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The cost for repair and maintenance the failure parts due to corrosion has a raised worldwide influence. The steel B500B have been coated with hot dip galvanizing, to offer stability and corrosion protection, via the deposition1 of a thin layers of zinc on the steel by submersion in a molten bath. The mechanical and the fatigue behaviour have been conducting, also scanning electron microscope SEM have been examined after coating the steel, to increase the understanding of the damage and failure of a structural steel, in order to experience such treatment. The rotating bending with R#x003D;-1 have been tested to get the fatigue behaviour. Relations that have been put forward in attempts to mathematically describe the cycle fatigue range of the S#x2013;N curve (by Basquin) are compared to the experimental data. The power low relation was found agree with results. [ABSTRACT FROM AUTHOR]

Galvanized Zn or it alloys was commonly used to protect the steel structure from corrosion. However, under certain extreme conditions such as the marine environment, the performance of Zn galvanized would deteriorate. This paper reported the performance of potential ZnAl galvanized with incorporation of WO3 and Ag nanoparticles through electrochemical impedance spectroscopy. The morphology of the coating was performed using scanning electron microscope. The analysis indicates that the presence of WO3 and Ag nanoparticles increase the corrosion resistance under 3.5% NaCl solution as compared to bare ZnAl coating. The capability of WO3 to create hydrophobic surface coating was supported by water contact angle analysis. The addition of WO3 and Ag nanoparticle in ZnAl coating has decrease the surface reaction to prevent steel structure from enduring corrosion reaction. [ABSTRACT FROM AUTHOR]

It was found that during the electrolysis of zinc electrolyte, which contains a colloidal solution of nanodiamonds, a coating is formed on the steel surface by co-deposition of nanodiamonds with zinc ions. The dependence of the friction coefficient in the coating - steel triboconjugation on the concentration of nanodiamonds in the coating has been determined. In particular, the concentration of 5% nanodiamonds makes it possible to achieve the greatest (up to 0.09) decrease in the friction coefficient, while with a concentration of 0.5% nanodiamonds, the friction coefficient is 45% higher. It has been experimentally confirmed that the wear resistance of the coating monotonically increases with increasing concentration from 1% to 7%, which is due to the presence of functional groups in the hybrid zone of nanodiamonds and the passivation of interacting uncompensated σ-bonds during friction, which reduces the adhesion between tribo-conjugated surfaces. [ABSTRACT FROM AUTHOR]

The objectives of this research were to determine the optimal values of the dipping temperature, the length of dipping time, and the dipping tilt angle in the hot-dip galvanizing process, which influence the thickness of the galvanized angle bar steel product, in accordance with the thickness standard of ISO 1461. This research used the Taguchi technique with an experimental design. The testing and validation stages were carried out based on the average temperature value, S/N ratio, and ANOVA test. The response factor is the galvanic thickness. Control factors consist of dipping temperature, length of dipping time, and dipping tilt angle of the steel during the galvanizing process. The results showed that the main factors that influence the galvanized thickness are the length of dipping time factor (B), which contributes to the difference in the S/N ratio of 85.94118%, and the dipping tilt angle factor (C), which contributes to changes in the S/N ratio of 13.60962%. The optimal value of the dipping temperature is 448°C, the length of the dipping time is 8 minutes, and the dipping tilt angle is 45°. [ABSTRACT FROM AUTHOR]

The inadequacy of sustainable energy is endlessly posing major challenges globally. The issue of energy optimisation is indispensable for manufacturing sector, particularly for a hot-dip galvanising process where galvanising furnaces are the significant energy users. This study is aimed at comparative analysis of specific energy consumption and energy consumption benchmarking in four galvanising plants with the view to necessitate the identification of best practices. Energy baselines were used as quantitative reference points to compare energy performance indicators and quantify fluctuations in energy performance during the baseline and reporting periods. A quantitative analysis was also conducted to benchmark four galvanising facilities on factors that included the electricity/zinc ratio, electricity /dips ratio and product tonnage/zinc used ratio. The results revealed improved performance for plant 4 over time relative to the baseline consumption when compared to plants 1, 2 and 3. Plant 4 also outperformed other facilities after the energy efficiency interventions in terms of electricity/zinc ratio and electricity/ product tonnage ratio. Given the disparity between the results of specific energy consumption (SEC) for the four plants, it was concluded that SEC alone should not be used as an energy performance indicator. [ABSTRACT FROM AUTHOR]

Zinc coated steels are widely used in automotive and construction industries, due to their superior corrosion resistance compared to uncoated steels. Hot dip galvanizing is one of the most economically viable zinc coating techniques, developed over 200 years ago. However, modification in the zinc bath composition, more advanced structural designs, along with demanding service conditions have resulted in increased instances of failure of galvanized steels. Failure of galvanized steels can take place by several mechanisms such as liquid metal embrittlement (LME), hydrogen embrittlement (HE), distortion cracking and strain age embrittlement. For failure analysis to be carried out, it is important that the background and service history of any component is thoroughly understood. In this respect, the various mechanisms and the factors affecting them during and after galvanizing are discussed in this paper. The numerous factors are broadly categorized as (i) pre-treatment and galvanizing process, (ii) properties of the steel to be coated, (iii) properties of the galvanizing bath, (iv) galvanizing process parameters, (v) fabrication process and (v) service condition. Several experimental results and case studies are presented to understand the embrittlement and fracture of galvanized steels. [ABSTRACT FROM AUTHOR]

Nowadays, steel constructions and their elements are used for their properties. One of their advantages is, for example, their low weight in comparison with their load capacity. Also, quick assembly is one of their advantages. On the other hand, there are disadvantages which are associated with changes of properties under thermal stress. There are no significant changes up to a temperature of 350°C, but steel loses their load capacity between 500-700 °C [1], [2]. Because of that, in many cases these constructions are treated with the fire-retardant coatings. Fire-retardant coatings are used for their capability to increase their resistance to the effects of heat. For example, Lucherini [3] and his team performed an experimental study with thin intumescent coatings. They monitored the beginning of the coating’s reaction depending on the temperature. In many cases, steel construction is treated only with anticorrosive coatings. An anticorrosive coating protects constructions against the adverse effects of the environment in which they occur. Anticorrosive systems were tested as a fire protection coating by Mensinger and Gaigl [4], [5]. In this case, hot dip galvanized steel elements were exposed to thermal heat. The results proved the improved behaviour of these hot dip galvanized steel elements in comparison with untreated elements or elements with a layer of rust. In our experimental measurement, steel plates were treated with surface treatments according to the manufacturer’s instructions. Several types of coatings in shades of black and white were used for this experiment. Treated steel plates were exposed to different level of heat radiation for 30 minutes. The effects of the thermal load by a radiation component on these selected anticorrosive coatings and steel elements were monitored and evaluated. The temperature and heat flux density was monitored and also visual damage and paint compactness was evaluated. The results proved the different resistance of individual types of paints [6]. Samples of used coatings were prepared and subsequently subjected to thermal analysis for a comprehensive evaluation of the resistance. Thermal analysis is used for monitored processes, for example oxidation, dehydration or other. These processes occur when the test sample is heated or cooled. The thermal analysis is a set of methods which monitored changes in mass, release, or consumption of heat, and other areas, such as a volume changes or the evolution/absorption of gases [7]. Weight loss according to time and increasing temperature was monitored in a thermogravimetric analysis, but a differential scanning calorimetry analysis was also performed. The results confirmed the greatest resistance from a paint named Hempathane. This coating also showed the greatest visual compactness and resistance during the heat load. Depending on the extent of the damage, the level of the thermal load of the steel construction could be assessed in practice. [ABSTRACT FROM AUTHOR]

While the coffee house as a space of political deliberation has been a common feature across the globe, there are few historical cases in which one can analyze the role of such face to face political deliberation under totalitarian moments in heretofore democratic states. Of the analogous cases of democratic reversal, India is one of the most important and underresearched. In 1975, then Prime Minister Indira Gandhi was convicted of corrupt election practices. Rather than concede to the high court ruling, she suspended the constitution and installed herself as India's sole political authority. The Indian Coffee House in New Delhi became the key site of resistance to the Emergency (1975-77). The totalitarian moment pushed contentious politics into the Coffee House, initially galvanizing it: even the older members of Indira Gandhi's Congress Party, who were active participants in India's Freedom Movement, were key participants in coffee house deliberations. Eventually, however, Indian Coffee House was bulldozed and political deliberation crushed. The space of the coffee house may foster political deliberation among different viewpoints, but when interaction is concentrated in one such space, it becomes easier for the state and its agents to suppress oppositional politics, and more difficult for both establishment and oppositional politics themselves to retain a diversified public sphere character. While coffee houses and analogous institutions are not adequate substitutes for other forms of democratic politics, therefore, they can encourage expression when other avenues are closed off, and nourish the memory of a democratic political culture for the future. [ABSTRACT FROM AUTHOR]

Modified Turkevich synthesis protocol has been effectively utilized in the mechanistic formation of monodisperse hollow gold nanostructures, by the careful addition of Au3+-ions to the as-prepared Ag nanoparticles, thus initiating the sequential galvanic replacement process in a cohesive manner. The cavity aspect ratio of hollow Au nanostructures were further tuned by optimal NaCl addition to the reaction mixture. The structure-property functional relationship of these artificial metal nanostructures were systematically studied using optical absorption and TEM measurements. [ABSTRACT FROM AUTHOR]

Robots are a distributive technology that promotes change. Human-Robot Interaction is an emerging field that has exciting prospects for widespread transformation. Today, embedding social intelligence into human-robot interaction design is a moonshot. Moonshots can boost science and engineering by galvanizing and incentivizing research communities and industry in the pursuit of impossible challenges to accelerate progress and scale impact. Social intelligence is all about power and influence; privacy and trust; ethical decisions and happiness. What if, robots could take the initiative and purposefully persuade you to believe something new. HRI with social intelligence has the potential to create breakthrough insights and that will energize the reimagination of how humans and robots will collaborate in business and society. [ABSTRACT FROM AUTHOR]

Zinc coating weight control is one of the most critical issues for continuous galvanizing line. The process has the characteristic of variable-time large time delay, nonlinear, multivariable. It can result in seriously coating weight error and non-uniform coating. We develop a control system, which can automatically control the air knives pressure and its position to give a constant and uniform zinc coating, in accordance with customer-order specification through an auto-adaptive empirical model-based feed forward adaptive controller, and two model-free adaptive feedback controllers . The proposed models with controller were applied to continuous galvanizing line (CGL) at Angang Steel Works. By the production results, the precise and stability of the control model reduces over-coating weight and improves coating uniform. The product for this hot dip galvanizing line does not only satisfy the customers' quality requirement but also save the zinc consumption. [ABSTRACT FROM AUTHOR]

A wireless surface acoustic wave (SAW) transponder system was developed to monitor the temperature of rotating rollers of an electrolytic galvanizing plant. The exact knowledge of this temperature could be an important process parameter used for an in-line quality control of the galvanized sheets. The rollers as well as the transponders are exposed to hot sulfuric acid, and rotate with a maximum tangential velocity of 2 m/s. [ABSTRACT FROM PUBLISHER]

The starting point for optimization of environmental pollution prevention and occupational diseases in an organization is the risk assessment of that system. Risk assessment involves the identifying all risk factors from the analyzed system and the quantifying their dimension based on the combination of two parameters: event severity and the probability that it occurs. The present paper emphasizes this aspect and presents some methods used for risk assessment and the steps to establish the risk levels. As example, the environmental risk assessment in a galvanizing unit is presented. The technology of obtaining zinc coatings steel, using a classic cleaning of surface, includes the following polluting operations: chemical degreasing, pickling, fluxing, preheating drying, hot dip galvanizing, cooling, final treatment. For the environmental risk assessment in the hot-dip galvanizing unit, the main identified hazards were established the severity class, the probability class and the resulted risk level. It also presents technological and organizational measures to minimize environmental risk in the galvanizing of steel sheets. [ABSTRACT FROM AUTHOR]

Steel is one of the most recycled materials in the world and modern, as-rolled structural sections are produced with varying combinations of alloy metals to fulfill many purposes. It is very important to specify the right requirements according to the material properties, ductility, toughness, through-thickness properties, weldability, and appearance of galvanized and dulled finished. Surface preparation is the most critical step in the application of any coating. It is essential for hot-dip galvanizing process, namely the iron-zinc metallurgical reaction, that the steel surface to be perfectly cleaned, i.e. free from grease, rust and scale. Any inadequacies in surface preparation will immediately be apparent when the steel is withdrawn from the molten zinc. It is very common that lattice steel towers are made of galvanized steel and sometimes dulled by a passivation process after hot dip galvanizing steel members. Passivation is a process that creates a protective layer on the surface, which may last about six weeks before being consumed. At that time, galvanized steel will begin to weather naturally. Most steels can generally be satisfactorily coated through a hot dip galvanizing process, however, reactive elements in the steel, silicon (Si) and phosphorus (P) in particular, can affect the appearance and thickness of the coating. Steel with low silicon content can provide a more consistent quality of coating in terms of coating thickness and smoothness of the galvanized coating. Where a long term dull appearances are important, steels with silicon content in the range of 0.04 to 0.15 and above 0.22 percent by weight should be avoided. This paper addresses the challenges in hot dip galvanizing process for reactive steel and possible discoloration phenomenon due to Silicon Effect Color Transformation (SECT) on galvanized steel members for lattice transmission tower structures. It also gives the preliminary guidance to utilize some specialized techniques to achieve the desired galvanizing and dulling finish. [ABSTRACT FROM PUBLISHER]

Hot-dipping galvanizing process is a widely used and efficient way to protect steel from corrosion. We propose to master the microstructure of zinc grains by investigating the relevant process parameters. In order to improve the texture of this coating, we model grain nucleation and growth processes and simulate the zinc solid phase development. A coupling scheme model has been applied with this aim. This model improves a previous two-dimensional model of the solidification process. It couples a cellular automaton (CA) approach and a finite element (FE) method. CA grid and FE mesh are superimposed on the same domain. The grain development is simulated at the micro-scale based on the CA grid. A nucleation law is defined using a Gaussian probability and a random set of nucleating cells. A crystallographic orientation is defined for each one with a choice of Euler's angle (Ψ,θ,[lowercase_phi_synonym]). A small growing shape is then associated to each cell in the mushy domain and a dendrite tip kinetics is defined using the model of Kurz [2]. The six directions of basal plane and the two perpendicular directions develop in each mushy cell. During each time step, cell temperature and solid fraction are then determined at micro-scale using the enthalpy conservation relation and variations are reassigned at macro-scale. This coupling scheme model enables to simulate the three-dimensional growing kinetics of the zinc grain in a two-dimensional approach. Grain structure evolutions for various cooling times have been simulated. Final grain structure has been compared to EBSD measurements. We show that the preferentially growth of dendrite arms in the basal plane of zinc grains is correctly predicted. The described coupling scheme model could be applied for simulated other product or manufacturing processes. It constitutes an approach gathering both micro and macro scale models. [ABSTRACT FROM AUTHOR]

The cases with the samples with not covered Fe-Zn alloy areas appear during zinc process at the factory because lighter method was analyzed in this work, that can help the factory. After this experiment, not covered areas of samples can be adjusted dipping them into fliux and the Zn bath again for 1 min. [ABSTRACT FROM AUTHOR]

The steel wire samples are hot-dip-galvanized. The zinc coating is preformed using the standard method. To recognize the behavior of the zinc coated steel wire during the submission to deformation, the wire samples are drawn on a machine designed for this aim and then investigated. In this research is represented the phase structure of the zinc coated samples. Afterwards the thickness of the layer and the hardness of the hot-dip galvanized steel depending on the drawing is represented. [ABSTRACT FROM AUTHOR]

Fault detection and diagnosis is an important problem in process engineering. Process equipments are subject to malfunctions during operation. Galvanized steel is a value added product, furnishing effective performance by combining the corrosion resistance of zinc with the strength and formability of steel. Fault detection and diagnosis is an important problem in continuous hot dip galvanizing and the increasingly stringent quality requirements in automotive industry has also demanded ongoing efforts in process control to make the process more robust. When faults occur, they change the relationship among these observed variables. This work compares different statistical regression models proposed in the literature for estimating the quality of galvanized steel coils on the basis of short time histories. Data for 26 batches were available. Five variables were selected for monitoring the process: the steel strip velocity, four bath temperatures and bath level. The entire data consisting of 48 galvanized steel coils was divided into sets. The first training data set was 25 conforming coils and the second data set was 23 nonconforming coils. Logistic regression is a modeling tool in which the dependent variable is categorical. In most applications, the dependent variable is binary. The results show that the logistic generalized linear models do provide good estimates of quality coils and can be useful for quality control in manufacturing process. [ABSTRACT FROM AUTHOR]

In this paper, a kind of automatic hot-dip galvanizing device for small components is design in order to solve the problem of highly dependence on complex artificial operations with labor intensive and difficult control of the coating often encountered during the production process of the hot-dip galvanizing in the past. By comparing and analyzing two different design schemes of mechanisms, a better scheme is obtained. A three dimensional model was made and the corresponding motion was simulated in the design of automatic hot galvanizing device with assistance of the software Solid Edge. It is found that the device can make a continuous hot-dip galvanizing for the varieties of small components. [ABSTRACT FROM PUBLISHER]

Platinum nanoparticles were formed at the surface of the poly (perfluorosulfonic) acid membrane (Nafion-117) by the galvanic reaction of PtCl62- ions with Ag nanoparticles positioned near the surface of the membrane. The reduction with BH4- ions produced Ag nanoparticles (15±4 nm size) mostly positioned near the surface of membrane due to Donnan exclusion of co-ions (BH4-). Energy Dispersive X-ray Fluorescence (EDXRF) analysis of the membrane indicated that galvanic reaction proceeded quantitatively. Transmission Electron Microscopy (TEM) of the cross-sections of membrane samples indicated that the spherical Pt nanoparticles having size 2 to 8 nm were mostly located near the surface of the membrane. The positioning of Pt nanoparticles at surface of the membrane is important for using nano-composite in catalytical application. [ABSTRACT FROM AUTHOR]

A usual practice during zinc hot-dip galvanizing is the addition of nickel in the liquid zinc which is used to inhibit the Sandelin effect. Its action is due to the fact that the ζ (zeta) phase of the Fe-Zn system is replaced by the Τ (tau) phase of the Fe-Zn-Ni system. In the present work an attempt is made to explain the formation of the Τ phase with thermodynamics. For this reason the Gibbs free energy changes for Τ and ζ phases were calculated. The excess free energy for the system was calculated with the Redlich-Kister polyonyme. From this calculation it was deduced that the Gibbs energy change for the tau phase is negative. As a result its formation is spontaneous. [ABSTRACT FROM AUTHOR]

The Rashba effect, whose experimental access is usually masked by the Dresselhaus effect, allows manipulation of spins in semiconductor spintronics. Based on the far-infrared radiation induced spin-galvanic effect, we present a unique way to separate both types of spin-orbit coupling. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

Zinc hot-dip galvanizing is an effective method for the corrosion protection of ferrous materials. A way of improving the results is through the addition of various elements in the zinc melt. In the present work the effect of Ni, Bi, Cr, Mn, Se and Si at concentration of 0.5 or 1.5 wt.% was examined. Coupons of carbon steel St-37 were coated with zinc containing the above-mentioned elements and were exposed in a Salt Spray Chamber (SSC). The micro structure of these coatings was examined with SEM and XRD. In every case the usual morphology was observed, while differences at the thickness and the crystal size of each layer were induced. However the alloying elements were present in the coating affecting its reactivity and, at least in the case of Mn and Cr, improving corrosion resistance. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Zinc hot-dip galvanizing is a method for protecting iron and steel against corrosion. Galvanizing with pure Zn or Zn with additions like Ni, Al, Pb and Bi has been extensively studied, but there is a lack of scientific information about other additions. The present work examines the effect of a 0.5 wt% Ti addition in the Zn melt. The samples were exposed to accelerated corrosion in a salt spray chamber (SSC). The microstructure and chemical composition of the coatings were determined by Optical Microscopy, XRD and SEM associated with an EDS Analyzer. The results indicate that the coatings have a typical morphology, while Zn-Ti phases were also detected. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]