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Article
Publication date: 1 June 1994

A.A. Al‐Suhybani and I.H. Al‐Hwaidi

Introduction The corrosion of iron has been extensively studied in various media. In nitric acid solutions, the corrosion of iron is much faster than in other mineral acids at…

Abstract

Introduction The corrosion of iron has been extensively studied in various media. In nitric acid solutions, the corrosion of iron is much faster than in other mineral acids at comparable concentrations. This is attributed to an autocatalytic process involving some nitrogen oxides, nitrous acid and/or some iron complexes. At high nitric acid concentrations, passivation of iron takes place. The factors affecting the dissolution and the passivation processes are not fully understood. The effect of various inhibitors on the corrosion of iron in acid media has been studied. Thus Ammar et al. have studied the passivation of iron and the effect of some anions, e.g. Br− and I− on the passive film. The effect of amides as inhibitors for iron in nitric acid has been reported by Fouda and Gouda. These authors have found that the corrosion process is controlled by the reaction of amides with HNO3 and not by the surface reaction. The effect of aniline and some aminobenzoic acids on the rate of corrosion of iron has been reported. The present work is aimed at examining the efficiencies of some aniline substitutes as corrosion inhibitors for the corrosion of iron in concentrated nitric acid solution.

Details

Anti-Corrosion Methods and Materials, vol. 41 no. 6
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 7 January 2019

Gopinath Shit and S. Ningshen

High corrosion resistance in different concentrations of nitric acid is essential for structural steels to be used for the aqueous reprocessing of spent nuclear fuels with high…

Abstract

Purpose

High corrosion resistance in different concentrations of nitric acid is essential for structural steels to be used for the aqueous reprocessing of spent nuclear fuels with high plutonium content.

Design/methodology/approach

In the present study, the corrosion resistance of type 304L stainless steel (SS) with modified composition was evaluated in different concentrations of nitric acid using surface analytical techniques, weight loss method and electrochemical measurements.

Findings

Weight loss measurement in boiling 65 per cent nitric acid showed a low corrosion rate value of about 0.2 mm/y (8 mpy) after 240 h exposure. Electrochemical measurements revealed the shift in open circuit potentials as well as corrosion potential toward more noble direction, and the results of electrochemical impedance spectroscopy studies indicated the reduction in the thickness and stability of the passive film with increasing concentration from 6 to 11.5 M nitric acid.

Research limitations/implications

The low corrosion rate observed for this steel is attributed to the higher content of Cr (19 per cent), Ni (10 per cent) and Si (0.3 per cent) and controlled minor alloying elements (S, P, B, C, etc.) in the alloy that contributed to improving the transpassive corrosion resistance and minimizing the intergranular corrosion attack. The X-ray photoelectron spectroscopic analysis revealed the composition of the passive films to be mainly of iron and chromium oxides.

Practical implications

Materials with lower corrosion rates are desirable for applications in nitric acid.

Social implications

The used of nitric acid creates a severe corrosive environment in chemical or aqueous nuclear reprocessing plants, and hence with a modified composition of type 304L SS resulting in minimizing failure of components are desirable for reducing cost and maintenance.

Originality/value

The present paper is an original work carried out by the authors on the corrosion resistance behaviors of composition modified AISI type 304L SS for nitric acid application. The effects of different nitric acid concentrations were compared to provide understanding on in applicability in boiling and high nitric acid concentrations.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 3 June 2022

Chengchang Niu, Shiqing Deng, Yu Yan, Leigang Wu, Ran Tao and Jun Chen

The purpose of this paper is to fill the knowledge gap in the microscopic origin of high corrosion resistance in the passivated 316 L stainless steel.

Abstract

Purpose

The purpose of this paper is to fill the knowledge gap in the microscopic origin of high corrosion resistance in the passivated 316 L stainless steel.

Design/methodology/approach

Here, the pitting corrosion potential of the passivated 316 L stainless steel is measured, as well as the non-passivated one. Using the aberration-corrected scanning transmission electron microscopy, the microstructure of the passive film is unambiguously revealed. Combining the electron energy loss spectroscopy with the X-ray photoelectron spectroscopy, the depth profiling analysis is conducted and the variations in composition from the very surface of the passive film to the internal steel are clarified.

Findings

By optimizing the passivation treatment process, the authors significantly increase the pitting corrosion potential of the passivated 316 L stainless steel by 300 mV, compared with the non-passivated one. The passive film features a unique amorphous multilayer structure. On the basis of the depth profiling analysis, the origin of the high corrosion resistance achieved is unraveled, in which the redistribution of elements in the multilayer passive film, especially the enrichment of Cr in the topmost layer and Ni at the film-metal interface, prevent the oxidization of the inner iron of the steel.

Originality/value

This study advances understanding of the nature of the passive film from a microscopic view, which can be helpful for the further improvement of the corrosion resistance performance.

Graphical Abstract

This study introduces a model for the multilayer structure of passive films that reveals the reconstitution of the passive films after the opportune passivation treatments. Due to the redistribution of elements caused by passivation, the enrichment of Cr in the outer layer and Ni near the film-metal interface leads to enhance corrosion resistance performance.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 August 1968

J.A. von Fraunhofer

Corrosion, the destructive attack upon metals and alloys (and other materials) by their environment, is a common and widespread phenomenon. Although corrosion in domestic life may…

Abstract

Corrosion, the destructive attack upon metals and alloys (and other materials) by their environment, is a common and widespread phenomenon. Although corrosion in domestic life may be restricted to seizure of nuts and bolts or unsightly rust stains, its occurrence in industry, and especially the chemical industry, may have serious economic effects. Corrosion may cause any of the following:

Details

Anti-Corrosion Methods and Materials, vol. 15 no. 8
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 June 1969

R. Drewett

THE METHODS available for the application of chromium coatings are listed in Table 2. Until recently most chromium coatings have been applied either by electrodeposition or…

Abstract

THE METHODS available for the application of chromium coatings are listed in Table 2. Until recently most chromium coatings have been applied either by electrodeposition or chemical vapour deposition. Vacuum and powder‐coating techniques are breaking through in strip‐coating, and electrodeposition has also been investigated extensively since steel, having a thin ‘flash‐coating’ of chromium, can compete successfully with tin‐plate.

Details

Anti-Corrosion Methods and Materials, vol. 16 no. 6
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 6 March 2017

Fan Yi, Wang Qingfeng and Yang Wenxiu

The purpose of this study is to study the pitting caused by Ca-Al-O-S composite inclusions of low-alloy steel in 3 Wt.% NaCl solution and 0.01M NaHSO3 solution.

Abstract

Purpose

The purpose of this study is to study the pitting caused by Ca-Al-O-S composite inclusions of low-alloy steel in 3 Wt.% NaCl solution and 0.01M NaHSO3 solution.

Design/methodology/approach

The corrosion in 0.01M NaHSO3 was much weaker than in 3 Wt.% NaCl 3D display of the pitting formation and development process that has been calculated using scanning electron microscope (SEM) and laser scanning confocal microscopy (LSCM). In addition, a corrosion mechanism of pitting formation by galvanic interaction of composite inclusion and base metal has been proposed.

Findings

Results show that in immersion test, metal base around inclusions was dissolved due to corrosion. Corrosion on the metal base closer to inclusions was more severe.

Originality/value

A corrosion mechanism of pitting formation by galvanic interaction of composite inclusion and base metal has been proposed.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 28 April 2021

Zhaopeng Wang, Yi Wang, Bowei Zhang, Zhan Zhang, Kui Xiao, Junsheng Wu, Qiong Yao, Guojia Ma and Gang Sun

The purpose of this paper is to investigate the influence of the potential of hydrogen (pH) and dissolved oxygen in artificial seawater on the passivation behavior of 316L…

Abstract

Purpose

The purpose of this paper is to investigate the influence of the potential of hydrogen (pH) and dissolved oxygen in artificial seawater on the passivation behavior of 316L stainless steel.

Design/methodology/approach

The corrosion behavior was studied by using electrochemical measurements such as electrochemical impedance spectroscopy and polarization curve. The passive films were characterized with X-ray photoelectron spectroscopy.

Findings

The polarization resistance of the passive film decreases as the pH value drops ascribed to the formation of much more point defects. The donor carrier concentration (ND) in the passive film formed in the deaerated condition is lower than that in aerated conditions. Nevertheless, this phenomenon is the opposite when the pH value is 1 due to the significant decrease of Fe oxides/hydroxides coupled with the stable content of Cr oxides/hydroxides species. In addition, the compositional variation of the passive film also leads to the changes of its semiconductor properties from N-type to bipolar type.

Originality/value

This paper shows the variation of polarization resistance, corrosion potential, passive film composition and semiconductor properties with the pH value and dissolved oxygen. The results can serve as references to the further study on crevice corrosion of 316L in seawater.

Details

Anti-Corrosion Methods and Materials, vol. 68 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 27 January 2021

Alba Gonzalez Alvarez, Peter Ll. Evans, Lawrence Dovgalski and Ira Goldsmith

Chest wall reconstruction of large oncological defects following resection is challenging. Traditional management involves the use of different materials that surgeons creatively…

Abstract

Purpose

Chest wall reconstruction of large oncological defects following resection is challenging. Traditional management involves the use of different materials that surgeons creatively shape intraoperatively to restore the excised anatomy. This is time-consuming, difficult to mould into shape and causes some complications such as dislocation or paradoxical movement. This study aims to present the development and clinical implantation of a novel custom-made three-dimensional (3D) laser melting titanium alloy implant that reconstructs a large chest wall resection and maintains the integrity of the thoracic cage.

Design/methodology/approach

The whole development process of the novel implant is described: design specifications, computed tomography (CT) scan manipulation, 3D computer-assisted design (CAD), rapid prototyping, final manufacture and clinical implantation. A multidisciplinary collaboration in between engineers and surgeons guided the iterative design process.

Findings

The implant provided excellent aesthetical and functional results. The virtual planning and production of the implant prior to surgery reduced surgery time and uncertainty. It also improved safety and accuracy. The implant sited nicely on the patient anatomy after resection following the virtual plan. At six months following implantation, there were no implant-related complications of pain, infection, dislocation or paradoxical movement. This technique offered a fast lead-time for implant production, which is crucial for oncological treatment.

Research limitations/implications

More cases and a long-term follow-up are needed to confirm and quantify the benefits of this procedure; further research is also required to design a solution that better mimics the chest wall biomechanics while preventing implant complications.

Originality/value

The authors present a novel custom thoracic implant that provided a satisfactory reconstruction of a large chest wall defect, developed and implanted within three weeks to address a fast-growing chondrosarcoma. Furthermore, the authors describe its development process in detail as a design guideline, discussing potential improvements and critical design considerations so that this study can be replicated for future cases.

Article
Publication date: 1 December 2004

Xu Chunchun and Hu Gang

Specimens of 304 stainless steel with various martensite contents were prepared by a low temperature (−70°C) elongation method. Optical microscopy and transmission electron…

1271

Abstract

Specimens of 304 stainless steel with various martensite contents were prepared by a low temperature (−70°C) elongation method. Optical microscopy and transmission electron micrography were used to study the phase structure of the samples. A simulated occluded cell (OC) and electrochemical impedance spectroscopy were used to study the chemical and the electrochemical changes within pits on 304 stainless steel containing the different martensite contents. The EIS results showed that the martensite phase decreased not only the solution resistance in pit, but also the polarization resistance value between metal and solution in pit. The composition of the passive film in OC solution was studied by X‐ray photoelectron spectroscopy. It was observed that martensite transformation was a very important factor in changing the composition of the passive film. The martensite phase destroyed the integrality and compactness of the passive film. For these reasons, pit propagation in Type 304 stainless steel was accelerated with increasing martensite content.

Details

Anti-Corrosion Methods and Materials, vol. 51 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 September 1961

ORGANIC INHIBITORS Experimental survey of rust preventives in water—II screening. The methods of testing described in Part I, Idem, Ibid., pp. 246–250, were applied to the…

Abstract

ORGANIC INHIBITORS Experimental survey of rust preventives in water—II screening. The methods of testing described in Part I, Idem, Ibid., pp. 246–250, were applied to the screening of over 400 possible inhibitors, mainly organic, in non‐acid aqueous solutions containing dissolved air, and to supporting polarisation experiments.

Details

Anti-Corrosion Methods and Materials, vol. 8 no. 9
Type: Research Article
ISSN: 0003-5599

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