Welding Tool Research Articles

КОМПЬЮТЕРНОЕ МОДЕЛИРОВАНИЕ ТЕМПЕРАТУРНЫХ ПОЛЕЙ В СВАРНОМ ШВЕ ПРИ ИЗМЕНЕНИИ ТЕХНОЛОГИЧЕСКИХ ПАРАМЕТРОВ СВАРКИ ТРЕНИЕМ С ПЕРЕМЕШИВАНИЕМ АЛЮМИНИЯ И МЕДИ

This paper discusses numerical modeling of temperature fields in friction stir welding (FSW) of aluminum (AD1) and copper (M1). A three-dimensional thermomechanical finite element model based on the coupled Euler-Lagrange (CEL) approach is used. The paper models and experimentally confirms the influence of FSW parameters on the distribution and peak temperature values in weld zones. The maximum temperature values are observed on the copper side. This is due to the high thermophysical properties of copper compared to aluminum. Changing the rotation speed of the welding tool from 800 rpm to 1000 rpm leads to an increase in the peak temperature from 492 °C (800 rpm) to 692 °C on the side of the copper plate (1000 rpm). The maximum discrepancy between the calculated and experimental temperature curves does not exceed 9%, which is quite acceptable for assessing the temperature field.

Determination of the load acting on the probe by separating force and torque during FSW of AA 6060 T66

AbstractThe development of suitable welding processes is required to meet the ever-increasing demands on joining processes, particularly for lightweight construction and increasing environmental awareness. Friction stir welding (FSW) represents a promising alternative to conventional fusion welding processes, particularly for the joining of low-melting-point materials such as aluminium and magnesium alloys, which present a number of challenges, including the formation of pores and the occurrence of hot cracks. The central element of the process is the friction stir welding tool, which consists of a shoulder and a probe. The rotation and the simultaneous application of pressure during the joining process create a friction-based heat input through the tool. The excellent mechanical properties resulting from dynamic recrystallisation during the welding process are a major advantage of the process. As a result, strengths comparable to those of the base material can be achieved. However, FSW is subject to process-specific challenges, including high process forces, which result in the fabrication of complex and robust devices. Additionally, high dynamic loads on the friction stir welding tools must be considered. In many cases, the design of friction stir welding tools is based on empirical data. However, these empirical values are machine-, component- and material-specific, which often results in under- or overmatching of friction stir welding tools. Sudden probe failure, component scrap, and low process reliability are the direct consequences of undermatching. Overmatching results in enlarged tools with limited accessibility, high heat input, and high process forces, leading to component deformation. The aim of this study is to determine the load on the probe by separating the forces and torque of the shoulder and the probe in order to be able to make statements about the load acting on the probe and the resulting stress state. The knowledge of the stress state can be employed to design friction stir welding tools, both statically and dynamically, for a specific welding task. A strategy was devised to distribute the load exerted on the shoulder and probe. To this end, the length of the probe was gradually reduced between the welding tests. The investigations were carried out with a force-controlled robotized welding setup in which AA 6060 T66 sheets with a thickness of 5 mm were welded. A Kistler multicomponent dynamometer type 9139AA allows to measure the Cartesian forces to be recorded in the x-, y-, and z-directions with a sampling rate of 80 kHz. The weld seam properties were determined by visual and metallographic inspections as well as tensile and bending tests in accordance with DIN EN ISO 25239–5.

Physical Simulations of the Tool Degradation in Friction Stir Welding

Abstract The present investigation is part of a comprehensive failure study of friction stir welding (FSW) tools, where experimental non-destructive and destructive evaluations are combined with analytical- and physical- simulations of tool wear mechanisms. This paper focuses on the research methodology and the primary results of Gleeble simulations of thermal- and mechanical-cycle effects on an H13 steel material widely used for FSW tools for welding aluminum and magnesium alloys.

Thermal and Frequency Response Analysis on Friction Stir Welding Tool with Different Materials by Using FEA Method

Friction stir welding (FSW) is a solid-state joining technique that joins two facing workpieces without melting the workpiece material. It makes use of a deceased item. The region surrounding the FSW tool softens due to heat produced by friction between the revolving tool and the workpiece material. We are now working on specialised applications (lap and butt welding) while concentrating on test sorts. In addition to being faster than the state of the art, both provide lap welds that are 190% of the plate thickness, improve weld honesty, and lessen upper plate decline. Friction stir welding, or FSW for short, is a popular solid state joining method for soft materials like aluminium alloys. For stronger alloys like steel and titanium alloys, the FSW process's economic sustainability hinges on the creation of long-lasting, moderately cost equipment that reliably yields welds with outstanding structural integrity. The performance of the tool, weld quality, and cost are all impacted by material design and choice. This research reviews and critically examines many key FSW tool components, including process economics, geometry and load bearing capacity, frequency response analysis, tool degradation mechanisms, and tool material selection. The Finite Element Method (FEM) approach is used to characterise the process and provide a more comprehensive knowledge of the thermal effects and thermal inaccuracies on the tool materials.

Wire-based directed energy deposition (DED-wire) used as additive manufacturing technology for industrial Inconel 718 tools for robotic friction stir welding (R-FSW)

Wire-based directed energy deposition (DED-wire) used as additive manufacturing technology for industrial Inconel 718 tools for robotic friction stir welding (R-FSW)

Characterization and analysis of conduction welded thermoplastic composite joints considering the influence of manufacturing

Thermoplastic composite welding is a key technology that can help to make the aviation industry more sustainable, while at the same time enable high-volume production and cost-efficient manufacturing. In this work, characterization, testing and analysis of thermoplastic composite conduction welded joints is performed while accounting for the influence of the manufacturing process. Test specimens are designed from welds of a half a meter long welding tool that is developed to weld the stiffened structures of the next-generation thermoplastic composite fuselage. In the design, special attention is paid to the weldability of the laminates, while ensuring fracture occurs only at the welded interface. Two specimen configurations are evaluated for the Double Cantilever Beam and End-Notched Flexure characterization tests. Moreover, Single Lap-Shear specimens are tested in tension and in three-point-bending. Finally, the characterized material properties are introduced in finite element analyses to demonstrate that the cohesive zone modeling approach can be used to conservatively predict the strength of these welded joints. New insights are obtained in the relation between the manufacturing process, the quality of the weld and the mechanical properties of the joints, which are significantly different compared to autoclave consolidated composites.

Research on Friction Performance of Friction Stir Welding Tools Based on Non-Smooth Structure.

In this study, based on the principles of bionics, we fabricated a bionic non-smooth concave pit structure on the shoulders of friction stir welding tools and detected the thermal cycling curve, downforce, and torque of the tool in the welding process. We tested the wear loss weight and analyzed the surface morphology of the shoulder surfaces after welding for 200 m. This study found that as the distance between the concave pits decreased and the number of concave pits increased, the maximum downforce, torque, and temperature in the welding process showed a decreasing trend. As the speed increased, no matter how the tool structure changed, the downforce and torque decreased, while the peak thermal cycle temperature increased. The experimental welding results show that the wear loss weight of the non-smooth structure tool significantly reduced. The lowest wear loss weight of the tool with a concave pit interval of 1.125 mm was only 0.1529 g, which is 27% lower than that of the conventional tool. Our observations of the surface morphology of the tool shoulder after welding showed that the amount of aluminum swarf on the tool shoulder of the welding tool gradually declined with the increasing density of the uneven pits. The lowest number of aluminum chips adhered to a welding tool with a pit distance of 1.125 mm. Therefore, friction stir welding tools with biomimetic structures have better wear resistance and adhesion resistance.

Characteristics of Friction Stir Welding Tool in Consideration of Shape of Cutting Tool

Characteristics of Friction Stir Welding Tool in Consideration of Shape of Cutting Tool

Tribological and mechanical properties of FSW joints of untainted stainless steel and titanium: novel characterization of similar and dissimilar joints

Friction Stir Welding (FSW) is an emerging solid-state welding process that joins dissimilar or similar metals based on requirements. The additional material to make the joint is also a weight reduction factor deemed vital in weight-sensitive industries like aerospace and orthopedic applications. The similar and dissimilar Ti-6Al-3Nb-2Zr-1Mo (Ti6321) and stainless steel (SS 310) joints are performed through friction stir welding. This investigation aims to identify the effect of process parameters on the mechanical behavior and microstructural characteristics of the FSW joints. Five plates are chosen; three are FSW joints, and two are kept in the original base material. In all five plates, tensile, microhardness, and wear tests are performed, including an analysis of grain size. It is observed that the similar Ti6321 joint with a 6 mm pin diameter, 60 mm transverse speed, 900 mm rotational speed, and a constant axial force of 1 KN exhibits a maximum microhardness of 362 HV and a tensile strength of 927 MPa when compared to other joints. The tribological properties are identified as varying load (10–50 N), sliding speed (1–5 m s−1), and a constant sliding distance (1000 m) on pin-on-disc apparatus. It reveals that welding parameters and tool diameter influence tribological characteristics. The surface morphology carried out by FE-SEM revealed that the HAZ is composed of acicular α. The increase in microhardness is higher in WC than in BM due to the uniform distribution of particles. The chemical composition and phases are analyzed using XRD.

Analysis of variance and grey relational analysis application methods for the selection and optimization problem in 6061-T6 flange friction stir welding process parameters

A study was carried out to investigate and enhance the effects of friction stir welding on the mechanical characteristics of a flange composed of 6061-T3 aluminum alloy. The pipes possess an outer diameter and wall thickness of 6 mm, while the plates are sized at 100 x 100 × 6 mm. Nine unique experiments were planned using the Taguchi orthogonal array method, with the welding tool remaining constant. Three independent variables (travel speed, rotation speed, and shoulder diameter) were altered at three different levels for each variable. The research analyzed the influence of various FSW factors on the weld flange joint. Analysis of variance (ANOVA) and grey relational analysis (GRA) were employed to determine the impact of each FSW underwater parameter. Moreover, the statistical Taguchi technique (TM) was used to predict the optimal combination of welding parameters to improve tensile properties, including tensile strength (UTS), yield strength (YS), elongation (EI%), and bending load (BL) of welded joints. Additionally, the actual tests demonstrated a high level of agreement with the results obtained from the proposed mathematical model. The validation results obtained indicate that the optimization method is a dependable tool for enhancing the quality responses of friction stir welding.

Microstructural evolution and corrosion responses of friction stir welded SUS301L stainless steel

As a typical manifestation of elemental segregation of stainless steel, chromium depletion was often brought about by welding, leading to undesirable corrosion resistance. In light of this, we employed friction stir welding through WC-W composite welding tools to achieve sound joints of SUS301L stainless steel, with corrosion resistance exceeding that of the base material (BM). A higher austenite fraction of 20.8% enhanced corrosion resistance since the corrosion potential of austenite is nobler than that of martensite. Austenite was not decomposed into harmful σ-phases due to the shorter holding time at the elevated temperature, thus enhancing the homogeneity of the microstructure. The ultimate tensile strength of the welded joints reached 820 MPa, which was equal to 98.9% of BM. The pitting potential of the joint was increased by 0.078 V, indicating that the stability of the passive films was improved, and the ability to resist the corrosive medium was strengthened. Chromium depletion was eliminated, resulting in no sensitivity to intergranular corrosion.

Use of threaded cylindrical pin tools to reduce macroscopic defects in dissimilar welded joints of AA7075-T6 and AZ31B alloys by the FSW process

The continued increase in greenhouse gas emissions has had dire consequences for the global climate. In order to reduce such emissions, several efforts have been made by researchers in the transport sector, such as the development of electric motorization, the development of hybrid engines, the use of biofuels and the use of light alloys. The use of light alloys such as aluminum and magnesium in vehicles can reduce the emission per kilogram of vehicles drastically, however, it is still necessary to develop effective and more agile methods of the dissimilar joints of these materials. Some authors have studied the friction stir welding of AZ31B magnesium alloys and AA7075-T6 aluminum alloys in order to determine better process parameters to enable this bond, however, few articles have been published in order to evaluate the influence of tool geometry on such properties. In this sense, this article aims to evaluate the influence of friction welding tool pin geometry as smooth cylindrical pin, threaded cylindrical pin, conical and hexagonal pin configurations in the formation of the mixed zone of welds manufactured by the FSW process. For this purpose, AZ31B and AA7075-T6 alloys were welded by FSW with welding speed of 75 mm/min, tool rotation speed of 565 rpm, offset of 0.5mm and inclination of the tool geometry in relation to the plates to be welded of 3º, the joints were evaluated for their macro and microstructures and Vickers hardness with a load of 100 gf. It was possible to observe that the joints welded with the threaded cylindrical pin tool presented stir zones free of macroscopic defects, similar hardness values for the four tools studied and the presence of a thin layer of intermetallics between TMAZ and SZ on the AZ31B side.

Study on the microstructure and properties of spray formed 7055-T76 aluminum alloy joints by rotating magnetic field assisted friction stir welding

This study explores an electrically-magnetically-assisted friction stir welding (EMAFSW) method, conducting butt welding experiments on T76 tempered spray-formed 7055 aluminum alloy. Compared to traditional friction stir welding (FSW) processes, the EMAFSW method maintained basically consistent weld hardness, while tensile strength and elongation increased by 13.1% and 72.3%, respectively. The rotating magnetic field enhanced the mechanical stirring action of the welding tool, reduced the size of precipitates, promoted dislocation pinning, and increased the mobility of dislocations. The stirred zone (SZ) and thermo-mechanically affected zone (TMAZ) of EMAFSW weld joint showed significant grain refinement and increased recrystallization proportion, enhancing the weld joint toughness. The joint's fracture behavior shifted from brittle to ductile fracture.

A realization of Al/Ti dissimilar friction stir welding via bottom dynamic support using a Co-based alloy welding tool

A realization of Al/Ti dissimilar friction stir welding via bottom dynamic support using a Co-based alloy welding tool

Relationship between mechanical behavior and process factors in friction stir welding aluminum alloys

The friction stir welding (FSW) procedure is the main topic of this research study among the various welding techniques. The study focuses on the interaction between the mechanical properties of 3003 aluminum alloy and the process parameters (rotation speed, welding speed, and dwell time) in the form of rolled plates of 2 mm thickness, end-to-end and welded at 90° and 45°. The welds were made by varying the speed of rotation (1000, 2000 rpm) and setting the tool feed at 500 mm/min. This experimental approach is also based on varying the tilt of the welding tool from 0° to 2°. It has been shown that the studied parameters play an important role in the characterization and optimization of the above mentioned weld joints. Therefore, and based on the results obtained, the use of the 90° joint remains the best in terms of strength.

Investigation on the mechanical properties and microstructural analysis of dissimilar friction stir welding of AA5154/AA7150

Butt welds were produced on AA5154/AA7150 using the FSW method, and measurements were taken for the hardness and elongation percentage of each joint. Regression analysis was utilized to investigate the significance of each parameter and formulate a mathematical relationship. Welding was performed at 1200 rpm, with a welding speed of 90 mm/min and a tool diameter of 28 mm, resulting in defect-free welds. Failures were commonly observed at the pin and the side of AA7150. To decrease the ultimate tensile strength (UTS), the welding speed (WS) or tool rotational speed (TRS) was increased. As both TRS and WS constitute the nugget zone, variations in hardness distribution were noted across the weld zones. ANOVA was applied in this study to establish the relative importance and influence of each factor on UTS. The ANOVA results indicated that all parameters significantly impacted UTS. Specifically, WS contributed 41.42%, diameter contributed 17.57%, and TRS contributed 13.27%. A quadratic model was also developed to describe the relationship between the factors and UTS values. Based on the data, a range of 0.41% to 10.36% differences existed between projected and actual values. The strength of the model was evaluated using R-Squared (R-Sq.), resulting in an obtained R-Sq. value of 0.892. This value indicates a robust relationship between the predicted and actual values.

Enhancing Friction Stir Welding: Quality Machine Learning Based Friction Stir Welding Tool Condition Monitoring

Ensuring the quality and optimizing the tool in Friction Stir Welding (FSW) process is quite complex and the solution relies on implementing Condition Monitoring. The major impact of this process yields good quality welds and cuts down the non-operational timing and cost. Condition Monitoring is the key to find a solution to the challenging problem of ensuring quality and optimizing the tool in the FSW process. The creation of a graphical user interface (GUI) and the development and comparison of several models, including Decision Tree (DT), Random Forest (RF), Light Gradient Boosted Machine (LGBM), and Extreme Gradient Boosting (XGBoost), are the main objectives of this study. By offering an uniform interface for tracking and evaluating tool condition data, GUI can make it easier for operators and the maintenance crew to collaborate. Vibration analysis is the first step in tool condition monitoring. Al5083 and AZ31B are used as the workpiece and H13 as the tool in this investigation. The signals are obtained from the experimental setup via DAQ, and LabView processes them. A Python script converts the raw signals into statistical data. Following that, the data was loaded into ML models and optimized using Optuna. TKinter has been used to create the GUI. For prediction, the best models were included in the GUI. By the deployed models, LGBM generates 96% for 1000 rpm, 96.55% for 1200 rpm, and 95.90% for 1400 rpm for Al5083 93.22% for 1000 rpm, 99.29% for 1200 rpm, and 91.50% for 1000 rpm for AZ31B. For real-time prediction, these models are thus connected to a graphical user interface. In each case, the LGBM classifier topped the others. This work served as an initial basis for the creation of a semi-onboard diagnostic approach that requires minimal human input.

Optimizing Micro Friction Stir Spot Welding (mFSSW) of Aluminum Alloy AA1100 Using Neural Network Model

This study explores the optimization of Micro Friction Stir Spot Welding (mFSSW) by investigating the influence of tool profiles on welding outcomes, using aluminum alloy AA1100 with a 0.42 mm thickness as the specimen material. Monitoring temperature and RPM during welding with thermocouples and tachometers, mechanical properties are assessed through tensile shear tests, microhardness measurements, and macrostructural observations. The findings serve as the basis for developing Neural Network models using Rapidminer software, marking a transformative development that positions Neural Networks as potent tools for optimizing welding processes, potentially leading to achieving optimal weld quality. The investigation also delves into three welding tool configurations – the two-stage pin, one-stage pin, and pinless mFSSW probes – highlighting their distinct impacts on tensile shear test values and overall welding quality. Notably, the two-stage pin configuration emphasizes the significance of larger pin diameters and controlled heat generation for enhanced weld strength, while the one-stage pin configuration underscores the pivotal role of pin diameter and elevated temperatures in improving weld quality. The pinless mFSSW probe configuration, on the other hand, emphasizes the importance of shoulder diameter and temperature control for superior tensile shear test results. Leveraging Neural Network modeling for optimization, this study advances our understanding of parameter interactions and underscores the efficacy of Neural Networks in achieving superior tensile shear test values and welding quality in mFSSW, offering valuable insights for future endeavors in the field..

Investigating the effect of welding tool length on mechanical strength of welded metallic matrix by molecular dynamics simulation

The welding process and the properties of welding instruments may improve the mechanical performance of an item. One of these properties is the length of the welding tool. This approach has a substantial effect on the mechanical strength of the metallic matrix. The current study used molecular dynamics modeling and LAMMPS software to evaluate the effect of welding tool length on the mechanical properties of a welded Cu–Ag metallic matrix. This simulation makes use of the Lennard-Jones potential function and the embedded atom model. First, the equilibrium phase of modeled samples was verified by changing the computation of kinetic and total energies. Next, the mechanical properties of the welded matrix were studied using the stated Young's modulus and ultimate strength. The stress-strain curve of samples demonstrated that the mechanical strength of atomic samples increased as the length of the welding tool (penetration depth) increased. Numerically, by increasing the tool penetration depth of Fe tools from 2 Å to 8 Å, Young's modulus and ultimate strength of the matrixes sample increase from 34.360 GPa to 1390.84 MPa to 38.44 GPa and 1510 MPa, respectively. This suggested that the length of the Fe welding tool significantly affected the mechanical properties of the welded metallic matrix. The longer the length of Fe welding tools, the more particles were involved, and consequently, more bonds were formed among the particles. Bonding among the particles caused changes in mechanical properties, such as greater ultimate strength. This method can optimize mechanical structures and be useful in various industries.

Visualization of vertical transfer of material through high-velocity rotating flow zone during friction stir welding

In this letter, combined experimental and computational analysis has allowed new understanding of the vertical material flow behaviors during friction stir welding. It is found that a high-velocity rotating flow zone exists near the welding tool, where horizontal and vertical flow are both significant. Material entering the high-velocity rotating flow zone migrates to the lower location of the workpiece after multiple rotations. Material outside the high-velocity rotating flow zone bypasses the tool and migrates towards the upper locations. The findings of this research offer insights into the regulation of microstructures and the formation of defects in FSW.