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The purpose of this paper is to investigate the inhibiting properties of six quaternary ammonium salts, three cationic surfactants and two non‐ionic surfactants in 2 M KOH. An attempt also was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency.

The inhibition efficiencies of quaternary ammonium salts, cationic surfactants and non‐ionic surfactants on the corrosion of zinc in 2 M KOH solution were investigated by potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods.

Inhibition efficiencies of quaternary ammonium salts were found to be due to physical absorption on the cathodic sides of zinc electrode and dependence of inhibition efficiencies on substituents were found. Physical adsorption of cationic surfactants on zinc electrode slowed down both anodic and cathodic reactions; thus they were found to be mixed type inhibitors. On the other hand, inhibition behaviour of non‐ionic surfactants was found to be due to adsorption on zinc via polar groups. It was found that non‐ionic surfactants behaved as mixed type inhibitors.

Clarifies the role of molecular structure and substituents on the inhibition efficiency of surfactants and quaternary ammonium compounds on the corrosion of zinc in alkaline media.

The purpose of this paper is to enhance the understanding on the electrodeposition of various lead (Pb)‐free solder alloys, so that new studies can be carried out to solve processing issues.

The paper reviews the available reports on the electrodeposition of tin (Sn)‐based solder systems and identifies the challenges in this area.

Compositional control remains a major challenge in this area, where the achievement of desired composition for binary and ternary alloys is subjected to uncertainties. The use of chelating agents in the bath and optimization of parameters can assist the achievement of near‐desired alloy composition. Acidic plating baths are preferred due to their compatibility with photoresists but oxidation of stannous ions causes poor bath stability. Antioxidants, reducing agents and low oxygen overpotential anodes can suppress the oxidation rate and increase the lifespan of plating baths. Apart from chelating agents and antioxidants, various categories of additives can be added to improve quality of deposits. Surfactants, grain refiners and brighteners are routinely used to obtain smooth, fine‐grained and bright deposits with good thermo‐mechanical properties.

The paper provides information on the key issues in electrodeposition of Pb‐free solder alloys. Possible measures to alleviate the issues are suggested so that the electrodeposition technique can be established for mass production of a wider range of solder alloys.

Copper electrodeposition acts as a crucial step in the manufacture of high-density interconnect board. The stability of plating solution and the uniformity of copper electrodeposit are the hotspot and difficulty for the research of electrodeposition. Because a large number of factors are included in electrodeposition, experimentally determining all parameters and electrodeposition conditions becomes unmanageable. Therefore, a multiphysics coupling technology was introduced to investigate microvia filling process, and the mechanism of copper electrodeposition was analyzed. The results provide a strong theoretical basis and technical guidance for the actual electroplating experiments. The purpose of this paper is to provide an excellent tool for quickly and cheaply studying the process behavior of copper electrodeposition without actually needing to execute time-consuming and costly experiments.

The interactions among additives used in acidic copper plating solution for microvia filling and the effect on the copper deposition potential were characterized through galvanostatic measurement (GM). The adsorption behavior and surface coverage of additives with various concentrations under different rotating speeds of working electrode were investigated using cyclic voltammetry (CV) measurements. Further, a microvia filling model was constructed using multiphysics coupling technology based on the finite element method.

GM tests showed that accelerator, inhibitor and leveler affected the potential of copper electrodeposition, and bis(3-sulfopropyl) disulfide (SPS), ethylene oxide-propylene oxide (EO/PO) co-polymer, and self-made leveler were the effective additives in acidic copper plating solution. CV tests showed that EO/PO–Cu⁺-Cl⁻ complex was adsorbed on the electrode surface by intermolecular forces, thus inhibiting copper electrodeposition. Numerical simulation indicated that the process of microvia filling included initial growth period, the outbreak period and the stable growth period, and modeling result was compared with the measured data, and a good agreement was observed.

The research is still in progress with the development of high-performance computers.

A multiphysics coupling platform is an excellent tool for quickly and cheaply studying the electrodeposited process behaviors under a variety of operating conditions.

The numerical simulation method has laid the foundation for mechanism of copper electrodeposition.

By using multiphysics coupling technology, the authors built a bridge between theoretical and experimental study for microvia filling. This method can help explain the mechanism of copper electrodeposition.

BASF Lacke + Farben AG, Muenster (Federal Republic of Germany) and Tanabe Chemical Industries Co Ltd., Osaka (Japan) have established a joint company for the sale of OEM automotive paints. THe agreement was signed in Osaka by Hrimata Tanabe, President of Tanabe Chemical Industries, and Dr Juergen F Kammer, member of the Board of BASF Lacke + Farben AG.

The purpose of this investigation is the evaluation of the inhibitive performance of a new “gemini” surfactant in the series of bis‐quat: N, N, N′, N″, N″‐pentamethyl diethyleneamine‐N, N″‐di‐[tetradecylammonium bromide] on the corrosion of iron in 1 M HCl by gravimetric, potentiodynamic and electrochemical impedance measurements. The effect of the temperature on the corrosion behavior of iron in 1 M HCl without and with inhibitor is studied in the temperature range (298‐333 K). This work also attempts to correlate thermodynamic and kinetic parameters with the inhibition effect.

The inhibition efficiency of gemini synthesized is investigated by weight loss, potentiodynamic polarization and impedance spectroscopy methods.

The synthesized gemini bis‐quat acted as a good inhibitor in 1 M HCl, and inhibition efficiency increased with inhibitor concentration and temperature. Polarization curves showed that the surfactant was a mixed‐type inhibitor in hydrochloric acid. Impedance spectroscopy measurements showed that the inhibitor acted through the formation of a multilayer film at the iron surface. The adsorption of inhibitor on the iron surface obeyed the Langmuir adsorption isotherm equation. The inhibition effect was satisfactorily explained by both thermodynamic and kinetic parameters.

The adsorption of surfactants in the metal surface can markedly change the corrosion resisting property of the metal. So the study of the relation between the adsorption and corrosion inhibition is of a great importance. This was the first attempt to study the inhibition properties of gemini surfactants at the host laboratory.

The purpose of this research is to study different extra-heavy crude oil-in-water emulsions that can be found in practice for corrosion process of X52 steel adding 60 mg.L-1 of non-ionic surfactant and a corrosion inhibitor (CI). Electrochemical impedance spectroscopy and Tafel plots are carried out. Thus, Bode-modulus and Bode-phase angle plots are discussed. Adsorption isotherms obtained from corrosion rate (CR) values are taken into account.

Two-electrode arrangement is used to characterize the pseudo-capacitance values for X52 steel exposed to water and crude oil phases, mainly. Electrochemical evaluations for X52 steel exposed to extra-heavy crude oil-in-water emulsions are recorded in a conventional three-electrode cell to study the corrosion process as was documented in detail by Quej-Ake et al. (2015). Therefore, all electrodes are placed as close as possible to eliminate the iR-drop.

Pseudo-capacitance analysis shows that X52 steel immersed in oilfield produced water was more susceptible to corrosion than that immersed in ocean water solution and extra-heavy crude oil phase. After being analyzed, the X52 steel surface coverage and adsorption process for surfactant and CI could be concluded that surfactant could protect the metal surface. In a coalescence extra-heavy crude oil-in-water emulsion, the water medium generated a new solution that was more corrosive than the original water phase. Wash crude oil process was provoked in emulsion systems to sweep up the salts, mainly. Thus, corrosive species that can be recovered inside extra-heavy crude oil may appear, and in turn a new more corrosive solution could be obtained. Taking into account the straight line obtained in Bode-modulus plot for X52 exposed to extra-heavy crude oil, it is possible to point out that the negative value of the slope or R² can be related to a coefficient (Jorcin et al., 2006). It is important to mention that electrochemical responses for X52 steel exposed to extra-heavy crude oil-in-water under coalescence emulsions revealed that corrosion and diffusion processes exist. Therefore, a possible good inhibitor is surfactant in emulsion systems.

CR and anodic and cathodic slopes suggest that the surfactant acted as mixed CI. Of these, susceptible anodic (MnS and perlite or cementite) and cathodic (ferrite) sites on steel surface could be affected, due to which physicochemical adsorption could happen by using electrochemical parameters analysis. Thus, no stable emulsions should be taken into account for extra-heavy crude oil transportation, because corrosion problems in atmospheric distillation process of the crude oil due to stable emulsion cannot be easily separated. In this manner, coalescent emulsions are more adequate for transporting extra-heavy crude oil because low energy to separate the water media is required.

In this research, the microstructure and corrosion behavior of Ni-Mo alloy coatings obtained from a citrate bath solution containing sodium dodecyl sulfate (SDS) as an anionic surfactant, and cetyltrimethylammonium bromide (CTAB) as a cationic surfactant, have been investigated.

For this purpose, the Cathodic polarization curves were plotted using a potentiostat/galvanostat set. Scanning electron microscopy and energy dispersive spectroscopy were, respectively, used to investigate the morphology and chemical composition of the coatings.

The results of the corrosion test showed that the corrosion resistance of the coatings obtained from electroplating bath only containing CTAB surfactant was deteriorated. On the other hand, SDS anionic surfactant positively affected on the corrosion resistance of the coatings when it was added to the electroplating bath.

For this purpose, the Cathodic polarization curves were plotted using a potentiostat/galvanostat set. Scanning electron microscopy and energy dispersive spectroscopy were respectively used to investigate the morphology and chemical composition of the coatings.

Surfactants have been reported to have high inhibition efficiencies for corrosion of steel. This paper aims to study the performance of a low toxic copolymer of polydimethylsiloxane and polyoxyalkylene (POA) surfactant named as POPS, as a corrosion inhibitor for mild steel (ASTM 1005) in hydrochloric acid (HCl) solution at 25°C.

To evaluate POPS efficiency as a corrosion inhibitor, the following techniques were used: surface tension measurements, weight loss measurements, open circuit potential monitoring, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscopy and contact angle measurements.

Results indicated that POPS acted as a mixed corrosion inhibitor and led to a hydrophobic protector film on the metal surface. The adsorption process obeyed the Langmuir adsorption isotherm by chemisorption. The maximum efficiency of the surfactant studied was achieved in a concentration around the critical micelle concentration.

Surfactant (POPS) of low level of toxicity acts as a mixed corrosion inhibitor in HCl medium. Inhibitor film formation was characterized by EIS results. A mechanism for corrosion inhibition is proposed.

Surfactants are important corrosion inhibitors that are used in different applications. This paper utilizes the recently developed methodology and formulae to predict mild steel corrosion inhibition by alkyl pyridinium chloride and alkyl trimethyl ammonium bromide compounds. By utilizing different surfactants of varying chain lengths in different acidic media and determining the associated corrosion inhibition, the relationship between surfactant concentration, surfactant hydrocarbon chain length, surfactant critical micelle concentration, and corrosion inhibition can be evaluated. The results from this study can be used to improve relevant industrial uses of surfactants for corrosion inhibition.