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Article
Publication date: 26 August 2014

I.R. Ramos, S.B. Valdez, K.R. Zlatev, W.M Schorr, B.M. Carrillo, M.S. Stoytcheva, I.R. Garcia and M.M. Martinez

– The purpose of this investigation was to develop a digital instrument for the quantitative evaluation of pitting corrosion in metals.

636

Abstract

Purpose

The purpose of this investigation was to develop a digital instrument for the quantitative evaluation of pitting corrosion in metals.

Design/methodology/approach

This investigation comprised two central parts: research, testing and monitoring of the formation of pitting by conventional methods and applying American Society for Testing and Materials (ASTM) Standards, and the development of a virtual instrument based on the LabVIEW 2010 platform.

Findings

The methodology used was suitable for the analysis of pitting on carbon steel and aluminum alloy UNS A96061, used in the aerospace industry.

Practical implications

This technique allows pits to be to localized, measured and quantified on metallic surfaces, for corrosion evaluation in atmospheric and industrial environments.

Originality/value

This combination of conventional and digital methods can assist in corrosion control of pitting in industrial equipment.

Details

Anti-Corrosion Methods and Materials, vol. 61 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 26 June 2009

O.L. Vargas, S.B. Valdez, M.L. Veleva, K.R. Zlatev, W.M. Schorr and G.J. Terrazas

The purpose of this paper is to evaluate the corrosion of silver due to hydrogen sulphide pollutant in indoor conditions at a microelectronics plant located in Mexicali, Baja…

767

Abstract

Purpose

The purpose of this paper is to evaluate the corrosion of silver due to hydrogen sulphide pollutant in indoor conditions at a microelectronics plant located in Mexicali, Baja California, a semi‐arid zone in the northwest of Mexico.

Design/methodology/approach

Silver coupons and silver plated on to copper‐lead frames are exposed in the assembly process building of a microelectronics company during a period of 60 days and also in a sheltered test chamber that simulates indoor conditions with ambient concentrations of atmospheric pollutants, temperature and relative humidity (rH). Other exposures are made in the test chamber to study the corrosion behaviour of silver coupons over a duration of 24 months. The corrosion products were analysed using the Scanning Electron Microscope (SEM) and Energy Dispersive X‐ray Spectroscopy (EDS). Corrosion rates were measured by Quartz Crystal Microbalance (QCM) under laboratory‐controlled conditions.

Findings

The presence of silver sulphide corrosion products, dendrites and whiskers is observed on the exposed samples using SEM and EDS analysis.

Practical implications

The paper is designed to establish whether the company, where the exposure is taking place, constituted an indoor environment with outdoor hydrogen sulphide pollutant in sufficient concentration to induce silver corrosion.

Originality/value

The methodology used in this work can be applied to study the indoor corrosion behaviour of other metals, which will be of interest to the microelectronics industry.

Details

Anti-Corrosion Methods and Materials, vol. 56 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 November 2006

S.B. Valdez, R.K. Zlatev, W.M. Schorr, G.N. Rosas, Ts. Dobrev, M. Monev and I. Krastev

To develop and test a rapid method for evaluation of the corrosion protection (CP) of carbon steel (CS) by vapour corrosion inhibitors (VCI) films.

404

Abstract

Purpose

To develop and test a rapid method for evaluation of the corrosion protection (CP) of carbon steel (CS) by vapour corrosion inhibitors (VCI) films.

Design/methodology/approach

The determination of the CP by VCI on CSs is commonly carried out in a chamber applying neutral salt spray (NSS) and usually it takes many days. The common disadvantage of the various rapid methods created until now is the need of special laboratory equipment making their application complicated and inconvenient for field tests. The method for CP measurement of VCI films on CS described in this study is based on measurement of the height of the anodic peak under galvanostatic condition applied earlier on other types of films and coatings. By means of a calibration plot: peak height (V) vs NSS protection time (s), CP of VCI films on CS specimens expressed in hours NSS is determined in a few seconds without using an NSS chamber. Measurements of CP by VCI films under field conditions are performed applying a hand held tester.

Findings

Two groups of CS UNS G10180 steel specimens with increasing thickness of VCI films were studied – one in an NSS chamber and the second by the application of a corrosion tester. The correlation between the results obtained for the two groups of specimens was found and a calibration plot was made.

Practical implications

Based on this method, a special corrosion tester was developed, able to measure under field conditions as well.

Originality/value

The method subject of the paper is a further development of a galvanostatic method developed by the authors for CP evaluation of chromate films of Zn and Cd coatings. The method was modified according to the properties of VCI films

Details

Anti-Corrosion Methods and Materials, vol. 53 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 13 November 2007

B.G. Lopez, S.B. Valdez, K.R. Zlatev, P.J. Flores, B.M. Carrillo and W.M. Schorr

Aggressive environments that enhance indoor corrosion in industrial plants decrease the yielding of electronic equipment, causing electrical failures. The purpose of the present…

800

Abstract

Purpose

Aggressive environments that enhance indoor corrosion in industrial plants decrease the yielding of electronic equipment, causing electrical failures. The purpose of the present paper is to evaluate corrosion rates in metals used in electronic devices as a function of temperature, humidity and the concentrations of some air pollutants in order to predict the optimal conditions preventing or minimizing corrosion.

Design/methodology/approach

Atmospheric pollutants mainly sulphur oxides, penetrating through small crevices and holes into electronic plants in combination with climatic factors such as humidity and heat, promote corrosion. The corrosion rate of the five most used metals in the electronics industry: carbon steel, copper, nickel, silver, and tin, were studied gravimetrically as a function of variations in humidity, temperature and air pollutant concentrations from 2003 to 2005. The samples were exposed in an instrumented boot to indoor conditions and gravimetric measurements were performed together with measurements of the above‐mentioned parameters. Mathematical simulation applying Math Lab software was carried out as well. The ternary diagrams for pollutants, temperature and relative humidity were applied as a useful tool to correlate these parameters in indoor conditions with the corrosion rate of metals applied in the electronics industry.

Findings

The obtained results have shown that the presence of even small concentrations of air pollutants promoted corrosion processes when time of wetness conditions were reached.

Practical implications

The study was carried out in order to minimize the corrosion losses of the electronic plants situated especially in Mexicali City located on a semi‐desert zone in the Northwest of Mexico.

Originality/value

This paper establishes the relationship of variations of pollutants concentration, temperature and the relative humidity with the corrosion rate of metals in indoor conditions in the electronics industry located in the semi‐arid zone of Mexicali. Design was characterized and simulated using the MathLab software.

Details

Anti-Corrosion Methods and Materials, vol. 54 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 8 November 2011

Gustavo Lopez, Hugo Tiznado, Gerardo Soto Herrera, Wencel De la Cruz, Benjamin Valdez, Miguel Schorr and Zlatev Roumen

The electronics industry has grown over the past 50 years, mostly in developed countries, contributing to their economic progress. Particularly in the Baja California State…

853

Abstract

Purpose

The electronics industry has grown over the past 50 years, mostly in developed countries, contributing to their economic progress. Particularly in the Baja California State located in the northwest of Mexico, these companies have prospered in the industrial parks of Mexicali considered as an arid zone and Ensenada, a port and city on the Pacific Ocean considered as a marine region. In both environments, during winter and summer, the climate impacts on indoor conditions, affecting humidity and temperature, and generating corrosion which decreases the yields of the electronic devices and industrial machines. The purpose of this paper is to investigate the effects of corrosion on electronic devices in these arid and marine environments.

Design/methodology/approach

The paper determines the corrosivity levels inside industrial plants of desertic and coast regions in Mexico, to evaluate the deterioration of electronic metals.

Findings

Relative humidity, temperature, time of wetness, are recorded and related to the corrosion process in arid and marine environments.

Research limitations/implications

Some missing information about air pollution in Ensenada from some Environmental Monitoring Stations was a limitation, and the need to use complex atmospheric techniques.

Originality/value

The paper shows that it is very important to control metallic corrosion generated by climate factors and air pollution in indoor industrial plants: the corrosion of electronic devices and equipments depletes their yield and can lead to loss‐making failures.

Details

Anti-Corrosion Methods and Materials, vol. 58 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 1 October 1999

Jørgen Brandt, Jesper H. Christensen and Zahari Zlatev

Describes a tracer model, DREAM (the Danish Rimpuff and Eulerian Accidental release Model), developed for studying transport, dispersion, and deposition of air pollution caused by…

350

Abstract

Describes a tracer model, DREAM (the Danish Rimpuff and Eulerian Accidental release Model), developed for studying transport, dispersion, and deposition of air pollution caused by a single but strong source. The model is based on a combination of a Lagrangian short‐range puff model and a Eulerian long‐range transport model. It has been run and validated against measurements from the two European Tracer Experiment (ETEX) releases and from the Chernobyl accident. An air pollution forecast system, THOR, is under development, to make forecasts of various air pollutants on a European scale. Some preliminary results are shown. DREAM will be implemented in THOR for calculations of real time predictions of transport, dispersion and deposition of radioactive material from accidental releases (e.g. Chernobyl). Some applications of the DREAM model and examples of model results are described.

Details

Environmental Management and Health, vol. 10 no. 4
Type: Research Article
ISSN: 0956-6163

Keywords

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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…

187

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

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Article
Publication date: 25 May 2010

Lopez Badilla Gustavo, Valdez Salas Benjamin, Schorr Wiener Miguel, Rosas Gonzalez Navor, Tiznado Vazquez Hugo and Soto Herrara Gerardo

The purpose of this paper is to study the indoor corrosion of metals used in the electronics industry, as influenced by climate factors.

497

Abstract

Purpose

The purpose of this paper is to study the indoor corrosion of metals used in the electronics industry, as influenced by climate factors.

Design/methodology/approach

Corrosivity levels inside industrial plants were evaluated to evaluate the deterioration of metals.

Findings

Relative humidity, temperature, and time of wetness are recorded and related to the corrosion process.

Originality/value

Control of climate factors indoors in industrial plants to reduce and control the corrosion process of metals used in the electronics industry.

Details

Anti-Corrosion Methods and Materials, vol. 57 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 5 January 2015

Mário Celso Genovez, Luiz Henrique Araújo, Tiago Dinis Pinto and Radim Hrdina

This work describes test results that were obtained using a newly-developed type of organic inhibitor: V-active VCIs. The findings demonstrate that is possible to eliminate or…

221

Abstract

Purpose

This work describes test results that were obtained using a newly-developed type of organic inhibitor: V-active VCIs. The findings demonstrate that 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 by hydrojet (35000 Psi). It was employed as a 2 per cent V-active VCI SPH 1,712 water solution by dilution of the inhibitor in industrial water. Metal sample plates were examined after blasting and after subsequent drying, and were submitted to the paint adhesion tests, to evaluate the duration of temporary protection, oxidation prevention and influence on the adherence of paint (pull off).

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 the saline moisture in a closed environment, extending the acceptable time before painting without interference in the final quality of painting.

Practical implications

The proposed technology allows to the area of prepared (wet blasted) steel surface to be increased 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 medium as the application method. In addition to this property, this group of organic inhibitors maintains the property of volatile inhibitors. Thus, these compounds are generically known as V-active VCI.

Details

Anti-Corrosion Methods and Materials, vol. 62 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 13 February 2017

Jesper Clement, Viktor Smith, Jordan Zlatev, Kerstin Gidlöf and Joost van de Weijer

The purpose of this paper is to present an experimental study which aims at assessing the potentially misleading effect of graphic elements on food packaging. The authors call…

2405

Abstract

Purpose

The purpose of this paper is to present an experimental study which aims at assessing the potentially misleading effect of graphic elements on food packaging. The authors call these elements potentially misleading elements (PMEs) as they can give customers false expectations. They are either highlighted numerical information (30 per cent fibre, 8 per cent fat, 100 per cent natural […]) or pictorial information with no relation to the product (e.g. images of happy people).

Design/methodology/approach

In a combined decision task monitored by eye-tracking and a subsequence survey, the authors tested the impact of PMEs on common products. Combining different pairs of products, where one product had a PME, whereas the other did not, the authors could evaluate if preference correlated with the presence of a PME.

Findings

The authors found both types of PMEs to have analogous effects on participants’ preferences and correlate with participants’ visual attention. The authors also found evidence for a positive influence on a later explicit justification for the specific choice.

Research limitations/implications

This study was conducted in a lab environment and solely related to health-related decisions. The authors still need to know if these findings are transferable to real in-store decisions and other needs such as high quality or low price. This calls for further research.

Practical implications

The topic is important for food companies, and it might become a priority in managing brand equity, combining consumer preferences, loyalty and communicative fairness.

Originality/value

Using eye-tracking and retrospective interviews brings new insights to consumer’s decision-making and how misleading potentially occurs.

Details

European Journal of Marketing, vol. 51 no. 1
Type: Research Article
ISSN: 0309-0566

Keywords

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