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One of the main problems experienced when using laser cutting equipment is the wrong selection of cutting parameters. This incorrect selection decreases the cut surface quality, which is hardly re‐established, injuring the overall process quality. Thus, this study aims to improve and optimize the laser cutting process using fiber and CO2 laser equipment. In this work, the potentialities of both laser equipment were studied, changing the main cutting parameters: laser power (W), cutting speed (mm/min) and gas pressure (bar). Operators usually follow the manufacturer's recommended values for these parameters, and often, the parts present low cut surface quality because of the high level of burr and roughness on the cut's edge, which negatively impacts the productivity of the laser cutting process. Thus, using different parameters recommended by machine manufacturers on AISI 316L stainless steel and St12 cold rolled steel, this study aims to provide insightful information that can be used to optimize the steel laser cutting process. In addition, the tests were carried out with the machine operators, which made it possible to understand the day‐to‐day problems associated with production quality and establish a working method to optimize the process. Pulsed CO2 laser causes uneven burr, while fiber laser is uniform. Compare fiber and CO2 laser techniques for cutting AISI 316L.

The inhibitive properties of the extracts of Cascabela thevetia and Jatropha curcas were comparatively studied on corrosion of mild steel in H2SO4 acid. The extracts of both plants contained active phytochemical constituents such as tannins, saponins, alkaloids, flavonoids, terpenes and phenols which made them useful as good corrosion inhibitors. The extract concentrations were varied from 0.3 to 1.5 g/L during both the gravimetric and gasometric analyses for an exposure time of 7-28 days. The weight loss of the coupon, corrosion rate, surface coverage and inhibitive efficiency was evaluated for both the extracts. The results of the gravimetric and gasometric analyses indicated that inhibitive efficiency increased with an increase in the concentration of inhibitors and the highest was 55.77% for Jatrophas curcas at the concentration of 1.5 g/L. The weight loss was a little lower for Cascabela thevetia (4.36 g) compared to Jatrophas curcas (4.66 g) at the highest exposure time used (28 days). Cascabela thevetia has a better surface coverage (0.68) than Jatropha curcas (0.61), hence, Cascabela thevetia inhibits better for a 7-day exposure time. However, when the mild steel was further exposed for more than 7 days, Jatropha curcas exhibited a better inhibitive property. The highest and least hydrogen gas evolution was obtained at 0.3 g/L concentration (7 minutes) and 1.5 g/L concentration (1 minute) for both Cascabela thevetia and Jatropha curcas leaves extracts, respectively. Based on the results, the utilization of extracts of Cascabela thevetia and Jatropha curcas leaves as replacements for toxic organic inhibitors in industries are recommended.

This study analyzed an atmospheric corrosion sensor using strain measurements (ACSSM) with an active dummy method for corrosion product experiments. An initial compensation thermal strain experiment was performed with elapsed time. Further analyses used dry-wet environments with salt water spray to investigate the thickness reduction performance of the corrosion product on low-carbon steel samples. The ACSSM with an active dummy method accurately measured signals induced by the specimen thickness reduction, despite the noise in the signal. Moreover, the effects of corrosion products on the signal were discussed.

This experiment promotes economically, eco-friendly benefitted inhibitor and also avoids pollution and recycles the drugs. In this experiment expired Gentamicin drug was tested its inhibitive effect in 1 M HCl acid medium on mild steel, with the electrochemical and weight loss techniques. The Various parameters were calculated such as inhibition efficiency, corrosion rate and surface coverage. The inhibition efficiency shows increases when inhibitor concentration, immersion period and temperature increase in weight loss method. Obtained results in electrochemical Impedance and weight loss studies are very much excellent agreement with each other. Thermodynamic parameter free energy value was negative, it shows spontaneous adsorption of inhibitor on the surface of the mild steel. The adsorption nature on the surface of mild steel was under conformity by Langmuir adsorption isotherm. The surface morphology, with and without inhibitor was studied with using scanning electron microscopy.

A new material that can be used to replace single steel in high-strength tanks is mild steel cladding Super Duplex Stainless Steel (SDSS). The method of producing multilayer Super Duplex Stainless Steel (SDSS) is the cladding of mild steel Many processes are carried out such as welding Plasma Direct Energy Deposition (DED), laser, and electro-slag strip. In the manufacturing industry, hot rolling is a simple process. Because the procedure is quick and uses inexpensive, traditional equipment, it is referred to as a simple method. The use of seawater was chosen because salty conditions favour corrosion. In this work, the effects of temperatures of 900?C, 1000?C, and 1050?C on the microstructure and corrosion resistance of hot rolled materials are investigated. The investigation of corrosion resistance by examining the microstructure and material properties using metallography, X-ray diffraction, Electrochemical Impedance Spectroscopy (EIS), and Scanning Electron Microscope (SEM) is the main goal of this work. The results of the study demonstrated that when the hot rolling temperature was increased, carburization and decarburization occurred and the corrosion resistance decreased.

Wire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas metal arc welded (GMAW) based WAAM process provides a higher deposition rate than other methods, making it suitable for additive manufacturing. The fabrication of mild steel (G3Si1), austenitic stainless steel (SS304), and a bimetallic sample of both materials were completed successfully using the GMAW based WAAM process. The microstructure characterization of the developed sample was conducted using optical and scanning electron microscopes. The interface reveals two discrete zones of mild steel and SS304 deposits without any weld defects. The hardness profile indicates a drastic increase in hardness near the interface, which is attributed to chromium migration from the SS304. The toughness of the sample was tested based on the Charpy Impact (ASTM D6110) test. The test reveals isotropy in both directions. The tensile strength of samples deposited by the WAAM technique measured slightly higher than the standard values of weld filament. The deep hole drilling (DHD) method was used to measure the residual stresses, and it was determined that the stresses are compressive in the mild steel portion and tensile in austenitic stainless steel portion, and that they vary throughout the thickness due to variation in the cooling rate at the inner and outer surfaces.

The paper is concerned with the development of a data acquisition system for the measurement of temperature used for metal cutting. In this study, machining tests were performed and an analysis of the temperature and wear of the cutting tool is presented herein. In metal cutting operations, the wear of tools is generated largely due to the heat emitted from the cutting zone. Therefore, a coolant is often used to cool down the cutting area and protect the cutting tools. However, because of environmental concerns, engineers now try to avoid using cutting coolants and perform cutting operations in almost dry conditions. In this study, a mild-steel round bar was turned at various feed rates, depths of cut and cutting speeds. A data acquisition system was built to record the cutting temperature while turning the bar. From the study, it is evident that certain combinations of cutting parameters result in higher temperatures than those produced in other experiments. It was established that the depth of cut and cutting speed at their highest values (1 mm and 250 m/min, respectively) contribute largely to the high surface temperature, while the effect of feed rate is intangible. Increasing the cutting speed results in an increase in the cutting temperature. A similar result was observed when the depth of cut was increased. However, increases in feed rate did not significantly cause increases in cutting temperature. In addition, cutting inserts were examined under a scanning electron microscope (SEM) to quantify the tool wear in each experiment. A correlation between tool wear and temperature is clearly noticed. The study concluded that the combination of variations in cutting speed and depth of cut results in severe tool wear action on the tool’s flank face as a result of the intensive heat generated.

Metal additive manufacturing (AM), in particular wire-and-arc additive manufacturing (WAAM), has become over the last few years the breakthrough technology to reduce the environmental impact and increase the efficiency of steel structures. Although intense research effort has been paid toward the mechanical characterization of WAAM-produced thin walls, little attention has been devoted to the investigation of multi-layered thick parts. These latter would indeed expand the application of WAAM for large-scale constructions requiring thicker cross-sections to withstand high loading conditions. The present work provides a comprehensive experimental investigation of mild steel WAAM thick plates from the fabrication to the mechanical and microstructural characterization. First, the fabrication process is presented in full details. From that, microstructural and mechanical characterization is described and discussed, showing a homogeneous microstructure with little influence on the mechanical response along the wall plate thickness, also considering different specimen orientations with respect to the printing directions. The results confirm good mechanical properties of the printed outcomes, in line with those of structural mild steels manufactured with conventional technologies. Little influence on the response along the thickness is reported, thus proving the required quality of WAAM thick parts for applications in the construction sector.

In the present work, the friction surfacing process was applied to manufacture aluminum alloy (AA6351) coatings on low carbon steel (AISI 1020) substrates. After friction surfacing the AA6351 deposited coatings were submitted to two finishing process in order to adjust surface roughness: milling and milling followed by sanding. The corrosion behavior of the two finishing process was compared with the as-deposited condition in order to determine the influence of surface roughness on the corrosion resistance of friction surfacing coatings. The corrosion behavior was examined by electrochemical impedance spectroscopy and potentiodynamic polarization in a 3.5wt.%NaCl solution containing naturally dissolved O2. The results obtained indicated that the elevated surface roughness observed in the as-deposited condition led to relatively lower corrosion resistance in comparison, with lower values for polarization resistance and more anodic corrosion potential.

The University of Technology in Baghdad addresses problems related to the corrosion of metals. In the present investigation, a thiophene derivative, namely, 2-acetylthiophene thiosemicarbazone (2-AT), was synthesized and examined as a corrosion inhibitor for mild steel in a 1-M hydrochloric acid environment by using weight loss and scanning electron microscopic techniques. The inhibition efficiency of this inhibitor increases with increase in concentration, which offered an inhibition efficiency up to 96%. It was found that the inhibition efficiency decreases with long immersion time. The temperature effect on the inhibition performance was studied at various immersion times and revealed that the inhibition efficiency decreases with increasing temperature. The adsorption of the inhibitor on the surface of mild steel in the corrosive environment followed the Langmuir isotherm. The results of scanning electron microscopy (SEM) reveal that the 2-AT molecules confirmed the presence of a protective layer on the surface of a mild steel sample. The density-functional theory as a quantum modeling technique which is used to study the electronic structure reveals that the obtained findings were found to be consistent with the experimental results.