Search results

1 – 10 of over 3000
To view the access options for this content please click here
Article
Publication date: 1 June 1993

Inder Singh and Ashis K. Bhattacharjee

The potential measurements in NaCl solutions of varying concentrations carried out separately on galvanised steel and aluminised steel, each coupled galvanically with mild

Abstract

The potential measurements in NaCl solutions of varying concentrations carried out separately on galvanised steel and aluminised steel, each coupled galvanically with mild steel, have shown continuous rise of potential with increase in the concentration of NaCl in both the cases. For the aluminised steelmild steel couple, the protective potential of −760 mV is reached close to the NaCl concentration of 2%, while the potential in the case of galvanised steelmild steel couple has always been above the protective potential, right from the beginning, within the concentration range of NaCl (upto 3%) studied. The current and potential measurements in 0.1% NaCl solution have shown that the resistance of the surface film on aluminised steel grows from 1.037 ×103 ohm to 5.500×103 ohm within the test duration ranging from 20 hours to 100 hours and that on the galvanised steel increases from 0.90×103 ohm to 2.307×103 ohm within the test span ranging from 30 hours to 100 hours. The low current found to have been associated with the aluminised steelmild steel couple is not sufficient to bring the potential at the required protective level for the protection, while about 4 times higher current measured in the galvanised‐mild steel couple helps it in attaining the protective potential.

Details

Anti-Corrosion Methods and Materials, vol. 40 no. 6
Type: Research Article
ISSN: 0003-5599

To view the access options for this content please click here
Article
Publication date: 27 September 2021

Joseph Raj Xavier

The purpose of this study is to use polybenzoxazine (Pbz) functionalized ZrO2 nanoparticles to synthesize polyurethane (PU)-PbZ/ZrO2 nanocomposite. The results derived…

Abstract

Purpose

The purpose of this study is to use polybenzoxazine (Pbz) functionalized ZrO2 nanoparticles to synthesize polyurethane (PU)-PbZ/ZrO2 nanocomposite. The results derived from the electrochemical impedance spectroscopy (EIS) and polarization studies indicated the superior anticorrosive activity of PU-Pbz/ZrO2 nanocomposite coatings compared to those of plain PU coatings. The decreased corrosion current was detected on the scratch of the PU-Pbz/ZrO2 nanocomposite-coated mild steel surface by scanning electrochemical microscopy (SECM) compared to other studied coatings. The superior anticorrosive and mechanical properties of the proposed nanocomposite coatings provide a new horizon in the development of high-performance anticorrosive coatings for various industries.

Design/methodology/approach

The Pbz functionalized ZrO2 nanoparticles were characterized by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) and thermogravimetric analysis (TGA) in terms of the structural, morphological and thermal properties of these coatings. A different formulation of coatings such as PU, PU-Pbz, PU-ZrO2 and PU-Pbz/ZrO2 were prepared and investigated for their corrosion protection performance on mild steel in natural seawater by electrochemical techniques. The surface morphological studies were done by SEM/EDX and XRD analysis.

Findings

The superior anticorrosive property of the proposed nanocomposite coatings provides a new horizon in the development of high-performance anticorrosive coatings for various industries. Addition of Pbz wrapped ZrO2 nanoparticles into the PU coating resulted in the blockage of charge transfer at the metal/electrolyte interface, which reduced the dissolution of mild steel. It was revealed from the SEM/EDX analysis that the formation of the corrosion products at the metal/electrolyte interface behaved as the passive layer which reduced the dissolution of steel.

Originality/value

The inclusion of polybenzoxazine functionalized ZrO2 nanoparticles to the polyurethane coating reinforces the barrier and mechanical properties of PU-Pbz/ZrO2 nanocomposite, which is due to the synergistic effect of ZrO2 and Pbz.

Details

Anti-Corrosion Methods and Materials, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 2 January 2018

Aisha H. Al-Moubaraki

This paper aims to evaluate the inhibitive potential of borage flowers’ aqueous extract (BFAE), Borago officinalis L., against the corrosion of mild steel in 1.0 M phosphoric acid.

Abstract

Purpose

This paper aims to evaluate the inhibitive potential of borage flowers’ aqueous extract (BFAE), Borago officinalis L., against the corrosion of mild steel in 1.0 M phosphoric acid.

Design/methodology/approach

Evaluation was carried out by chemical hydrogen evolution (HE), mass loss (ML) and electrochemical potentiodynamic polarization (PDP) measurements. SEM-EDX analysis also was used to confirm the existence of the adsorbed film.

Findings

It was found that the inhibition efficiency of BFAE increases with the increase in its concentration, but decreases with the increase in temperature. The potentiodynamic polarization curves indicated that BFAE acts as a mixed-type inhibitor with a predominantly anodic action. The adsorption of BFAE on mild steel surface was found to obey Langmuir and thermodynamic-kinetic adsorption isotherms by forming a thin film on the metal surface. SEM-EDX analysis confirms the corrosion inhibition ability of BFEA in 1.0 M H3PO4 by forming a thin film on mild steel surface. In this study, the inhibitive action of BFAE components is discussed on the basis of the physical adsorption mechanism. The same results were obtained for both the freshly prepared extract and the one that kept in a refrigerator for one year.

Originality/value

This paper indicates that BFAE can act as a good inhibitor for the corrosion of mild steel in 1.0 M H3PO4 even after one year of preparation.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 22 June 2012

Fatemeh Baghaei Ravari, Saeed Mohammadi and Athareh Dadgarinezhad

The purpose of this paper is to investigate how to improve the corrosion inhibition behavior of molybdate‐based inhibitors for mild steel, using organic compounds…

Abstract

Purpose

The purpose of this paper is to investigate how to improve the corrosion inhibition behavior of molybdate‐based inhibitors for mild steel, using organic compounds containing a phenyl ring together with nitrite agent. As picrate contains a phenyl ring together with three substituent nitrite anions, it is used as an organic compound. In this study a new molybdate‐based inhibitor was introduced with the composition of 60 ppm molybdate/40 ppm nitrite/20 ppm picrate. Inhibition efficiency of molybdate alone and with nitrite and picrate on the uniform corrosion of mild steel in stimulated cooling water was assessed.

Design/methodology/approach

The inhibition efficiency of molybdate alone and with nitrite and picrate on the uniform corrosion of mild carbon steel in stimulated cooling water (SCW) was assessed by electrochemical techniques such as potentiodynamic polarization, electrochemical impedance (AC impedance) measurements and weight loss determinations at the room temperature. Studies of electron microscopy included scanning electron microscopy (SEM) photography and X‐Ray energy dispersive (EDS) microanalysis were used.

Findings

The results obtained from the polarization and AC impedance curves were in agreement with those from the corrosion weight loss results. The results indicated that the new inhibitor was as effective as molybdate alone, though at one quarter of the concentration range of molybdate, which is economically favorable.

Originality/value

The paper demonstrates improvement in corrosion inhibition of mild steel in SCW via a blend of molybdate, nitrite and picrate as a new anodic inhibitor.

Details

Anti-Corrosion Methods and Materials, vol. 59 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 8 May 2017

Mei Hyie Koay, Mohd Adham Akmal Tukiran, Siti Nur Amalina Mohd Halidi, Mardziah Che Murad, Zuraidah Salleh and Hamid Yusoff

The purpose of this study is to determine the effect of current density on the surface roughness and corrosion performance of electrodeposited Co–Ni–Fe-coated mild steel

Abstract

Purpose

The purpose of this study is to determine the effect of current density on the surface roughness and corrosion performance of electrodeposited Co–Ni–Fe-coated mild steel. Process variables are the key factor in controlling the electrodeposition process. It is important to study the processing parameter to optimize the mechanical and corrosion resistance performance of the coating substrate.

Design/methodology/approach

A low-cost electrodeposition method was used to the synthesize Co–Ni–Fe coating on the mild steel substrate. In the electrodeposition, electrochemistry concept was applied. The temperature of the process was controlled at 50 ± 5°C in an acidic environment. The influence of current density (11, 22 and 33 mA/cm2) and deposition time (15, 20 and 30 min) toward the surface roughness, hardness and corrosion rate was investigated.

Findings

The increases of time deposition and current density have improved the microhardness and corrosion resistance of Co–Ni–Fe-coated mild steel. The Co–Ni–Fe nanoparticles deposited at 30 min and current density of 33 mA/cm2 experienced the smallest surface roughness value (Ra). The same sample also obtained the highest Vickers microhardness of 122.6 HV and the lowest corrosion rate. This may be due to the homogenous and complete protection coating performed on the mild steel.

Practical implications

The findings from the study are important for future application of Co–Ni–Fe on the mild steel parts such as fasteners, car body panels, metal chains, wire ropes, engine parts, bicycle rims, nails and screws and various outdoor uses. The improvement of corrosion resistance using optimum electrodeposition parameters is essential for these applications to prolong the life span of the parts.

Originality/value

A new process which pertains to fabrication of Co–Ni–Fe as a protective coating on mild steel was proposed. The Co–Ni–Fe coating can enhance the corrosion protection and thus prolong the lifespan of the mild steel parts.

Details

Industrial Lubrication and Tribology, vol. 69 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 6 June 2016

Md. Zaved Hossain Khan, Md. Abdul Aziz, Md. Rafiul Hasan and Md. Rashid Al-Mamun

The purpose of this study is to understand the inhibitor behavior of specific drug against mild steel corrosion and their adsorption mechanism on the surface.

Abstract

Purpose

The purpose of this study is to understand the inhibitor behavior of specific drug against mild steel corrosion and their adsorption mechanism on the surface.

Design/methodology/approach

Corrosion rates are influenced by the formation of inhibitor aggregates at the mild steel surface. Detail surface characterizations of mild steel have been studied before and after adsorption of drugs in 1N HCl solution. Scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy were used to examine the effect of drug adsorption on steel surface.

Findings

Scanning electron microscopy analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors. Atomic force microscopy visualization confirmed the formation of protective layer on steel surface, resulting in the decrease in surface roughness with corrosion rates. The nature of metal surface has been analyzed by Fourier transform infrared spectroscopy.

Originality/value

The findings of this study will help us to understand the interaction of specific drugs with mild steel surface and their potential inhibition mechanism.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 30 May 2019

Muazzam Ghous Sohail, Mohammad Salih, Nasser Al Nuaimi and Ramazan Kahraman

The purpose of this paper is to present the results of a two-year long study carried out in order to evaluate the corrosion performance of mild steel bare bars (BB) and…

Abstract

Purpose

The purpose of this paper is to present the results of a two-year long study carried out in order to evaluate the corrosion performance of mild steel bare bars (BB) and epoxy-coated rebar (ECR) in concrete under a simulated harsh environment of chlorides.

Design/methodology/approach

The blocks are subjected to Southern Exposure testing. The electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and Tafel plot are performed to measure the polarization resistance and corrosion current densities of these rebars. Knife-peel test was performed to assess the adhesion between epoxy and underlying steel after two years of exposure.

Findings

Mild steel BB showed a high corrosion current density of 1.24 µA/ cm2 in Tafel plots and a very low polarization resistance of 4.5 kΩ cm2 in LPR technique, whereas very high charge transfer resistance of 1672 and 1675 kΩ cm2 is observed on ECR and ECR with controlled damage (ECRCD), through EIS technique, respectively. EIS is observed to be a suitable tool to detect the defects in epoxy coatings. After two years of immersion in 3.89 percent NaCl solution, the mild steel BB were severely corroded and a considerable weight loss was observed, whereas under heavy chloride attack, ECR showed no deterioration of epoxy coating and neither any corrosion of underlying steel. Results of this study show that the durability of reinforced concrete (RC) structures with respect to corrosion could be enhanced by using ECR, especially in harsh climatic conditions.

Originality/value

The corrosion performance of mild steel and ECR in concrete under a simulating splash zone environment is evaluated. EIS was used to evaluate the health of epoxy and corrosion state of underneath steel rebars. EIS was able to detect the defects in epoxy. The durability of RC structures could be enhanced in harsh climate regions by using ECR.

Details

International Journal of Building Pathology and Adaptation, vol. 37 no. 5
Type: Research Article
ISSN: 2398-4708

Keywords

To view the access options for this content please click here
Article
Publication date: 2 September 2019

Aziz Boutouil, My Rachid Laamari, Ilham Elazhary, Hafid Anane, Abdeslem Ben Tama and Salah-Eddine Stiriba

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely…

Downloads
90

Abstract

Purpose

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely, 1-((1-((2,2,7,7-tetramethyltetrahydro-5H-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methyl)-1H-1,2,3-triazol-4-yl)methyl)-1H-benzo[d]imidazole (TTB) on the corrosion of mild steel in aerated 1 M H2SO4.

Design/methodology/approach

The authors have used weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy, FT-IR studies, scanning electron microscopy analysis and energy dispersive X-ray (EDX) spectroscopy techniques.

Findings

It is found that, in the working range of 298-328 K, the inhibition efficiency of TTB increases with increasing concentration to attain the highest value (92 per cent) at 2.5 × 10−3 M. Both chemisorption and physisorption of TTB take place on the mild steel, resulting in the formation of an inhibiting film. Computational methods point to the imidazole and phenyl ring as the main structural parts responsible of adsorption by electron-donating to the steel surface, while the triazol ring is responsible for the electron accepting. Such strong donating–accepting interactions lead to higher inhibition efficiency of TTB in the aqueous working system.

Originality/value

This work is original with the aim of finding new acid corrosion inhibitors.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

To view the access options for this content please click here
Article
Publication date: 1 September 1967

S. Guruviah and K.S. Rajagopalan

Use of aluminium is coming into vogue in the canning industry. However, the very much higher cost of aluminium than tin plate inhibits the scope for substitution of tin…

Abstract

Use of aluminium is coming into vogue in the canning industry. However, the very much higher cost of aluminium than tin plate inhibits the scope for substitution of tin plate by aluminium. It is therefore of interest to examine whether steel coated with aluminium by any of the known methods is suitable for manufacture of containers for canned products. Aluminium‐coated steel can be considered only if the coating has a more negative potential than the base metal. In a study of the behaviour of sprayed aluminium coatings on mild steel in sodium chloride solutions at different pHs, Ross has pointed out that sprayed aluminium (99.5%) is more negative than steel in neutral and alkaline solutions. In this paper, the potential relationships between steel, steel sprayed with aluminium, and aluminised steel in some organic acids commonly present in food stuffs are discussed.

Details

Anti-Corrosion Methods and Materials, vol. 14 no. 9
Type: Research Article
ISSN: 0003-5599

To view the access options for this content please click here
Article
Publication date: 13 June 2016

Xuhong Qiang, Xu Jiang, Frans Bijlaard and Henk Kolstein

This paper aims to investigate and assess a perspective of combining high-strength-steel endplate with mild-steel beam and column in endplate connections.

Abstract

Purpose

This paper aims to investigate and assess a perspective of combining high-strength-steel endplate with mild-steel beam and column in endplate connections.

Design/methodology/approach

First, experimental tests on high strength steel endplate connections were conducted at fire temperature 550°C and at an ambient temperature for reference.

Findings

The moment-rotation characteristic, rotation capacity and failure mode of high-strength-steel endplate connections in fire and at an ambient temperature were obtained through tests and compared with those of mild-steel endplate connections. Further, the provisions of Eurocode 3 were validated with test results. Moreover, the numerical study was carried out via ABAQUS and verified against the experimental results.

Originality/value

It is found that a thinner high-strength-steel endplate can enhance the connection’s rotation capacity both at an ambient temperature and in fire (which guarantees the safety of an entire structure) and simultaneously achieve almost the same moment resistance with a mild steel endplate connection.

Details

Journal of Structural Fire Engineering, vol. 7 no. 2
Type: Research Article
ISSN: 2040-2317

Keywords

1 – 10 of over 3000