Torch Angle Research Articles

Effect of combined parametric impacts on collapsing the wall quality of WAAM Al5356 component

Even though Wire and Arc Additive Manufacturing (WAAM) of the Al5356 component has garnered attention for making affordable, large-scale components, problems with porosity, humping, and undercut still exist. Therefore, optimising process parameters is crucial to achieving flawless products with consistent layer deposition. Hence in this research, the most important WAAM parameters including travel speed (TS), wire feed speed (WFS), and torch angle (TA), were examined in order to determine how they affected structural integrity while taking into account key responses such as porosity, pore diameter, and tensile strength. The Significance of Criteria Weighted Aggregated Sum Product Assessment (WASPAS) in conjunction with Intercriteria Correlation (CRITIC) was used to investigate the favourable circumstances and confirm that the TA is the most important parameter in the nucleation of pores. The verification studies demonstrate that a 58.2 % reduction in pore diameter results in a 31.8 % increase in tensile strength. An ideal TS and WFS of 65 cm/min and 5 m/min, with a maximum TA of 90°, were found to be the favorable conditions for printing Al5356 wall with a minimum porosity of 0.037 %, enhanced ultimate tensile strength of 278 MPa, and minimum pore diameter of 93 µm, according to the CRITIC associated WASPAS approach. Additionally, using the fractography, the damage process based on the porosity creation was investigated. The optimal parameters for generating a defect-free multi-layer structure were identified, hence enhancing the structure’s suitability for industrial use.

Insight into Role of Arc Torch Angle on Wire Arc Additive Manufacturing Characteristics of ZL205A Aluminum Alloy.

The arc torch angle greatly affected the deposition characteristics in the wire arc additive manufacturing (WAAM) process, and the relation between the droplet transition behavior and macrostructure morphology was unclear. This work researched the effect of torch angle on the formation accuracy, droplet transition behavior and the mechanical properties in the WAAM process on a ZL205A aluminum alloy. The results suggested that at the obtuse torch angle, part of the energy input was used to heat the existing molten pool, which was optimized for the longer solidification period of the molten pool. Therefore, the greater layer penetration depth at 100° resulted in the improved layer-by-layer combination ability. The obtuse torch angle was associated with the better formation accuracy on the sidewall surface due to the smaller impact on the molten pool, which was influenced by both the arc pressure and droplet impact force. The eliminated pores were optimized for the mechanical properties of depositions at a torch angle of 100°; thus, the tensile strength and elongation attained maximum values of 258.6 MPa and 17.1%, respectively. These aspects made WAAM an attractive mode for manufacturing large structural components on ZL205A aluminum alloy.

Additive manufacturing of Fe28.2Mn32.9Ni18.8Cr6Al14.1 high-entropy alloy by applying consumable fillers of metal powders and polyvinyl alcohol

Simultaneous application of welding methods and metal additive manufacturing facilitates the production of various 3D physical samples from metals and alloys. One of the technical impediments, especially for additive manufacturing of high entropy alloys, is the variety of elements in their chemical composition that makes the fabrication of fillers in welding methods very challenging. In the present research, the additive manufacturing of Fe28.2Mn32.9Ni18.8Cr6Al14.1 high entropy alloy with the use of consumable fillers, including metal powders and polyvinyl alcohol binder through gas tungsten arc welding process has been investigated. To perform the gas tungsten arc welding process, the experiments were designed using the Taguchi method. The parameters of current, torch angle, torch speed, and substrate temperature were selected as the input parameters. Then, through Grey analysis, the optimum width and height of the weld bead were determined to deposit thin layers with high height and low width. The results of the experiments confirmed that the proposed method for fabricating consumable fillers successfully performed layer-by-layer deposition of the sample using the gas tungsten arc welding process. Moreover, the elemental mapping images proved the presence of all elements in the Fe28.2Mn32.9Ni18.8Cr6Al14.1 sample. Furthermore, no internal voids were detected upon inspection of the fabricated sample using a micro-computed tomography scanner.

Dissimilar joining of AZ31B and Ti–6Al–4V sheets in lap joint using cold metal transfer welding

Ti–6Al–4V and AZ31B alloy sheets were joined in lap joint configuration using cold metal transfer welding with a synergic power source. The torch angle was kept approximately 45° away from the top plate. Wire feed speeds (WFSs) have been varied from 3.0 m/min to 7.0 m/min. Cold metal transfer welding results in good deposition of weld metal at higher WFSs but at the cost of poor bonding and defects. Joints of the best qualities were fabricated at a WFS of 3.0 m/min and a welding speed of 0.6 m/min. The torch angle assisted in the proper deposition of AZ31B weld metal with a good bond between weld metal and Ti–6Al–4V base metal. Microstructural analysis confirms the joint interface integrity by revealing the absence of defects. Also, there is a significant variation among the grain morphology of weld region, transition zone and base metal. The presence of several oxides (MgO4, Al2O3, etc.) and intermetallics (Mg17Al12, Mg7Zn3, AlMg4Zn11, etc.) is indicated by metallurgical analyses. Tensile-shear tests revealed that the joints could sustain the maximum load of 1871 N. Fractography reveals the mixed mode of fracture containing majority brittle, and a ductile failure at a few locations. The unusual fracture at a few locations indicates the presence of oxides in these regions.

RESEARCH STATUS AND PROSPECTS FOR TIG-MIG HYBRID-ARC-WELDING TECHNOLOGY

TIG-MIG hybrid welding integrates the merits of tungsten insert-gas welding (TIG) and metal inert-gas welding (MIG), and achieves a new material-joining process with high quality, high efficiency and low cost. However, TIG-MIG hybrid welding also had some shortcomings, such as a complex process, unstable arc, large heat input, limiting its application. To further improve and promote TIG-MIG hybrid welding, numerous universities and research institutes have put forward a series of improvement programs that achieve relatively good results. In this study TIG-MIG hybrid welding is discussed in three aspects: the welding-process improvement, welding-parameters optimization and numerical simulation of the welding process. It was found that the stability of the hybrid arc welding process and the quality of the weld bead can be improved by improving the current polarity, wire type and arc swing. The TIG current, the distance between the wire and tungsten, and the heat input had an important impact on the weld quality and the formation of defects. A numerical simulation of the welding process analyzed the effects of torch angle, the distance between the wire and tungsten, the welding speed and the temperature fields on the arc morphology, molten-pool behavior, and droplet transfer. According to the above analysis, it summarized the current research status of TIG-MIG hybrid welding, and then proposed future research directions based on the existing shortcomings and deficiencies.

Mechanical and microstructural characterization of AISI SAE 4130 steel welded joints made by robotic gas metal arc welding process: influence of electrode work angle in 'T' welded joints

Microstructural variations within welded metals, specifically in terms of phases and their corresponding volume fractions, play a crucial role in influencing weld strength and other mechanical properties. Welded joints in a ‘T’ configuration pose a unique challenge due to the dynamic heat distribution caused by changes in the electrode work angle (EWA) between perpendicularly aligned plates. This study focuses on characterizing the microstructure and micro-hardness of ‘T’ welded joints in a 6 mm thick plate of AISI SAE 4130, welded using the robotic gas metal arc welding process. The examination covers three distinct zones: the base material (BM), the fusion zone (FZ), and the heat-affected zone (HAZ). The extent of the HAZ is meticulously measured on both the vertical and horizontal plates within the weld zones. The x-ray diffraction (XRD) analysis results indicated that the average crystallite size of the base metal and fusion zone is 25.75 nm and 24.51 nm respectively. As per the scanning electron microscope (SEM) image observations, the higher wire feed rate yields to brittle fracture surface. The torch angles notably influence the dimensions of the HAZ on the vertical and horizontal plates of a ‘T’-Joint. Welding at higher EWA and contact-tip-work-distance, results in a larger HAZ on the vertical plate. Conversely, employing a flattened EWA and an increased contact-tip-work-distance leads to a greater extent of the HAZ on the horizontal plate. Furthermore, the micro-hardness of the fusion zone and heat-affected zone demonstrates an increase at higher settings of wire feed rate and travel speed. This phenomenon is attributed to the elevated heat inputs, which contribute to the formation of a finer microstructure within the weldment.

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.

Bead Geometry Control in Wire Arc Additive Manufactured Profile — A Review

Wire arc additive manufacturing (WAAM) is a well-established additive manufacturing method that produces 3D profiles. A better deposition efficiency can be achieved by understanding the parameters that may influence the geometry of the bead. This paper provides a review that focuses on the factors that may influence the formation of the 3D profile. The included factors are the flow pattern of the molten pool after deposition, the built structure and orientation, the heat input and cooling conditions, the welding parameters, and other uncertainties. This review aims to facilitate a better understanding of these factors and achieve the optimum geometry of the 3D parts produced. According to the literature, the behavior of molten pools is identified as one of the major factors that can impact the deposition efficiency of a bead and govern its geometry. The review indicated that the flow behavior of the molten pool and the geometry of the deposited bead are significantly affected by most welding parameters, such as torch angle, wire travel speed, filler feed rate, and cooling conditions. Furthermore, this paper incorporates the technology utilized for comprehending the behaviors of the molten pool, as it constitutes an integral component of the control strategy. It has been concluded that automated planning and strategy are necessary to ensure efficient deposition by controlling those factors. The integration of artificial intelligence could bring benefits in planning to address the variation and complexity of shapes.

Mathematical Modelling to Predict Bead Geometry Parameters of MIG Welded Aluminum 6063 Plates

The purpose of this research is to evaluate the effect of various operational parameters like voltage, weld speed, torch angle, nozzle to plate distance (NPD), and wire feed rate on bead geometry of welds on aluminum 6063 plates. This aluminum grade has a wide range of applications, from industrial to home. The bead geometry properties of a fusion weld are essential from a design standpoint because they affect the joint's mechanical strength and dependability throughout its usage. Bead width (BW), depth of penetration (DOP), and height of reinforcement (HOR) are all essential bead parameters, which need to be considered while commenting on bead geometry of a weld. An experiment series was performed with the statistical technique of design of experiments, using the central composite rotatable design (CCRD) method. This resulted in a mathematical model that correlated bead geometry parameters with various input parameters. RSM (Response Surface Methodology) is used for the graphical analysis of the results obtained. The suggested framework aims to optimize the input variables in order to attain the specified bead parameter values.

Wear Resistance of Fe–Cr–C Hardfacing Deposited by Flux-Core-Double-Wire GTAW in Rubber Wheel Abrasion Test

Abstract The wear resistance of metals can be improved by using the hardfacing technique. Different processes can produce it with the desirable microstructures and mechanical properties. This study presents an original method, flux-core-double-wire of gas-shielded tungsten arc welding, in which wires of different compositions are used simultaneously to obtain different microstructures. The deposition was controlled through the following parameters: welding speed, deposition current, standoff distance, torch angle, and pulse frequency of wire feed. Four coatings were deposited on AISI 1020 steel substrate by combining the cored wires: Fe–Cr–C, Fe–Cr–C–Nb, Fe–Cr–C–Mo–Nb, and Fe–Cr–C–Mo–Ti. The combination of these wires resulted in a hypoeutectic microstructure with niobium and titanium carbides, with an average hardness of 650 HV0.3. The hypereutectic microstructures were formed by different niobium contents, with a microhardness range from 820 to 1,020 HV0.3. The performance of the hardfacing was evaluated in the rubber wheel abrasion test described by ASTM G65, Standard Test Method for Measuring Abrasion Using the Dry Sand/Rubber Wheel Apparatus (Superseded), procedure B. The results revealed that the carbide cracking distinguished the wear resistance, and the hardness was not enough to separate the wear behavior. Still, the volume fraction of carbides was a decisive microstructural parameter.

Optimization of CMT Welding Parameters of Stellite-6 on AISI316L Alloy Using TOPSIS Method

Thisarticle discusses the welding parameters optimization to find the quality of stellite-6 cladding on AISI304L austenite alloy using a new optimization method called Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The experiments(31 nos.) were carried out with the cold metal arc transfer welding method (CMT) based on the central composite design (CCD). The cladding material is the stellite-6 alloy which is appreciated for its corrosion and wear resistance. Four factors (welding current, voltage, welding speed and torch angle) and five levels were considered for the experiment and the optimization. It is necessary to find the optimized parameters for the industrial applications as a huge number of experiments are not recommended. The optimization results showed that the 2nd experiment had the 1st rank with high relative closeness and the 19th experiment was in the last rank. Higher current and low welding speed yielded good results and a low corrosion rate of 0.004582 mm/yr. Furthermore, the Micro-structural, Corrosion study and the SEM-EDS of the specimen produced by the 2nd experiment are discussed here. Cr and Co elements were most abundant, according to an EDS study, in the cladding region.

Mathematical modelling for prediction of angular distortion in the MIG welded Aluminium 6101 plates

Metals are commonly joined using the Metal Inert Gas (MIG) which is also known as the Gas Metal Arc (GMA) welding process in the fabrication industries because of their ability to weld an extensive diversity of metals as well as its alloys and composites. It can also get fully automated which makes it appropriate for mass fabrication. In this process, like other arc welding operations, there is a huge amount of heat input into the workpiece due to which there are rapid and non-uniform heating and cooling cycles involved. This results in the thermally generated stresses transverse to the weld due to which angular distortion is very likely to get introduced. The important input parameters which contribute significantly to the angular distortion are found to be voltage (V), torch angle (TA), wire feeding rate (WFR), nozzle-to-plate distance (NPD) and welding speed (WS). In the present work, the analytical method of design of experiments (DoE) is utilized to develop a mathematical model relating these with the angular distortion on the Aluminium 6101 plates. The fitness of the representation is scrutinized using the ANOVA technique. The graphical representation of the direct and the interactive consequences of input variables on the angular distortion is evolved by utilizing the response surface methodology (RSM) approach.

Line-Structured Light Fillet Weld Positioning Method to Overcome Weld Instability Due to High Specular Reflection

Fillet welds of highly reflective materials are common in industrial production. It is a great challenge to accurately locate the fillet welds of highly reflective materials. Therefore, this paper proposes a fillet weld identification and location method that can overcome the negative effects of high reflectivity. The proposed method is based on improving the semantic segmentation performance of the DeeplabV3+ network for structural light and reflective noise, and, with MobilnetV2, replaces the main trunk network to improve the detection efficiency of the model. To solve the problem of the irregular and discontinuous shapes of the structural light skeleton extracted by traditional methods, an improved closing operation using dilation in a combined Zhang-suen algorithm was proposed for structural light skeleton extraction. Then, a three-dimensional reconstruction as a mathematical model of the system was established to obtain the coordinates of the weld feature points and the welding-torch angle. Finally, many experiments on highly reflective stainless steel fillet welds were carried out. The experimental results show that the average detection errors of the system in the Y-axis and Z-axis are 0.3347 mm and 0.3135 mm, respectively, and the average detection error of the welding torch angle is 0.1836° in the test of a stainless steel irregular fillet weld. The method is robust, universal, and accurate for highly reflective irregular fillet welds.

A Smart Handheld Welding Torch Device for Manual Spot Laser Welding

In producing custom-made systems, using a robotic welding line that can fine-tune welding parameters is not economical, and laser welding is usually done manually. The most common operator error in manual welding operations is the angular positioning error between the laser beam and the plate surface. This study introduces a smart handheld welding torch device that assists the welding operator with visual warnings. It measures the sheet surface angle to eliminate angular positioning errors, calculates the appropriate torch holding angles accordingly, and helps the laser welding process with the right angle. For this purpose, this study focused on micro-laser spot welding applications of stainless (inox) kitchen and hotel equipment, and the effect of angular positioning errors on the welding quality was investigated experimentally. Experiments show that when the angle between the surface normal and the welding torch is smaller than the critical welding angle, heat-induced traces or micro-deformations occur on the visible surface of the thin stainless material. In addition, there is a significant decrease in the weld quality, since a large enough weld area cannot be created at large values of this angle. The optimum torch angle range was determined using experimental results for the available laser welding parameters. With a standard welding torch and the smart torch, the welding operator was allowed to repeat the same task, and the payloads of the samples prepared in this way were measured. Test results show that using a smart welding torch with an angular positioning assist system significantly improves welding quality. Breaking force values vary in a wide range of welds made with a standard welding torch, and visual problems such as burning, puncture, and swelling are encountered on the visible surfaces of many samples with high strength values. When the developed smart torch was used, the breaking force remained within the desired reference range, and no visual defects were found in any sample.

Aluminum alloy and galvanized steel CMT weld joints for lightweight automobile applications

Cold Metal Transfer (CMT) lap joint of Al6061-T6 and Galvanized steel is studied in this paper using design of experiments method. Welding parameters considered for the work includes stick out distance (10 mm −14 mm), wire-feed speed (3.5 m min−1 – 4 m min−1) and torch angle (10˚ to 15˚). Weld strength is optimized by using Taguchi analysis by optimizing input variables with 100% argon gas and stick out distance of 14 mm and overlap region of 13 mm. Weldments were cut in shape and size as per ASTM E8 to perform uni-axial tensile test. Further ANOVA analysis is used to understand the effect of individual parameters & their contribution on weld strength. Result depicted all three input parameter significantly effects the strength. Experiments showed that Al6061-T6 is possible to be welded with the Galvanized-steel using CMT.

Correction to: Effect of torch angle and position on bead geometry and joint strength during arc brazing of thin‑gauge dual‑phase steel

Correction to: Effect of torch angle and position on bead geometry and joint strength during arc brazing of thin‑gauge dual‑phase steel

Finite element investigation on the effect of arc configuration and torch angle on heat distribution in TIG-MIG hybrid welding of DSS 2205

Finite element investigation on the effect of arc configuration and torch angle on heat distribution in TIG-MIG hybrid welding of DSS 2205

The Influence of Heat Input on the Formation of Fatigue Cracks for High-Strength Steels Resistant to Low Temperatures

Welding is one of the most widely used metal joining techniques. However, improper technique and handling may lead to weld defects. Cracks that occur during the exploitation of the welded joints in places of increased stress concentration are called fatigue cracks. In our previous study, we suggested that lowering the stress concentration in the zone of the weld face may prevent surface cracks in butt-welded joints. Here, we further examined how welding heat input and external factors can be controlled to minimize the occurrence of fatigue cracks on welded joints. The fatigue cracks analyzed in this study occurred during the exploitation and are a consequence of the increased stress concentration at the toe of the weld. We performed twenty-four welding experiments comprising the following four welding conditions: torch angle, number of cover passes, length of electrode stick-out, and shielding gas (two environments were used). Stress concentration factors and heat input were determined via experimental data. The results suggested that higher heat input is associated with a lower risk of developing fatigue cracks. Thus, we concluded that fatigue cracks could be minimized by increasing the arc voltage and current while also reducing the welding speed.

Effects of welding parameters on the angular distortion of welded steel plates

Abstract In a welding process, distortion is inevitable and causes a significant problem. Distortion could be minimized up to a specific limit by controlling the welding parameters. The expansion and contraction of the welding metal and the adjacent base metal during the heating and cooling cycles of the welding process create thermal stresses and angular distortion in a welding joint. The welding parameters determine the geometry of a weld bead. The form of the weld bead is vital in the angular distortion of butt welded plates. This article discusses the influence of some flux-cored arc welding process parameters such as shielding gas flow rate, weaving motion of welding electrodes, and torch angle on bead profile and angular distortion of St 37 steel plates of 10 mm thickness. The angular distortion decreases with the torch angle, but it increases with the gas flow rate. The electrode weaving motion consists of three components: the designed weld width, the vertical motion period in the welding direction, and the lateral motion speed normal to the welding direction. The angular distortion decreases with the weld width and the vertical motion period but decreases with the lateral speed.

Effect of torch angle and position on bead geometry and joint strength during arc brazing of thin-gauge dual-phase steel

Effect of torch angle and position on bead geometry and joint strength during arc brazing of thin-gauge dual-phase steel