exposure is high. This helps to the study of marine atmospheric corrosion, and indoor accelerated corrosion tests can largely eliminate regional differences by adjusting some environmental factors, and lay a foundation for marine atmospheric corrosion.Originality/valueThe effects of temperature on the acceleration and simulation of indoor corrosion tests are discussed. Through laboratory experiments, the long-term service life of Q235 carbon in the Xisha marine atmosphere can be predicted effectively.

A Field Study of Atmospheric Corrosion of Carbon Steel after Short Exposure in Pelabuhan Ratu, West Java Province, Indonesia

The investigation of atmospheric corrosion of mild carbon steel as representative of offshore infrastructure has been carried out in the marine tropical of Pelabuhan Ratu, West Java, Indonesia. They are exposed up to 76 days of periods, and their corrosion rates are determined according to ASTM G1-03. The surface morphology, the elemental compositions and compounds were observed using a scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The environmental parameters of the test site are monitored during exposure, such as air temperature, relative humidity (RH), airborne salinity and dew temperature. Based on the results, the corrosion rates of steels were 2.79 and 2.8 mpy within the 27 and 76 days exposures, respectively. The presence of chloride deposition on the surface of steel can increase the severity of corrosion. Moreover, the detrimental effect of chloride was observed in rust product, which was covered by an oxygen element. The main phases of rust products present were magnetite (Fe3O4) and hematite (α-Fe2O3.H2O). Several cracks were observed in the rust layer, which tended to exfoliate and lose adherence and protectiveness from further corrosion attack. HIGHLIGHTS The presence of chloride deposition on the surface of steel can increase the severity of corrosion. The severity of corrosion attack mainly depends on the exposure time and some climatic parameters, such as relative humidity (RH), air temperature and chloride airborne. The uniform distribution of the chloride tends to increase the production of ferrous chloride in high RH condition and the aqueous layer deposited on carbon steel. There are two phases on corroded carbon steel such as hematite (α-Fe2O3.H2O) and Magnetite (Fe3O4) after exposure GRAPHICAL ABSTRACT

In-Situ Raman Analysis of Precipitates Formed By Cathodic Polarization for Study of Atmospheric Corrosion in Marine Relevant Environments

Dry storage of spent nuclear fuel (SNF) in the United States exists across the country at independent fuel storage installations sites. At these sites the SNF is stored in stainless steel (SS) canisters equipped with a concrete overpack, where airflow through inlet and outlet vents allow for the passive cooling of the payload. While SS canisters are known for their enhanced corrosion resistance, when placed in a marine and near-marine environment they have shown to be suspectable to localized corrosion. In these environments, sea salt aerosols can adhere to the SS surface and, under certain temperature and relative humidity ranges, deliquescence can occur to form chloride rich brines. Under such exposure conditions, SS is known to undergo passive breakdown and pitting corrosion; thus, can be susceptible to subsequent stress corrosion cracking in the presence of residual stresses.In this study, we explore the relationship between the cathodic polarization and the surface brine present on 304-SS. Corrosion and pitting are a function of both the anodic current demand and the available cathodic current both of which have been shown to be dependent on the environmental exposure conditions. In concentrated salt solutions, certain bulk cations (Mg2+) have a strong thermodynamic driving force to form stable precipitates, such as hydroxides, driven by an increase in pH at the cathode from corrosion reactions, which can block cathodic reduction sites. Using in-situ Raman measurements during a cathodic polarization scan we attempted to identify under which conditions (e.g., potential, pH) precipitates form and what their overall composition is. In MgCl2 rich brines, we observed that the pH of precipitation and the identity of the precipitate were dependent upon the initial MgCl2 concentration, as predicted by thermodynamic modeling. The implications of these measurements demonstrate that the maximum pit size in MgCl2 brine surface environments may be limited as the cathodic reduction sites are blocked by precipitation, perhaps leading to the starvation of the pit and eventual brine dry out.Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. Figure 1. In-situ Raman of SS in 0.189 M MgCl2 brine showing the formation of microcrystalline brucite. Figure 1

Analytic studies of marine atmospheric corrosion based on multiphysics simulation

Because the environment at sea is more severe than inland, the corrosion of hull and ship equipment is extremely serious. It can be said that corrosion is one of the biggest factors affecting the life of ships. The cost of anti-corrosion for ships every year is one third or more of the total maintenance cost. The Marine atmosphere corrosion simulation of Q235 carbon steel is realized by Multiphysics simulation software. Due to the high probability and hazard of electrochemical corrosion in oceanic and atmospheric environment, this paper mainly analyzes electrochemical corrosion behavior and its influencing factors, providing a theoretical basis for monitoring and reducing corrosion hazards. The results show that the corrosion rate of Q235 steel in the oceanic atmosphere is 400 to 600 μm/a, and the corrosion rate is affected by temperature, humidity, limiting current density and other factors.

Application of An Electrical Resistance Sensor-Based Automated Corrosion Monitor in the Study of Atmospheric Corrosion.

An automated corrosion monitor, named the Internet of Things atmospheric corrosion monitor (IoT ACM) has been developed. IoT ACM is based on electrical resistance sensor and enables accurate and continuous measurement of corrosion data of metallic materials. The objective of this research is to study the characteristics of atmospheric corrosion by analyzing the acquired corrosion data from IoT ACM. Employing data processing and data analysis methods to research the acquired corrosion data of steel, the atmospheric corrosion characteristics implied in the corrosion data can be discovered. Comparing the experiment results with the phenomenon of previous laboratory experiment and conclusions of previously published reports, the research results are tested and verified. The experiment results show that the change regulation of atmospheric corrosion data in the actual environment is reasonable and normal. The variation of corrosion depth is obviously influenced by relative humidity, temperature and part of air pollutants. It can be concluded that IoT ACM can be well applied to the conditions of atmospheric corrosion monitoring of metallic materials and the study of atmospheric corrosion by applying IoT ACM is effective and instructive under an actual atmospheric environment.

Simulating study of atmospheric corrosion of Zn-Al alloy coating in industrial zone: Structure and properties of zinc hydroxysulfate rust particles prepared in the presence of Al(III)

In order to simulate the atmospheric corrosion of Zn-Al alloy coating on the steels in industrial zone, zinc hydroxysulfate (Zn4(OH)6(SO4)·nH2O: ZHS) rust was artificially synthesized by hydrolyzing the ZnO particles in a mixture of aqueous ZnSO4 and Al2(SO4)3 solutions and the structure and properties of the products were examined by various means. Then, the atomic ratio XAl = Al(III)/(Zn(II) + Al(III)) in the solution was ranged from 0 to 1.0. Adding Al(III) decreased the solution pH before aging to inhibit rust formation. Added Al(III) was easily incorporated in the particles than Zn(II). Increasing XAl turned the major rust following as hexagonal plate-like ZHS particles → hexagonal plate-like Zn-Al layered double hydroxide (LDH) particles → cubic Al6O5(SO4)4·H2O particles. These rust particles possessed a high adsorption affinity to corrosive CO2 gas. From these results, it can be supposed that atmospheric corrosion of Zn-Al alloy coating on the steels in industrial district produces the dense and compact rust layer composed of plate-like ZHS and/or Zn-Al-LDH particles owing to their preferred orientation to suppress further corrosion of steels.

Atmospheric Corrosion Study to Painted Galvanized Steels Under Maritime, Industrial and Urban Conditions

The atmospheric corrosion, potentially destructive consuming sources and time, is the electrochemical process in which metals are deteriorate by atmospheric factors, that include the effect of climate conditions (periods of wetting and drying, temperature, humidity, rainfall, wind speed and direction, solar and ultraviolet radiation) and the effect of pollution (SO2, NaCl, CO2, NOx and solid particles). Another factor is that atmospheric corrosion involves chemical, electrochemical and physical process in three mater states (solid, liquid and gaseous) and two interfaces (solid/liquid and liquid/atmosphere). In the present study painted galvanized steel sheets were exposed to different environments which include marine, industrial and urban conditions. The aim was study the corrosion behavior of the materials in the different climatic environments. To characterize the corrosion behavior a photographic register was done and an analysis of the layers in cross section with a scanning electron microscope.

In Situ Mass Spectrometric Reaction Monitoring of Atmospheric Corrosion Processes

A set‐up for in situ mass spectrometric reaction monitoring of gas phase mediated reactions is presented. Important constructive parameters for a reaction chamber for the investigation of atmospheric corrosion processes is discussed. The presented cell is especially well suited for atmospheric corrosion studies but it can easily be modified to be applicable in other fields of research as well. The atmospheric corrosion of electrolytically deposited zinc surfaces on steel during wet‐ and dry‐cycles is investigated as a model reaction. Corrosion rates as well as current densities during the first wet‐ and dry cycle are calculated and discussed. Complementary scanning Kelvin probe (SKP) measurements are performed to show the electrochemical changes occurring at the metal/air‐interface throughout the corrosion process. Contact potential difference versus distance measurements performed in advance to determine the maximum measurement distance, which allows investigating rough salt loaded sample surfaces via SKP surface scans.

Atmospheric corrosion study in a harbor located in a tropical island

Atmospheric corrosion level in tropical coastal zones is usually very significant. Corrosion control and preservation of infrastructure in these regions is very important to increase durability. Atmospheric corrosion of carbon steel, copper, galvanized steel, and aluminum was evaluated in a coastal industrial port zone located in a tropical island during 1 year. Samples were exposed at seven outdoor corrosion sites located at different distances from the sea. Main atmospheric pollutants, relative humidity, and air temperature were monitored during the exposure time. The existence of a combination between two of the most aggressive atmosphere types was determined (coastal‐industrial and industrial‐coastal). Changes in RH and temperature influenced significantly the chloride deposition. A new statistical model to explain the influence of time of exposure for all metals tested was developed. A possible antagonist effect between pollutants on corrosion may be possible. Acceleration of corrosion rate vs time is observed in the site close to the shoreline. Significant differences between corrosivity categories determined and those calculated by ISO standard dose response functions were found. The narrow entrance of the harbor with low movement of the inner water causes a decrease in salinity in the port zone.

Corrosion of Binary Mg-Al Alloys

The corrosion behavior of single-phase Mg-Al alloys has been examined using a combination of aqueous, atmospheric and ionic liquid based techniques. Our results show preferential rapid dissolution of Mg along with redistribution and enrichment of the effectively more “noble” Al component. During aqueous free corrosion experiments immediate pH increases were measured at the solid-liquid interface in aqueous chloride. Using inductively coupled plasma mass spectroscopy the oxide/hydroxide chemical dissolution rates were determined to be 0.222 per atomic site/s for Mg2+ and 0.022 per atomic site/s for Al3+ from the elemental alloy components. Atmospheric corrosion studies measured a 60° contact angle decrease during 20 hour free corrosion corresponding to a small 0.04 Jm−2 reduction in the MgO/water interfacial free energy. Rotating disk electrode and ionic liquid dissolution techniques revealed mud cracking, platelet formation and nanowire morphologies that can result from selective dissolution of Mg in single-phase Mg-Al alloys. The evolution of these morphologies is described in terms of a step-flow dissolution mechanism.

(Invited) In Situ Analytical Methods for Atmospheric Corrosion: Recent Advances and Challenges

A foundational challenge inhibiting fundamental study of atmospheric corrosion is the limited ability to directly probe physicochemical processes occurring within electrolytes on surfaces at the micro- and sub-microscale. This talk will overview current and emerging in situ methods for electrochemical and chemical characterization of atmospherically corroding surfaces. Multi-electrode array sensing, microelectrode techniques, optical spectroscopy and other methods will be addressed along with current limitations and future prospects. Some recent advances in these areas will be exemplified through discussion of current research aimed at understanding the thermodynamic and kinetic linkages between evolving electrolytes and electrochemical processes for sodium chloride deposits on copper and aluminum. The role of integrated computational approaches as a means of advancing in-situ methods and providing complimentary physicochemical information will be addressed.

The Results of 45 Years of Atmospheric Corrosion Study in the Czech Republic.

Atmospheric corrosion poses a significant problem with regard to destruction of various materials, especially metals. Observations made over the past decades suggest that the world’s climate is changing. Besides global warming, there are also changes in other parameters. For example, average annual precipitation increased by nearly 10% over the course of the 20th century. In Europe, the most significant change, from the atmospheric corrosion point of view, was an increase in SO2 pollution in the 1970s through the 1980s and a subsequent decrease in this same industrial air pollution and an increase in other types of air pollution, which created a so-called multi-pollutant atmospheric environment. Exposed metals react to such changes immediately, even if corrosion attack started in high corrosive atmospheres. This paper presents a complex evaluation of the effect of air pollution and other environmental parameters and verification of dose/response equations for conditions in the Czech Republic.