The stress corrosion cracking (SCC) susceptibility of type 316 stainless steel in 3.4 per cent NaCl with different concentrations of thiosulphate solution and the inhibiting…
Abstract
The stress corrosion cracking (SCC) susceptibility of type 316 stainless steel in 3.4 per cent NaCl with different concentrations of thiosulphate solution and the inhibiting effect of benzotriazole (BTAH) on SCC were investigated by slow strain rate technique. The addition of BTAH to test solution produces an inhibitive effect on the stress corrosion susceptibility (S). The mode of cracking changed from brittle transgranular to ductile failure at higher concentrations of BTAH. Some electrochemical measurements were obtained to complement the SCC measurements. The results indicated that the inhibitive action of BTAH can be attributed to its adsorption and inhibiting the anodic dissolution of the alloy by the effect of blocking the active sites on the alloy surface.
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A.N. Önal and A.A. Aksüt
The effect of tolyltriazole (TTA) on the corrosion of Al‐Cu, Al‐Si‐Cu and Al‐Cu‐Fe alloys in HCl (pH = 0.5) and NaCl (pH = 6 and 11) respectively at 15○C, 25○C and 35○C has been…
Abstract
The effect of tolyltriazole (TTA) on the corrosion of Al‐Cu, Al‐Si‐Cu and Al‐Cu‐Fe alloys in HCl (pH = 0.5) and NaCl (pH = 6 and 11) respectively at 15○C, 25○C and 35○C has been studied by electrochemical methods. Corrosion potentials, corrosion rates, polarization resistances, inhibition efficiencies and activation energies have been determined. The results have shown that the inhibition efficiencies of TTA changed with pH and temperature. TTA has been adsorbed on the alloys to form Cu(I)‐TTA film. TTA was more efficient at pH = 0.5 and 6 than at pH = 11. Increasing the temperature from 15○C to 35○C decreased the inhibition effect of TTA.
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The corrosion behaviour of copper in dilute HCl solution of pH 1.8‐2, in the absence and presence of different additives of Na2S, was studied by open circuit potential…
Abstract
The corrosion behaviour of copper in dilute HCl solution of pH 1.8‐2, in the absence and presence of different additives of Na2S, was studied by open circuit potential measurement, scanning electron microscopy and polarisation techniques. A complete covering of the surface with the strongly chemisorbed HS− is achieved at ≥10 ppm Na2S concentration. The addition of different concentrations of ethylene diamine (EDA) to HCl of pH 1.8‐2 promoted the dissolution rate, due to an increase in autocatalytic dissolution at the Cu metal surface. However, the synergistic inhibition effect between EDA and Na2S, resulting from the adsorption of HS− on the Cu metal, facilitated the adsorption of EDA.
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Jose-Gonzalo Gonzalez-Rodriguez, Andres Carmona Hernandez, E. Vázquez-Vélez, A. Contreras-Cuevas and Jorge Uruchurtu Chavarin
This paper aims to use an imidazole-based n-ionic Gemini surfactant derived from palm oil to inhibit the sulfide stress corrosion cracking of a supermartensitic stainless steel.
Abstract
Purpose
This paper aims to use an imidazole-based n-ionic Gemini surfactant derived from palm oil to inhibit the sulfide stress corrosion cracking of a supermartensitic stainless steel.
Design/methodology/approach
The slow strain rate testing technique, hydrogen permeation tests and potentiodynamic polarization curves have been used.
Findings
Addition of the inhibitor below the critical micelle concentration (CMC) decreased the corrosion current density (icorr), but not enough to avoid embrittlement due to the entry of hydrogen into the steel. Instead, the addition of the inhibitor close to the CMC decreased the icorr, suppressed the entry of hydrogen and inhibited the sulfide stress cracking of steel. Finally, the addition of inhibitor above the CMC led to a slight increase of icorr and promoted localized corrosion, however, the sulfide stress cracking of steel was inhibited.
Originality/value
A green sulfide stress corrosion cracking inhibitor of a supermartensitic stainless steel has been obtained.
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Weiliang Zhu, Zhaojun Pang, Jiyue Si and Zhonghua Du
This paper aims to study the encounter issues of the Tethered-Space Net Robot System (TSNRS) with non-target objects on orbit during the maneuver, including the collision issues…
Abstract
Purpose
This paper aims to study the encounter issues of the Tethered-Space Net Robot System (TSNRS) with non-target objects on orbit during the maneuver, including the collision issues with small space debris and the obstacle avoidance from large obstacles.
Design/methodology/approach
For the collision of TSNRS with small debris, the available collision model of the tethered net and its limitation is discussed, and the collision detection method is improved. Then the dynamic response of TSNRS is studied and a closed-loop controller is designed. For the obstacle avoidance, the variable enveloping circle of the TSNRS has coupled with the artificial potential field (APF) method. In addition, the APF is improved with a local trajectory correction method to avoid the overbending segment of the trajectory.
Findings
The collision model coupled with the improved collision detection method solves the detection failure and speeds up calculation efficiency by 12 times. Collisions of TSNRS with small debris make the local thread stretch and deforms finally making the net a mess. The boundary of the disturbance is obtained by a series of collision tests, and the designed controller not only achieved the tracking control of the TSNRS but also suppressed the disturbance of the net.
Practical implications
This paper fills the gap in the research on the collision of the tethered net with small debris and makes the collision model more general and efficient by improving the collision detection method. And the coupled obstacle avoidance method makes the process of obstacle avoidance safer and smoother.
Originality/value
The work in this paper provides a reference for the on-orbit application of TSNRS in the active space debris removal mission.
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A.M.S. Abdennabi, A.I. Abdulhadi and S. Abu‐Orabi
Corrosion inhibitors represent the most cost effective and flexible means of controlling internal corrosion associated with oil and gas production. Tests were carried out to…
Abstract
Corrosion inhibitors represent the most cost effective and flexible means of controlling internal corrosion associated with oil and gas production. Tests were carried out to demonstrate the structure/effect relationships which are effective in controlling the inhibition efficiency. To illustrate this approach, the substituent field effect at the paraposition of 1(Benzyl)1‐H‐4,5‐Dibenzoyl‐1,2,3‐ Triazole (BDBT) on corrosion inhibition has been investigated. Mild steel rotating cylinder electrode in acid media was used in conjunction with Tafel polarization technique, AC impedance measurements and continuous linear polarization resistance method. The nitro group was found to cause a considerable decrease in the corrosion inhibition of the parent compound BDBT. Owing to the induction effects of Br on the aromatic ring the bromo derivative has better inhibition protection than the methyl derivative. The corrosion rate profiles obtained from on‐line polarization technique showed that the inhibition capacity of the studied substituents at the para‐position increases as follows: NO2 < CH3 < Br < H.
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A.K. Larios-Galvez, J. Porcayo-Calderon, V.M. Salinas-Bravo, J.G. Chacon-Nava, Jose Gonzalo Gonzalez-Rodriguez and L. Martinez-Gomez
The purpose of this research paper was to investigate the use of methanolic extract of Salvia hispanica (S. hispanica) as a green corrosion inhibitor for bronze in a simulated…
Abstract
Purpose
The purpose of this research paper was to investigate the use of methanolic extract of Salvia hispanica (S. hispanica) as a green corrosion inhibitor for bronze in a simulated acid rain solution.
Design/methodology/approach
Extract of S. hispanica was used as a green corrosion inhibitor for bronze in simulated acid rain solution. Electrochemical techniques such as potentiodynamic polarization curves, electrochemical impedance spectroscopy and electrochemical noise were used. Parameters such as polarization, charge transfer and noise resistance (Rp, Rct and Rn, respectively) were calculated.
Findings
Results showed that the extract acts as a good, anodic type of inhibitor. The inhibitor efficiency increased with increasing its concentration up to 400 ppm, decreasing beyond this concentration. Efficiency also increased with an increase in the immersion time. The inhibition was due to the adsorption of components found in the S. hispanica extract following a Langmuir adsorption isotherm.
Practical implications
S. hispanica extract can be used as a corrosion inhibitor for bronze in acid rain solution.
Originality/value
This study provides new information on the inhibition features of S. hispanica under specific conditions. This eco-friendly inhibitor could find applications to protect bronze exposed to polluted urban atmospheres.
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Hongqiang Fan, Shuying Li, Zhicong Shi, Xuefei LV and Zongchang Zhao
The aim of this paper is to investigate the synergism effect between lanthanum salt (La(NO3)3) and benzotriazole (BTAH) on the corrosion inhibition of commercial brass and to…
Abstract
Purpose
The aim of this paper is to investigate the synergism effect between lanthanum salt (La(NO3)3) and benzotriazole (BTAH) on the corrosion inhibition of commercial brass and to further study the inhibition mechanism.
Design/methodology/approach
Potentiodynamic polarization curves were carried out on bare brass and brass treated with additions of optimum concentration of BTAH, La salt and La salt+BTAH to the basal deposition solutions in 3.5 wt. percent sodium chloride solution. The inhibition mechanism of the composite conversion coatings on brass obtained in optimal deposition techniques were investigated by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), X‐ray diffraction (XRD), and FT‐IR reflection spectra.
Findings
A “Critical La(NO3)3 content” and “Critical BTAH content” were both observed, at which the coatings prepared performs the highest protectiveness, and La(NO3)3 and BTAH had an excellent synergism effect on the corrosion inhibition of brass. The corrosion mechanisms for uncoated and coated brass are different. A remarkable enhancement of the brass's corrosion protection was obtained by the formation of composite conversion coatings consisted of Cu(I)BTA and La coordinate thing except for Cu2O and La2O3, which acted as a barrier avoiding the release of metal ions and inhibited the diffusion of the oxygen.
Originality/value
The results from this paper showed that La(NO3)3 and BTAH could be used together to prepare the novel composited conversion coatings on commercial brass for the good corrosion inhibition.
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Osuani Fyneface Idema, Malik Abdulwahab, Innocent Okechi Arukalam, Ifeyinwa Ekeke, Chigoziri N. Njoku, Chioma Anyiam, Benedict Onyeachu and Emeka Emmanuel Oguzie
Hexavalent chromium has been a benchmark corrosion inhibitor before it was phased out because of its carcinogenic properties. However, because it was phased out, many alternative…
Abstract
Purpose
Hexavalent chromium has been a benchmark corrosion inhibitor before it was phased out because of its carcinogenic properties. However, because it was phased out, many alternative corrosion inhibitors have been introduced but failed to meet the performance of this benchmark inhibitor. Consequently, benzotriazole (BTA) was reported to exhibit chromate-like inhibition performance. Subsequently, Intelli-ion was reported by researchers to exhibit chromate-like performance also with claims of being a unique alternative. This paper aims to review the inhibition performance of these two alternatives. Above all, promotes the unique inhibition performance of Intelli-ion that makes it suitable for application in many sectors.
Design/methodology/approach
In this paper, the corrosion inhibition performances of BTA and Intelli-ion were compared systematically by reviewing some related literatures based on the opinion of the authors.
Findings
Different methodologies for measuring the inhibition performance of BTA showed that it’s an inhibitor of choice. However, the cut edge corrosion performance of Intelli-ion and BTA corrosion inhibitors on galvanized steel of 55% Wt.% Al, 44% Wt.% Zn and 1% Wt.% Si in 5 Wt.% NaCl solution was compared when subjected to scanning vibrating electrode technique (SVET) for 24 h. The results showed faint blue-colored region depicting negative cathodic current density for the Intelli-ion while there was a high-intensity of red-colored region depicting a positive anodic current density for BTA. In other words, the Intelli-ion inhibitor had a better overall cut-edge corrosion inhibition performance than the BTA inhibitor.
Originality/value
This paper compares and further, summarizes the corrosion inhibition performance of Intelli-ion and BTA by evaluating SVET results from the literature. In addition, it serves as an overview and reference for the unique inhibition performance of Intelli-ion when applied in field applications.
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Yao Ding, Zhengtang Luo and Dong Liu
The purpose of this paper is to use Dextrofosfomysin levophenethylamine salt to prepare HEHSPN-(Na)2 (HSPN), a new corrosion inhibitor containing sulfur.
Abstract
Purpose
The purpose of this paper is to use Dextrofosfomysin levophenethylamine salt to prepare HEHSPN-(Na)2 (HSPN), a new corrosion inhibitor containing sulfur.
Design/methodology/approach
The inhibition efficiency for Q235 steel in hydrochloric acid has been evaluated by weight-loss test, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Surface studies were performed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM).
Findings
The results show that inhibition efficiency of HSPN increases with an increase in concentration. Adsorption conforms to Flory–Huggins uniform temperature equation, which is multi-molecular layer adsorption and belongs to physical adsorption.
Originality/value
This paper is intended to be added to the family of papers that deal with green corrosion inhibitors which are highly efficient and can be used in the area of corrosion prevention and control.