Electric Arc Welding Research Articles

Study of the effect of SMAW welding speed on the microstructure and crystal stability of X70 steel using X-ray diffraction

This study investigates the impact of manual electric arc welding (SMAW) speed on the microstructure of X70 steel. Welding was performed at two distinct speeds: S1 = 20 mm/min and S2 = 35 mm/min, at the COSIDER BISKRA workshop in Algeria. X-ray diffraction (XRD) analysis was conducted on the welded zones to examine crystal orientation, size, dislocation density, and structural stability across different welding areas, including the base metal (MB), heat-affected zones (HAZ1 and HAZ2), and weld zones (WZ1 and WZ2). The XRD results revealed that key crystal peaks, such as {110} and {200}, retained their positions at both welding speeds, though variations in {110} peak intensity were noted. The lower welding speed (S1) resulted in a higher heat input, which enhanced crystal stability, increased crystal size, and reduced dislocation density. On the other hand, the higher speed (S2) produced lower heat input, leading to smaller crystal sizes, increased residual stresses, and a greater number of defects due to rapid cooling. These findings underscore the critical influence of welding speed on heat input, cooling rates, and their consequent effects on microstructure. The study highlights the importance of optimizing welding parameters to balance microstructural integrity, mechanical performance, and production efficiency.

Microstructure and Mechanical Properties of Layered Billets from Various Grades of Austenitic Steels Grown by Additive Electric Arc Welding

Microstructure and Mechanical Properties of Layered Billets from Various Grades of Austenitic Steels Grown by Additive Electric Arc Welding

ANALYSIS OF THE QUALITY OF THE RESTORED GEAR TOOTH OF LARGE-MODULE GEARS

This study examines the quality of a gear tooth surface fragment restored through electric arc welding. Visual inspection revealed a defect-free, dense surface. Macrostructure examination displayed uniformity and absence of cracks in the metal sample. The high hardness (HRC-36.61) of the weld deposit is crucial for wear resistance, while the base metal, with lower hardness (HRC-29.09), ensures ductility and impact toughness. Martensitic and residual austenitic structures in the weld deposit indicate deformation-resistant properties, with austenite providing good ductility and martensite contributing to high hardness and strength, making the material resistant to wear and deformation under dynamic loads. Thin lens-like martensitic plates and a reed-like structure suggest unique formation characteristics during electroslag welding’s oxidizing-reducing reactions. Microstructure analysis revealed a finer structure in the weld deposit compared to the base metal. The base metal exhibited a ferrite-pearlite structure typical of many steels, unchanged after welding. The weld deposit showed elevated carbon (0.70 %) and manganese (1.38 %) concentrations, typical for weld deposits, influencing mechanical properties. Elements like manganese and molybdenum enhance wear resistance, while the presence of chromium (0.42 %) and nickel (0.12 %) improves corrosion resistance, crucial in aggressive environments. Keywords: large-module gears, tooth wear, electro slag surfacing, hardness, analysis

Prediction of Failure Due to Fatigue of Wire Arc Additive Manufacturing-Manufactured Product

Currently, the focus of production is shifting towards the use of innovative manufacturing techniques and away from traditional methods. Additive manufacturing technologies hold great promise for creating industrial products. The industry aims to enhance the reliability of individual components and structural elements, as well as the ability to accurately anticipate component failure, particularly due to fatigue. This paper explores the possibility of predicting component failure in parts produced using the WAAM (wire arc additive manufacturing) method by employing fractal dimension analysis. Additionally, the impact of manufacturing imperfections and various heat treatment processes on the fatigue resistance of 30CrMnSi steel has been investigated. Fatigue testing of samples and actual components fabricated via the WAAM process was conducted in this study. The destruction of the examined specimens and products was predicted by evaluating the fractal dimensions of micrographs acquired at different stages of fatigue testing. It has been established that technological defects are more dangerous in terms of fatigue failure than microstructural ones. The correctly selected mode of heat treatment for metal after electric arc welding allows for a more homogeneous microstructure with a near-complete absence of microstructural defects. A comparison of the fractal dimension method with other damage assessment methods shows that it has high accuracy in predicting part failure and is less labor-intensive than other methods.

Structure and properties of 08KhMFA and 30KhGSA steels obtained by electric arc welding

Structure and properties of 08KhMFA and 30KhGSA steels obtained by electric arc welding

Influence of Submerged Arc Welding Current Intensity on the Mechanical Properties and Microstructure of Pressure Vessel P355N Steel.

This article presents a study on the influence of the intensity of the welding current on the properties of the mechanical strain strength of welded joints made by using submerged arc welding technology. The influence of the welding current on the microstructure of the welded joints was also observed in different regions of the cross-section of the welding seam. Also subject to observation was the mode of influence of the welding current on the geometry and dimensions of the welding seams. The welded samples were obtained using five different welding regimes whose main variable was the intensity of the welding current, which had values between 300 A and 700 A. The criterion used as a reference for comparing the effects produced by the studied welding regimes was a standard welding regime that is used in the industry for welding railway tank wagons, with a welding current intensity of 480 A. The base material used in the experiments was a fine-grained carbon steel specially intended for the manufacture of pressure vessels identified as P355 N; the semi-finished product from which the samples were made consisted of 6 mm thick laminated sheets used in the manufacture of the covers of the vessels that make up the railway tank wagon. The aim of this study was to highlight the differences that may appear through varying the current welding parameter and identify welding regimes that can provide welded joints with superior mechanical properties compared to what is currently employed in the industry. This study focused on the most widespread technology of welding pressure vessels: the submerged electric arc welding method.

The Experimental Design of a Spring Coil Compressor Remover for Automobile

This study examined various types of coil spring compressors in the automobile industry. A coil spring compressor for compressing a coil spring during the assembly of subassemblies of automotive suspension systems, having a head jaw positioned above a base and movable concerning the base. The coil spring compressor is provided with a pair of guide bars suspended from the head plate and on which a slidable carriage is mounted. The carriage carries a pair of compressing assemblies facing each other in vertical positions and positioned at both the upper and lower parts of the coil spring. Each assembly comprises a pair of compressor arms interconnected with each other. Each compressor arm is provided with a jaw mount to which a compressing hook is adjustably attached. The jaws are introduced between a few successive turns of the coil spring by operating handles provided on the compressor arms. The purpose of this design is to be used on various types of suspension disassembly and assembly of vehicles, the tool includes the upper and the lower jaw which by the smooth turning of the screw lowers to compress the coil spring or turns to release the compressed coil spring. The new design was made from mild steel and the tools used for the construction were an electric arc welding machine, power, and hand hacksaws, the bench vice, assorted hammers, vice, etc. The findings indicated that the new design is more efficient than the existing one. It was also recommended that car owners who visit the workshop should insist on the use of the right compression tool in the disassembly and assembly of their suspension systems.

Enhancing Weld Quality: A Review of Optimization Techniques for Electric Arc Welding Parameters in Mild Steel Grade Fe 500 Using Taguchi Method

Abstract: Electric arc welding stands as a cornerstone in various industries for its efficacy in joining metal components. The paramount importance of achieving impeccable welds cannot be overstated, as they are pivotal for maintaining structural integrity and performance. This review meticulously scrutinizes optimization techniques tailored for electric arc welding parameters, with a specific focus on mild steel grade Fe 500, leveraging the Taguchi method. Renowned for its efficiency in experimental design and optimization, the Taguchi method has been extensively harnessed to refine weld quality by mitigating defects such as porosity, cracks, and lack of fusion. Offering a comprehensive insight, this paper first delineates the pivotal parameters inherent to electric arc welding and elucidates their profound impact on weld quality.

Optimization of Welding Parameters for Minimizing Defects and Porosity in Electric Arc Welding of Mild Steel Grade Fe 500 Using of Taguchi Method

Abstract: Electric arc welding is a widely used technique in industrial applications for joining metals, including mild steel grade Fe 500. However, the process is susceptible to defects such as porosity, which can compromise the integrity and quality of welds. In this study, we investigate the optimization of welding parameters to minimize defects and porosity in electric arc welding of mild steel grade Fe 500, utilizing the Taguchi method. The Taguchi method, known for its efficiency in optimization studies, is employed to systematically identify the most influential welding parameters and their optimal levels. Through a series of experiments based on the Taguchi orthogonal array design, we vary parameters such as current amperage, voltage, and electrode size to explore their effects on weld quality. The experimental results reveal significant insights into the relationship between welding parameters and defect formation. By analyzing signal-to-noise ratios and ultimate tensile strength, we quantify the effects of parameter variations on weld quality. The Taguchi analysis enables us to identify the optimal combination of welding parameters that minimizes defects and porosity while maximizing weld strength.

Study of the corrosion resistance of high chromium white cast iron welds in the presence of NaOH (30% w/w)

– In the mining industry, specifically in bauxite processing, adverse working conditions demand high mechanical and chemical resistance. For such conditions, the choice of potentially resistant materials, such as high chromium white cast iron (HCr-CWI), is necessary. However, presently, there is no effective recovery of equipment made with HCr-CWI, primarily due to the machining difficulties encountered during the repair process. An alternative recovery method is being developed by the Laboratory of Metallic Materials Characterization at UFPA – LCAM, using electric arc welding with two filler metals: the ER307L stainless steel wire andsa high Mn value wire. Within this context, this study aims to investigate the corrosion resistance of the welded joint obtained with these two filler metals. The base metal (HCr-CWI) was analysed as a reference, alongside the metals generated by the welded joints, ER307L and high Mn. The samples underwent tests involving optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and electrochemical tests for corrosion potential, polarization, and impedance. It was observed that the samples exhibited a similar matrix-carbide structure but with different organization and volumes. However, the electrochemical behaviour in terms of corrosion potential, polarization, and impedance was similar, with very close resultant values: 50 V; 3.53 μA; 0.18 kOhms, respectively. This was supported by the corrosion rate of 0.4mmpy and explained by calculations of Cr and Ni volume, which showed inverse concentration magnitudes among the samples.

Physical and Mechanical Properties of Butt Welded Joints of Aluminum Alloys

Along with the improvement of joining technologies with argon arc, plasma and laser welding for aluminum alloy elements, high efficiency of joints made with the use of friction stir welding (FSW), which has low energy consumption and is almost equally strong as base metal, has been achieved. However, the processes of friction stir welding have not been sufficiently studied and can lead to softening of aluminum alloy welds up to 0.65 of base metal strength. When studying the effect of friction stir welding and mechanized electric arc welding in argon medium, welded joints of aluminum alloys of Al-Si-Mg (AD35T1, 6082-T6) and Al-Zn-Mg alloying systems (1915T) were subjected to tensile and impact tests. The values of strength, elastic and plastic characteristics of argon arc welded specimens of 1915T, AD35T1 and 6082-T6 alloys were obtained. For alloy 6082-T6, the same characteristics are presented for FSW welded specimens. Decrease in strength and ductility in the zones of welded joints for both welding methods is observed. At the same time, the highest relative values of strength and offset yield strength of the welded joint are fixed for friction stir welding. Slight decrease in modulus of elasticity obtained for argon-arc welded specimens was recorded. The impact strength is constant for each welded joint zones in the temperature range of +20 – -60оC and increased in weld metal of FSW butt joints of alloy 6082-T6.

Gas Tungsten Arc Welding (GTAW) and Underwater Welding (UW) on Brass Propeller Repair

Over time, marine building technology has experienced very significant developments and there are several variations of improvements that can be made to suit needs and conditions. A ship's propeller is a ship component that often experiences collisions with hard objects floating in the water which can cause the blades of the propeller to experience damage such as bending, cracking or breaking. In this case, the propeller should be repaired immediately so as not to disrupt the smooth operation of the ship. Repairing broken propeller blades can be done using a welding process. Welding is a technique of joining metals by melting part of the parent metal and filler metal with or without additional metal and producing continuous metal. Underwater Welding is a welding process that occurs in wet conditions, meaning that the electrode and object are in direct contact with air, while Gas Tungsten Arc Welding (GTAW) is an electric arc welding process that uses an untreated electrode that does not melt. This research was conducted to analyze the welding measurement results of Gas Tungsten Arc Welding (GTAW) and Underwater Welding on brass materials. To support the analysis process, testing activities are carried out including tensile tests (tensile test), hardness tests (hardness test) and macrographic observations on the results of welding materials.

Cavitation Erosion of the Austenitic Manganese Layers Deposited by Pulsed Current Electric Arc Welding on Duplex Stainless Steel Substrates

Fe-Mn-Cr-Ni alloys like Citomangan, delivered in the form of powders, tubular wires, and coated electrodes, are intended for welding deposition operations to create wear-resistant layers. Their main characteristic is their high capacity for surface mechanical work-hardening under high shock loads, along with high toughness and wear resistance. In order to increase the resistance to cavitation erosion, hardfacing of Duplex stainless steel X2CrNiMoN22-5-3 with Citomangan alloy was performed using a new welding technique, namely one that uses a universal TIG source adapted for manual welding with a coated electrode in pulsed current. Cavitation tests were conducted in accordance with the requirements of ASTM G32—2016 standard. Comparing the characteristic cavitation erosion parameters of the manganese austenitic layer, deposited by this new welding technique, with those of the reference steel, highlights an 8–11 times increase in its resistance to cavitation erosion. Metallographic investigations by optical microscopy and scanning electron microscopy (SEM), as well as hardness measurements, were carried out to understand the cavitation phenomena.

Taguchi Parametric Optimization of Mild Steel Weld-Strength in Arc Welding Process

Abstract—In the welding process, the major factors whose selection contributes to the welded product as they all affect the strength and quality of the weld strength to a larger extent are hardness, electrode diameter and weld design (edge preparation). The purpose of this thesis is to efficiently determine the optimum welding operation parameters for achieving the highest breaking strength in the range of parameters. In order to meet the purpose in terms of both efficiency and effectiveness, this study will utilize the Taguchi parameter design methodology. The study includes selection of parameters, utilizing an orthogonal array, conducting experimental runs, data analysis, determining the optimum combination, verification experimentally finally the Modelling of input parameters (Hardness, Diameter of Electrode & Weld Design) and output parameter (Breaking Strength) is done using Taguchi optimization technique. Key words: Welding Parameters, Electric Arc Welding, Taguchi Method, welding design, hardness.

Tensile Strength of S45C Steel Material for SMAW Welding with Various Cooling Media

One of the welding methods that is widely used is the SMAW welding process (Shield Metal Arc Welding) which is also called Electric Arc Welding. This research aims to analyze the effect of variations in cooling media on tensile test results on welding results of S45C steel material. This research uses S45C material. The material is subjected to single vee joint welding, where at the completion of welding the material is immersed in a cooling medium of oil, water, air and is not treated in this research. From the research results, it can be concluded that the highest ultimate tensile strength (Tu) value is when the material is cooled with oil media, where the highest value is 517.15 N/mm2, followed by air cooling media, where the highest value is amounted to 475.85 N/mm2, and the lowest was with water cooling media where the highest value was 455.50 N/mm2. Thus, cooling with oil as a medium is the best between the two cooling media, water and air.

Effects of Welding Techniques on the Corrosion Resistance of Mild Steel

The performance and longevity of welded structures depend heavily on corrosion resistance, particularly when mild steel is used as the primary material. The paper provides an overview of the investigation of the influence of various welding techniques on the corrosion resistance of mild steel. The study combines mild steel specimens using spot-welding, gas metal arc, and electric arc welding techniques. Electrochemical and immersion testing techniques are used to assess the welded samples' resistance to corrosion. The impact of metal microstructure, welded zone surface characteristics, corrosion rates, and filler material selection on corrosion resistance is examined. The results demonstrate that the choice of welding process has a significant effect on mild steel corrosion resistance. Some techniques have a higher level of corrosion resistance owing to the use of heat. As exposure duration rises, both diluted and concentrated hydrochloric acids cause weight loss in the absence of an inhibitor. The temperature increased over time until 190 minutes, which resulted in a decrease in temperature efficiency. In the impact test, adding 3%, 6%, and 9% of the welded components to the metal alloy increased the impact's energy output from 12.32 J to 12.69 J, 12.99 J, and 13.51 J, respectively. The energy effect of the reinforced mild steel was reduced owing to the brittleness of the welded parts relative to the ductile metal matrix. The composite absorbs impact stresses, and the enhanced weight ratio of the welded mild steel thereby increases its toughness.

Usporedba topitelja za ATIG zavarivanje i njihov uticaj na mehaničke osobine

The application of conventional electric arc welding in argon protection (TIG welding process) has limited possibilities. These limitations are primarily related to the thickness of the welded material and the need to prepare the groove for their welding. Overcoming these limitations in TIG welding was done by using activating flux, so the procedure was named ATIG (A-TIG) welding. The paper presents the results of research into the application of activating fluxes in welding austenitic stainless steel 316L with a thickness of 6 mm. By using the BC-31 and QuickTIG melters of different chemical bases, we compare the mechanical properties of the welded joints, as well as with the welded joints of the same material obtained using the conventional TIG procedure. The results show that the best mechanical properties are possessed by welded joints realized by the ATIG process using a mixture of activating fluxes BC - 31 (50%) and QuickTIG (50%) (green + white flux).

Effect of the Molybdenum Content on Wear and Corrosion Behavior of Fe-B-Based Surface-Alloyed Layer

In this study, Fe-Mo-B-based hardfacing electrodes containing different amounts of Mo were coated on an AISI 1020 steel substrate using the electric arc welding method. The findings show that molybdenum is highly effective on the microstructure and minor changes in the coating composition affect the phases and morphological properties. In the hardness tests, an increase of 73% was achieved in the Fe14Mo2B4-based hardfacing coating, compared to the base material, and a 30% increase was achieved, compared to the Fe16B4-based coating. The highest hardness value was measured as 56.4 HRC and the highest phase hardness was measured as 3228 HV in the FeMo2B4 phase. The lowest wear rate was measured in the Fe14Mo2B4-based coating. The wear rate of the Fe14Mo2B4-based coating was 8.1 times lower than that of the substrate material and 4.7 times lower than that of the Fe16B4-based coating. According to corrosion test results, the highest corrosion resistance was obtained in the Fe16B4-based coating. The current density value of the Fe16B4-based coating was measured to be 13.6 times lower than that of the substrate material.

Comparative study of hardfacing applications on structural steel surfaces to improve ballistic properties

The aim of this study was to develop plates resistant to ballistic limits by welding on S355JR steel plate with Fe-Cr-C and austenitic electrodes. A total of four different weld coated materials were prepared for ballistic testing. For these four different coatings, E Z Fe 14 (Fe 14), E Fe 16 (Fe16) hardfacing electrodes and E 18 8 Mn R 3 2 (307) austenitic stainless steel electrode were selected, respectively. The coatings were made in the electric arc welding machine, with two different coatings on the surface for each material. These are Fe 14 – Fe 14, Fe 16 – Fe 16, 307-Fe 14 and 307-Fe 16, as the first layer and the second layer, respectively. In all coatings, the welding current was kept constant at 150 A and the welding voltage was kept constant at 27 V. The microstructure, hardness, and ballistic properties of the hardfacing surfaces were investigated using scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) to analyze the phases and components. The hardnesses of the hardfacing surfaces were determined by Vickers methods from the weld metal to the base metal. Ballistic tests were conducted according to NIJ Level III standards, firing 7.62 × 51 mm AP bullets from a distance of 10 m to calculate the effects of the bullets on the plates, the kinetic energy of the bullet, and the amount of energy absorbed by the plates. Welding for hard surface coating achieved with the combination of 307 - Fe 14 electrodes provides the highest ballistic limit velocity at 830 m/s, while the lowest limit is observed in the material welded with Fe16-Fe16 electrodes at 747 m/s. Fe-Cr-C electrodes were found to be effective as main or auxiliary components when designing armor plates. This study highlights the potential of hardfacing techniques to improve the ballistic properties of steel surfaces, with implications for the development of protective materials across various industries.

РОЗРОБКА ТА ДОСЛІДЖЕННЯ МОДЕЛІ ПІД-РЕГУЛЯТОРА НАПРУГИ ДУГИ ПІД ЧАС НАПЛАВЛЕННЯ

The development and testing of a PID-controller model capable of automatically adjusting and maintaining the specified arc voltage during electric arc welding are presented. Some features of arc surfacing processes are analyzed. In particular, the choice of surfacing modes, as well as the main devices - potentiometers, which are used in the electrical circuits of surfacing installations to regulate the main parameters of surfacing modes - voltage and current. Evidence is presented for the need to control the voltage directly on the arc, rather than the voltage on the power source, to regulate the welding process. Based on this analysis, a model of the PID- controller of the arc voltage during arc welding was created using the Simulink MATLAB program. The test results of the PID-controller show that the device provides more accurate and stable setting of the deposition mode than traditional control methods. The PID-controller will make it possible to significantly reduce possible errors in the development and use of technologies of automatic arc welding of various parts and products. References 10, figures 6, table 1.