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Hot-dip galvanizing is a defensive layer technique widely use to prevent corrosion damage in steel structure. There have been many reported points in which cracks have formed in steel during the process, and root causes of these cracks remain poorly understood. The investigation in the mechanical and fatigue strength of uncoated and coated steel B500B with hot-dip galvanizing HDG have been experimentally examined in an earlier study, the steel B500B was coated with hot dip galvanizing according to ASTM A123 have been used, more investigation needs to cover such subject, for wide knowledge in the fatigue failure of such treated steel due to endurance limit up to 107 cycles according to ASTM (E8/E8M−16). The numerical simulation and scanning electron microscope SEM were employed as the main investigation method in this study. Examination on the surface after failure has been noticed roughness on the coated region, which is the sources of cracks initiation and stress concentration. In addition, the results of numerical analysis, verified that existence of coating imperfections, imposed a significant stress concentration leading to an effective reduction of the expected life time of the sample. [ABSTRACT FROM AUTHOR]

Welding on plate is widely used in the industrial world, especially in the manufacture of construction. Recently, plate welding has been developed using a different type of material and it is called dissimilar welding. Stainless steel is a material which usually used to get its rust-resistant properties, but the use of stainless steel as a whole will cause a large cost due to its high price. Another rust-resistant material that can be used as another option is galvanized steel. However, the use of galvanized steel is not very efficient because it is heavier than stainless steel. Therefore, in this study, stainless steel 201 and galvanized steel were combined using MIG (Metal Inert Gas) welding. This research aimed to investigate maximum load on dissimilar joint (SS 201 dan galvanized steel). The parameters used are gas pressure, welding wire speed and welding speed with each parameter using 3 levels. The tensile test results showed that the highest tensile strength is 1.66 kN and the lowest tensile strength is 1.44 kN. [ABSTRACT FROM AUTHOR]

Various steel components of rectangular hollow section (RHS) are of common use in many transport industries. Study of three point bending behavior is a special requirement for these RHS steels. In the present work, modeling of three point bending behavior for RHS of mild steel and galvanized steel has been analyzed using the Fusion 360 CAD/CAE system and compared. RHS with cross sections of 40 mm x 50 mm having different wall thicknesses, i.e. 1.936 mm, 1.843 mm and 0.7 mm were considered for the modeling study. The effects of increasing the magnitude of load on smaller and larger faces on deflection of the RHS were analyzed. Results reveal that the bending deflection was lesser for galvanized steel specimen as compared to its mild steel counterpart for a constant RHS thickness and variable load conditions at any loading faces. In addition, increase in RHS thickness caused reduction in bending deflection, when the applied load was constant on RHS galvanized steel specimen. [ABSTRACT FROM AUTHOR]

Deep drawing is a Forming sheets metals technique that is frequently utilized due to its ability to generate a broad range of forms without flaws or Lamination that is too localized the study of the octagon shape. The purpose of this work is to evaluate the strain and thickness alteration behavior of deep drawing and to select the suitable method and thickness to create octagonal cups with dimensions (23.42×21.82 mm) and high (60mm). The octagonal cup is drawn in three steps under the impact of different forming parameters such as, the speed of punch (v=50, 200, 350 mm / min), the thickness of Blank (t= 0.7, 0.5 mm), die's wall curve radius(R cd=2 mm), galvanized steel (ASTM A653), and diameter (80mm). Numerical simulation was conducted using ANSYS Workbench 19.0 software used to carry out forming of the octagonal cup. The results have shown that the best way to make an octagonal cup is the first method where the effective strain values in the third stage are lower (7.61%) than in the second method, and the thickness is more uniform. Regarding both time and money, it is regarded as a cost-effective strategy. The maximum thinning of the thickness in the third stage is (14.422%FEA, 15.855%EXP) at the corner radius region of the cup when using the second method with the biggest speed of punch (v=350 mm / min). While the best thickness (t=0.7 mm) to make an octagonal cup for reason the effective strain values in third stage are lower (4.63%) than in the (t=0.5mm). The results have shown that experimental and numerical works agree well, with the biggest difference being 15%. [ABSTRACT FROM AUTHOR]

This study focuses on evaluating the thermal conductivity of different types of sandwich panels. The first type was a traditional sandwich panel made of two galvanized steel face sheets with a core of polyurethane foam (PSP); the second was a honeycomb sandwich panel made of two face sheets of aluminum with a structural core of polyvinyl chloride PVC tubes (HSP1); the third was (HSP1) with the thermal insulation paint coated on the two face sheets (HSP2); and the fourth was (HSP1) using polyurethane foam to fill the core cells (HSP3). The properties of heat transfer and thermal conductivity of sandwich panels were investigated. The third honeycomb sandwich panel (HSP3) has lower thermal conductivity compared to the other tested sandwich panels, with significant mechanical properties. [ABSTRACT FROM AUTHOR]

Ducts of alternative materials to galvanised steel, are widely employed in residential buildings' mechanical ventilation systems in a bid to comply with the conservation of energy regulations in circumstances that prevent the use of natural ventilation. The noise transfer predictions of systems with alternative ducts are still being based on data for galvanised steel due to the lack of acoustic performance data of alternative ventilation ducts tested in controlled conditions. To close this knowledge gap, a test rig was designed and built based on the test set up defined in ISO 7235. Alternative ventilation ducts and associated 90º bend samples were acoustically tested in controlled laboratory conditions utilising customized test rig developed to suit typically small duct profiles of alternative ventilation ducts. Test samples were tested using two methods: the substitution principle as outlined in BS EN ISO 7235 (2009) as well as applying a novel "zero substitution" conceptual approach. The preliminary results of the "zero substitution" approach tests show indication of its validity. [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]

Hot Dip Galvanizing is one of the oldest and more used methods to protect steels substrates from corrosion due to the good corrosion resistance of the Zn coatings. This work studies the effect of the addition of small amounts of Ni to hot-dip galvanizing bath on the corrosion behaviour of hot-dipped Zn rich coating using open circuit potential (OCP), electrochemical noise (ENM) and electrochemical impedance spectroscopy (EIS). The results show that the Zn-Ni coating alloys exhibit nobler potentials and low current density indicating the increase of the corrosion resistance of the sample due to the protective effect provided by the oxides formed on Zn-Ni coating alloys. However, the corrosion products allow the mass transfer of aggressive species showing a semi-infinite behaviour. The protective effect shows a relationship with the Ni amount employed. The hot-dip method for deposition of ZnNi coatings using 0.5% Ni exhibit the best performance. [ABSTRACT FROM AUTHOR]

Hot Dip Galvanizing is one of the oldest and more used methods to protect steels substrates from corrosion due to the good corrosion resistance of the Zn coatings. This work studies the effect of the addition of small amounts of Ni to hot-dip galvanizing bath on the corrosion behaviour of hot-dipped Zn rich coating using open circuit potential (OCP), electrochemical noise (ENM) and electrochemical impedance spectroscopy (EIS). The results show that the Zn-Ni coating alloys exhibit nobler potentials and low current density indicating the increase of the corrosion resistance of the sample due to the protective effect provided by the oxides formed on Zn-Ni coating alloys. However, the corrosion products allow the mass transfer of aggressive species showing a semi-infinite behaviour. The protective effect shows a relationship with the Ni amount employed. The hot-dip method for deposition of ZnNi coatings using 0.5% Ni exhibit the best performance. [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]

This paper presents a techno-economic analysis to construct an experimental Parabolic Trough Solar collector, using alternative materials and for academic purposes. Concentrated solar power has considerable potential for growth in Brazil, considering the levels of direct solar irradiation, land availability and low current state of use of this technology. It has also a good potential to replace fossil fuels in many thermal applications, helping to decarbonize Brazilian Energy Matrix. The prototype was manually built in a garage. It was made of the following materials: plywood, with steel tube reinforcements for the structure; copper, covered with black ink, for the collector tube; galvanized steel sheets covered with thin aluminum sheets for the reflector. A hydraulic system was developed to run the tests, and an electronic system, using an Arduino-UNO, a laptop and temperature and flow meter sensors to collect data. This prototype does not have neither a solar tracking system nor a glass cover. It has an opening area of 2.34 m2 and had a material cost of around $129.00. Under an estimated direct solar irradiation of 900 W/m2, the prototype was able to absorb heat at a rate of 1.2 kW (52.38% of efficiency). It was also created a simplified method for building similar devices. For the purpose this prototype was built, the materials of the collector tube and the reflector were considered approved. The plywood in the structure had a low reliability and high cost. The results found have limitations for industrial applications, but can offer strategical information for building this type of device in universities and research centers. [ABSTRACT FROM AUTHOR]

This article presents an optimization design of the ... &EWMA chart for monitoring a cold rolling process producing galvanized steel coils. Using real data from industry, the results show that the detection effectiveness of the ... &EWMA charts is better than the optimal ... chart and the optimal EWMA chart in terms of Expected Average Number of Observation required to identify an out-of-control case (EANOS) by about 36% and 10%, respectively. The optimization design of the ... &EWMA charts ensures that extra inspection resources will not be necessary, and the false alarm rate of the charts will not be increased. [ABSTRACT FROM AUTHOR]

This article presents an optimization design of the X &EWMA chart for monitoring a cold rolling process producing galvanized steel coils. Using real data from industry, the results show that the detection effectiveness of the X &EWMA charts is better than the optimal X chart and the optimal EWMA chart in terms of Expected Average Number of Observation required to identify an out-of-control case (EANOS) by about 36% and 10%, respectively. The optimization design of the X &EWMA charts ensures that extra inspection resources will not be necessary, and the false alarm rate of the charts will not be increased. [ABSTRACT FROM AUTHOR]

This article presents an optimization design of the X &EWMA chart for monitoring a cold rolling process producing galvanized steel coils. Using real data from industry, the results show that the detection effectiveness of the X &EWMA charts is better than the optimal X chart and the optimal EWMA chart in terms of Expected Average Number of Observation required to identify an out-of-control case (EANOS) by about 36% and 10%, respectively. The optimization design of the X &EWMA charts ensures that extra inspection resources will not be necessary, and the false alarm rate of the charts will not be increased. [ABSTRACT FROM AUTHOR]

The down conductor system is one of the essential components besides the air termination system and the earth termination system, since that the objective of this study is to investigate the effect of different type of down conductor materials on the varying angles of down conductors with different separation distances due to lightning strike. There were numerous materials of down conductor utilized worldwide in the Lightning Protection System (LPS) installation. In this circumstance, the aluminium and galvanized steel materials are taken into consideration to be resolved with reference to the electric field profile. The accomplished whole system of Lightning Protection System (LPS) for sheltered structure, is being modelled that abide by the standard of MS IEC 2007. Further, this entire system is modelled based on the outstanding of soil resistivity grounding parameter. Consequently, it is found that the galvanized steel material is more critical than aluminium in most angles due to the higher electric field intensity. [ABSTRACT FROM AUTHOR]

Fouling problems are of major concern to many industries using water and heat, especially in cooling processes. Once scale forms on a heat transfer surface, at least two major problems associated with the scale occur. The first problem is the deterioration of the heat transfer equipment performance due to the much lower thermal conductivity of scale compared to that of pipe materials. The second major problem is that a small change in the tube diameter substantially increases the pressure drop across the water piping system. The fouling for cooling towers in CSP plants is an influential factor on whether the equipment is performed or not. Beside the water cooling quality, the tube material surfaces are being allowed increasing attention to evaluating the fouling phenomena. Those parameters can in fact highly affect the performance of a cooling tower; hence, it is central to evaluate how the used heat exchanger tube materials will be impacted by fouling factors. Although fouling can have an impact on a cooling tower performance through various ways, including water flow, air/water temperatures, water quality, and tubes materials. In this paper, we are focusing our attention to the fouling scale and its effect on the overall heat transfer coefficient, heat transfer and fouling resistance of deposits fouling through a comparative study based on SEM images, X-ray diffraction analysis and experimental results of polymers and galvanized heat surface materials. In order to understand the fouling behavior, an apparatus scale unit of a hybrid cooling tower designed for CSP plants was installed in the Green Energy Park (GEP) research platform, located in Benguerir, Morocco, in the framework of the MinwaterCSP project (supported by EU H2020). In this scope, the fouling deposits on the polymer and galvanized steel tubes were investigated. [ABSTRACT FROM AUTHOR]

A cold roll bonding (CRB) process for the symmetrical bonding of two sheets of the steel DX-51 (1.0226) with a galvanized zinc coating is presented. The coating was applied to form an intermediate layer between the two steel substrates during the bonding. The study is divided in two sections describing the role of the heat treatment prior to the CRB process (heat pre-treatment) as well as after the CRB process (heat post-treatment). The filming theory supposes that for establishing a firm bond, the superficial layers should feature an increased hardness in comparison to the substrate to overcome the oxide film on the surface. Since zinc is more ductile than iron, a bonding of galvanized steel sheets according to this mechanism is rather unlikely. By applying a heat pre-treatment prior to the roll bonding, the formation of brittle intermetallic Fe and Zn phases can be facilitated. These brittle phases fracture during rolling, and thus, allow for a contact of the juvenile formed steel layers. Within this study, steel sheets were heat pre-treated in an oxygen-free atmosphere in the temperature range from 450 °C to 550 °C. Additionally, the influence of the coating’s thickness was investigated. A heat post-treatment was performed to strengthen the bond by increased diffusion activity. The influence of the zinc diffusivity was analyzed by heat treatment of the bonded samples in the relevant temperature range for zinc diffusion at 180 °C. The bonds were analyzed by scanning electron microscopy and tensile shear tests. [ABSTRACT FROM AUTHOR]

The performance of carbon steel, galvanized steel and aluminium after one month exposed in the atmospheric coastal area, which is in Limbangan and Karangsong Beach, West Java, Indonesia was evaluated. The corrosion rate was determined by weight loss method and the morphology of the steel after exposed was observed by Scanning Electron Microscopy(SEM)/Energy Dispersive X-Ray Analysis(EDX). The site was monitored to determine the chloride content in the marine atmosphere. Then, the corrosion products formed at carbon steel were characterized by X-Ray diffraction (XRD). The result showed the aggressively corrosion in Karangsong beach, indicated from the corrosion rate of carbon steel, galvanized steel and aluminium were 38.514 mpy; 4.7860 mpy and 0.5181 mpy, respectively. While in Limbangan Beach the corrosion rate of specimen carbon steel, galvanized steel and aluminium were 3.339; 0.219 and 0.166 mpy, respectively. The chloride content was found to be the main factor that influences in the atmospheric corrosion process in this area. Chloride content accumulated in Karangsong and Limbangan was 497 mg/m2.day and 117 mg/m2.day, respectively. The XRD Analysis on each carbon steel led to the characterization of a complex mixture of iron oxides phases. [ABSTRACT FROM AUTHOR]

The waste pickle liquor coining from the pickle line in galvanization process of steel is collected in the waste acid storage tanks. The size of the storage capacity determines, for how long the pickling line and the acid regeneration plant can be operated independently from one another. The combustion gases which build up a certain flow pattern inside of the reactor dry up the droplets of the pre-concentrated acid coming down from the spray nozzles and in the hot part of the reactor the l eCb is decomposed according to the following formula: 2 FeCl2 + 2 H20 + 1/2 02 → Fe203 + 4 HCl The solid particles (Fe203) will fall down to the lower cone of the reactor in the form of powder and are discharged through a rotary valve which keeps gases inside of the reactor separated from the outside atmosphere. In order to reuse Iron Oxide obtained during the process of cleaning hydrochloric acid, our team focuses on the conditions of valorization of the oxide F?2?3,. We tried the doping of this product with metal ions such as: Mn2+, Al3+, Zn2+. We succeed to isolate, by dry way, a series of compounds with interesting shades of colors. The heat treatment of these pigments in the molten medium at lower temperature (900.°C) has improved their morphology. The powders obtained were characterized by X-ray diffraction (XRD), scanning electron microscopy and EDX. The pigments obtained have sufficient thermal stability to be used in various applications. [ABSTRACT FROM AUTHOR]

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]

Recently zinc based coatings on cold rolled steel with improved functionality in terms of forming and/or corrosion behaviour have been intensively investigated in the steel industry1,2,3. One of the most promising products are zinc magnesium alloys produced in hot dip galvanizing process. These coatings were already introduced in construction industry a few years ago1. With some modifications the improved properties of the coating are also interesting for automotive industry. In the present work the tribological potential of hot dip galvanized zinc magnesium coatings (HDG/ZM) produced at an industrial line under regular production, was studied in terms of sliding properties, adhesive and abrasive tool wear. First a short introduction into surface morphology of HDG/ZM will be given. For the tribological characterization of the material, which is the main topic of the contribution, different tests were performed on hot dip galvanised zinc magnesium material and results were compared with classic hot dip galvanized zinc coating (HDG/Z). The investigations are mainly based on the strip draw test which allows the determination of the friction coefficient directly by using a constant contact pressure. Deep drawing property was tested by forming model cups. The abrasive tool wear was tested using a standard test for material used in automotive industry. The adhesive tool wear was investigated by characterizing the coating material transferred to the tool in the strip draw test. All performed tests show an improved drawability of HDG/ZM compared to classical HDG/Z reference material. However the most promising difference between HDG/ZM and HDG/Z is that galling was found to be less for HDG/ZM than for HDG/Z. Therefore HDG/ZM is an interesting system not only with respect to corrosion protection but also in terms of tribology and provides clear advantages in formability. [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]

Measurements performed on friction-stir butt welds in aluminum and resistance spot welds in galvanized steel are used to illustrate how ultrasonic phased arrays can be used to provide high-resolution images of welds. Examples are presented that demonstrate how information extracted from the ultrasonic signals can be used to provide reliable feedback to welding processes. Modeling results are used to demonstrate how weld inspections can be optimized using beam-forming strategies that help overcome the influence of surface conditions and part distortion. [ABSTRACT FROM AUTHOR]

Metallurgical examination of galvanized steel resistance spot welds was used to gauge the capabilities of two ultrasonic, non-destructive, scanning techniques. One method utilized the amplitude of the echo from the weld faying surface, while the other used the spectral content of the echo train to map the fused area. The specimens were subsequently sectioned and etched, to distinguish the fused, zinc-brazed, and non-fused areas. The spectral maps better matched the metallurgical maps, while the interface-amplitude method consistently overestimated the weld size. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]