Corrosion Monitoring Techniques Research Articles

A Review of Corrosion in Aircraft Structures and Graphene-Based Sensors for Advanced Corrosion Monitoring.

Corrosion is an ever-present phenomena of material deterioration that affects all metal structures. Timely and accurate detection of corrosion is required for structural maintenance and effective management of structural components during their life cycle. The usage of aircraft materials has been primarily driven by the need for lighter, stronger, and more robust metal alloys, rather than mitigation of corrosion. As such, the overall cost of corrosion management and aircraft downtime remains high. To illustrate, $5.67 billion or 23.6% of total sustainment costs was spent on aircraft corrosion management, as well as 14.1% of total NAD for the US Air Force aviation and missiles in the fiscal year of 2018. The ability to detect and monitor corrosion will allow for a more efficient and cost-effective corrosion management strategy, and will therefore, minimize maintenance costs and downtime, and to avoid unexpected failure associated with corrosion. Conventional and commercial efforts in corrosion detection on aircrafts have focused on visual and other field detection approaches which are time- and usage-based rather than condition-based; they are also less effective in cases where the corroded area is inaccessible (e.g., fuel tank) or hidden (rivets). The ability to target and detect specific corrosion by-products associated with the metals/metal alloys (chloride ions, fluoride ions, iron oxides, aluminum chlorides etc.), corrosion environment (pH, wetness, temperature), along with conventional approaches for physical detection of corrosion can provide early corrosion detection as well as enhanced reliability of corrosion detection. The paper summarizes the state-of-art of corrosion sensing and measurement technologies for schedule-based inspection or continuous monitoring of physical, environmental and chemical presence associated with corrosion. The challenges are reviewed with regards to current gaps of corrosion detection and the complex task of corrosion management of an aircraft, with a focused overview of the corrosion factors and corrosion forms that are pertinent to the aviation industry. A comprehensive overview of thin film sensing techniques for corrosion detection and monitoring on aircrafts are being conducted. Particular attention is paid to innovative new materials, especially graphene-derived thin film sensors which rely on their ability to be configured as a conductor, semiconductor, or a functionally sensitive layer that responds to corrosion factors. Several thin film sensors have been detailed in this review as highly suited candidates for detecting corrosion through direct sensing of corrosion by-products in conjunction with the aforementioned physical and environmental corrosion parameters. The ability to print/pattern these thin film materials directly onto specific aircraft components, or deposit them onto rigid and flexible sensor surfaces and interfaces (fibre optics, microelectrode structures) makes them highly suited for corrosion monitoring applications.

Modelling Total-corrosion Behaviour of Reinforcing-steel in 3.5% NaCl-immersed Concrete with Cymbopogon citratus leaf-extract admixture

In this paper, the total-corrosion behaviour of reinforcing-steel embedment in concrete samples, having Cymbopon citratus (C. citratus) leaf-extract admixture, and which were immersed in 3.5% NaCl (a saline/marine simulating environment) is investigated. Electrochemical data of macrocell current measurements were obtained, as an easy to undertake corrosion monitoring technique, from the steel-reinforced concrete specimens, that had been admixed with different concentrations of the C. citratus leaf-extract, before being immersed in the corrosive test-medium. The obtained data were then rendered to prescribed specification from ASTM G109 for the modelling of the total-corrosion prevailing in the reinforcing-steel within the concrete test-samples. Results obtained showed that C. citratus leaf-extract admixture in the concrete samples led to reduction in the total-corrosion of the reinforcing-steel, and, especially, in agreements with previous works where other types of electrochemical monitoring techniques had been employed.

Evaluation of Environmental Factors Related with Atmosphere Corrosivity in Hunan Provice by Atmospheric Corrosion Monitoring Technique

Evaluation of Environmental Factors Related with Atmosphere Corrosivity in Hunan Provice by Atmospheric Corrosion Monitoring Technique

Rebar Corrosion Monitoring and Prevention Techniques

Corrosion is the gradual degradation of the metal by chemical reaction with the environment. The service life of the structure is a major concern that depends on the cost involved in construction, maintenance, and repair works. This paper discusses the corrosion mechanism, factors influencing corrosion, corrosion monitoring techniques, and corrosion protection methods. The monitoring techniques include the Linear polarization method, Active monitoring using sensors, DAQ cards, impedance measurement using chips, etc. Prevention methods include an application of paints with various chemical compositions, cathodic protection inhibitors, the use of fiberreinforced polymer, etc.

A failure prediction model for corrosion in gas transmission pipelines

Transmission pipelines comprise a major part of a gas network, conveying natural gas within jurisdictions, and across international boundaries. In the United States, more than 10,000 failure incidents have been reported in gas transmission pipelines in a 20-year period from 1996 to 2016 leading to a cumulative property damage of more than $748 million. Among different failure sources, corrosion is ranked as the most frequent one, corresponding to approximately a quarter of total failures. Though in-line inspection is counted as the most frequently applied corrosion monitoring technique for oil and gas pipelines, it imposes considerable costs due to the necessity of implementing frequent inspections using smart devices. For this reason, several failure prediction models have been developed to estimate the corrosion failure. However, the majorities of these prediction models rely solely on experimental tests or limited historical records which undermine the extent of their applicability and ignore pipeline environmental and geographical circumstances. The objective of this research is to develop failure prediction models for external corrosion in underground gas transmission pipelines by considering both conventional and environmental/geographical variables. For this objective, multiple regression analysis was performed on the accessible historical data reported for gas transmission pipelines. Two main climate regions of Great Plains and South East in the US were selected, and their corresponding failure prediction models were developed. Such development was based on a step by step procedure analyzing different scenarios. Considering diagnostic measures, null hypothesis and residual analysis, scenario 3 was selected as satisfactory. The validation tests of the developed models present a root mean square error (RMSE) of 0.04 and 0.07 and R-Sq of 0.93 and 0.75, respectively. The results of this research can be applied in maintenance planning of gas transmission pipeline to estimate the critical time in which a pipeline may encounter external corrosion failure, and to accordingly schedule the maintenance activities.

Corrosion Monitoring Assessment on Lithium Nitrate Molten Salts as Thermal Energy Storage Material Applied to CSP Plants

The development of the new generation of concentrated solar power (CSP) plants requires improvements in the thermal energy storage systems, and corrosion produced is one of the main challenges to control since this can affect the costs of the electrical generation. Electrochemical impedance spectroscopy (EIS) has been applied in this research as a corrosion monitoring technique, comparing the results with conventional gravimetric corrosion tests. Gravimetric and electrochemical tests were conducted using AISI 304 stainless steel immersed in a ternary salt mixture composed of 57 wt% KNO3 + 13 wt% NaNO3 + 30 wt% LiNO3 at 550 °C for 1000 h. The corrosion rate obtained using gravimetric and electrochemical tests was 7.8 μm/year and 5.7 μm/year, respectively. According to the results obtained in this research, EIS techniques could be a feasible option to control corrosion in CSP plants and reduce operational risks during the molten salt thermal-electricity conversion.

A Paper‐Based Potentiometric Sensor for Solid Samples: Corrosion Evaluation of Reinforcements Embedded in Concrete Structures as a Case Study

AbstractHerein, we present the first paper‐based device for facing one of the worldwide concerns of the Modern age: the corrosion‐induced deterioration of reinforced concrete. Indeed, the monitoring of corrosion extent in reinforced concrete constructions has been acknowledged as a priority for public safety. In this work, the porosity properties of a paper‐based screen‐printed Ag/AgCl electrode were exploited for realising a smart analytical tool to be directly applied on the solid surface of concrete for the evaluation of corrosion. The analysis was carried out by measuring the electrochemical potential between the metallic reinforcement and the sensor, needing only 70 μL of electrolyte solution. The sensor was firstly tested in the laboratory using reinforced concrete samples and then applied on the real outdoor artwork Music Collection Session by Arman (Milan, Italy). A summary of the main available non‐destructive techniques for corrosion monitoring is reported to provide a critic overview.

A Materials Screening Test of Corrosion Monitoring in LiNO3 Containing Molten Salts as a Thermal Energy Storage Material for CSP Plants

Concentrated solar power (CSP) plants, in the context of thermal energy storage (TES) upgrades, need to provide a timely and effective response to the corrosion process that occurs due to the effect of high temperatures, where one of the main challenges is to control its effect, and thus the costs related to the materials used. Electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) were applied in this study as a corrosion monitoring technique. The electrochemical tests were carried out on the materials AISI304, AISI430, and HR-224 immersed in a mixture of ternary salt composed of 57 wt.% KNO3 + 13 wt.% NaNO3 + 30 wt.% LiNO3 at 550 °C during 100 h of exposure and subsequently compared with solar salt. The test was also carried out on the VM12 alloy in the ternary salt with lithium content at 100 and 1000 h of exposure at 550 °C. The corrosion tests show that the materials conform to a model of protective layer in which the same results were contrasted with the chemical corrosion mechanism of nitrate mixture. According to the results obtained in this research, electrochemical techniques could be an interesting option to control corrosion in CSP plants and reduce operational risks during operation.

Photo-Electrochemical Application of ZnOG Thin Film for in situ Monitoring of Steel Sour Corrosion

Further to traditional corrosion monitoring techniques for rated deteriorations, nowadays modern electrochemical monitoring methods are promising for the control of non-rated damage mechanisms. Considering carbon steel as the most commonly used alloy in the oil and gas industry, there are special grades under NACE MR0175 standard which are immune to sour corrosion. However, according to the industry reports, their immunity can be terminated by upset conditions or on site repairs. This issue will impose either a high operational risk or exorbitant maintenance and inspection costs. Hence, in this paper, a new monitoring technology framework is discussed to lessen a catastrophic failure risk for carbon steel under wet H2S corrosion. In this regard, the application of a developed hybridized ZnO-graphene micro-electrode (ZnOG) with a mix band gap of 1.17 eV is studied. Under hydrogen sulfide attack and when ZnOG hybrids are excited by UV illumination, their photo-electrochemical responses are analyzed. ZnOG hybrids emanate informative impedance signals in a response to the formation of ZnO(1 – x)Sx nano-crystals.

CORROSION OF WELDED CARBON STEEL PIPES IN OIL PRODUCTION FIELDS IN EGYPT

In oil production fields, corrosion of welded carbon steel pipes frequently occurs in areas near welds. Corrosion in other areas may take place at a lower frequency and with a lower detrimental effect. In this paper, a field survey is conducted of eight oil petroleum fields over a period of seven years. Testing of specimens of carbon steel welded joints is carried out under simulated conditions. This study investigates the predominated corrosion damage mechanisms in welded carbon steel pipes. It examines the critical factors triggering corrosion mechanisms and the techniques for corrosion monitoring and mitigation. Flow-induced corrosion and preferential weld corrosion were found to be the most effective mechanisms compared to pitting and microbiologically induced corrosion. Detrimental factors of corrosion mechanisms include flow rates and changes in process parameters of pH, fluid resistivity, and some anion concentrations. The corrosion mitigation was achieved by increasing the dosage of injected corrosion inhibitors.

Monitoring the Corrosion of Steel in Concrete Exposed to a Marine Environment.

Reinforced concrete structures require continuous monitoring and maintenance to prevent corrosion of the carbon steel reinforcement. In this work, concrete columns with carbon and stainless steel reinforcements were exposed to a real marine environment. In order to monitor the corrosion processes, two types of corrosion probes were embedded in these columns at different height levels. The results from the monitoring of the probes were compared to the actual corrosion damage in the different exposure zones. Electrical resistance (ER) probes and coupled multi-electrodes (CMEs) were shown to be promising methods for long-term corrosion monitoring in concrete. Correlations between the different exposure zones and the corrosion processes of the steel in the concrete were found. Macrocell corrosion properties and the distribution of the separated anodic/cathodic places on the steel in chloride-contaminated concrete were addressed as two of the key issues for understanding the corrosion mechanisms in such environments. The specific advantages and limitations of the tested measuring techniques for long-term corrosion monitoring were also indicated. The results of the measurements and the corrosion damage evaluation clearly confirmed that the tested stainless steels (AISI 304 and AISI 304L) in a chloride-contaminated environment behave significantly better than ordinary carbon steel, with corrosion rates from 110× to 9500× lower in the most severe (tidal) exposure conditions.

Acoustic Emission Technique as a Corrosion Monitoring Technique

Acoustic Emission Technique as a Corrosion Monitoring Technique

Synergistic Effect of Trisodium citrate (TSC) on the Inhibition Efficiency of Sargassum swartzii (SS) -Zn2+ System on Mild Steel in Aqueous Environment

The aquatic plant kingdom is a treasure of potential bioactive compounds. Aquatic plants contain some organic compounds that provide definite physiological actions on the human body. In the present study deals with the synergistic effect of Trisodium citrate (TSC)on the inhibition efficiency of methanolic extract of Sargassum swartzii (SS) and Zn2+ system on mild steel in aqueous environment. The corrosion monitoring techniques adopted in the study were weight-loss methods, electrochemical measurements, FT-IR and surface morphological techniques namely SEM and EDX. It has proved the formulation consisting of 100 ppm of Zn2+, 120 ppm of SS and 100 ppm of TSC has 95.77% IE. The high performance of SS - Zn 2+- TSC system could be due to synergistic effect that covers a wide surface coverage area on the metal surface and thus retarding the corrosion. Polarization study reveals that this formulation functions as a mixed inhibitor. AC impedance spectra suggest the presence of protective film on the metal surface. FT-IR spectra reveals that the protective film consists of Fe2+-SS complex, Fe2+-TSC complex and Zn (OH)2. SEM and EDX provide a pictorial representation on the nature of surface film in the absence and presence of inhibitors. Thus, it concluded that Sargassum swartzii - Zn 2+- TSC inhibitor system acted as a good inhibitor in aqueous medium.

Inhibition of erosion corrosion of pipework steel in descaling solution using 5-hydroxytryptamine-based additives: Empirical and computational studies

Mildly HCl (5%) used in formulating acid wash and descaling solution in the oilfield corrodes steel pipework especially at elevated temperatures. 5-Hydroxytryptamine (5-HTM) was tested as alternative non-toxic and eco-friendly anticorrosion additive for protection of steel in 5% HCl at different temperatures. Experimental corrosion monitoring techniques, quantum chemical calculations and molecular dynamics simulations were employed to probe corrosion inhibition, adsorption phenomenon and binding characteristics of 5-HTM to steel surface. It was observed that 5-HTM acts as mixed type inhibitor with domino effect on anodic half reaction. Addition of 5-HTM decreases corrosion current and double layer capacitance but increases charge transfer and polarization resistances. Kinetic, thermodynamic and adsorption parameters were determined and used to further explain the interaction of 5-HTM species with X80 steel surface species. Frontier molecular orbitals energies, ELUMO and EHOMO values reveal high and low electron density sites. At the atomic and molecular levels, interaction and binding energies and mechanism are predicted based on results of geometry optimization, quantum chemical calculations and molecular dynamics (MD) simulations. Some N, O and CC sites in 5-HTM are predicted as active adsorption sites from FTIR, EDS analyses and MD simulations while surface morphology is screened by SEM.

Simplified approach to performance evaluation of selected organic compounds for corrosion inhibitor application in petrochemical plants

Corrosion inhibitors have been researched into, studied and applied in numerous industries worldwide to mitigate the electrochemical deterioration of carbon steels in contact with aggressive medium. Effective and sustainable application of corrosion inhibitors in the oil and gas industry necessitates compatibility with the corrosive environment, non-toxicity and must be economical. Corrosion coupon measurement is the oldest and most widely used corrosion monitoring technique. The traditional approach to evaluate the viability of corrosion inhibitor focuses on inhibitor efficiency. Prevailing industry conditions shows this factor alone is insufficient for evaluation of organic chemical inhibitor compounds. This manuscript focuses on the importance and effect of inhibitor concentration, exposure time and Gibbs free energy in evaluating inhibitor performance and on the selection and suitability of organic chemical compounds for corrosion inhibitors.

Analyses of the Gravimetric and Electrochemical Effects of C16H13N3O3 on Mild Steel Corrosion in 0.5 M H2SO4

This study analyzed the gravimetric and electrochemical effects of C16H13N3O3 (methyl-5-benzoyl-2-benzimidazole carbamate: Mebendazole) on mild steel corrosion in 0.5 M H2SO4, for gaining insights on correlation and significance of differences between the two corrosion-monitoring techniques. For the gravimetric method, weight loss of mild steel specimens immersed in different C16H13N3O3 concentrations mixed in the 0.5 M H2SO4 were obtained for corrosion rates and inhibition efficiencies estimations. For the electrochemical approach, mild steel samples were subjected to potentiodynamic polarization experiments in the different C16H13N3O3 concentrations in 0.5 M H2SO4 that were employed for the gravimetric technique for obtaining instrumental readout of corrosion rate. Results showed that the corrosion rate from the electrochemical experiments exhibited excellent linear correlation (R = 99.91; Nash-Sutcliffe Efficiency = 99.83) with the dataset obtained from the gravimetric corrosion assessments. Both the gravimetric and electrochemical monitoring of mild steel corrosion gave inhibition efficiencies, η > 90%, by the different C16H13N3O3 concentrations for the study. Also, homeoscedastic and heteroscedastic student’s t-test statistics indicated that the differences between the corrosion inhibition efficiencies from the electrochemical and gravimetric techniques were not significant, p-value = 0.9729, but significant for their corrosion rates: 1.52 × 10–6 > p-value > 8.15 × 10–9.

Effects of Cinnamaldehyde as an Eco-Friendly Corrosion Inhibitor on Mild Steel in Aerated NaCl Solutions

This article investigates the impact of cinnamaldehyde as an eco-friendly inhibitor in mitigating corrosion detriment on mild steel in aerated NaCl (3% w/w) using weight loss and potentiodynamic polarization methods. The results indicate moderate inhibition efficiency of cinnamaldehyde reaching around 70% at an optimum level of 0.5 g/L or 500 ppm by establishing an adsorption film on metal surface. Adsorption of the cinnamaldehyde seemed to adhere to the Langmuir isotherm. The corrosion rate decreased with cinnamaldehyde dose up to the optimum level while increased slowly with the medium temperature. The activation energy (Ea) achieved with cinnamaldehyde was found to be lower than that of without cinnamaldehyde. The polarization curves revealed that the inhibitor performs as a mixed-type inhibitor since it diminishes both anodic and cathodic current densities. The calculated inhibition efficiencies using both corrosion monitoring techniques were found to be in good agreement. Additionally, the mild steel surfaces (inhibited and uninhibited) were examined by using SEM–EDX analysis.

Application of Thermal Image Data to Detect Rebar Corrosion in Concrete Structures

Rebar corrosion monitoring techniques have been used in studies involving embedded sensors that can detect changes in the corrosion currents and the polarization resistance of rebars in large structures. Defect detection methods that employ infrared cameras are useful non-destructive testing methods to detect defects in concrete structures. However, the measurement results from these methods would vary depending upon several factors that affect thermography. Because of these reasons, they have not been able to provide sufficient reliability. The goal of this study is to develop a technique that uses infrared cameras to quantitatively measure rebar corrosion rates. To examine the impact of the cover thickness, the experiment variables were set at cover thicknesses of 10, 20, and 30 mm and rebar corrosion ratios of 0%, 1%, 3%, 5%, 7%, and 10%. Each variable was tested and a total of 60 specimens were created (i.e., 54 specimens and 6 preliminary specimens). In this study, corrosion was applied using an electrochemical corrosion method that employs Faraday’s law, i.e., the law of conservation of electric charge. The test results of height, width, and area of temperature distribution curve were analyzed, the height of temperature distribution curve was increased as the heating time was grown. In addition, the area of temperature distribution was varied dependent upon the corrosion rate and cover thickness.

Adina Cordifolia as a corrosion inhibitor – a green approach against mild steel corrosion in 0.5M sulphuric acid medium

PurposeThe purpose of this study is to develop green/natural corrosion inhibitors. Adina cordifolia leaves extract (ACLE) was screened for its corrosion inhibition potential for mild steel (MS) corrosion in 0.5 M H2SO4 medium.Design/methodology/approachAdina cordifolia (AC) leaves were subjected to cold ethanol extraction and concentrated after refluxed with double distilled water. The resultant concentrate was screened for corrosion inhibition studies using sequence of standard corrosion monitoring techniques, namely, gravimetric analysis, electrochemical studies and scanning electron microscopy (SEM).FindingsGravimetric analysis provided evidence that the prepared ACLE showed dose dependent corrosion inhibition; impedance study revealed that the ACLE increases the charge transfer resistance and decreases double layer capacitance while polarization curves indicated that ACLE acts as a mixed-type inhibitor. Further studies over MS surface/test solutions through SEM and Fourier-Transform Infrared spectroscopy evident the formation of ACLE protective film protects MS.Practical implicationsAC’s methanol extract developed in this work can be used as a green corrosion inhibitor over industrial applications.Originality/valueFor the first time, AC leaves were tested as corrosion inhibitors for MS corrosion in 0.5 M H2SO4 medium. The results evidenced that ACLE will be a promising corrosion inhibitor, which could be usable in industries as a green corrosion inhibitor.

Application of Lock-in Amplifier Technique in AC FSM based on AD630

Field Signature Method (FSM) is one of non-intrusive technique for pipeline internal corrosion monitoring, but the commercial FSM systems nowadays are all using DC input which have many shortcomings. In this paper, AC FSM based on AC input has been developed, DC FSM can be replaced by AC FSM with low-frequency. To extract weak signals, the lock-in amplifier based on AD630 has been designed and manufactured, the functions and designed circuits of each part have been proposed. Experimental results show that, the application of lock-in amplifier technique in AC FSM based on AD630 can measure the weak signal from the noise interference effectively, ensuring the accuracy and security at the same time.