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The purpose of this paper is to optimize experimental parameters and gain further insights into the plating process in the fabrication of high-density interconnections of printed circuit boards (PCBs) by the rotating disc electrode (RDE) model. Via metallization by copper electrodeposition for interconnection of PCBs has become increasingly important. In this metallization technique, copper is directly filled into the vias using special additives. To investigate electrochemical reaction mechanisms of electrodeposition in aqueous solutions, using experiments on an RDE is common practice.

An electrochemical model is presented to describe the kinetics of copper electrodeposition on an RDE, which builds a bridge between the theoretical and experimental study for non-uniform copper electrodeposition in PCB manufacturing. Comsol Multiphysics, a multiphysics simulation platform, is invited to modeling flow field and potential distribution based on a two-dimensional (2D) axisymmetric physical modeling. The flow pattern in the electrolyte is determined by the 2D Navier–Stokes equations. Primary, secondary and tertiary current distributions are performed by the finite element method of multiphysics coupling.

The ion concentration gradient near the cathode and the thickness of the diffusion layer under different rotating velocities are achieved by the finite element method of multiphysics coupling. The calculated concentration and boundary layer thicknesses agree well with those from the theoretical Levich equation. The effect of fluid flow on the current distribution over the electrode surface is also investigated in this model. The results reveal the impact of flow parameters on the current density distribution and thickness of plating layer, which are most concerned in the production of PCBs.

By RDE electrochemical model, we build a bridge between the theoretical and experimental study for control of uniformity of plating layer by concentration boundary layer in PCB manufacturing. By means of a multiphysics coupling platform, we can accurately analyze and forecast the characteristic of the entire electrochemical system. These results reveal theoretical connections of current density distribution and plating thickness, with controlled parameters in the plating process to further help us comprehensively understand the mechanism of copper electrodeposition.

The rate of copper dissolution in the presence of phosphoric acid‐alcohol mixtures was studied by measuring the limiting current density which represents that the rate of electropolishing is decreased by increasing phosphoric acid concentration, electrode height, and mole fraction of alcohol. Thermodynamic parameters are calculated. The rotating disk electrode is being used as a tool to study the influence of organic solvent addition on the rate of electropolishing of copper. Different reaction conditions such as temperature, speed of rotation of copper disk, the physical properties of solution are studied to obtain a dimensionless correlation between all these parameters. The data can be correlated by the following equations: Sh = 1.835 (Sc)^0.33 (Re)^0.36 (for ethylene glycol) Sh = 1.25 (Sc)^0.33 (Re)^0.5 (for glycerol) It is obvious that the exponent in the two cases denotes a laminar flow mechanism.

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.

The efficacy of antiscaling treatments under simulated flow conditions was studied by chronoamperometric technique. The effect of temperature and concentration on the scale forming behaviour of different compounds were also studied under the simulated flow conditions. In order to simulate the flow conditions a rotating disc electrode technique was employed. The mechanism of antiscaling behaviour of different chemicals was studied through electrochemical impedance spectroscopy. It was found that the flow velocity affected the efficiency of antiscalants. Polymer based compounds follow the growth modification adsorption mechanism, while compounds like EDTA and phosphonate follow nucleation modification absorption/chemisorption mechanism. Temperature and concentration of the scale forming compounds have a significant role in the scaling process, particularly at the low concentrations.

The purpose of this paper is to study the corrosion rate for X52, X60, X65, X70 and X80 steel immersed in Mexican oilfield produced water. For the electrochemical characterization of the five steels rotating disk electrodes, 20°C, 30°C and 45°C of experimental temperature and 0, 500, 1,000 and 2,000 rpm of rotation speed were taken into account. The temperature dependence was analyzed using Arrhenius law. Thus, Rct values obtained from EIS data in comparison with the corrosion rate obtained from polarization curves data were taken into account. Hydrodynamic effects were analyzed by Rct and corrosion rate data.

Electrochemical impedance spectroscopy and potentiodynamic polarization techniques were used to assess the electrochemical behavior for five pipe steels steel immersed in a natural solution.

The resistance and corrosion rate taken from electrochemical tests decreased as temperature and hydrodynamic condition also decreased. In addition, the Arrhenius parameter revealed that the natural solution increased the corrosion rate as the activation energy decreased. Typical branches related to reduction-oxidation reaction (dissolution-activation process or corrosion products dissolution) on steel surface were discussed. Optical images analysis shows that corrosion products for X65 steel exposed to oilfield produced water can be attributed to more susceptibility to corrosion damage for this steel grade (Quej-Ake et al., 2018), which is increased with the temperature and rotation speed of the working electrode.

Corrosion process of the five steels exposed to oilfield produced water could be perceptive when Arrhenius analysis is taken into account. This is because oilfield produced water is the most aggressive condition (brine reservoir and sour water) for internal pipelines walls and storage tanks (brine tanks). Thus, stagnant condition was considered as a more extreme corrosive condition because produced water is stored in atmospheric stationary tanks as well as it is transported under laminar condition in zones where oilfield produced water is maintaining in the bottom of the pipe during the production, transporting and storing of the crude oil. In addition, a brief operational process for Reynolds number and the flowrate of the stock tank barrel per day (Q in STBD) using field and Reynolds number data is discussed.

Experiments were conducted with carbon steel to investigate the corrosion protection performance of five commercial chemicals as inhibitors in oil field effluent and aquifer waters. The effect of different inhibitor concentrations and flow velocity was determined using the disc electrode (RDE) method. The corrosion rate of carbon steel under stagnant and flow conditions was determined by the linear polarization resistance (LPR) method at a scan rate of 0.1mV/s versus a saturated calomel electrode (SCE). All experiments were conducted at 82^○C. Results indicated that a blend of ethoxylated amine inhibitor for the effluent water, alkylpyridinium‐oxyalkylated‐alkylphenol amine salts inhibitor was found to be the best for both the effluent and aquifer waters.

The purpose of this study is to examine the Darcy–Forchheimer flow of viscous nanoliquid because of a rotating disk. Thermophoretic diffusion and random motion aspects are retained. Heat and mass transfer features are analyzed through convective conditions.

The governing systems are solved numerically by the shooting technique.

Higher porosity parameter and Forchheimer number Fr depict similar trend for both velocity profiles f' and g. Both temperature and concentration profiles show increasing behavior for higher Forchheimer number Fr. An increase in Prandtl number Pr corresponds to lower temperature profile, while opposite trend is noticed for thermal Biot number. Larger concentration Biot number exhibits increasing behavior for both concentration and its associated layer thickness.

To the best of the author’s knowledge, no such consideration has been given in the literature yet.

The purpose of this paper is to introduce bio-inspired FeN₄-S-C black nano-electrocatalyst for the oxygen reduction reaction (ORR) in an alkaline medium. The FeN₄-S-C derived without pyrolysis of precursors in high temperature is recognized as a new electrocatalyst for the ORR in an alkaline electrolyte. For the proper design of bio-inspired nano-electrocatalyst for the ORR performance, chlorinated iron (II) phthalocyanine nanoparticles were used as templates for achieving the active sites in aqueous KOH by rotating disk electrode methods. The most active FeN₄-S-C catalyst exhibited a remarkable ORR activity in the alkaline medium. The objectives of this paper are to investigate the possibility of nanoscale particles size (Ëœ5nm) of electrocatalyst, to achieve four-electron transfer mechanism and to exhibit much superior catalytic stability in measurements. This paper will shed light on bio-inspired FeN₄-S-C materials for the ORR catalysis in alkaline fuel cells.

The paper presents a new bio-inspired nano-electrocatalyst for the ORR, which has activity nearby platinum/carbon electrocatalyst. Chlorinated iron phthalocyanine nanoparticles have been used as FeN₄ template, which is the key point for the ORR. Bio-inspired nano-electrocatalyst has been fabricated using chlorinated iron phthalocyanine, sodium sulphide and carbon black.

The particles’ size was 5 nm and electron transfer number was 4.

The catalyst that is used in this method should be weighed carefully. In addition, the solvent should be a saturated solution of NaCl in water.

The method provides a simple and practical solution to improving the synthesis of iron-based catalyst for ORR.

The method for the synthesis of bio-inspired electrocatalyst was novel and can find numerous applications in industries, especially as ORR non-precious metal catalyst.

The aim of this study is to determine the variation of the different oil analysis instruments in terms of standard deviation and CV‐values, when measuring samples of fully formulated hydraulic and gear oils taken from working systems.

In this investigation, two different spectrometric techniques, inductively coupled plasma‐optical emission spectrometers (ICP‐OES) and rotating disk electrode‐optical emission spectrometers (RDE‐OES), have been studied to determine the instruments' precision of measurement and ability to measure the absolute level of contamination. The study was based on a series of measurements using artificial contamination mixed with oil.

The ICP has better precision of measurement of the two instruments, but cannot predict the absolute values of contamination when oil samples are only treated by organic solvent dilution if the samples include large or dense particles. It is therefore not too good, with the sample pre‐treatment method used, at detecting wear processes that produce dense/large particles, such as pitting failure. For instance, microwave‐assisted acid digestion could be used for sample pre‐treating to obtain accurate results in that case. It should, however, be able to detect wear mechanisms that produce small particles such as abrasive wear in any case. The ICP has a repeatability value of r=3 percent and a reproducibility value of R=12 percent for contamination levels of between 50 and 400 ppm and r=0.6  and R=2 ppm, respectively, at values below 50 ppm. The RDE cannot predict the absolute value of contamination if this includes large or dense particles if proper sample pre‐treatment is not used. It is therefore not good at detecting wear mechanisms that produces dense/large particles (if the oil samples are not pre‐treated properly) such as pitting but should be able to detect abrasive wear and similar processes that produce small particles in any case. The RDE's precision of measurement is not as good as the ICP, with a reproducibility variation of R=r=25 percent for contamination levels between 20 and 500 ppm and R=r=6 ppm for contamination level below 20 ppm.

Only the effects from lubricating oils are studied.

This study will significantly increase the industrial knowledge concerning measurement precision in particle contamination measurement systems.

No similar study is found.

The purpose of this paper is to study the effects of temperature, dissolved oxygen (DO) and velocity of seawater on corrosion behavior of three copper‐based alloys (admiralty brass, aluminum brass and Cu‐5Ni alloy used in condenser tubes).

A series of electrochemical tests were carried out in seawater at different temperatures and DO contents using both stationary and rotating‐disc electrodes in order to investigate the corrosion behavior of alloys under these conditions.

It was found that admiralty brass exhibited a significantly higher corrosion rate and Cu‐5Ni alloy was more resistant to corrosion than were the brasses. With increasing temperature, the corrosion rates of the brasses increased. Selective zinc dissolution took place over the whole temperature range. Increasing temperature decreased the corrosion rate of Cu‐5Ni alloy in seawater due to formation of a passive film. The passivation of the alloy could be explained by the presence of greater proportion of nickel at the metal surface. Brasses, especially admiralty brass, exhibited higher corrosion rates in high concentrations of DO, whereas the Cu‐5Ni alloy was virtually immune to corrosion under such conditions. Increasing the water velocity increased the corrosion rate of admiralty brass but velocity had no effect on the corrosion rate of aluminum brass and Cu‐Ni alloy.

This paper provides information about corrosion behavior of three copper alloys used for common condenser tubes. The study fulfilled the objective of the investigation and contributes to research on corrosion behaviors of copper alloys in seawater.