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Lack of coating adhesion and bare spot defects of hot-dip galvanized steel plates were experimentally investigated, and the Fe-Al alloy layer was analyzed by both experimental methods and kinetic calculations. Scanning electron microscopy, electron probe micro-analyzer and glow discharge spectrometer method were utilized to determine the microstructures and the distribution of elements of the galvanized steel plates. It is discovered that lack of coating adhesion and bare spot defects depend on the quality of the Fe-Al alloy layer. Fe-Al alloy layer (alias inhibition layer) affects the adhesiveness of the alloy coating to the steel plate, and prevents the interdiffusion process of elements between the zinc pot and the coated steel. The kinetic analysis was carried out by means of CALPHAD (CALculation of PHAse Diagrams) method. Because the main constitutuent of Fe-Al alloy layer is Fe2Al5 phase when the Al content in the liquid Zn is kept below 1 wt.%, diffusion models with Fe2Al5 were constructed to investigate the element distribution during the galvanizing process, and the calculated results can reasonably predict the element distribution trend in both the alloy coating and the steel plate. It is shown that besides the wetting reactions of Fe and Al during the galvanizing process, the diffusion behavior of elements also influences the coating quality. In summary, the appropriate control of Fe-Al alloy layer can prominently benefit the surface quality of the galvanized coatings, and the manufacturing parameters, such as strip speed, galvanizing time and zinc pot temperature, act as important factors on the formation of the Fe-Al alloy layer. The optimum combination of the aforementioned parameters may contribute to the improvement of the coating quality. [ABSTRACT FROM AUTHOR]

The corrosion behavior of galvanized steels and zinc components under atmospheric exposure depends mostly on the corrosion product‐based cover layer formation under the prevailing conditions. The use of agar‐based gel electrolytes makes it possible to use electrochemical methods to obtain a characteristic value from these cover layers that describe their current and future protective capacity. It is shown here that different states of galvanized steel can be distinguished very well under laboratory conditions and that this method is also suitable for use under practical conditions. Based on the characteristic values and assuming future time of wetness, it is very easy to draw up a forecast for the future corrosion rate, which provides plausible values. [ABSTRACT FROM AUTHOR]

The World Health Organization has been involved in male contraceptive development for over 50 years. In line with its functions and mandate, World Health Organization works with diverse stakeholders to support research, develop norms and standards, engage member states, facilitate prequalification, introduction and scale up, measurement, and tracking of contraceptives. World Health Organization has a key role in galvanizing global efforts to ensure universal access to contraception services irrespective of income group. Regarding male contraceptive development, World Health Organization has provided technical leadership, supported early research, created and supported research centers, built research capacity in various countries, and standardized semen analysis procedures. In this paper, a detailed description is provided with examples across the various stages of male contraceptive development. Limited funding to World Health Organization is a key challenge. [ABSTRACT FROM AUTHOR]

Key Takeaways: In the United States, all community and nontransient noncommunity water systems are required to submit an inventory describing the location and makeup of all service lines in their service areas. While the material can be designated as lead, galvanized requiring replacement, nonlead, or unknown, the last two designations require additional steps to be taken in the proposed Lead and Copper Rule Improvements (LCRI). Some utilities have few or no lead service lines, and this inventory requirement, issued by the US Environmental Protection Agency (EPA), may be burdensome to those utilities. This article demonstrates the methodology in EPA's proposed LCRI for verification of construction material, and an alternate validation procedure is proposed. [ABSTRACT FROM AUTHOR]

Copyright of Folklor / Edebiyat is the property of Cyprus International University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: This paper aims to contribute to the performance improvement and the broader application of hot-dip galvanized coating. Design/methodology/approach: First, the ability to provide barrier protection, galvanic protection, and corrosion product protection provided by hot-dip galvanized coating is introduced. Then, according to the varying Fe content, the growth process of each sublayer within the hot-dip galvanized coating, as well as their respective microstructures and physical properties, is presented. Finally, the electrochemical corrosion behaviors of the different sublayers are analyzed. Findings: The hot-dip galvanized coating is composed of η-Zn sublayer, ζ-FeZn13 sublayer, δ-FeZn10 sublayer, and Γ-Fe3Zn10 sublayer. Among these sublayers, with the increase in Fe content, the corrosion potential moves in a noble direction. Research limitations/implications: There is a lack of research on the corrosion behavior of each sublayer of hot-dip galvanized coating in different electrolytes. Practical implications: It provides theoretical guidance for the microstructure control and performance improvement of hot-dip galvanized coatings. Originality/value: The formation mechanism, coating properties, and corrosion behavior of different sublayers in hot-dip galvanized coating are expounded, which offers novel insights and directions for future research. [ABSTRACT FROM AUTHOR]

Galvanizing is an important industrial process to improve the corrosion resistance of advanced high strength steels (AHSSs) that are vital for automotive industries. During galvanizing, nanoscale intermetallic phases with complex crystal structures are formed at the interface between the steel substrate and the zinc overlay. To better understand the nanoscale structures and the interfacial properties between the intermetallics, in this work, we develop a second nearest neighbor (2NN) Fe–Al–Zn ternary Modified Embedded Atom Method (MEAM) potential to describe the crystal structures of the intermetallics, i.e. Fe3Al8, Fe4Zn9 and FeZn13 and to calculate the interfacial structure and energy between them. The developed MEAM potential describes well the complex crystal structures and can be used to investigate the interfacial properties that are difficult to obtain from experiments. The Fe4Zn9, FeZn13 surface energies; the Fe–Fe4Zn9, Fe–FeZn13, Fe3Al8–FeZn13 interfacial energies; and the work of adhesion are calculated with the developed MEAM potential. The results show that FeZn13 crystal orientation has an insignificant effect on the FeZn13 surface energy and the Fe–FeZn13 interfacial energy. A negative interfacial energy is obtained for the Fe–Fe4Zn9 and the Fe–FeZn13 interface. The lowest interfacial energy is obtained in the {100}Fe case. The interfacial energy of Fe3Al8–FeZn13 depends on the surface termination of Fe3Al8 and FeZn13. A low interfacial energy is obtained when the surface termination of Fe3Al8 and FeZn13 are both Fe rich. In contrast, when the surface termination of Fe3Al8 is Al rich or the surface termination of FeZn13 is Zn rich, no low energy, stable interface can be formed between the two phases. [ABSTRACT FROM AUTHOR]

In September 1794, the French army, after conquering much of Belgium and the Netherlands, marched into Aachen. This early campaign of military conquest turned into the first laboratory for the systematic plunder of cultural assets enacted by various post-revolutionary and Napoleonic regimes from 1794 to 1815. Works of art "liberated" from the tyranny of aristocratic and religious ownership were earmarked for the newly opened Musée Central des Arts (now the Louvre) to showcase the enlightened cultural supremacy of Paris. From Aachen, the conquerors took more than the usual loot of movable assets: they "extracted" some forty columns from Charlemagne's famed palatine chapel. Thirty-two of these monoliths, set in the eight gallery-level arches, were already Carolingian-era spolia, having been removed from Rome and Ravenna with as much effort and cost as would be the case a thousand years later. Of particular interest to medievalists is the fact that ten of the Aachen columns were integrated into the architectural fabric of the Galerie des Antiques, the Musée Central des Arts' spectacular collection of Greco-Roman statuary that opened to the public in November 1800. Contemporary documents do not associate these columns with a medieval building, but they consistently underscore their provenance from "the tomb of Charlemagne." After reviewing the resonance that association held for Napoleon, the protracted restitution process that followed his downfall is examined against the emergence of a national patrimonial rhetoric, in part galvanized by the failed return of the ten Aachen columns, which remain in the Louvre to this day. As a study of the contested afterlife of seemingly mute and immovable architectural elements, this article also attends to the way these columns legitimized the modern museum as a radically new type of institution. —Carol Heitz in memoriam [ABSTRACT FROM AUTHOR]

Hot stamping of steel is an innovative process for producing components of higher strength with a significant weight reduction. Conventional hot stamping process is carried out at an elevated temperature in the range of 800 to 950 °C in atmospheric condition. So, a coating is a must to restrict high temperature oxidation and decarburization of the steel substrate. Majorly, Al-Si coating and Zn-based coatings are used for the purpose. However, Al-Si-based coatings are not able to provide sacrificial cathodic protection to steel substrate and the Zn-based coating suffer from the problem of microcracking. In the present study, the pre-Ni coated galvanized boron steels are investigated to understand high temperature phase transformation during austenitization step. Thermodynamic calculations along with Gleeble heat treatment experiments and coating characterizations with SEM, EDS, WDS and XRD shows initial melting of the coating. Subsequent Fe-enrichment in the coating has led to formation of BCC phase which is high melting as well as softer phase compared to Ni-Zn intermetallic. Moreover, the corrosion performance of the prior Ni coated galvanized steel has been evaluated. The presence of zinc in the coating shows sacrificial corrosion protection behavior and the Ni and Fe in the coating have further improved the corrosion rate owing to their barrier protection to the steel. [ABSTRACT FROM AUTHOR]

The paper describes the existing technologies and challenges associated with galvanized metal production at the Novolipetsk Steel (NLMK) plant. Possible ways to improve the process using machine-learning tools are proposed. [ABSTRACT FROM AUTHOR]

This study used the droplet solidification test and fast dip test to investigate the effects of boron on the interfacial heat transfer, contact behavior, naturally deposited film, and microstructure of 3.5 wt pct Si non-oriented silicon steel during sub-rapid solidification. The results showed that boron altered the surface tension of the molten steel, enhancing the interfacial wettability and heat transfer behavior between the steel and substrate. As the boron content increased from 0 to 97 ppm, the final contact angle decreased from 125 to 96 deg, while the maximum heat flux increased from 6.89 to 10.29 MW/m2, ultimately enhancing the surface quality of the cast strip. During the solidification of boron-containing silicon steel, boron volatilizes and combines with oxygen to form B2O3 on the substrate surface. It reduced the proportion of high melting point silicon oxides in the deposited film, decreasing its melting point. Furthermore, due to boron segregation and improved interfacial heat transfer, the average grain size of the cast strip decreased from 256 to 216 μm, accompanied by a more complex grain orientation. [ABSTRACT FROM AUTHOR]

This article presents the results of research on the growth kinetics, microstructure (SEM/EDS/XRD), and corrosion behavior of Zn-5Al coatings obtained using a high-temperature hot dip process on B500B reinforcing steel. The corrosion resistance of the coatings was determined using the neutral salt spray (NSS) test (EN ISO 9227). Based on chemical composition tests in micro-areas (EDS) and phase composition tests (XRD), corrosion products formed on the coating surface after exposure to a corrosive environment containing chlorides were identified. In the outer layer of the coating, areas rich in Zn and Al were found, which were solid solutions of Al in Zn (α), while the diffusion layer was formed by a layer of Fe(Al,Zn)3 intermetallics. The growth kinetics of the coatings indicate the sequential growth of the diffusion layer, controlled by diffusion in the initial phase of growth, and the formation of a periodic layered structure with a longer immersion time. The NSS test showed an improved corrosion resistance of reinforcing bars with Zn-5Al coatings compared to a conventional hot-dip-galvanized zinc coating. The increase in corrosion resistance was caused by the formation of beneficial corrosion products: layered double hydroxides (LDH) based on Zn2+ and Al3+ cations and Cl− anions and simonkolleite—Zn5(OH)8Cl2·H2O. [ABSTRACT FROM AUTHOR]

China's Belt and Road Initiative has galvanized new Chinese migration to Southeast Asia, including Indonesia. The presence of the new Chinese migrants (Xinyimin) has not gone without resistance in Indonesia. This study examines the effects of history of intergroup conflicts and contact on the formation of threat perceptions toward the Xinyimin in Indonesia. The findings revealed both history of conflicts and contact predict realistic threat and highlight the importance of open communication in mitigating intergroup biases. [ABSTRACT FROM AUTHOR]

Amid the Russian invasion of Ukraine, TikTok has emerged as a pivotal platform, where creators utilize its compressed video formats to mediate the harsh realities of war zones. In this article, we examine 97 videos produced by 12 Ukrainian and Russian TikTok creators in response to the 2022 war in Ukraine. We focus on the playful embodiment of trauma using digital ethnography, analyzing creators' practices and their interconnected memetic communication on TikTok. We identified the use of play through three dynamic practices where platforms, bodies, and trauma converge: (1) the utilization of POV (point-of-view) aesthetic in shareable templates to convey the realities of war from engaging first-person perspectives; (2) the incorporation of dance as a means of embodied creative expression and amplification of trauma; and (3) the harnessing of platform features to facilitate whimsical dialogues with followers about life under war. We argue that playfulness is entrenched in and enacted through platform vernacular modes, driving creators to forge communal ties during adversities and shape the ongoing representation of trauma and its accelerated visibility in digital spaces. We present the concept of playful trauma as a framework for understanding the structural dissonance that arises when creators utilize their bodies alongside platform-specific humorous, ironic, or subversive dialects to perform and amplify the gravity of trauma. This tension provides a unique space for creators to convert their shared experiences of grief and resilience into participatory coping mechanisms. In doing so, they subject and harness their playful platformed body as both the medium and the message, documenting injustices, bearing witness, and galvanizing crowds into action during times of war. [ABSTRACT FROM AUTHOR]

The dependencies establishing the relationship between the tensile stresses, maximum stresses, and parameters of asymmetric out-of-flatness of strips during elastic tension for the biquadratic law of stress distribution over the width have been obtained. A comparative analysis of the obtained dependences with those known for the quadratic law of stress distribution is performed. The obtained dependencies allow the stresses and parameters of out-of-flatness to be calculated more accurately in case of partial concealment of a defect in the stretched strip and, accordingly, its treatment modes to be adjusted (for example, during drawing, hot-dip galvanizing, and continuous annealing). A more accurate calculation of the maximum stresses along the width, taking into account the asymmetry of the defect, makes it possible to reduce the probability of strip breakage and stabilize the technology of their production. The obtained dependencies can be applied in automatic flatness control systems for the production of cold-rolled strips. [ABSTRACT FROM AUTHOR]

The hot‐dip galvanizing behavior of an advanced high‐strength steel DP980 is investigated, focusing on selective oxidation and reactive wetting, as compared with interstitial‐free (IF) steel. The steels are annealed with varying dew points of −50, −25, and 0 °C, and then immersed in a galvannealing bath containing 0.13 wt% dissolved Al. The results show that higher concentrations of Mn and Si elements in DP980 steel result in an increase of nonwettable Mn2SiO4/MnSiO3. The increase in dew point does not promote the internal oxidation of alloying elements in DP980 as in IF steel, and DP980 displays the lowest external oxidation at −50 °C. After galvanizing, Mn and Si oxides are observed above the inhibition layer, which is due to the oxide cracking caused by the mismatch of thermal expansion coefficient between the surface oxides and the steel, and then the oxide flaking and incorporation are caused by the interfacial infiltration through cracks and the formation of intermetallic crystals of Fe–Al and subsequent Fe–Zn. Therefore, IF steel maintains good wetting in the presence of external oxides, while DP980 steel exhibits more external film oxides and poor coating quality at high dew points. [ABSTRACT FROM AUTHOR]

The hot-dip galvanizing pot in a certain steel plant often experiences severe vibrations. In order to investigate the cause of the vibrations in the hot-dip galvanizing line and further clarify the vibration characteristics of the sinking roller system in the high-temperature zinc liquid, this study first used SolidWorks to establish a three-dimensional model of the sinking roller system in the steel plant and then used Ansys Workbench software to perform modal analysis on the hot-dip galvanizing sinking roller system. Considering the complex flow field and loading conditions inside the zinc pot, this article analyzes the vibration characteristics of the sinking roller system under four main external factors, namely, dry mode, wet mode, prestress mode, and thermal stress mode, in a zinc pot, and the natural frequency changes of the sinking roller system under different density fluids, different loading conditions, and different temperatures were analyzed according to the actual working conditions. The calculation results showed that the natural frequency of the sinking roller device significantly decreased, and the order of mode shapes changed when considering the additional mass of the high-temperature zinc liquid. The tension generated by the strip steel had little effect on the natural frequency of the sinking roller device. The thermal stress generated inside the sinking roller system at high temperatures slightly reduced the natural frequency of the sinking roller device in the high-frequency region, but compared to the decrease caused by the inertia effect of the liquid, it was much smaller. The main mode shapes under the action of prestress and thermal stress were almost unchanged compared to the dry mode; in some mode shapes, excessive deformation of the sliding bearings at both ends of the sinking roller system causes roller displacement. This study theoretically analyzed the vibration characteristics of the sinking roller system, compared the influence of the main external loads in the zinc pot on the vibration characteristics of the sinking roller system, and analyzed the possible reasons for the failure of the sliding bearing of the sinking roller system under certain mode shapes, providing a reference for subsequent vibration reduction and optimization design of the sinking roller system. [ABSTRACT FROM AUTHOR]

Objective: In a southcentral Alaska stream system, we conducted a study to evaluate the effect of trap type (galvanized and nylon coated), bait type (salmon roe cured with and without sodium sulfite), and soak times (1 h and 24 h) on captures of juvenile salmon using Gee‐style minnow traps. This was undertaken due to the limited research on this topic, aiming to determine how variations in methodology affected captures in juvenile salmon. Methods: We employed a three‐way fixed factorial design to sample 176 stream reaches (with a single trap in each each) from June 2021 to September 2021, capturing 296 Coho Salmon Oncorhynchus kisutch and 105 Chinook Salmon O. tshawytscha. Result: We found an estimated 78% decrease in captures of Coho Salmon when nylon‐coated traps were used instead of galvanized traps, and we found that trap type showed no effect on number of captures for Chinook Salmon. Additionally, we did not detect effects of bait type and soak time on the number of captures for either species. Not surprisingly, there was a positive relationship between Julian date and temperature with captures for both species. Additionally, for Coho Salmon, we found a quadratic relationship between water velocity and captures. Conclusion: Understanding and accounting for these factors will help researchers to maximize trapping efficiency, standardize protocols, and determine the extent to which results are comparable across studies employing different methods. Impact statementOur study examined how different trap materials, bait types, and soak times affect the capture of juvenile salmon. We found that using nylon‐coated traps decreased Coho Salmon by 78%, while trap type had no effect on Chinook Salmon. These findings help researchers optimize trapping methods, ensuring accurate and comparable results. [ABSTRACT FROM AUTHOR]

Fiber photodetectors (FPDs) are promising candidates for wearable applications due to their flexibility, knittability, and full‐angle detection. The current state‐of‐the‐art FPDs based on inorganic photosensitive materials show drawbacks in mechanical flexibility. The organic FPDs (OFPDs) are superior, while the fabrication is limited by multi‐layer process compatibility issues. Herein, a diode‐type five‐layer OFPD with Zn/ZnO/PBDB‐T:ITIC‐Th/MoO3/PEDOT:PSS structure is prepared by combining thermal evaporation with a successive dip‐coating method. It is worth mentioning that the uniform coaxial MoO3 interfacial layer is processed by the proposed fiber‐compatible thermal evaporation technique, while the other functional layers are enabled by the solution‐based dip‐coating method. At the bias of −0.5 V, the optimized OFPD exhibits a dark current density of 8.46 × 10−8 A cm−2, a responsivity of 86.4 mA W−1 (@ 760 nm), and a specific detectivity of over 1011 Jones in the visible range of 400–760 nm. Besides, the device displays a fast response speed of 0.44 and 0.14 ms for rise and fall time, showing the capability of full‐angle detection. The device is demonstrated in photoplethysmography for real‐time heart‐rate monitoring, suggesting its potential for practical application in wearable electronics. [ABSTRACT FROM AUTHOR]

The corrosion of steel materials has become a global issue, causing significant socio-economic losses and safety concerns. Hot-dip galvanizing is currently one of the most widely used steel anti-corrosion processes. With the rapid advancement of science and technology and emerging industries, the performance of pure galvanized products struggles to meet the demands of practical applications in various environments. Consequently, researchers have begun introducing various metals into the zinc solution to form high-performance alloy coatings. This article primarily explains the process flow of hot-dip galvanizing and the impact of metal elements such as Al, Mg, Sn, and Bi on the coating, as well as outlining the major issues currently faced by the hot-dip galvanizing process. The objective is to offer a more comprehensive introduction to those new to the field of hot-dip galvanizing and to provide theoretical insights for addressing production issues. [ABSTRACT FROM AUTHOR]

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the pre-oxidation products, surface silicon content, hot-dip galvanized layer structure and corrosion resistance of nodular cast iron pre-oxidized by sodium bicarbonate were studied by scanning electron microscopy, energy-dispersive spectrometry, X-ray diffraction. When the pre-oxidation temperature is 100 °C, the pre-oxidation product is primarily Fe2O3. The oxidation products are Fe2O3 and SiO2 at 200 °C and that is mainly SiO2 at 300 °C. The surface silicon content of the pre-oxidized samples decreases first and then increases with increasing pre-oxidation temperature. The silicon content of samples after alkali and acid washing decreases with increasing pre-oxidation temperature. With the increase in pre-oxidation temperature, the thickness of the alloy layer in the zinc coating of nodular cast iron continuously decreases. The thickness of the alloy layer in the zinc coating of nodular cast iron pre-oxidized at 300 °C is only 37.3 μm, which is 43.9% lower than that of nodular cast iron without pre-oxidation. [ABSTRACT FROM AUTHOR]

In this work, we performed a reliable study of the IEF model, which calculates the critical stress intensity factor, KIC, already studied in our previous article (Daoud et al. Int J Adv Manuf Technol 92:569–581, 2017), by the Phimeca-soft, where we performed a parametric study of the variation of the reliability index (β) as a function of the crack length (a) of the three states G1(x), G2(x) and G3(x) of the four sample types (R2, R4, R10 and R80), and also found the FORM/SORM results, as well as the histogram of elasticity of all variables used in the reliability study for the four sample types, with E26 galvanized sheet, safety and failure domains depending on the limit state used and importance of calculation variables on the reliability of the fracture. Then, the critical stress intensity factor (KIC) was found by the analytical method (IEF Model) equal to 63.13 MPa.m1/2 (accurate but not precise value), by the numerical method using the software Franc2D equal to 57.94 ± 4.29 MPa.m1/2 (precise but not accurate value) and by the reliability method using the software Phimeca-soft equal to 38.93 ± 0.83 MPa.m1/2 (accurate and precise value). [ABSTRACT FROM AUTHOR]

In recent decades, batch hot-dip galvanized (HDG) steel has proven itself in practical applications due to the good corrosion resistance of its components. Despite the importance of the mechanical-load-bearing capacity of these coatings, the wear behavior has, so far, only been investigated very sporadically and not systematically, so a quantification of the wear behavior and statements on the mechanisms are vague. Therefore, two body wear tests with bonded abrasive grain were carried out. Varying the friction rolls, load, and total number of cycles, the wear behavior was investigated. The mass loss and the layer thickness reduction were measured at different intervals. After the test, the microstructure in the cross-section and the hardness according to Vickers (0.01 HV) were evaluated. The results showed that the wear behavior of HDG coatings against abrasive loads can be characterized with the selected test conditions. Initially, the applied load removed the soft η-phase. As the total number of cycles increases, the η- and ζ-phases deform plastically, resulting in a lower mass reduction compared to that expected from the measured layer thickness. The characteristic structure of a batch HDG coating with hard intermetallic Zn-Fe phases and an outer pure zinc phase has demonstrated effective resistance to abrasion. [ABSTRACT FROM AUTHOR]

Recently, for the high performance of automobiles, the application ratio of zinc-coated steel sheets with excellent corrosion resistance has been increasing. However, it is difficult to achieve sound welds, as porosities form from zinc during welding. In this study, a laser welding process, with the addition of a pretreatment step to conventional laser welding, was devised to improve weld quality by eliminating pores caused by zinc in the welds. Laser welding was performed on the overlapping joint of hot-dip galvanized steel sheets (SGARC 340, Hyundai Steel., Suncheon-Si, Jeollanam-do, Republic of Korea), with a thickness of 1.2 mm in the upper sheet and 0.9 mm in the lower sheet, and the welding characteristics were investigated by varying the laser power and focal position. Compared to conventional laser welding, the three-step laser stitch welding process significantly reduced the degree of spatter generation and welding defects. Additionally, it increased the tensile–shear load by approximately 37%. Moreover, the reduction in the zinc component of the three-step laser stitch welds was confirmed through SEM-EDS analysis. These findings contribute valuable information for securing high-quality welding joints and effectively addressing zinc-coated steel sheet welding quality issues in the automotive and industrial sectors. [ABSTRACT FROM AUTHOR]

Rehabilitation of corroded buried galvanized steel structures, including corrugated metal culverts (CMCs) and pipes (CMPs), requires a deep understanding of the corrosion process and the corresponding deterioration. The current paper describes an accelerated laboratory corrosion test of corrugated galvanized steel coupons exposed to sequenced wetting/drying cycles ranging from 50 and up to 1600 cycles. The analysis demonstrates the influence of applying an increased number of wetting/drying cycles on the acceleration of the developed corrosion in the buried galvanized steel coupons. The study examines changes in the steel geometry represented by thickness loss and the accompanied deterioration of the mechanical properties such as tensile strength, hardness, and ductility over relatively short periods of time. It was observed that corrosion was insignificant as long as the zinc coating of the galvanized steel lasted. However, when the zinc was almost fully depleted, the bare steel was directly subjected to the surrounding corrosive environment, causing greater corrosion damage during subsequent wetting/drying cycles. Based on four standard mathematical models, the paper also presents approximate average corrosion predictions for bare steel in the galvanized coupons, to assess the impact of potential damage due to corrosion and determine essential rehabilitation measures. [ABSTRACT FROM AUTHOR]

This paper deals with the evaluation of the surface of structural steel whose samples were deliberately contaminated with transparent spray primer, adhesive label glue, and welding sprays prior to hot-dip galvanizing. The galvanized samples were studied by optical microscopy, GDOES, adhesion tests, and condensation humidity tests. The effect of surface contamination on the quality of the zinc coating was found to be significant. In some cases, the zinc coating is damaged (after contamination with welding sprays), in others, it is completely absent (after contamination with spray primer or adhesive label glue). [ABSTRACT FROM AUTHOR]

Post-mechanical plating heat treatment induces the formation of an iron–zinc (Fe-Zn) rich intermetallic layer between Zn and ZnSn coatings and the substrate. Despite increased outer coating porosity, the corrosion resistance of Zn- and ZnSn-coated steels significantly improves after heat treatment, attributed to the formation of intermetallic phases. This study employs small- and ultra-small-angle neutron scattering (SANS and USANS) to investigate the behavior of mechanically plated Zn and ZnSn coatings pre- and post-heat treatment. In the presence of a relatively thick steel substrate, strong multiple scattering occurs. However, by identifying a specific high Q-range region where multiple scattering is negligible, we reveal small but significant differences. Porod's slopes, denoted as 'n', are calculated for uncoated steel, and Zn- and ZnSn-coated steels (both with and without heat treatment). These slope values reflect contributions from different interfaces on the particles' surface roughness. Despite the challenges of multiple scattering, our findings offer valuable insights into coatings' behavior. The study lays a foundation for future investigations into coating behavior using SANS/USANS techniques. [ABSTRACT FROM AUTHOR]

To prevent corrosion of steel products, the steel industry often relies on Al-Zn based alloy coatings, applied through hot-dip coating technology. Despite this, a long-standing problem in the galvanizing industry involves the formation of Fe-based intermetallic compounds (IMCs) in the Al-Zn coating bath, caused by iron dissolution from steel products. Such IMCs are the primary source of dross formation in the Al-Zn bath, which inevitably leads to metal spot defects in the coated steel products and bottom dross build-up in the Al-Zn bath. The present research aims to investigate the mechanism of Fe transformation into IMCs. To achieve this, Fe saturated and unsaturated Al-Zn alloys were doped with low carbon steel at a temperature of 600 °C. The samples were collected at regular intervals and quenched in water. The optical microscopy (OM) and scanning electron microscopy (SEM) with energy dispersive x-ray spectroscopy (EDS) were used to study the transformation of steel strips into Fe-IMCs particles in molten Al-Zn alloys. The study findings suggest that the Fe transformation into Fe-IMCs is a complex process, where the steel strip surface is initially oxidized, and Al5Fe2 and Al3Fe are formed, which finally transform into Al8Fe2Si(Zn) (τ5c) IMCs particles. These results can assist galvanizers in understanding formation of Fe-IMCs and bottom dross build up in the costing pots.

Didactic educational opportunities in traditional domains of knowledge can be victims of slow penetration of new ideas and concepts. This is particularly manifested in areas such as electrochemistry that have for long remained supportive subjects rather than main courses. Although electrochemistry is pushing the technological envelope in no uncertain measure, the latest being its foray into the nanodomain, the subject remains largely unheralded. The conspicuous absence of a formal educational base for electrochemistry can potentially lead to loss of institutional knowledge, pulling the subject back further. Electrochemistry being a connector of disparate but key subject areas, there is an urgent need to produce a genre of flag bearers in the form of educators, scientists, engineers, technology leaders, and innovators who can steer the course of civilization through electrochemistry. Our thesis in this perspective is the need to position electrochemistry as a central subject. We also discuss challenges in teaching it and possible ways to surmount them. [ABSTRACT FROM AUTHOR]

Commercial harvesting of snow crabs (Chionoecetes opilio) began in Newfoundland and Labrador, Canada, in 1967. Today, the fishery consists of 2188 active fishing licenses and has grown into the province's most economically valuable fishery. Snow crabs are captured using conical traps consisting of a mild carbon steel frame, hard plastic entry funnel and a jacket of polyethylene netting. The frames of these traps corrode over time, which is expedited by being deployed in marine environments and stored on land near the ocean when not in use. As a result, there is interest within the community to increase the longevity of crab traps. One solution is to galvanize the steel frames prior to installing the funnel and netting. However, before harvesters transition to galvanized traps, two questions must be answered. Will the use of galvanized steel negatively impact catch rates? Will the life cycle of a crab trap be extended sufficiently to justify the additional cost of galvanizing? This study employed a generalized linear mixed model to evaluate the catch of legal-sized male crabs (CPUE) during the commercial fishery as a function of three trap frame treatments (old traditional, new traditional and new galvanized). We also assessed the economic viability of galvanizing trap frames by evaluating the life cycle cost (LCC) of traditional and galvanized traps to the harvester. The LCC was calculated over a range of inflation (0–6%) and discount (3–20%) rates. Our results found no significant difference in CPUE between new traps (traditional vs. galvanized) and concluded that except during instances of very high discount rates (12.9–19.9%), it is economically favourable to galvanize crab trap frames. [ABSTRACT FROM AUTHOR]

Zn-Al-Mg-Si coatings are an excellent alternative to conventional hot-dip galvanizing coatings. Their high corrosion resistance in corrosive environments containing chlorides and CO2 is well recognized. But sulfur dioxide is also an important stimulator of corrosion in the atmospheric environment. This article presents the results of microstructure (SEM/EDS/XRD) and corrosion behavior tests of Zn-Al-Mg-Si coatings obtained by a double hot-dip method on HSLA steel. The corrosion resistance of the coatings was determined in the sulfur dioxide test with general condensation of moisture (EN ISO 6988). In the corrosion test, Zn-Al-Mg-Si coatings showed twofold smaller weight loss compared to conventional hot-dip zinc coatings. It was found that the corrosion behavior of coatings was influenced by the structural components revealed in the outer layer: Al-rich dendritic and interdendritic areas with Zn/MgZn2 eutectic, MgZn2 intermetallic and Si precipitates and their electrochemical nature. The increase in corrosion resistance was caused by the formation of beneficial corrosion products: layered double hydroxides (LDHs) based on divalent Mg2+ and Zn2+ cations, trivalent Al3+ cations and SO42− anions, and zinc hydroxysulfate—Zn4SO4(OH)6∙5H2O. The presence of Si precipitates could cause pitting corrosion of coatings. [ABSTRACT FROM AUTHOR]

During hot-dip galvanization, wastes such as bottom dross, zinc ash, spent pre-treatment solutions, and galvanizing flue dust (GFD) are generated. In scientific publications, research devoted to GFD waste recycling is absent, and companies generating this waste require a solution to this complex problem. GFD is often landfilled in hazardous waste landfills. However, it is possible to process this waste hydrometallurgically, where GFD is first leached, the solution is refined, and finally, zinc metal is obtained by electrowinning. During specific environmentally friendly leaching, not all solid GFD is dissolved, and the aim of this study is to process the remaining solid GFD residue. The analysis shows that the GFD residue material mainly contains zinc (42.46%) in the form of oxides, but there is also a small amount of polluting elements such as Al, Fe, and Pb. This study examines the leaching of the samples in HCl and H2SO4 under different conditions with the aim of obtaining a solution with a high concentration and high leaching efficiency of zinc. The L/S ratio of 3, 4 M H2SO4, and ambient temperature proved to be optimal for the leaching of the GFD residue, where 96.24% of zinc was leached out, which represents a zinc concentration of 136.532 g/L. [ABSTRACT FROM AUTHOR]

• Desirable inhibition of browning rate and enzyme (PPO/POD) activities were found with the progression of 15 days of storage under 4 ± 1 ℃. • Findings suggest herbal extract coating can be an effective alternative to chemical coating due to its increased antioxidant activity. • 80 and 60 % inhibition of phenolase and peroxidase were observed in coated pear slices in comparison with control pear slices. • C. sinensis extract was better among all applied herbs in inhibiting discoloration enzymes and showed a lower browning index. The main objective of the research study is to evaluate the effect of herbs (O. basilicum, O. vulgare, C. sinensis) extract-coated pear slices on its physiochemical quality attributes, discoloration rate, and browning enzyme activity in comparison with chemical (ascorbic acid) coated pear slices over 15 days at 4 ± 1 ℃. A significant difference (p < 0.05) between herbs and ascorbic acid-coated pear slices was obtained in terms of physiochemical quality attributes, whereby the highest variation was obtained in uncoated pear slices (control) and the least variation was observed in herbs-coated pear slices, more specifically C. sinensis spray, and dip (6 min) extract showed the highest inhibition of PPO/POD activity and the minimum browning index was noticeable throughout 15 days of storage. These findings showed that herbal extract coating application to fresh-cut pears might be a desirable strategy to alleviate discoloration, also considered to be an effective alternative to chemical coating. [ABSTRACT FROM AUTHOR]

The minimization of unwanted dross build-up formation on the sink rolls in continuous hot-dip galvanizing lines is a key goal of the industry. In this study, the CFD multi-physics modeling of the surface reaction kinetics for dross build-up growth and the coupling to the mass transfer is the basis for the evaluation of relevant process parameters. The results of a virtual Design of Experiments were processed by neural network approaches, as well as linear regression modeling to build a surrogate process model. It was found that the bath Al concentration has the highest effect (> 80 pct) on the dross build-up rate on the sink rolls. Operating the zinc bath at higher Al concentrations decreases the dross build-up reaction rate. Furthermore, it was found by the CFD multi-physics model that the local dross build-up rate increases toward the edges of the roll grooves which might lead to the occurrence of strip surface defects. [ABSTRACT FROM AUTHOR]

Direct use of metals as battery anodes could significantly boost the energy density, but suffers from limited cycling. To make the batteries more sustainable, one strategy is mitigating the propensity for metals to form random morphology during plating through orientation regulation, e.g., hexagonal Zn platelets locked horizontally by epitaxial electrodeposition or vertically aligned through Zn/electrolyte interface modulation. Current strategies center around obtaining (002) faceted deposition due to its minimum surface energy. Here, benefiting from the capability of preparing a library of faceted monocrystalline Zn anodes and controlling the orientation of Zn platelet deposits, we challenge this conventional belief. We show that while monocrystalline (002) faceted Zn electrode with horizontal epitaxy indeed promises the highest critical current density, the (100) faceted electrode with vertically aligned deposits is the most important one in suppressing Zn metal corrosion and promising the best reversibility. Such uniqueness results from the lowest electrochemical surface area of (100) faceted electrode, which intrinsically builds upon the surface atom diffusion barrier and the orientation of the pallets. These new findings based on monocrystalline anodes advance the fundamental understanding of electrodeposition process for sustainable metal batteries and provide a paradigm to explore the processing-structure-property relationships of metal electrodes. [ABSTRACT FROM AUTHOR]

This work aims at understanding the formation of a beneficial thin continuous aluminum (Al)-rich interfacial layer with uniform distribution of fine equiaxed Fe-Al crystals formed at the substrate/coating interface during the initial stages of interfacial reactions as well as hindrance of Fe dissolution in Zn layer as soon as copper (Cu) pre-coated high-strength steel substrate is immersed into the molten zinc (Zn) bath containing 0.2 wt.% Al. Pre-coated Cu does not allow the immediate interaction and interdiffusion of Fe and Zn because of the positive heat of mixing between Fe and Cu. As the Cu dissolves in liquid Zn, counter-diffusion of Al and Zn toward the steel interface allows Fe to react with Al and Zn forming the thin Fe-Al inhibition layer with finer equiaxed grains. Moreover, dissolved Cu in the Zn layer would also prevent Fe diffusion in Zn in the time span during dipping, which is beneficial. Atom probe tomography (APT) analysis at the substrate/coating interface location reveals the presence of 56.22 ± 1.36 at.% Al, 35.01 ± 1.31 at.% Fe, 6.33 ± 0.66 at.% Zn, and 0.032 ± 0.01 at.% Cu, similar to the intermetallic compound of Fe2Al(5-x)Znx, as well Cu in the Zn layer supporting the above reasoning. [ABSTRACT FROM AUTHOR]

We investigated the influence of steel surface properties on the wettability of zinc (Zn). Our main objective is to address the selective oxidation of solute alloying elements and enhance the wetting behavior of Zn on advanced high strength steel (AHSS) by employing an aluminum (Al) interlayer through the physical vapor deposition technique. The deposition of an Al interlayer resulted in a decrease in contact angle and an increase in spread width as the molten Zn interacted with the Al interlay on the steel substrate. Importantly, the incorporation of an Al interlayer demonstrated a significant improvement in wettability by substantially increasing the work of adhesion compared to the uncoated AHSS substrate. [ABSTRACT FROM AUTHOR]

Bath galvanized substructures for rear‐ventilated façades – part 1 Thin‐walled steel components (0.8–2.5 mm) for substructures according to DIN 18516‐1 can be produced using galvanisation. Brackets and support profiles remain warp‐free, the thickness of the zinc layer is above the standard acc. to DIN EN ISO 1461. Flanging on the edges of the holes in the brackets and lateral edging increase the load‐bearing capacity, as do increasing sheet thicknesses. Load‐bearing profiles are also strengthened by lateral edging; U‐ and hat‐profiles are on top. Experimental tests in the climatic chamber revealed a gradation of the perforated brackets; the most favourable design is the bracket with three slotted holes. Thermal and mechanical tests have proven that galvanized components represent a static, thermal and economical alternative to commercially available substructure systems. [ABSTRACT FROM AUTHOR]

Given impending regulations, a study of community water systems found challenges in defining, identifying, and funding remediation of the galvanized pipe associated with lead service lines. [ABSTRACT FROM AUTHOR]

Chemical residues from aquaculture, especially heavy metals, are harmful to environment. The present study assessed the seasonal dynamics and potential toxic effects of heavy metal accumulation (Cr, Cu, Zn, and Pb) in lake sediments within the impact zone of the trout cage farm (Lake Ladoga, Russia). The tasks included the layer-by-layer analysis of total content of the heavy metals and their labile forms in sediment cores collected in the winter and autumn seasons. Four sites located directly next to the cages and three reference sites (150, 600, and 1,000 m from the farm) were studied. Sediments cores collected using gravity corer were analyzed for total content analysis, where sediment samples were decomposed with strong acids (HClO4, HF, HCl, and HNO3), and the labile forms were extracted by ammonium acetate. The results showed that sediments under fish cages were significantly polluted by Zn and Cu especially towards the end of the active feeding period (autumn), thus potentially increasing sediment toxicity. Therefore, Zn and Cu can be utilized as geochemical markers for assessing the thickness of the accumulated contaminated sediment layer in the impact zone of cage farms. Pollution of the sediments by heavy metals is local and limited to the studied bay. Hence, there is no risk of secondary pollution of the water column according to the RAC index. However, the absolute content (mg·kg-1) of labile Zn is much higher under the cage than at reference sites. [ABSTRACT FROM AUTHOR]

The elimination and retrieval of slag produced during the hot-dip galvanizing process are crucial in reducing plating defects and enhancing economic efficiency. Hot-dip galvanizing slag can be separated and purified efficiently by using graphite carbon felt filtration in a supergravity field. The effects of the gravity coefficient (G), separation temperature (T), and separation time (t) on the separation efficiency were investigated. Under the optimal conditions as G = 300, T = 460 °C, and t = 120 s, these conditions yielded filtered zinc with 0.022 wt% Fe and 1.097 wt% Al. The separation efficiencies achieved were 87% for the acquisition ratio of filtered zinc (AZn), 93.67% for the recovery ratio of zinc (RZn), and 96.01% for the loss ratio of iron (LFe). Based on these laboratory findings, an amplified centrifugal separation apparatus was conceptually designed for future online separation and recycle of zinc slag on an engineering scale. The filtered zinc obtained from this apparatus contained 0.027 wt% Fe and 1.844 wt% Al, while the recovery ratio of zinc (RZn) and the loss ratio of iron (LFe) achieved 85.97% and 95.47%, respectively. [ABSTRACT FROM AUTHOR]

Thin-walled galvanized helical corrugated steel tubes (HCSTs) filled with concrete are promising composite members, consisting of concrete, an anti-corrosion shell, and a multifunctional exterior corrugated steel tube. To investigate the synergistic working mechanism of concrete-filled HCSTs (CFHCSTs), six specimens were designed for axial compression tests, with the inner diameter of the column and the volumetric steel ratios of the longitudinal reinforcement as the variation parameters. The results show that HCSTs can better confine the concrete core and increase its strength. The failure mode of HCSTs is significantly influenced by the column's diameter, and those with a smaller diameter are prone to slide failure and lock seam tearing. The strains and stresses on HCSTs are discussed in detail to elucidate the confinement effect. This paper proposes a suitable design method to predict the ultimate axial compression load capacity of CFHCST columns based on early studies on steel tube-confined concrete. [ABSTRACT FROM AUTHOR]