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Article
Publication date: 2 March 2012

Behrokh Khoshnevis, Mahdi Yoozbashizadeh and Yong Chen

The purpose of this paper is to investigate the fundamentals of the selective inhibition sintering (SIS) process for fabricating dense metallic parts.

Abstract

Purpose

The purpose of this paper is to investigate the fundamentals of the selective inhibition sintering (SIS) process for fabricating dense metallic parts.

Design/methodology/approach

A SIS‐Metal process based on the microscopic mechanical inhibition is developed. In the process, salt solution is printed in the selected area of each powder layer; the salt re‐crystallizes when water evaporates; salt crystals decompose and grow rapidly prior to sintering; the generated salt particles spread between metal powder particles and prevent the fusing of these particles together, hence inhibiting the sintering process in the affected regions.

Findings

The SIS‐Metal process has numerous advantages. An inhibition of sintering mechanism is established for the future development of the technology. Through chemical and visual analysis using STM the mechanism for the inhibition phenomenon has been identified.

Research limitations/implications

Only bronze powder has been used in the research. Accordingly, the inhibition chemical has been engineered for this material choice. The approach should be feasible for other metals but a proper inhibitor would need to be found for each material choice.

Practical implications

The only limitation envisioned for the process may be the removal after sintering of inhibited sections in hard‐to reach areas using physical means such as scraping or vibration. Chemical removal of such sections should be possible, however.

Originality/value

The paper illustrates a new additive manufacturing technology for metallic parts fabrication.

Article
Publication date: 3 June 2020

Mayya Ziganshina, Sergey Stepin, Sergey Karandashov and Veronika Mendelson

The purpose of this paper is to search for toxic anticorrosive pigments’ substitute in protective coatings is one of the important tasks that the specialists in the field of steel…

Abstract

Purpose

The purpose of this paper is to search for toxic anticorrosive pigments’ substitute in protective coatings is one of the important tasks that the specialists in the field of steel corrosion face.

Design/methodology/approach

One of the ways to solve the problem of metal corrosion is to use complex oxides as pigments, which are characterized as low-toxic compounds and possess the ability to inhibit corrosion.

Findings

In the production of ferrites, it is possible to use production waste as raw material, and that makes it possible to reduce the price of the resulting product and solve environmental problems simultaneously.

Originality/value

Permanent growth of world production is accompanied by the increasing environment corrosiveness, associated with the intensification of air, water basin and soil pollution by industrial waste. This, as well as the continuously increasing operated metal stock, has recently made the tendency of metals’ total loss from corrosion steadily increasing. All of this points to the importance of studying corrosion processes and the systematic and effective fight against metal corrosion.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 November 1989

Metals are attacked by acid” is a commonly‐heard statement that is reasonably correct but rather too sweeping. Some metals are “noble” in that they are not affected by ordinary…

Abstract

Metals are attacked by acid” is a commonly‐heard statement that is reasonably correct but rather too sweeping. Some metals are “noble” in that they are not affected by ordinary, non‐oxidising acids such as hydrochloric acid, and the important noble metals in electronics are copper, silver, gold, palladium and platinum. Many metals are highly reactive, but cover themselves with an inert, self‐repairing layer of oxide when exposed to air. These include tantalum, titanium, stainless steel and aluminium. The oxide films vary widely in their resistance to the hydrochloric acid produced by burning PVC, with tantalum oxide remaining inert under all conditions and titanium oxide being attacked only by boiling, concentrated acid. The chromium oxide inert film on stainless steel, and the alumina film on aluminium react readily, giving the chloride salts of the metals and water:

Details

Anti-Corrosion Methods and Materials, vol. 36 no. 11
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 16 July 2024

Manal El-Zawahry and Hager Gamal

This paper aims to focus on the aqueous extraction of natural dye from haematoxylum campechianum L. bark for finishing the bio-mordant cotton fabrics producing value-added…

Abstract

Purpose

This paper aims to focus on the aqueous extraction of natural dye from haematoxylum campechianum L. bark for finishing the bio-mordant cotton fabrics producing value-added, environment-friendly textile products, for biomedical applications.

Design/methodology/approach

The study focuses on the creation of eco-friendly bio-mordant cotton fabric using gallic acid and gelatin, Al3+ and Fe2+ salts and metal mordant. The optimal pH for extraction, structural characterization and phytochemical analysis of the extracted dye were estimated using UV-visible spectrophotometer, FTIR and qualitative analysis. Variations in electrolyte concentration and pH medium were also considered. The study also examines build-up properties, colorimetric values and fastness characteristics of the colored fabrics.

Findings

All the dyed fabrics exhibit very good to excellent in terms of antimicrobial resistance against S. aureus and C. allbicans.

Practical implications

Pre-mordant cotton fabrics with Fe2+ and a combination of metal and bio-mordant show higher antibacterial resistance against P. aerugionsa. Further, bio-mordant and a combination of both mordant exhibit excellent UV protection and antioxidant activity performance compared to that of undyed fabrics.

Originality/value

This work opens up a huge potential for producing healthy bioactive-colored fabrics used in medical textiles and other usages.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 3 January 2017

Mario Celso Genovez, Luiz Henrique Araujo, Tiago Dinis Pinto and Radim Hrdina

This paper aims to describe the results of lab testing of a newly developed organic inhibitor V-active VCIs. The findings demonstrate that it is possible to eliminate or reduce…

Abstract

Purpose

This paper aims to describe the results of lab testing of a newly developed organic inhibitor V-active VCIs. The findings demonstrate that it is possible to eliminate or reduce the oxidizing action of water, thereby extending the allowable time before painting after hydrojetting, and that the new corrosion inhibitor technology does not interfere with the final quality of paint adhesion.

Design/methodology/approach

Metallic specimens were treated/washed in standard lab condition. A 2 per cent V-active VCI SPH1712 water solution was prepared by diluting the inhibitor in industrial water. Metal sample plates were examined after blasting and after subsequent drying, and were submitted to the paint adhesion tests, cathodic disbondment, total soluble salts, time for formation of flash rust and cyclic corrosion test type III (20 cycles), to evaluate the duration of temporary protection and oxidation prevention and influence on paint adherence.

Findings

Using the V-active VCI proposed technology, it was possible to minimize or eliminate the oxidizing action of the water when the metal is exposed to saline moisture in a closed environment, extending the acceptable time before painting without interfering with the final quality of painting.

Practical implications

The proposed technology allows an increase in the prepared (wet blasted) steel surface during cleaning and preparation, thereby reducing labor and product costs, and reduces water consumption during the preparation process. Practical applications in the shipbuilding, ship maintenance and oil and gas production industries include the preservation of internal tubes and pipes, protection during hydrostatic test processes and cleaning with water and corrosion prevention in diesel tanks contaminated with water.

Originality/value

The intent of this paper is to present the obtained results for a new formulation of organic chemical inhibitors that use water as the application medium. In addition to this property, this group of organic inhibitors maintains the properties of volatile inhibitors. Thus, these compounds are generically known as V-active VCIs.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 4 November 2020

Liliya Frolova and Tatyana Butyrina

The purpose of this paper is to study the patterns of formation of anti-corrosion properties, the development of compositions for pigments by using the method of co-precipitation…

Abstract

Purpose

The purpose of this paper is to study the patterns of formation of anti-corrosion properties, the development of compositions for pigments by using the method of co-precipitation and subsequent heat treatment.

Design/methodology/approach

To obtain co-precipitated hydroxides, aqueous solutions of salts were used. The conditions of synthesis varied according to the following parameters: the nature of the starting salts of metals; and the ratio of metal cations. The anticorrosive activity of the pigments was evaluated by the potentiodynamic method, by comparing the anodic and cathodic polarization curves, and calculated potentials and corrosion currents on the basis of regions of Tafel on curves. Polarization curves were obtained by using Potentiostat/Galvanostat/ZRA Gamry, which connected to the PC, and by using the program Gamry Framework. The measurement results were processed by using the method of simplex-lattice planning. X-ray diffractograms of pigments were recorded on a DRON – 2.0 diffractometer (monochromatic copper radiation with a nickel filter).

Findings

The paper deals with the results of research the dependence of colour characteristics and anticorrosion properties of synthesized compositions on their nature and composition. The presence of aluminium cations leads to the formation of solid solutions of ferrum and aluminium oxyhydroxides.

Originality/value

The main technological properties of pigments are determined by the anionic and cationic composition. Colour characteristics are determined by the cation-chromophore. The anti-corrosive properties of non-calcined pigments are determined to a greater extent by the presence of the formed hydroxyl ions and the composition of the compounds. The greatest protective effect is observed when using double compounds of metals, the dissociation constants of which differ significantly. The protective effect is mainly determined by the slowdown of the anode process. Anions containing aluminium atoms accelerate the corrosion processes.

Details

Pigment & Resin Technology, vol. 50 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 April 1992

Fayza A. Nasr and Hussein I. Abdel Shafy

Investigates the fate and toxicity of continuous feeding withincreasing dosage of heavy metal ions – Cu, Pb, Zn, Cr(VI) –on biogas production from anaerobic digestion of sewage…

Abstract

Investigates the fate and toxicity of continuous feeding with increasing dosage of heavy metal ions – Cu, Pb, Zn, Cr(VI) – on biogas production from anaerobic digestion of sewage sludge. The efficiency of the system (as measured by biogas production and volatile organic matter removal rate) was reduced for about 35 days before returning to a steady state with the toxicity ranking Cu > Cr (VI) > Pb >Zn. Also looks at the effect of two “pulse” doses of the metals.

Details

Environmental Management and Health, vol. 3 no. 4
Type: Research Article
ISSN: 0956-6163

Keywords

Article
Publication date: 27 June 2008

Ayssar Nahlé, Ideisan Abu‐Abdoun and Ibrahim Abdel‐Rahman

The purpose of this paper is to study electrochemically and by weight loss experiments the effect of 4‐vinylbenzyl triphenyl phosphonium chloride on the corrosion inhibition of…

Abstract

Purpose

The purpose of this paper is to study electrochemically and by weight loss experiments the effect of 4‐vinylbenzyl triphenyl phosphonium chloride on the corrosion inhibition of mild steel in 1.0 M HCl solution, which will serve researchers in the field of corrosion.

Design/methodology/approach

Electrochemical and weight loss measurements were carried out on carbon steel specimens in 1.0 M HCl and in 1.0 M HCl containing various concentrations (1.0 × 10−7 to 1.0 × 10−4 M) of the laboratory synthesized 4‐vinylbenzyl triphenyl phosphonium chloride at temperatures ranging from 303 to 343 K.

Findings

4‐vinylbenzyl triphenyl phosphonium chloride was found to be a highly efficient inhibitor for carbon steel in 1.0 M HCl solution, reaching about 99 per cent at the concentration of 1 × 10−4 M at room temperature and about 96 per cent at 303 K, a concentration and temperature considered to be very moderate. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

Practical implications

This inhibitor could have application in industries, where hydrochloric acid solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

Originality/value

This paper is intended to be added to the family of phosphonium salt corrosion inhibitors which are highly efficient and can be employed in the area of corrosion prevention and control.

Details

Anti-Corrosion Methods and Materials, vol. 55 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 March 2005

Kirstie Petherbridge, Peter Evans and David Harrison

Many people believe that Eisler invented the printed circuit board (PCB) in the mid‐1930s, but the origins actually lie nearly before 50 years this. If this is true then who…

1274

Abstract

Many people believe that Eisler invented the printed circuit board (PCB) in the mid‐1930s, but the origins actually lie nearly before 50 years this. If this is true then who invented the PCB? This review offers an alternative view of the history of the PCB including early developments and contributions from the world of art and printing, through innovations in science and engineering to the key developments of the modern electronics industry.

Details

Circuit World, vol. 31 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 11 January 2021

Oxana Ostakh, Elena Uzyakova, Natalya Grechishcheva and Violetta Kusheeva

The purpose of this study is to determine the possibilities to use drill cuttings in soil formation processes on sandy substrates. The ecological and toxicological assessment of…

Abstract

Purpose

The purpose of this study is to determine the possibilities to use drill cuttings in soil formation processes on sandy substrates. The ecological and toxicological assessment of drill cuttings of various genesis and mixtures based on them is applied for the purpose.

Design/methodology/approach

Acute toxicity of mixtures consisting of various drill cuttings, sand and peat was estimated using soft wheat seeds (Triticum aestivum) using the eluate method. Subacute toxicity experiments were carried out using creeping trefoil (white clover) seeds (Trifolium repens), rye seeds (Secale cereale), and garden radish seeds (Raphanus sativus L.). Drill cuttings of the West Siberian oil-and-gas basin generated as a result of drilling on clay-polymer drilling fluids can be used as a component of soil-like mixtures in the reclamation of sand fills. Patterns of the selective stimulation of seed growth by components of drilling fluids (xanthate and bentonite) were revealed.

Findings

It was found that the addition of bentonite and xanthan (0.05% by weight of the cuttings each) reduces the suppression of seed growth occasioned salt content by 21.1% and 24.0%, respectively.

Originality/value

Soil degradation and desertification is a serious and widespread problem. The restoration of the fertile layer can be launched by application of the artificial soil-like mixtures based on drill cuttings of a certain origin to the disturbed lands.

Details

Journal of Engineering, Design and Technology , vol. 19 no. 6
Type: Research Article
ISSN: 1726-0531

Keywords

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