Corrosion Of Copper Alloys Research Articles

Enhanced corrosion protection of copper alloy in 2.0 M HNO3 solution using expired solo sept, slim-lax and well derm drugs

Three expired drugs, Solo Sept (SS), Slim-lax (SL), and Well Derm (WD), have been tested as corrosion inhibitors for corrosion of copper alloy (C10100) in 2.0 M HNO3 solution. Three experimental methods such as weight loss measurements, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) were applied in this study. These expired drugs function as effective inhibitors, according to the experimental findings. The efficacy of inhibition rises with increasing drug concentration and falls as temperature rises. From PDP, the examined drugs that worked as mixed-type inhibitors. EIS measurements showed a remarkable increase in the charge transfer resistance and decreases in the capacity of the double layer of the corroding copper in 2.0 M HNO3 solution with increasing drug concentration. The inhibition power of these drugs was interpreted in term of its adsorption on the C10100 surface according to Langmuir isotherm. The inverse effect of temperature on drug efficiency as well as the small negative values of ∆G°ads (-20.84, -20.52 and -20.51 kJ/mol) for SS, SL and WD respectively, supports the physical adsorption of drugs on the C10100 surface. All results showed consistency with IE order (SS > SL > WD). The adsorption thermodynamic functions were estimated. The corrosion inhibition performance of SS was confirmed through SEM (scanning electron microscope) and FTIR.

Modeling Copper Alloy Corrosion in Underground Service Line Components

Key TakeawaysIt's important for the water industry to determine which corrosion tests are suitable to evaluate potential alloys for service line components buried underground.Two dezincification tests were effective at correlating to field experience.Electrochemical corrosion tests using “low‐ and high‐corrosive” synthetic soil with neutral pH were not generally effective in predicting field experience.

Microstructure and Chlorine Ion Corrosion Performance in Bronze Earring Relics.

Chlorine ions play an important role in the corrosion of bronzeware. This study employs techniques such as XRD, OM, SEM, EBSD, and electrochemical testing to analyze the microstructure, crystal structure, chemical composition, and corrosion performance of bronze earrings unearthed at the Xindianzi site in Inner Mongolia. The results indicate the presence of work-hardened structures, including twinning and equiaxed crystals, on the earrings' surface. With an increase in chloride ion concentration in NaCl solutions from 10-3 mol/L to 1 mol/L, the corrosion current density of the bronze earrings increased from 2.372 × 10-7 A/cm2 to 9.051 × 10-7 A/cm2, demonstrating that the alloy's corrosion rate escalates with chloride ion concentration. A 3-day immersion test in 0.5% NaCl solution showed the formation of a passivation layer of metal oxides on the earrings' surface. These findings underscore the significance of the impact chloride ions have on the corrosion of copper alloys, suggesting that activating the alloy's reactive responses can accelerate the corrosion process and provide essential insights into the corrosion mechanisms of bronze artifacts in chloride-containing environments.

Condensed Fukui function and experimental evaluation of the corrosion inhibition properties of some antipyrinyl‐imidazotriazole and their derivatives for copper in an acidic environment

AbstractThe effectiveness of synthesized antipyrinyl‐imidazotriazole and its derivatives as inhibitors for the corrosion of copper alloy in 0.5 M H2SO4 solution was tested using weight loss, electrochemical impedance spectroscopy (EIS) and potentiodyanmic polarization techniques. The generated results confirmed that the tested compounds have strong inhibition efficiencies for the protection of the corrosion of copper alloy in 0.5 M H2SO4. Maximum inhibition efficiencies (IEs) evaluated from electrochemical measurements at inhibitor's concentrations of 0.040 g/L were 85% (5‐(4‐Antipyrinyl)‐3H‐imidazo[1,2‐b][1,2,4]triazole), 60% (6‐Antipyrinyl‐imidazo[2,1‐b]thiazole) and 72% (2‐Antipyrinyl‐7‐ethoxy‐imidazo[2,1‐b]benzothiazole). It was observed that the inhibition efficiency was strongly influenced by the flow rate of the solution and was reduced to 79 (5‐(4‐Antipyrinyl)‐3H‐imidazo[1,2‐b][1,2,4]triazole), 60% (6‐Antipyrinyl‐imidazo[2,1‐b]thiazole), and 44% (2‐Antipyrinyl‐7‐ethoxy‐imidazo[2,1‐b]benzothiazole) at an agitation speed of 400 rpm. EI from weight loss was comparable with those from PDP of mixed‐type inhibition style and EIS of diffusion model. The low inhibition efficiency for 6‐Antipyrinyl‐imidazo[2,1‐b]thiazole was significantly enhanced from 60% to 90% through a synergistic effect of 0.0001 M KI. The Temkin and Frumkin isotherms indicate the physical adsorption of inhibitors on copper surface. Condensed Fukui function calculations reveal a common center for electrophilic attacks in the three molecules: the nitrogen in the bridged pyrrole rings (labeled as N11).

Long-term corrosion of copper alloys in the soil: new aspects of corrosion morphology in archaeological vessels from south-western Iran

A group of copper-based objects excavated at Deh Dumen cemetery, in south-western Iran, was studied and analysed to examine the long-term corrosion morphology and mechanism in the soil burial environment. For this purpose, twenty-two samples from twenty-one copper-based vessels were studied and analysed using X-ray diffraction, scanning electron microscopy—energy dispersive X-ray spectroscopy, micro-Raman spectroscopy and metallography techniques. The results of the analyses showed that the majority of vessels are made of tin bronze, along with two arsenical copper samples. The extent of corrosion observed ranges from very thin corrosion crusts to thick crusts and entirely corroded structures. These three identified corrosion morphologies display a multi-layered corrosion stratigraphy as well as the preserved limit of the original surface. The corrosion crusts include internal tin-rich and external copper-rich layers, and the main corrosion mechanism for the formation of multi-layered corrosion crusts is decuprification or selective dissolution of copper during the long-term burial time in a moderately Cl-contaminated soil. The three identified corrosion morphologies are similar to the previously published morphologies, but some clear deviations are apparent and are discussed here.

Evaluation of Chloride Extraction Rates from Copper Compounds Under Subcritical Conditions

ABSTRACT This paper presents a critical review of the reasons behind the initiation of this project to find a more sustainable, cost efficient, and safer form of chloride extraction that would result in stabilisation of archaeological copper and its alloys with tin and zinc. The imperative has become increasingly strident with cutbacks in funding for museum conservation facilities and with the reduction in staff, leaving less time for routine analyses of traditional immersive washing treatments that could take several years to effect. Owing to the faster oxidation and reduction kinetics of copper, compared with tin and zinc ions, the problems of uncontrolled corrosion of copper alloys in a chloride-rich environment have led to unacceptable levels of decay in heritage collection items. This study looked at the chloride extraction rates under subcritical conditions for both primary and secondary chloride-rich mineral species nantokite, clinoatacamite, and atacamite and determined the impact of changing the solution pH from 8 to 10, while also addressing the impact of temperature. The range of temperatures between 130 and 230°C was assessed at 50°C intervals at both levels of acidity of the leaching liquors. For the nantokite treatment, the formation of a cuprite patina which replaced the waxy-grey initial corrosion products was regarded as a bonus. The nature of the patina and changes in surface textures resulting from the treatment are critically reviewed and a series of recommendations for future work are included in the conclusion.

Aesculus hippocastanum seeds extract as eco-friendly corrosion inhibitor for desalination plants: Experimental and theoretical studies

In this work, Aesculus Hippocastanum Seeds (AHS) extract has been used as a sustainability and environmentally corrosion inhibitor to reduce the risk of copper alloy corrosion during the acid cleaning process in desalination plants. This extract contains mostly Quercetin 3,4-diglucoside, Aesculin, escin Ia, escin Ib, isoescin Ia, isoescin Ib, Leucocyanidin, Fraxin, Procyanidin A2, Quercetin, and Kaempferol, according to HPLC analysis. At 100 ppm, the AHS extract showed a 96.1 percent inhibitory efficacy as a corrosion inhibitor. The findings demonstrate that AHS is an effective mixed–type corrosion inhibitor. The AHS extract solution has a greater activation energy value (i.e. 7.32 kJ mol−1) than the blank system (i.e. 15.65 kJ mol−1), indicating a physical adsorption process. Furthermore, the Langmuir adsorption pattern is applied to describe AHS extract adsorption. The electron dispersion in inhibitor compounds was revealed by quantum calculations, revealing their capacity to accept/donate charges from Cu-Ni atoms in vacuum and in water solvation. The extract molecules adsorbed on the copper alloy surface in a nearly flat orientation to acquire maximal surface coverage and contact, according to a molecular dynamics simulation.

Copper-Based Alloys as Anti-Viral High-Touch Surfaces: An Investigation of Kill Efficiency and Mechanism in a Simulated Hospital Environment

The route of transmission of SARS-CoV-2 remains a key concern during the COVID-19 pandemic. One highly important route of transmission is from infected host to fomite surface to a novel host. The purpose of this work is to assess the performance of copper-based alloys as anti-viral materials for high-touch surfaces in terms of virus survivability when exposed to a simulated hospital environment. Upon exposure of such a surface to an electrolyte, such as human perspiration, copper ions and reactive oxygen species are produced via electrochemical reactions, and each are thought to play a role in virus mitigation. The reactions involved, and the fate of copper, depend on alloy composition and the details of surface structure, morphology and the nature of the passive oxide surface film. The oxide film can be severely affected by the environmental conditions to which it is exposed, for example, regular treatment with cleaning products, particularly those containing chlorides. The current work aims to elucidate the mechanism by which the oxide film impacts the efficacy of virus mitigation, though utilization of electrochemical corrosion testing and surface analysis techniques.The current study presents data for the anti-viral performance of Pure Cu and a Cu-30Ni alloy against Human-Coronavirus HuCoV-OC43, a representative strain of a prototypical coronavirus. The study was conducted as a function of periodic exposure to two common cleaning products, namely: (1) bleach and (2) a glutaraldehyde-based solution, for a four-week period. These are compared to surfaces where no cleaning solution was applied. Kill tests were performed by applying a droplet of assay media, carrying the HuCoV-OC43 virus, to the relevant surfaces. Droplet exposure times were systematically increased, up to a maximum of 1 hour, for a kill-rate to be established for each surface. Electrochemical experiments and xps surface analysis, conducted after immersion in artificial perspiration for either 10 minutes or three days, provide information regarding the corrosion rate and kinetics and the nature of the surface oxide film, respectively, for specimens exposed to each of the conditions described.This work will be vital for the immediate selection of specific copper alloys for deployment as high-touch surfaces, and enable future development of alloys further optimized for this function. The presented work will provide an understanding of the corrosion behavior of copper-based alloys in human touch environments, rooted in an understanding of surface chemistry and oxides as well as their potential for mitigating virus transmission. Furthermore, the work aims to demonstrate the application of such metallic coatings for protection against transmission of COVID-19 and future viral diseases as well as revealing the details of copper alloy corrosion mechanisms in a human environment.

Quantitative Understanding of the Environmental Effect on B10 Copper Alloy Corrosion in Seawater

Corrosion in natural seawater is difficult to simulate in a laboratory due to the slow rate and complexity of the corrosion process which involves multiple influential factors. This paper aims to explore the quantitative effect of environmental factors on corrosion process and find the best experimental conditions which represent the actual environment and have the best acceleration effect. A new framework is followed in this paper which consists of three parts: design of experiments, outdoor and laboratory corrosion tests, and corrosion mechanism consistency confirmation. A L6(31 × 22) orthogonal experiment is designed in laboratory to study the effect of temperature, salinity, and dissolved oxygen on marine corrosion behavior of B10 copper alloy. In each test, H2O2 is added in seawater to accelerate the corrosion process. Outdoor exposure tests are also conducted in natural seawater. Results show that the corrosion process in laboratory and outdoor follows the same mechanism, in view of corrosion product and morphology, corrosion kinetics, as well as mechanical properties. With the help of quantitative analysis of the test results, a better acceleration condition can be designed.

Inhibition of copper alloy corrosion using CBG-HCl as a green inhibitor in 0.5 M H2SO4 solution

Inhibition of copper alloy corrosion using CBG-HCl as a green inhibitor in 0.5 M H2SO4 solution

Corrosion of copper alloys in KOH, NaOH, NaCl, and HCl electrolyte solutions and its impact to the mechanical properties

Effects of electrolyte solution (i.e., KOH, NaOH, NaCl, and HCl) with various concentrations (from 0 to 0.71 M) on corrosion and mechanical properties of the copper alloys were investigated. Experimental results showed that the increases in the concentration of electrolytes allowed faster corrosion process. However, too high concentration of electrolytes has no further impacts on the corrosion profile due to the existence of the passivity phenomena on the surface of the material, preventing the material to get more corroded. Acidic (HCl) and salt (NaCl) electrolytes gave more impacts on the corrosion compared to the alkaline solution (i.e., NaOH and KOH) since the acidic and salt ions are able to destroy the formed passivation layer. The correlation of the corrosion rate and the mechanical properties was also presented, in which the increases in the corrosion rate were in line with the decreases in the mechanical properties (i.e., tensile and yield strength). During the corrosion, the atomic structure in the material received attacks from the electrolyte ions, making the structure inside the copper alloys to be less strong and easily fatigued. Understanding the corrosion process and mechanical properties is important for further applications of copper-related alloys in extreme and severe conditions.

Corrosion protection of copper and copper alloys in different corrosive medium using environmentally friendly corrosion inhibitors

AbstractThe corrosion mechanism of copper and copper alloy is reviewed. A number of scientific papers have been investigated to determine the corrosion mechanism and protection techniques of copper and copper alloy corrosion. Results have shown that copper can be corroded in an acidic or an alkaline environment, and oxide formation is the corrosion initiation process. The use of corrosion inhibitors is one of several ways of controlling metal corrosion. There are inorganic (toxic) and organic (green) corrosion inhibitors invented so far. Nowadays, environmental issue is a concern of several scientists in the world. From the results of recent scientific papers, green corrosion inhibitors can be used for copper corrosion protection and they are both economical and environmentally safe. Furthermore, future researches are needed to determine more efficient, environmentally friendly corrosion inhibitors for copper and copper alloys.

Colorimetric/fluorescent dual channel sensitive coating for early detection of copper alloy corrosion

Herein, we developed a straightforward and effective method to prepare epoxy coating for the early stage corrosion-detection of copper alloy. A selective “turn-on” chemosensor derived from rhodamine B for Cu(II), 3′,6′-Bis(diethylamino)-2-[[(2-hydroxyphenyl)methylene]amino]spiro[1H-isoindole-1,9′-[9H]xanthen]-3(2H)-one (RHS), was obtained via a two-step synthesis of acylation and schiff-base reaction. Both the colorimetric and fluorescent signals of the typical 0.5 wt% sensor-doped coating was observed, which showed that the area prior to corrosion was no significant damage. The concentration of RHS could be reduced to 0.14 wt%, after the zinc-based metal–organic framework (MOF) particle, ZIF-8, applied as a nanocontainer in this coating, and the detection sensitivity was better than the coating with bare RHS. This nondestructive strategy successfully realized early-stage corrosion detection for cupronickel in epoxy coating, which could be potentially used in the corrosion detections for copper alloys.

Biocorrosion inhibition of Cu70:Ni30 by Bacillus subtilis strain S1X and Pseudomonas aeruginosa strain ZK biofilms

Microbiologically influenced corrosion (MIC) or biocrorrosion is a cause of huge economic set back for industries around the globe. The present work deals with the study of corrosion of copper alloy (Cu-Ni 70:30) in the presence of bacterial biofilms produced by Bacillus subtilis strain S1X and Pseudomonas aeruginosa strain ZK. MIC was investigated using electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy, and through analytical techniques such as scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and atomic force microscopy (AFM). The Cu-Ni coupons were exposed to bacteria in minimal salt medium supplemented with NaCl for a period of 15 days. AFM and FTIR analysis revealed formation of a thick biofilm on the surface of the Cu alloy in bacterial inoculated systems. The electrochemical results demonstrated a decreased current density and corrosion rate for the systems with bacterial biofilms. These findings were supported by the results of SEM and weight loss studies. The results showed the inhibition of corrosion for Cu-Ni in biotic conditions (with biofilms) as compared with abiotic conditions (without biofilms).

A Study on the Applicability of Corrosion Inhibitor for Outdoor Copper Alloy

Outdoor copper alloy is exposed to the atmospheric environment, accelerating corrosion progress compared with indoor copper alloy. In order to prevent corrosion, the outdoor copper alloy is coated with wax to block external corrosion factors. However, corrosion of the inside of the coating film is highly likely to continue without the internal corrosion prevention treatment. B.T.A, which is used as a copper alloy water-soluble corrosion inhibitor, has a high possibility of being harmful to the human body and is mainly used to treat excavated artifacts. This study had selected the water-soluble corrosion inhibitor, which was easier to use than the existing wax and B.T.A being used in corrosion inhibition treatment for outdoor copper alloy. A comparative study was conducted on B.T.A, which is a water-soluble corrosion inhibitor used on excavated artifacts, and VCIⓇ, RusⓇ, and L-cys, an amino acid corrosion inhibitor, used for tin bronze test pieces. The experimental method was conducted for a certain period of time with the salt, acid, and air pollution affecting the corrosion of outdoor copper alloy. Based on experiment results, it was concluded that the best water - soluble copper alloy corrosion inhibitor in the atmospheric environment is VCIⓇ. and it could be considered to be applied in replacement of B.T.A due to its low harmfulness. In addition, VCIⓇ is judged to serve as a corrosion inhibitor for outdoor copper alloy because it showed the best result even in the outdoor exposure test which is a real atmospheric environment.

Benzimidazole Derivatives as Copper Alloy Corrosion Inhibitors

Benzimidazole Derivatives as Copper Alloy Corrosion Inhibitors

Gold, Silver and Bronze Analysis of Three Fragments of Technical Ceramic from Elsfleth-Hogenkamp, Germany

Two crucible fragments were found during recent excavations in levels dated to the Roman imperial period in Elsfleth-Hogenkamp, a site interpreted to be a beach market located at the junction of the Hunte and Weser Rivers with water access to the North Sea. The crucible fragments were discovered in cultural layers dated to the 2nd-3rd centuries AD in an excavation trench placed near the concentration of metalworking debris, copper-alloy objects and casting waste found during terestrial metaldetecting surveys. Near this concentration in southwest part of the site, a fragment of technical ceramic with copper-alloy corrosion products was found as a surface find. These three pieces of technical ceramic were investigated by optical and scanning electron microscopy and compared with five pottery sherds of local manufacture. Evidence of the casting of gold, silver, bronze and copper was found as well as the importation of high quality technical ceramic. This study focuses on the material and technical aspects of the metallurgical ceramics and the results raise further questions on the meaning and organization of metalworking at the site.

The Effects of Water Flow Rate on Copper Corrosion

This study investigates the effect of water flowrate on the copper alloy corrosion by using a hydrodynamic corrosion test in operating conditions of water flow rate range between 0.05 and 3.5 m/s, the temperature range between 20 and 45 °C. Dissolved oxygen concentration was in the range between 6.1 and 9.2 mg/l. The effects of water properties density, viscosity, and the tube geometric dimensions also considered. Corrosion rate determined by the weight loss calculation method and the tested samples microstructures characterized using FESEM. The results showed that the copper surface layer more affected by water flow at the beginning of turbulent flow condition, while at fully developed turbulent flow condition the surface covered with a fixed oxide layer. Therefore, corrosion found to be at higher rates during the initial stage of the turbulent flow condition, but it reduced at fully developed turbulent flow conditions at higher water velocity. These results indicate that the overall flow rate conditions, which include physical properties of the fluid, hydrodynamic parameters, and the geometric tube dimensions, have the dominant influence on corrosion rate.

Yttrium 3-(4-nitrophenyl)-2-propenoate used as inhibitor against copper alloy corrosion in 0.1 M NaCl solution

Yttrium 3-(4-nitrophenyl)-2-propenoate has been studied as an effective corrosion inhibitor for copper alloy in 0.1M chloride solution. The results show that the surface of copper alloy coupons exposed to solutions containing 0.45mM yttrium 3-(4-nitrophenyl)-2-propenoate had no signs of corrosion attack due to protective film formation, whereas the surface of copper alloy coupons exposed to non-inhibitor and lower concentrations of yttrium 3-(4-nitrophenyl)-2-propenoate containing solutions were severely corroded. A high inhibition performance is attributed to the forming protective inhibiting deposits that slow down the electrochemical corrosion reactions and mitigate corrosion by promoting random distribution of minor anodes.

Study on the corrosion of copper alloy by friction stir surface processing

Purpose This paper aims to investigate the modification of surface of a copper alloy by friction stir surface processing (FSSP). Design/methodology/approach The metallographic condition of the surface modification was observed using microscopy. Electrochemical corrosion tests were carried out on the modified surface and the corroded surface was observed by scanning electron microscopy (SEM). Findings The test results showed that FSSP resulted in refinement of the surface grains of the copper alloy. The degree of refinement was increased with rotation speed and increased in the descending distance of the stirring tool. The corrosion resistance of the modified surface was superior to the base metal except for the surface generated by a rotation speed of 800 rpm and a descending distance 0.1 mm. For the surface modification of the rotation speed of 800 rpm, its corrosion resistance was lower than for the other two rotation speeds. When the rotation speed is specified, the corrosion resistance is improved with increased descending distance. When the descending distance is specified, the corrosion resistance is improved with the rotation speed. Originality/value In this study, it was confirmed that the corrosion resistance of the surface modification was best at the rotation speed 1200 rpm and descending distance 0.2 mm.