Search Results (35)

Automating industrial processes, particularly quality inspection, is a key objective in manufacturing. While welding tasks are frequently automated, inspection processes remain largely manual. Advances in computer vision and AI, especially ViTs, now enable more effective defect detection and classification, offering opportunities to automate these workflows. This study evaluates ViTs for identifying defects in aluminum welding using the Aluminum 5083 TIG dataset. The analysis spans binary classification (detecting defects) and multiclass categorization (Good Weld, Burn Through, Contamination, Lack of Fusion, Misalignment, and Lack of Penetration). ViTs achieved 98% to 99% accuracy across both tasks, significantly outperforming prior models such as dense and CNNs, which struggled to surpass 80% accuracy in binary and 70% in multiclass tasks. These results, achieved with datasets of 2400 to 8000 images, highlight ViTs’ efficiency even with limited data. The findings underline the potential of ViTs to enhance manufacturing inspection processes by enabling faster, more reliable, and cost-effective automated solutions, reducing reliance on manual inspection methods. Full article

Combining aluminum and steel offers a promising solution for reducing structural weight and fuel consumption across various industries. Pulse in tungsten inert gas (TIG) weld brazing effectively suppresses interfacial brittle intermetallics and enhances joint strength by influencing pool stirring and heat input during aluminum-to-steel joining. However, optimizing the pulsed TIG weld brazing process is challenging due to its numerous welding parameters. This study established statistical models for Al/steel joint strength without reinforcement using response surface methodology (RSM) based on central composite design (CCD). The models’ adequacy and significance were verified through analysis of variance (ANOVA). The four welding parameters influence weld strength in the following descending order: pulse on time > base current > pulse current > pulse frequency. Additionally, interactions between pulse current and pulse frequency, and between pulse on time and base current, were observed. Numerical optimization using RSM determined the optimal pulsed GTA weld brazing parameters for aluminum and stainless steel. With these optimized parameters, the joint strength reached 155.73 MPa, and the intermetallic compound (IMC) thickness was reduced to 3.4 μm. Full article

The aim of this work is to study joining Al 2024-T3 alloy plates with different welding procedures. Aluminum alloy AA 2024-T351 is especially used in the aerospace industry. Aluminum plates are welded by the TIG and MIG fusion welding process, as well as by the solid-state welding process, friction stir welding (FSW), which has recently become very important in aluminum and alloy welding. For welding AA2024-T35 with MIG and TIG fusion processes, the filler material ER 4043—AlSi₅ was chosen because of reduced cracking. Different methods were used to evaluate the quality of the produced joints, including macro- and microstructure evaluation, in addition to hardness and tensile tests. The ultimate tensile strength (UTS) of the FSW sample was found to be 80% higher than that of MIG and TIG samples. The average hardness value of the weld zone of metal for the MIG- and TIG-produced AA2024-T3511 butt joints showed a significant decrease compared to the hardness of the base metal AA2024-T351 by 50%, while for FSW joints, in the nugget zone, the hardness is about 10% lower relative to the base metal AA2024-T3511. Full article

New and innovative technologies have expanded the quality and applications of aluminum welding in the maritime, aerospace, and automotive industries. One such technology is the addition of nanoparticles to aluminum matrices, resulting in improved strength, operating temperature, and stiffness. Furthermore, researchers continue to assess pertinent factors that improve the microstructure and mechanical characteristics of aluminum welding by enabling the optimization of the manufacturing process. Hence, this research explores alternatives, namely cost-effective aluminum welding fillers reinforced with niobium diboride nanoparticles. The goal has been to improve weld quality by employing multi-objective optimization, attained through a central composite design with a response surface model. The model considered three factors: the amount (weight percent) of nanoparticles, melt stirring speed, and melt stirring time. Filler hardness and porosity percentage served as response variables. The optimal parameters for manufacturing this novel filler for the processing conditions studied are 2% nanoparticles present in a melt stirred at 750 rpm for 35.2 s. The resulting filler possessed a 687.4 MPA Brinell hardness and low porosity, i.e., 3.9%. Overall, the results prove that the proposed experimental design successfully identified the optimal processing factors for manufacturing novel nanoparticle-reinforced fillers with improved mechanical properties for potential innovative applications across diverse industries. Full article

The prerequisite of the weld bead finishing is intricately linked to the quality of the welded joint. It constitutes the final, yet pivotal, stage in its formation, significantly influencing the reliability of structural components and machines. This article delineates an innovative post-weld surface finishing method, distinguished by the movement of a specialized cutting tool along a butt weld. This method stands out due to its singular approach to machining allowance, wherein the weld bead height is considered and eradicated in a single pass of the cutting tool. Test samples were made of AISI 304L, AISI 316L stainless steels and EN AW-5058 H321, EN AW-7075 T651 aluminum alloys butt-welded with TIG methods. Following the welding process, the weld bead was finished in accordance with the innovative method to flush the bead and the base metal’s surface. For the quality control of welded joints before and after the weld finishing, two non-destructive testing methods were chosen: Penetrant Testing (PT) and Radiographic Testing (RT). This article provides results from the examination of 2D profile parameters and 3D stereometric characteristics of surface roughness using the optical method. Additionally, metallographic results are presented to assess changes in the microstructure, the microhardness, and the degree of hardening within the surface layer induced by the application of the innovative post-weld finishing method. Full article

This study investigates the new surface development on AA6061 and AA5086 alloys considering the wire-arc additive manufacturing technique as a direct energy deposition (DED) process of wire. Two different quantities of MWCNTs, i.e., 0.01 (low) and 0.02 (high) g, with a constant nickel (Ni) weight (0.2 g) were pre-placed in the created square patterns. ER4043 filler was used as a wire for additive deposition, and an arc was generated through a tungsten inert gas (TIG) welding source. Furthermore, hardness and pin-on-disk wear-testing methods were employed to measure the changes at the surfaces with the abovementioned inducements. This work was designed to illustrate the hardness and the offered wear resistance in terms of mass loss of the AA6061 and AA5086 aluminum alloys with the function of nano-inducements. Two sliding distance values of 500 m and 600 m were selected for the wear analysis of mass loss from tracks. A maximum increase in hardness for AA6061 and AA5086 alloys was observed in the experiments, with average values of 70.76 HRB and 74.86 HRB, respectively, at a high mass content of MWCNTs. Moreover, the tribological performance of the modified surfaces improved with the addition of MWCNTs with Ni particles in a broader sense; the modified surfaces performed exceptionally well for AA5086 compared to AA6061 with 0.02 and 0.01 g additions, respectively. The system reported a maximum of 38.46% improvement in mass loss for the AA5086 alloy with 0.02 g of MWCNTs. Moreover, the morphological analysis of the developed wear tracks and the mechanism involved was carried out using scanning electron microscope (SEM) images. Full article

In order to address the irregularity of the welding path in aluminum alloy frame joints, this study conducted a numerical simulation of free-path welding. It focuses on the application of the TIG (tungsten inert gas) welding process in aluminum alloy welding, specifically at the intersecting line nodes of welded bicycle frames. The welding simulation was performed on a 6061-T6 aluminum alloy frame. Using a custom heat source subroutine written in Fortran language and integrated into the ABAQUS environment, a detailed numerical simulation study was conducted. The distribution of key fields during the welding process, such as temperature, equivalent stress, and post-weld deformation, were carefully analyzed. Building upon this analysis, the thin-walled TIG welding process was optimized using the response surface method, resulting in the identification of the best welding parameters: a welding current of 240 A, a welding voltage of 20 V, and a welding speed of 11 mm/s. These optimal parameters were successfully implemented in actual welding production, yielding excellent welding results in terms of forming quality. Through experimentation, it was confirmed that the welded parts were completely formed under the optimized process parameters and met the required product standards. Consequently, this research provides valuable theoretical and technical guidance for aluminum alloy bicycle frame welding. Full article

This paper presents the effect of burnishing on the surface hardness, selected surface roughness parameters and material ratio of tubes made of an EN AW-6060 aluminum alloy after welding. The prepared specimens were subjected to a 141-TIG welding process, after which the surfaces to be burnished were given a finishing turning treatment with DURACARB’s CCGT09T302-DL cutting insert to remove the weld face. After the turning process, the surface finish treatment was carried out by rolling burnishing, for which Yamato’s SRMD burnishing tool was used. The surface hardness, selected surface roughness parameters and material ratio were then measured. An analysis of the results showed an increase in hardness in the surface layer, as well as an improvement in the analyzed surface roughness parameters and the material ratio of the native material and the weld. Full article

In this study, 7075 aluminum alloy welding wire with TiB₂ nanoparticle reinforcement as an additive together with the variable polarity TIG welding arc as a heat source were applied to produce thin-walled deposited layer samples. Results indicated that the performance of the deposited structure of 7075 aluminum alloy with a TiB₂ reinforcement phase was significantly improved compared to the deposited structure of ordinary 7075 aluminum alloy welding wire. Meanwhile, the precipitation of the TiB₂ reinforcement phase was insufficient within the structure, and the enhancing effect could not be fully exerted. Moreover, the 7-series aluminum alloy contained a large amount of Zn and Mg elements inside. If the soluble crystalline phase was not fully dissolved, severe stress corrosion could be caused, which inevitably led to a decrease in the mechanical properties. To further improve the performance of the deposited layer, a T6 heat treatment process was performed at 470 °C for 2 h, followed by rapid cooling with distilled water and artificial aging at 120 °C for 24 h. After heat treatment, many second phases appeared in the microstructure of the deposited layer, and the tensile strength increased from (361.8 ± 4.8) MPa to (510.2 ± 5.4) MPa together with the elongation which increased from (9.5 ± 0.5) % to (10.2 ± 0.4) %. The fracture mode of the fracture was a ductile fracture along grain boundaries. The microhardness increased from (145 ± 5) HV to (190 ± 4) HV and exhibited good corrosion resistance in a 3.5% NaCl solution corrosion test. Full article

This study investigated the use of the linear regression algorithm (LRA) for estimating the cost of tungsten inert gas (TIG) welding of dissimilar metals, specifically, stainless steel 304 and aluminum 2024. Various cost analysis parameters, including weld time, power cost rate, labor cost, filler rod cost, and shielding gas cost, were considered. LRA was employed to develop a predictive model for welding costs based on these parameters. The model was then used to optimize welding parameters by identifying the combination that minimized overall welding costs. The results demonstrate that LRA effectively identified a more cost-effective parameter set compared to traditional methods. This highlights the potential of LRA in enhancing the cost-effectiveness of TIG welding processes. The findings have practical implications for field engineers and researchers, enabling the identification of optimal parameters for cost estimation and significant cost savings. Full article

Large residual stress of 2219 aluminum alloy induced by Tungsten Inert Gas (TIG) welding decreases its service performances. Shot peening was adopted to decrease the residual stress of TIG welding. Numerical models of TIG welding and shot peening were established using the combined discrete and finite element methods (DEM–FEM). The results show that TIG welding induces tensile residual stress due to the heat exchange effect and the longitudinal stress is larger than that in the transverse direction. The maximum tensile stress occurs at a depth of 0.1 mm. The surface tensile stress changes to compressive stress after shot peening as the severe deformation induced by the shots changes the stress state of the plate. The maximum value of compressive stress (σm) and the peened depth with compressive stress (Z0) are adopted to describe the peening effect. The absolute value of σm increases with the increased peening speed and nozzle height. Mixed shots with a diameter of 0.8 mm and 1.2 mm induce larger value of σm than those with only a diameter of 1.2 mm. The value of Z0 increases with the ascending shots diameter and nozzle height, while it varies nonmonotonically with the peening speed. The effect of shot peening on the residual stress in TIG welding is discussed. Full article

Selecting an economically suitable welding technique and optimizing welding parameters to obtain high joint quality is considered a challenge for expanding the 5xxx aluminum alloy series in various industrial applications. This work aims to investigate the effect of applying different welding techniques, tungsten inert gas (TIG) and metal inert gas (MIG), as fusion welding processes compared to friction stir welding (FSW), a solid-state joining process, on the joint performance of the produced 5 mm thick similar AA5083-H111 butt weldments at different welding conditions. Different methods were used to evaluate the quality of the produced joints, including visual inspection, radiographic testing (RT), and macrostructure evaluation, in addition to hardness and tensile tests. The fracture surface of the tensile-failed specimens was also investigated using a scanning electron microscope (SEM). Furthermore, the current study ended with an economic analysis of the welding techniques used. The results showed that, for the friction stir-welded joints, the radiographic films revealed defect-free joints at the two applied travel speeds of 100 mm/min and 400 mm/min and a constant tool rotating speed of 400 rpm. In addition, only one joint was welded by MIG at a welding current of 130 Amp, with a 19 L/min flow rate of pure argon. In contrast, the radiographic films showed internal defects such as lack of fusion (LOF), lack of penetration (LOP), and porosity (P) for the two joints welded by TIG and one joint welded by MIG. The hardness of the welded joints was enhanced over the AA5083-H111 base material (BM) by 24–29, 31–35, and 46–50% for the MIG, TIG, and FSW joints, respectively. The maximum ultimate tensile strength was obtained for the FSW joint welded at a 400 mm/min travel speed. Adopting FSW in shipbuilding applications can further produce the AA5083-H11 joints with higher quality and efficiency than fusion welding techniques such as MIG and TIG processes. In addition, time and cost comparisons between TIG, MIG, and FSW were performed for five-millimeter-thick and one-meter-long AA5083-H111. Full article

As a highly effective welding method, PPCA-TIG (Powder Pool Coupled Activating Flux–Tungsten Inert Gas) welding aims to achieve automated activation of TIG welding through the use of suitable activating fluxes. However, due to the unique transitional behavior of activating elements, the mechanism of PPCA-TIG is a little bit different from common activating TIG welding. In this research, a two-dimensional model is established to investigate the effect of four activating fluxes (TiO₂, SiO₂, MnO₂, CaF₂) on arc morphology and force. A series of welding experiments is performed to study the impact of the different activating elements on the molten pool. The results show that the increase in the penetration of TiO₂ is related to the high arc temperature and great arc force and electromagnetic force in the molten pool. The problem of the softening of 3003 aluminum alloy welded joints is solved. Other activating fluxes are less effective than TiO₂. The addition of calcium fluoride significantly affects penetration. The use of TiO₂, SiO₂ and MnO₂ changes the molten pool viscosity and affects the molten pool oscillation, thus affecting the weld quality. Full article

TIG arc additive manufacturing experiments were performed utilizing TiB₂ nanoparticle-reinforced toward to 7075 aluminum alloy welding wire, and the microstructure and mechanical properties corresponding to different locations of welding plate were investigated. At the top location of the deposited layer, the microstructure was characterized by fine dendrite induced by solidification, and equiaxed grain was predominant at the middle location. The grain size at the bottom location was obviously larger compared to the top and middle locations, and secondary-phase particles were homogeneously distributed at the grain boundary or inner grains. The mechanical properties at the top location of the deposited layer were most excellent compared to the middle and bottom locations, and the tensile properties and micro-hardness were decreased with the detected area varying from middle location to the bottom location. The excellent combination of fracture elongation and maximum of tensile strength corresponding to different locations on the deposited layer were determined to be 361.8 MPa with respect to the 7075 aluminum alloy welding wire, respectively, which was higher compared to the samples processed by general arc additive manufacturing process with tensile strength of (279.4 ± 5.3) MPa, indicating the TiB₂ nano-sized particles possessed certain enhancing effects on the investigated 7075 aluminum alloy. Full article

An aluminum 6061 (Al6061) metal matrix composite (MMC) reinforced with silicon carbide was prepared by stir casting. Specimens of the required dimensions were welded using the tungsten inert gas (TIG) method. ER5356 (Al-5%Mg) was chosen as the appropriate filler material for TIG welding. The input current parameter was varied (150, 170 and 200nA) while maintaining the other welding parameters at constant values. An assessment of the mechanical (tensile and impact strength) and microstructure properties of the TIG-welded Al6061 MMC with 6 wt. % silicon carbide particles was accomplished. An 8.27% improvement was observed in ultimate tensile strength (UTS) for the 150 A TIG-welded sample. UTS and elasticity decreased linearly with an increase in welding current but exhibited higher values than in non-welded specimens. The microstructural analysis of the welded MMCs showed a mixed mode of failure, with equiaxial dimples being dominant in lower-weld-current specimens. Compared to non-welded specimens, a 40% increase in impact strength was observed for the 150 A TIG-welded specimens, which decreased with an increase in the welding current value. SEM analysis revealed ductile striations and continuous river patterns, resulting in mixed failure. Full article