Shuhang Zhang , Xin Jin , Zhijiang Lou , Sen Wang , Shan Lu , Yifan He
{"title":"LSDF-Net: An efficient lightweight defect detection method for ultrasonic welding surfaces","authors":"Shuhang Zhang , Xin Jin , Zhijiang Lou , Sen Wang , Shan Lu , Yifan He","doi":"10.1016/j.jajp.2025.100339","DOIUrl":"10.1016/j.jajp.2025.100339","url":null,"abstract":"<div><div>This paper proposes LSDF-Net, a lightweight and high-speed detection network designed to address the challenges of insufficient accuracy and high computational cost in ultrasonic welding surface defect detection. Built upon the YOLOv8 architecture, LSDF-Net integrates a Dynamic Surface Detail Fusion Module (DSDFM) to enhance multi-scale feature representation and introduces a Lightweight Shared Convolution and Separate Batch Normalization detection head (LSCSBD) to reduce parameters and accelerate inference. In addition, a LAMP-based pruning strategy is applied, which achieves a 67% reduction in model size and a 48% reduction in computational cost with almost no performance degradation. Experimental results on both a self-constructed ultrasonic welding defect dataset and the public NEU-DET dataset demonstrate that LSDF-Net achieves the best overall performance, striking an excellent balance between accuracy and real-time inference. These results highlight its strong potential for real-time industrial defect detection applications.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100339"},"PeriodicalIF":4.0,"publicationDate":"2025-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144925754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fadi Al-Badour , Ahmad H. Bawagnih , Ahmed Ali , Rami K. Suleiman , Necar Merah
{"title":"Surface cracks repair in AA6061-T6 aluminum alloys using friction stir processing","authors":"Fadi Al-Badour , Ahmad H. Bawagnih , Ahmed Ali , Rami K. Suleiman , Necar Merah","doi":"10.1016/j.jajp.2025.100340","DOIUrl":"10.1016/j.jajp.2025.100340","url":null,"abstract":"<div><div>Friction Stir Welding (FSW) is an advanced solid-state joining technique that offers an effective solution for repairing surface cracks in aluminum alloys. This study investigates the repair of an artificially induced 2 mm square groove in AA6061-T6 aluminum alloy plate; resemble pre-repair preparation, using friction stir processing (FSP), incorporating an aluminum filler rod and silicon carbide (SiC) nanoparticles as a reinforcement to ensure complete crack sealing. FSP was conducted on both cracked and crack-free samples, with a focus on the impact of tool offset during the repair process. Tool offsets of 0 mm, 1.75 mm, and 3.5 mm were employed toward the advancing side to assess their influence on the repair process. Mechanical testing, microstructural characterization, temperature, and force analysis were performed to comprehensively evaluate the repair strategy. The repaired samples exhibited an average ultimate tensile strength (UTS) of approximately 180 MPa, closely matching the 186 MPa observed in crack-free bead-on-plate welds. Additionally, the microhardness at stir zone (SZ) improved to average values of 77 HV for 0 mm offset and 80 HV for 1.75 mm offset, compared to 70 HV in the bead-on-plate welds . Despite the presence of microstructural defects, the use of tool offset contributed to satisfactory mechanical performance. However, samples welded with 0 mm tool offset exhibited slightly superior mechanical properties. Overall, this research highlights the feasibility of using FSP, combined with SiC nanoparticles reinforced filler material and tool offset control, as a promising approach for effective surface crack repair in aluminum alloys, providing a foundation for further process optimization and industrial application.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100340"},"PeriodicalIF":4.0,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144841611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Christian Frey , Mikail Kacar , Arda Hiz , Robert Gerlach , Willem Leterme , Simon Olschok
{"title":"Analyzing the utilization of high-voltage electric fields for laser material processing","authors":"Christian Frey , Mikail Kacar , Arda Hiz , Robert Gerlach , Willem Leterme , Simon Olschok","doi":"10.1016/j.jajp.2025.100341","DOIUrl":"10.1016/j.jajp.2025.100341","url":null,"abstract":"<div><div>Laser material processing has become an essential technique in industrial manufacturing in form of welding, drilling, cutting and structuring. However, process emissions such as the metal vapor plume pose a challenge, as they can impair the efficiency and precision of the laser process through reflection, absorption, and scattering. Conventional methods attempt to reduce the influence of the metal vapor plume by using shielding gases to remove the particles from the laser beam path. A novel alternative is the use of electric fields for targeted manipulation of the metal vapor to control the extinction effects. High voltage capacitors can precisely control the electric field which offers greater adaptability to a dynamic laser process. The following study investigates the utilization of high voltage capacitor configurations for generating electric fields to actively deflect metal vapor from the laser beam path during laser welding. The distribution of the electric field is analyzed using the finite element method (FEM) for the considered capacitor geometries. The weld seam geometry shows a distinct geometry depending on the selected capacitor arrangement, and the weld penetration depth decreases with the use of the electric field. The measurable trend remains preliminary, since it is assumed that the welding fume is held over the welding position by the electric field, which influences the result.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100341"},"PeriodicalIF":4.0,"publicationDate":"2025-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144829242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measurement of residual stress due to deformation caused by slight hydroforming deformation process in double-walled pipes through external pressure","authors":"Reza Mansourian, Masoud Mahmoodi","doi":"10.1016/j.jajp.2025.100338","DOIUrl":"10.1016/j.jajp.2025.100338","url":null,"abstract":"<div><div>In this study, the measurement of residual stress due to deformation caused by slight hydroforming deformation process in double-walled pipes through external pressure was studied. Residual stresses were measured by nanoindentation of ST52 steel/GGG70 iron double-walled pipes. The results showed that the highest compressive residual stress was created on the inner surface of the GGG70 with effective parameters of pressure of 146 tons, the temperature of 73 °C, and percentage of Al₂O₃ nanoparticles powder in fluid of 5.6 %. Repeated nanoindentation measurements on the reference (stress-free) sample showed a variation of approximately 10 %, indicating acceptable repeatability of the method. The stresses are almost uniform and the same along the length of the part, and only very slight changes are observed in the part's initial part. The stress in the outer wall is obtained at the outer surface of ∼ 502.6 MPa and the inner surface of 506.6 MPa. Considering that the yield stress of the outer wall is considered to be ∼ 500 MPa, the entire outer wall is in a plastic state but has undergone a good amount of plastic deformation. Residual stresses are initially tensile and then reach their maximum value and with increasing depth, they are converted into compressive residual stresses and then reach an equilibrium state in the base metal. With increasing depth, there is not much change in the maximum tensile residual stress.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100338"},"PeriodicalIF":4.0,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144829241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparative study of inertia and continuous drive friction welding processes based on equivalent energy input","authors":"Carina Vauderwange , Dirk Lindenau , Heinz Palkowski , Hadi Mozaffari Jovein","doi":"10.1016/j.jajp.2025.100337","DOIUrl":"10.1016/j.jajp.2025.100337","url":null,"abstract":"<div><div>Rotary friction welding can be performed using either continuous drive friction welding (CDFW) or inertia friction welding (IFW), which utilizes stored energy in a flywheel. Historically, these methods have distinct applications and geographic preferences: IFW is prevalent in the US, especially for superalloys, while CDFW is more common in Europe, focusing on automotive materials like steel and aluminum. This study presents a comparative analysis of both welding techniques using the same friction welding machine to minimize external variables. The free-machining steel AISI 1215, chosen for its banded microstructure, serves as the specimen material. The comparison is based on the same energetic input of 82.8 kJ to ensure consistency. However, IFW experienced significant losses due to internal friction, which further decelerated the spindle and reduced the effective weld energy to 68 kJ. Key findings include differences in deformation behavior and weld formation efficiency. CDFW exhibits a softer deformation, with principal shortening occurring during the forge phase due to axial force, resulting in large equiaxed inclusions in the weld zone. Additionally, less upset is generated with the same calculated energy input. In contrast, IFW demonstrates sharper deformation, with main shortening in the friction phase, achieving greater total upset. The combination of axial force and torque produces a spiralized material flow and finely dispersed inclusions due to high shear forces. These insights highlight the distinct advantages and characteristics of each welding technique, providing valuable information for their respective applications.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100337"},"PeriodicalIF":4.0,"publicationDate":"2025-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Yarmou shamsabadi , M. Farvizi , L. Nikzad , A. Malekan
{"title":"Dissimilar TLP bonding of X-45/Hastelloy X superalloys using BNi-2 filler metal: Microstructural evolution and mechanical behaviors","authors":"A. Yarmou shamsabadi , M. Farvizi , L. Nikzad , A. Malekan","doi":"10.1016/j.jajp.2025.100335","DOIUrl":"10.1016/j.jajp.2025.100335","url":null,"abstract":"<div><div>This article explores the dissimilar joining of two commonly utilized superalloys, X-45 and Hastelloy X (HX), through the Transient Liquid Phase (TLP) bonding technique using BNi-2 filler metal. The TLP process was performed at 1050 °C for varying durations (5–60 min). Microstructural analyses indicated that longer holding times at 1050 °C alongside the diffusion of Melting Point Depressant (MPD) elements into the base materials led to the completion of isothermal solidification and the elimination of the eutectic structure from the Athermally Solidified Zone (ASZ). The MPD elements exhibited varying diffusion rates across the joint's two sides. Increased diffusion of elements on the Hastelloy X side resulted in denser and more widespread precipitates than on the opposite side of the joint, although this region produced harder precipitates. To analyze the connection between microstructure and mechanical properties, a combination of microhardness and shear testing was utilized. Shear tests revealed two distinct types of fractures for joints formed over different durations: one type occurred when isothermal solidification was not completed, resulting in a cleavage fracture with low shear strength and weak bonding due to brittle eutectic compounds in the ASZ, while the other happened when isothermal solidification was complete, showing ductile fracture from the Diffusion Affected Zone (DAZ) that had the highest hardness following ASZ removal. The increased density of precipitates and broader precipitation zone on the HX side promote crack propagation along the boride-rich grain boundaries in this region, ultimately leading to the final fracture.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100335"},"PeriodicalIF":4.0,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144757819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laura de Lima e Silva , Nadège Ducommun , Laurent Jubin , Ronan Mainguy , Jérôme Esvan , Eric Andrieu , Christine Blanc
{"title":"Effect of the thermal oxide on the stress corrosion cracking susceptibility of stainless steels welds in chloride-containing media","authors":"Laura de Lima e Silva , Nadège Ducommun , Laurent Jubin , Ronan Mainguy , Jérôme Esvan , Eric Andrieu , Christine Blanc","doi":"10.1016/j.jajp.2025.100334","DOIUrl":"10.1016/j.jajp.2025.100334","url":null,"abstract":"<div><div>The stress corrosion cracking (SCC) susceptibility of a non-polished 316 L austenitic stainless steel (ASS) welded joint, <em>i.e</em>., covered by a thermal oxide film, was studied by carrying out uniaxial tensile tests in a 1 M NaCl solution (pH 4, 60 °C). Experiments were also performed on a polished weld, <em>i.e.</em>, covered by a native oxide film, for comparison. The thermal oxide film presented a bi-layer structure similar to that of the native oxide film, but the ratio Fe/Cr in the outer layer of the thermal oxide film was higher. Moreover, the thermal oxide film was thicker than the native oxide film, but it was more porous and showed a gradient in chemical composition and morphology as a function of the distance from the fusion line of the weld. The defective structure of the thermal oxide film was associated with a degradation in the corrosion behaviour of the non-polished weld, as well a change in the crack propagation mode during SCC tests, from intergranular to transgranular even though the cracks formed preferentially in the heat affected zone (HAZ) for both polished and non-polished samples. Furthermore, crack propagation was promoted, with cracks extending across multiple grains, in the HAZ of the non-polished sample near the fusion line, where the thermal oxide was more porous and richer in Fe compared to the HAZ far from the fusion line. The results therefore highlighted the major influence of the thermal oxide properties on the corrosion behaviour and SCC susceptibility of the 316 L weld.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100334"},"PeriodicalIF":4.0,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alex Jordan , Lucas Hermelingmeier , Julian Gilich , Gerson Meschut , Marco De Santis , Alexander Schlüter
{"title":"Comparison of the economic efficiency and sustainability of two debonding processes for structurally bonded sills","authors":"Alex Jordan , Lucas Hermelingmeier , Julian Gilich , Gerson Meschut , Marco De Santis , Alexander Schlüter","doi":"10.1016/j.jajp.2025.100332","DOIUrl":"10.1016/j.jajp.2025.100332","url":null,"abstract":"<div><div>In light of growing demands for resource efficiency and sustainability in vehicle engineering, the environmentally compatible separation of structural adhesive joints is gaining increasing relevance. This study presents a comparative analysis of two physically based debonding methods: the established hot-air process and a cryogenic cold process based on liquid nitrogen (LN<sub>2</sub>). The primary objective is to assess the ecological impact and process-related sustainability of both approaches.</div><div>Experimental investigations were conducted on a component-representative triple-sheet structure that simulates common automotive flange joints. Thermal input was applied either by convective heating using a hot air gun or by direct cooling through a contact-based LN<sub>2</sub> tool. The resulting temperature profiles were recorded using spatially distributed thermocouples. Subsequently, the outer panel was selectively debonded to replicate a repair scenario, and the mechanical integrity of the remaining adhesive joint was evaluated through Mode I testing of l-shaped specimens. Process data served as input for an Life Cycle Assessment (LCA) according to DIN EN ISO 14,040.</div><div>The cryogenic method achieved a 40 % reduction in carbon footprint compared to the hot-air process (0.337 kg vs. 0.559 kg CO<sub>2</sub>-equivalents), primarily due to its shorter process time and more efficient heat transfer. While the hot-air method’s impact is mainly driven by electrical energy use, that of the cold method stems from cryogenic media consumption. Notwithstanding certain disadvantages in specific impact categories, the LN<sub>2</sub>-based process exhibits a superior overall ecological performance and signifies a promising solution for repair- and recycling-oriented adhesive separation in structural vehicle applications.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100332"},"PeriodicalIF":4.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144750366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The effect of heat input on the residual stress distribution in gas-metal arc welding of carbon steel: Simulation and experimental methods","authors":"Amir Dadkhah , Mahmoud Sarkari Khorrami , Seyed Farshid Kashani-Bozorg , Reza Miresmaeili","doi":"10.1016/j.jajp.2025.100333","DOIUrl":"10.1016/j.jajp.2025.100333","url":null,"abstract":"<div><div>A major challenge in fusion welding is the development of residual stresses and distortions, stemming primarily from non-uniform thermal cycles during welding. These stresses adversely influence fatigue life, corrosion resistance, and dimensional stability of engineering components. Heat input is a crucial parameter governing residual stress formation. Conventional experimental methods for residual stress determination are often time-consuming or destructive, making simulation an efficient alternative for stress prediction. This study assessed the effect of heat input on residual stress in the gas metal arc welding (GMAW) process through integrated simulation and hole-drilling measurements. For this purpose, A516 Gr70 steel plates were welded using the GMAW technique with varying heat inputs, both with and without a back welding. After characterizing microstructure and mechanical properties, residual stresses were quantified via the hole-drilling method. Numerical simulation employed Abaqus with the Goldak double-ellipsoid heat source model and element birth-and-death technique, with results validated against experimental data. The microhardness value of the weld zone produced by the lowest heat input was found to be ∼198 HV, with a microstructure dominated by pearlite and varying morphologies of ferrites. Simulation revealed peak residual stresses in the heat-affected zone (HAZ) and weld center across all heat inputs. The reduction in heat input and applying the back welding resulted in less tensile residual stresses in most areas and slightly increased compressive residual stresses in areas farther from the HAZ. Four-channel thermocouple measurements and numerical simulation provided detailed thermal analysis during welding, with simulated residual stresses showing 96 % agreement with hole-drilling results, validating both methodologies.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100333"},"PeriodicalIF":4.0,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144723658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Furkan Khan, Takuya Miura, Yoshiaki Morisada, Kohsaku Ushioda, Hidetoshi Fujii
{"title":"Process parameter optimization and bonding mechanism in dissimilar S45C/A6061 joints via novel sacrificing-sheet linear friction welding","authors":"Furkan Khan, Takuya Miura, Yoshiaki Morisada, Kohsaku Ushioda, Hidetoshi Fujii","doi":"10.1016/j.jajp.2025.100331","DOIUrl":"10.1016/j.jajp.2025.100331","url":null,"abstract":"<div><div>Sacrificing-sheet linear friction welding (SSLFW) is a novel solid-state joining technique developed to address the challenges of dissimilar welding between S45C steel and A6061 aluminum alloy, which are difficult to join using conventional linear friction welding (LFW). In this method, a S45C center sheet is linearly oscillated while the two base materials, i.e., S45C and A6061, are pressed against it using a center-driven double-sided LFW machine. The center sheet acts as a sacrificial sheet, which is progressively expelled from the joint interface during welding owing to thermomechanical effect from each side, thereby enabling direct joining between the base materials. This study investigates the effects of key process parameters on mechanical properties and interfacial microstructure, and clarifies the bonding mechanism of SSLFW. Optimum welding conditions with 2 mm upset length, 300 MPa applied pressure toward A6061, 1 s preheat time, and 50 MPa preheat pressure produced sound, defect-free joints with a thin, continuous intermetallic compound (IMC) layer of approximately 100 nm. These conditions enabled simultaneous plastic deformation of both base materials through sacrificing role of center sheet and effective suppression of unbonded regions. The resulting as-welded joint achieved a peak tensile strength of ∼235.3 MPa, corresponding to a joint efficiency of ∼73 % with respect to the A6061 base metal. Post-weld artificial aging significantly exhibited hardness recovery on the A6061 side, enhancing the joint strength to ∼307 MPa and increasing joint efficiency to ∼96 %. These results demonstrate the high potential of SSLFW for sound dissimilar metal joining.</div></div>","PeriodicalId":34313,"journal":{"name":"Journal of Advanced Joining Processes","volume":"12 ","pages":"Article 100331"},"PeriodicalIF":3.8,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}