Effect Of Welding Parameters Research Articles

Experimental and Numerical Characterization of Local Properties in Laser-Welded Joints in Thin Plates of High-Strength–Low-Alloy Steel and Their Dependence on the Welding Parameters

Laser welding on thin plates of high-strength steel is increasing in various industrial applications. The mechanical behavior of welded joints depends on their local properties, which in turn depend on the welding parameters applied to join the base material. This work characterizes the local properties of butt-welded joints of thin plates of high-strength–low-alloy (HSLA) steel. This study focuses on the effect of welding parameters on the microstructure, tensile response, microhardness, and weld bead profile. For this purpose, a factorial experimental design was formed, covering a heat input range from 53 to 75 J/mm. This study identified the main effects and interactions of welding speed and laser power on the weld bead profile and on its width. The microstructure, weld bead width, hardness, and tensile mechanical properties were significantly influenced by heat input. Furthermore, numerical simulations on real weld bead profiles revealed high values of the stress concentration factor and suggested a correlation with heat input.

Residual Stress Analysis in Linear Friction Welded Ti17.

Residual stresses with a complex distribution are generated after linear friction welding, which affects the service performance of the weldment. In this work, a numerical model for linear-friction-welded Ti17 (Ti-5Al-2Sn-2Zr-4Mo-4Cr) was developed to investigate the evolution of residual stresses and the effect of welding parameters on residual stresses. Additionally, a method for predicting internal residual stresses was constructed. The results indicate that the residual stresses near the contact interface are largest in the oscillatory direction, peaking at ~661 MPa at 2 mm away from the contact interface. The evolution of stresses is not only related to the inhomogeneous thermal gradient, but also to the forging force. And the stress distribution essentially stabilizes within the duration of the forging force applied. Increasing the amplitude and frequency results in higher peaks of tensile residual stresses and a more concentrated distribution. Conversely, increasing the forging force only reduces the magnitude of the residual stresses. The developed prediction method, based on the similarity of internal residual stress distributions, facilitates the prediction of internal residual stresses using measured surface residual stresses.

Effect of welding parameters on microstructure and mechanical properties of dissimilar AISI 304/ductile cast iron fusion welded joints

Problems associated with dissimilar fusion welding are mainly originated from the differences in melting points, coefficients of thermal conductivity and thermal expansion, …etc., and carbon content when welding dissimilar ferrous materials. In this study, the problems associated with dissimilar fusion welding of stainless steel AISI304 with ductile cast iron DCI grade A536 were investigated. Using shielded metal arc welding (SMAW) process, various welding parameters were studied to investigate the successful/accepted dissimilar welded joint(s). Welding electrodes and welding techniques were the main studied parameters. Microstructural and mechanical investigations were carried out for welded joints under different welding parameters. Tensile, impact and hardness tests coupled with optical and scanning electron microscopic examinations with EDX analysis were made for metallurgical and mechanical evaluations of welded joints. This extensive study could solve the problem of dissimilar welding between ductile cast iron and 304 stainless steel. The main results showed that joints welded by ENiCrFe-3 electrode in root pass and ENiFe-CI in filling passes were the successful dissimilar welded joints with 422 MPa tensile strength which represents 104% of annealed DCI base metal and without any changes in toughness properties, where toughness at HAZ of DCI was 18 J. High Ni content in weld metal increased the strength, ductility and reduced the weld metal dilution.

Application of Pattern Search and Genetic Algorithms to Optimize HDPE Pipe Joint Profiles and Strength in the Butt Fusion Welding Process

The rapid spread of the use of high-density polyethylene (HDPE) pipes is due to the wide variety of methods for connecting them. This study keeps pace with the developments of butt fusion welding of HDPE pipes by exploring the relationship between the performance of the weld joints by studying ultimate tensile strength and exploring the joint welding profiles by studying the shape of the joint at the outer surface of the pipe (height and width of the joint cap) and the shape of the joint at the internal surface (height and width of the joint root). Welding pressure, heater temperature, stocking time, and cooling time were the parameters for the welding process. Regression was analyzed using ANOVA, and an ANN was used to analyze the experimental results and predict the outputs. Two optimization techniques (pattern search and genetic algorithm) were applied to obtain the ideal operating conditions and compare their performance. The results showed that pattern search and genetic algorithms can determine the optimal output results and corresponding welding parameters. In comparison between the two methods, pattern search has a limited relative advantage. The optimal values for the obtained outputs revolved around a tensile strength of 35 MPa (3.45 and 4.5 mm for the cap and root heights, and 8 and 6.98 mm for the cap and root widths, respectively). When comparing the effects of welding parameters on the results, welding pressure had the best effect on tensile strength, and plate surface temperature had the most significant effect on the welding profile geometries.

Effect of Welding Parameter on the Nugget Overlap and Nugget Formation in Resistance Seam Welding of Secondary Coated Steels

Effect of Welding Parameter on the Nugget Overlap and Nugget Formation in Resistance Seam Welding of Secondary Coated Steels

Research on the Welding Process and Weld Formation in Multiple Solid-Flux Cored Wires Arc Hybrid Welding Process for Q960E Ultrahigh-Strength Steel.

This paper proposes a novel welding process for ultrahigh-strength steel. The effects of welding parameters on the welding process and weld formation were studied to obtain the optimal parameter window. It was found that the metal transfer modes of solid wires were primarily determined by electrical parameters, while flux-cored wires consistently exhibited multiple droplets per pulse. The one droplet per pulse possessed better welding stability and weld formation, whereas the short-circuiting transfer or one droplet multiple pulses easily caused abnormal arc ignition that decreased welding stability, which could easily lead to a "sawtooth-shaped" weld formation or weld offset towards one side with more spatters. Thus, the electrical parameters corresponding to one droplet per pulse were identified as the optimal parameter window. Furthermore, the weld zone (WZ) was predominantly composed of AF, and the heat-affected zone (HAZ) primarily consisted of TM and LM. Consequently, the welded joint still exhibited excellent mechanical properties, particularly toughness, despite higher welding heat input. The average tensile strength reached 928 MPa, and the impact absorbed energy at -40 °C for the WZ and HAZ were 54 J and 126 J, respectively. In addition, the application of triple-wire welding for ultrahigh-strength steel (UHSS) demonstrated a significant enhancement in post-weld deposition rate, with increases of 106% and 38% compared to single-wire and twin-wire welding techniques, respectively. This process not only utilized flux-cored wire to enhance the mechanical properties of joints but also achieved high deposition rate welding.

Influence of welding parameters on the formation of U-rib fillet welds in single-sided welding of steel bridge panels

It is difficult to reach the requirement of 80% U-rib weld penetration in the practical application of single-sided welding of steel bridge panels. Meanwhile, full penetration has to be avoided. In this study, efforts are made in order to achieve fillet welds with 80% and above penetration consistently. The effect of welding parameters on the formation of single-sided U-rib fillet welds is investigated. This work has revealed that U-rib fillet weld penetration is presenting an upward trend as the welding current increases under specific welding conditions, and full penetration was observed at the current of 325 A. With the increasing distance between the filler wire and the root of the weld, the U-rib penetration reduces. As the torch angle increases during ship position welding, the U-rib penetration will first increase and then decrease. The weld formation of flat position welding is more stable and the U-rib weld penetration has been significantly improved. The optimum U-rib weld with penetration of 84.8% is achieved under the conditions of flat position welding with 285 A welding current, 44∘ torch angle, and 2[Formula: see text]mm distance between the wire and the root.

Artificial Neural Networks and Experimental Analysis of the Resistance Spot Welding Parameters Effect on the Welded Joint Quality of AISI 304.

The automobile industry relies primarily on spot welding operations, particularly resistance spot welding (RSW). The performance and durability of the resistance spot-welded joints are significantly impacted by the welding quality outputs, such as the shear force, nugget diameter, failure mode, and the hardness of the welded joints. In light of this, the present study sought to determine how the aforementioned welding quality outputs of 0.5 and 1 mm thick austenitic stainless steel AISI 304 were affected by RSW parameters, such as welding current, welding time, pressure, holding time, squeezing time, and pulse welding. In order to guarantee precise evaluation and experimental analysis, it is essential that they are supported by a numerical model using an intelligent model. The primary objective of this research is to develop and enhance an intelligent model employing artificial neural network (ANN) models. This model aims to provide deeper knowledge of how the RSW parameters affect the quality of optimum joint behavior. The proposed neural network (NN) models were executed using different ANN structures with various training and transfer functions based on the feedforward backpropagation approach to find the optimal model. The performance of the ANN models was evaluated in accordance with validation metrics, like the mean squared error (MSE) and correlation coefficient (R2). Assessing the experimental findings revealed the maximum shear force and nugget diameter emerged to be 8.6 kN and 5.4 mm for the case of 1-1 mm, 3.298 kN and 4.1 mm for the case of 0.5-0.5 mm, and 4.031 kN and 4.9 mm for the case of 0.5-1 mm. Based on the results of the Pareto charts generated by the Minitab program, the most important parameter for the 1-1 mm case was the welding current; for the 0.5-0.5 mm case, it was pulse welding; and for the 0.5-1 mm case, it was holding time. When looking at the hardness results, it is clear that the nugget zone is much higher than the heat-affected zone (HZ) and base metal (BM) in all three cases. The ANN models showed that the one-output shear force model gave the best prediction, relating to the highest R and the lowest MSE compared to the one-output nugget diameter model and two-output structure. However, the Levenberg-Marquardt backpropagation (Trainlm) training function with the log sigmoid transfer function recorded the best prediction results of both ANN structures.

Springback Optimization of Dissimilar Thickness AA6061-T6 Blank Joint with Double Butt-Lap (DBL) Using Taguchi Method and ANOVA

This study focuses on investigating the effect of welding parameters, specifically spindle speed, feed rate, and tool tilt angle, on the springback of double-butt lap joints blank. To optimize springback of friction stir welded AA6061-T6 blanks with different thicknesses, a Taguchi L9 orthogonal design experiment was utilized. The responses of springback from lines perpendicular and parallel to the welding line were observed, and the optimal parameter combination for each type of springback was determined. Analysis of Variance (ANOVA) revealed that the tilt angle contributed the most to springback (parallel to the weld line) with 50.4%, while the spindle speed contributed the most to springback (perpendicular to the weld line) with 52.5%. Through confirmation testing, the optimal FSW parameters were validated.

Stress biaxiality-based residual stress assessment in welded T-joints using the blind-hole method

The blind-hole method is widely used to measure the welding residual stress (WRS) in welded steel structural connections such as T-joints. To enhance the test accuracy, a rapid WRS evaluation method considering stress level and biaxial stress ratio was developed and validated. The proposed method was applied to measure the WRS distributions of T-joints in steel truss bridges, and a finite element model (FEM) simulating the WRS was verified by the test results. On this basis, the effects of welding parameters and geometric configuration of T-joints on WRS were analyzed by the validated FEM. The results show that the maximum error from ignoring the hole edge plasticity or stress biaxiality is about 20%, and the proposed method can effectively reduce the WRS measurement error caused by the above factors. The results of the experiment and FE analysis demonstrate that the WRSs in T-joint are in an obvious biaxial stress state, which further proves that it is necessary to consider stress biaxiality in calibration for the blind-hole method.

Effects of welding parameters and thermal insulation on the mechanical behavior and microstructure of friction lap-welded aluminum to glass fiber–reinforced thermoset composite with a thermoplastic PA6 interlayer

Effects of welding parameters and thermal insulation on the mechanical behavior and microstructure of friction lap-welded aluminum to glass fiber–reinforced thermoset composite with a thermoplastic PA6 interlayer

Effect of welding parameters on microstructure, mechanical properties and environment

Welding methods are one of the promising methods to join similar or dissimilar materials. In particular, Tungsten Inert Gas (TIG) welding is widely used in the field of industry. However, correct selected parameters and their effect on the environment are important factors in obtaining a good metal join. The aims of this study to investigate the role of the filler and heat treatment on mechanical properties of the similiar joint 6061 Aluminum, and also discuss the effect of this method on the enviroment based on literature review. Three different fillers consist of ER 4043, ER 4047, ER 5556 and artificial aging with temperatures of 125°C, 155°C, 185°C respectively were conducted using TIG welding. To investigate mechanical properties, the Vickers hardness, tensile test and also microstructure observations were carried out at room temperature. The result shows that the maximum hardness is 91.6 HV and the tensile strength is 180 MPa obtained by using filler ER 5556. On the other hand, artificial aging successfully enhances the mechanical properties of the 6061 aluminum welding.

Effect of welding parameters on cruciform weld joints made of armor steel

Abstract It is aimed to examine the effect of welding parameters on cruciform welded joints. Armor steels are used in military applications such as tracked and wheeled armored vehicles. These steels are quenched and tempered steels and have high yield stress and hardness. Although the increase in carbon equivalent increases the ballistic level together with the hardness value, weldability decreases. Therefore, the welding parameters of these steels must be determined carefully. Before the welding, chemical analysis, macro examination, hardness test, tensile tests and ultrasonic examination were carried out to verify the material properties. After the verification tests, plates were welded with three different welding parameters to observe the changing of the mechanical properties. After the welding process, welded pieces were subjected to non-destructive tests to inspect the weld imperfections. After the inspection, welded specimens were subjected to hardness test, macro examination and tensile tests. In addition to these tests, weld penetration (WP) measurements were performed with a new assessment method. In this measurement method, unit of area takes into consideration instead of the unit of length. As a result, it is determined that with the increasing welding parameters although WP increase, hardness values in heat affected zone decrease.

Microstructure evolution of the Zr-4 alloy joints diffusion bonded with pure titanium interlayer and its influence on joint properties

Zirconium-based alloy is widely applied as the fuel cladding material. Its weld needs high precision and small deformation, so the low-temperature bonding is a crucial issue to be addressed. In this study, we used pure titanium interlayer to join Zr-4 alloys by diffusion bonding at low temperature. A sound joint with pure titanium interlayer was bonded at 680 °C, which was 70 °C lower than that of the direct bonding. The effect of welding parameters on the microstructure and phase composition was investigated by scanning electron microscope (SEM) with energy dispersive spectroscopy (EDS), and transmission electron microscope (TEM). Four solid solutions, (hexagonal close-packed) hcp-Ti0.92Zr0.08, hcp-Ti0.7Zr0.3, hcp-Ti0.5Zr0.5, and (body-centered cubic) bcc-Ti0.5Zr0.5, were identified forming at the Ti/Zr interface by EDS and TEM analysis. The nanohardness and Young’s modulus were measured by nanoindentation. The highest and lowest nanohardness values across the joint were 5.65 GPa for the hcp-Ti0.7Zr0.3 phase, and 4.09 GPa for the bcc-Ti0.5Zr0.5 phase, respectively. The fracture initiated in the bcc-Ti0.5Zr0.5 phase, prolonged at the Ti/Zr interface because of incoordination in the deformation process of two phases, and then the transverse tearing occurred in the hcp layer. The shear strength initially increased and then decreased as the increasing parameters. The maximum shear strength reached 255 MPa of the joint bonded at 750 °C for 60 min under 15 MPa. Besides, the formation mechanism of the Ti/Zr interface was revealed for the Zr-4 alloy joint with pure titanium interlayer.

Assessment of dissimilar friction stir welded AA6061/SS316 for sustainable industry

Energy and environmental issues have played an important role in developing sustainable industries. The incorporation of lightweight materials into various structures enables a reduction in both weight and fuel consumption, resulting in saving energy. So, the selection of material and joining techniques have contributed significantly in these problems. This paper focused on the assessment of dissimilar lap-joint between AA6061 to SS316 using green technology as friction stir welding. The effect of welding parameters on the properties of joints was assessed. The test results showed that the welding interface is sensitive to rotational speed. The joint with the highest strength is approximately 6200 N at 700 rpm. In this case, the joint was fractured in heat effected zone on the aluminum side. The welding interface was revealed by using scanning electron microscope and energy-dispersive X-ray spectroscopy images to analyze the joint quality.

The effects of laser welding parameters on weldability and quality of the microstructure of additively manufactured Inconel 718-316L joints

Additive manufacturing of metals is a way of producing high-quality end-use parts. Technical alloys, for example Inconel 718, can be used to obtain a lot of benefits for example wear, corrosion, and heat resistance. Laser welding of Inconel 718 is a standard process, but there is rather limited amount of information of welding of additively manufactured nickel superalloys to the additively manufactured stainless steel. The process parameters need to be considered in laser welding. Undesired microstructure can occur due to wrong heat input during the welding process. This study examines laser welding of additively manufactured Inconel 718-316L parts and the effects of the welding parameters to the quality of the weld by analysing microstructure from the heat affected zone. This is done to achieve better part quality more cost efficiently compared to traditionally produced parts and to optimize the welding parameters. It is not feasible to manufacture the full large structure with IN718 and AM could be used to manufacture just the functional parts of the assembly. Tests have shown that welding heat input and cooling time affect to the quality. Inconel 718 hardness decrease across the fused zone because of the mixing of different elements in the molten weld pool. Laser welding highlights cuboidal shaped niobium rich carbides throughout the material to the heat affected zone grain boundaries on Inconel side.

Electron-Beam Welding Joint Strength of Dissimilar Materials

This paper provides an in-depth discussion of the joint strength of electron beam welding of dissimilar materials. The effect of welding parameters and material properties on the joint strength was analyzed, and an argument for the optimal parameter combination is presented. Electron-beam welding technology offers several advantages, including high energy density and the ability to create fine weld seams. However, it also presents certain challenges, such as the complexity of welding parameters and the potential generation of brittle phases. The analysis conducted in this paper holds significant importance in enhancing the quality and efficiency of dissimilar material welding processes.

Effect of process parameters on the mechanical behavior of additively manufactured and FSW joined PLA wood sheets

AbstractFriction stir welding (FSW), a solid‐state joining method, is an innovative technique widely employed in the welding of thermoplastics, with broad application areas such as the automotive and aerospace industries. Due to its inherent advantages, including ease of processing, biodegradability, and printability, polylactic acid (PLA) and its derivatives are notably the most commonly used polymers in 3D printing. The limited print area of 3D printers necessitates post‐production joining processes. In this study, the weldability of plates obtained using PLA Wood filament through the FSW is evaluated. For this purpose, different pin geometries (triangle, square, and screw), feed rates (20, 40, and 60 mm/min), and tool rotation speeds (1250, 1750, and 2250 rpm) are employed. Visual inspections are conducted to determine the effects of process parameters on weld quality and to identify defects in the weld region. Temperature values are measured to investigate the influence of heat generated during the FSW process. Furthermore, after determining the highest weld strengths achieved for each pin geometry, the weldability of PLA Wood material with PLA‐CF and PLA Plus materials is investigated using these parameters. The results indicate that the highest weld quality for joining PLA Wood plates is achieved using the square pin geometry, 20 mm/min feed rate, and 1750 rpm with an efficiency of 74.5%. When welding PLA Wood with PLA‐CF and PLA Plus, high weld strengths are obtained using the same process parameters (square pin, 20 mm/min, and 1750 rpm).Highlights Friction stir welding process of 3D printed PLA Wood material. Friction stir welding process of dissimilar materials pairs. Effect of welding parameters on weld strength and hardness. Identifying the fracture surface images occurring in parts after friction stir welding. Examination of temperature generation during friction stir welding.

The effects of welding parameters on metal transfer and bead properties in the variable-polarity GMAW of mild steel

The effects of welding parameters on metal transfer and bead properties in the variable-polarity GMAW of mild steel

Properties study on Ti/Al butt joining by GMAW/GTAW hybrid welding-brazing

For adjusting the distribution of welding heat to obtain sound Ti/Al butt joints, Gas Metal Arc Welding (GMAW)/Gas Tungsten Arc Welding (GTAW) hybrid welding-brazing was introduced to join 5A06 to TC4. Then two kinds of tensile strength was tested. And the weld microstructure was observed by Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Energy Dispersive Spectrometer (EDS). Effects of welding parameters on weld reinforcement and interface characteristics were investigated. Results revealed TiAl3 IMCs layer was formed in the weld area of the titanium alloy side. The other area of weld was composed of α-Al matrix and Mg2Si+Al+Si eutectic. The back welding reinforcement was improved with the welding heat of the joint back increasing. But this may lead to a large number of molten metal flowing to the back of weld, the face reinforcement of the weld became poor. However, effects of welding parameters on the interface bonding strength was different. It was depended on the thickness and morphology of IMCs. When serrated IMCs of 2–6μm thickness were formed, the highest tensile strength without reinforcement was 240.3 MPa. Through comprehensive analyzing, when the welding parameters were welding speed of 15 mm s−1, GTAW current of 80–90 A and GMAW/GTAW position of −1 mm, the weld reinforcement and interface bonding strength were also high. So the excellent butt joints of TC4/5A06 were achieved. The maximum average value of TC4/5A06 joints tensile strength with reinforcement was 265 MPa with fracture inside the weld far from IMCs layer.