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To provide a summary of research work carried out mainly in the authors' group for evaluating various protective coatings including rustproofing oils, and also for studying corrosion inhibitors using the wire beam electrode (WBE) method.

A range of published papers published during the past 15 years was summarised and reviewed. Recent research work in the authors' group was also included, which involved the combined use of the WBE with electrochemical noise analysis and the scanning reference electrode technique.

The WBE method has been developed into a very useful tool of evaluating the performance of coatings and inhibitors. In particular, The WBE is uniquely applicable for determining the performance of coatings and inhibitors to control localised corrosion.

Focusing mainly on recent research.

A useful source of information for researchers and graduate students working in the areas of organic coating and inhibitor research.

The first summary or review on this research topic.

The purpose of this work is to design the wire beam electrode (WBE) of P110 steel and study its corrosion behavior and mechanism under high temperature and pressure.

Packaging materials of the new type P110 steel WBE and high pressure stable WBE structure were designed. A metallurgical microscope (XJP-3C) and scanning electron microscopy (EV0 MA15 Zeiss) with an energy dispersive spectrometer were used to analyze the microstructure and composition of the P110 steel. The electrochemical workstation (CS310, CorrTest Instrument Co., Ltd) with a WBE potential and current scanner was used to analyze the corrosion mechanism of P110 steel.

According to the analysis of Nyquist plots at different temperatures, the corrosion resistance of P110 steel decreases with the increase of temperature under atmospheric pressure. In addition, R_p of P110 steel under high pressure is maintained in the range of 200 ∼ 375 Ωcm², while that under atmospheric pressure is maintained in the range of 20 ∼ 160 Ωcm², indicating that the corrosion products on P110 steel under high pressure is denser, which improves the corrosion resistance of P110 steel to a certain extent.

The WBE applied in high temperature and pressure environment is in blank. This work designed and prepared a WBE of P110 steel for high temperature and pressure environment, and the corrosion mechanism of P110 steel was revealed by using the designed WBE.

The purpose of this study was to explore the differences in the corrosion behavior of carbon steel in simulated reverse osmosis (RO) product water, and in seawater.

The wire beam electrodes (WBE) and coupons made from Type Q235 carbon steel and were immersed in simulated reverse osmosis product water, and in seawater, for fifteen days. The corrosion potential distribution on the WBE at different times was measured. The corrosion rates of the carbon steel in different solutions were obtained using weight loss determinations. The different corrosion behavior of carbon steel in the two kinds of solution was analyzed.

The results showed that the average corrosion potential, micro-cathode potential and micro-anode potential of the WBE decreased with time in simulated RO product water. During this period, the maximum potential difference between micro-cathodes and micro-anodes on the WBE surface also decreased with time. The potential difference was more than 260mV at the beginning of the test and was still greater than 110mV after fifteen days of immersion. The positions of cathodes and anodes remained basically unchanged and corrosion took place on the localized anode during the experiments. The average corrosion potential, micro-cathode potential and micro-anode potential on the WBE surface also decreased with time in the simulated seawater. However, the maximum potential difference between micro-cathode and micro-anode on the WBE surface in the simulated seawater was much smaller than was the case in simulated RO product water. It was 37.8 mV at the beginning of the test and was no more than 12mV after two days immersion. The positions of cathode region and anode kept changing, leading to overall uniform corrosion. The actual corrosion rate on the corroded anode region in simulated RO product water was greater than was the case in simulated seawater.

The corrosion behavior differences of carbon steel between in RO product water and in seawater were revealed by using wire beam electrodes (WBE). From the micro point of view, it explained the reason why the actual corrosion rate of carbon steel in RO product water was greater than that in sea water. The results can be helpful to explore future corrosion control methods for carbon steel in RO product water.

The purpose of this paper is to describe the assessment practices reported by Canadian educators and workplace supervisors involved in exemplary work‐based education (WBE) programs for high‐school students.

Six focus groups were conducted, four with teachers and coordinators and two with workplace supervisors from exemplary WBE programs, to identify the features of these exemplary programs that prepare adolescents to participate in WBE, that prepare workplace supervisors to mentor WBE students, and that characterize the day‐to‐day interactions in the workplace through which adolescents learn. Surprisingly, in the absence of any questions directly focused on assessment, participants spoke at length and with passion about the purpose and nature of assessment in their outstanding WBE programs.

Analyses of these interviews revealed six themes that describe the range of assessment practices associated with these three features of exemplary programs: identification of student interests and abilities; student self‐assessment; communication of expectations and responsibilities; contextualized assessment; collaboration between school and workplace; and connections between assessment and instruction.

The findings highlight practical assessment procedures, for teachers and workplace supervisors, which facilitate the meaningful participation and learning of students in WBE programs and of workers in the workplace.

The objective of this work was to develop practical experimental techniques for monitoring corrosion in “difficult‐to‐test” conditions such as corrosion under insulation (CUI).

An electrochemically integrated multi‐electrode array namely the wire beam electrode (WBE) method has been used in combination with noise signature analysis for the first time to monitor the penetration of corrosive species under simulated corrosion‐under‐insulation conditions. Corrosion of aluminium exposed under insulation materials such as rock wool, glass wool, cotton wool and tissue paper has been successfully monitored.

A typical potential noise signature of a major potential jump from AA1100 WBE was observed which corresponded to the corrosive species reaching the WBE surface in WBE current distribution map. A good correlation between the galvanic current maps and the corroded surface was also observed.

The preliminary results suggest that the proposed novel electrochemical method is capable of monitoring CUI.

Unions and organizations interests are often seen to be in competition. However, union-voice hypothesis suggests that unions can provide a distinctive mechanism to lower organizational costs by reducing exit behavior, absence from work and conflict levels at work. This study aims to look at union participation as a form of voice which is affected by a number of antecedents and in turn has an effect upon the workers performance (i.e. worker behavior effectiveness [WBE]) in an organization.

The study draws on data from 340 permanent labors working in 19 manufacturing units across different regions of India to explore both the antecedents and outcomes of union participation. Hypotheses are tested using mediation analysis.

Results indicate statistically significant relationships between union participation, its antecedents and WBE, with union participation partially influencing the relationship between the constructs.

Uniqueness of the study lies in its findings which report positive relationship among union participation, its antecedents and behavior effectiveness. Contrary to the traditional belief that unions are detrimental to the health of any organization, the study suggests that workers decision to join and participate in unions should be viewed positively because only if a person is willing to stay with the organization, he/she seeks to resolve the issues/problems through collective mechanism of union participation and which in turn leads to enhanced performance, reduced absenteeism at the workplace.

Oil-water two-phase flow is the most prevalent medium in oil field gathering pipelines, and the corrosion of pipelines is often highly localized. Therefore, the purpose of this paper is to investigate the corrosion behavior of 20# pipeline steel in the oil-water stratified liquids, vary the water content of the upper emulsion and study the difference of the corrosion process.

Combine the wire beam electrodes (WBE) technique and the corrosion weight loss method to investigate the corrosion behavior of 20# steel in produced water simulation fluid and oil-water stratified liquids, and a corrosion mechanism model was established for analysis and explanation.

The results of mass loss experiments showed that the average corrosion rate increased with the increase in the water content of the upper emulsion. The corrosion current distribution maps indicated that the most serious corrosion occurred in the produced water simulation liquid, and the corrosion process showed the law of waterline corrosion. In addition, it was also found that the corrosion of the WBE in the stratified liquids had obvious non-uniformities. The electrode wires at the oil-water interface suffered from severe corrosion, caused by the dissolution of crude oil acids in water and the uneven distribution of oxygen in the corrosive medium.

The WBE technique provides a deep insight into the corrosion phenomena at the oil-water interface, which is helpful for characterization of the non-uniformity of corrosion parameters and evaluating the risks of multiphase corrosive media.

In electrical discharge machining (EDM) process, the production of separate electrodes for rough, semi‐rough and finish machining of dies and moulds having complex surfaces, results in high cost and long lead‐time in manufacturing. The purpose of this paper is to describe the machining performance of electrodes formed by using copper wire bunches (WBs) positioned to conform the surface to be machined was experimentally and theoretically analyzed. In the study, the variations in the machining rate, electrode wear rate, relative wear and workpiece surface roughness were examined for various discharge current and pulse‐time settings.

Copper WBs positioned to conform the surface to be machined in electric discharge machining. The variations in the machining rate, electrode wear rate, relative wear and workpiece surface roughness were examined experimentally for various discharge current and pulse‐time settings. The WB electrodes (WBEs) are proven to be satisfactory as electrodes for roughing operations in electric discharge machining.

The increase in number of wires and pulse energy result in decrease of relative wear for each wire in the electrode. The increase in number of wires in electrodes causes increase in machining area and in machining time in WBE method. With the increase of discharge current and pulse time, the electrode wear rate and material removal values increase and machining time decreases. By using the mathematical models obtained from the result of the experiments, the electrode wear rate, material removal rate, relative wear and the set length of wires for the desired cavity profile can be calculated. The labor cost of electrode manufacturing in the WBE method is lower compared to conventional solid electrodes. The use of WBE method for rough machining decreases machining cost and time. The use of WBE method decreases both the number of the electrodes required and the delay in starting machining due to the preparation of electrode in EDM.

This paper introduces the benefits of using WBE in electric discharge machining; wear and material removal characteristics of WBEs are introduced; the surface roughness characteristics of surfaces produced by WBEs are examined experimentally; and the effect of number of wires used in WBEs given (experimental findings).

In this study the aim was to investigate under-deposit corrosion (UDC) behavior and the action effects of amino trimethylene phosphonic acid (ATMP) in the oxygen-contained solution.

Electrochemical methods and wire beam electrode techniques were used for the study of ATMP action effect for X65 steel under silica sand and CaCO₃ particle deposit. Electronic coupon technique was used for the study of galvanic effect caused by the deposits and the action effect of ATMP.

ATMP would cause localized corrosion for the silica sand-covered steel. However, it could inhibit the localized corrosion of the steel beneath CaCO₃ particle deposit. Galvanic effect test showed that the galvanic effect caused by the deposits was an important factor for the acceleration of UDC. ATMP had an obvious promotion effect for the galvanic current between bare coupon and silica sand covered coupon and different degrees of localized corrosion were observed beneath both deposits.

The authors believe that the paper may be of particular interest to the readers of the journal as the measurement methods for the UDC of X65 pipeline steel. The experiment they did in the laboratory found that the inhibitor ATMP has a good inhibition effect for bare steel, but it would accelerate the UDC. Different kinds of deposits would have different influences for the UDC behavior with inhibitor added.

The purpose of this study is to investigate the crevice corrosion behavior and mechanism of laser additive manufacturing (LAM) nickel-based alloy under wedge-shaped crevice.

First, the opening size of the wedge-shaped crevice was designed to 0.1, 0.3 and 0.5 mm by controlling the thickness of silicon rubber and the double-side adhesive tape. Then, one side of the glass sheet was stuck on the silicon strip and keep the electrodes of Rows 1 and 2 outside the crevice as a reference, and the opposite side was stuck to the wire beam electrode by silica gel.

The current density with a maximum value of 5.7 × 10⁻⁶ A/cm² was observed at the crevice opening of 0.5 mm, while the lowest value of 9.2 × 10⁻⁷ A/cm² was found at the crevice opening of 0.1 mm. In addition, the corrosion resistance at the inside of the crevice is higher than that at the outside and the middle of the crevice. It means that the internal width of the wedge-shaped crevice tends toward 0, which hinders the migration of ions in the corrosive medium. The generation of corrosive products further reduce the crevice size to cause the inhibition of corrosion at the inside of the crevice as well.

The multilayer and multipath LAM component is prepared to show the complex microstructure, which made the corrosion behavior and mechanism at wedge-shaped crevice nondeterminacy.