Welding in the World最新文献

{"title":"Comparison of different fatigue assessment methods for HFMI-treated longitudinal stiffeners under variable amplitude loading","authors":"L. Wendler,&nbsp;T. Nitschke-Pagel,&nbsp;I. Engelhardt","doi":"10.1007/s40194-026-02427-w","DOIUrl":"10.1007/s40194-026-02427-w","url":null,"abstract":"<div><p>Due to the extensive research on High-Frequency Mechanical Impact (HFMI) treatment in recent years, regulations regarding HFMI treatment are increasingly being incorporated in the revision of design codes and recommendations. Generally, these trends promise a greater application of HFMI treatment in practice and therefore offer the potential of realising resource-efficient and durable lightweight constructions. However, the increasing number of guidelines is also accompanied by some differences regarding the assessment methods and the evaluation of the fatigue life of HFMI treated welds which may lead to divergent estimations of fatigue life. Therefore, this study analyses differences between the assessment methods, provided by current and upcoming design codes and recommendations for HFMI treated welds, specifically in terms of nominal and effective notch stress approach. Overall, the results indicate that current design rules lead to a conservative fatigue assessment, implying that the potential of an increased fatigue strength cannot be fully considered within the fatigue life estimation. This study primarily focuses on options of taking different R-ratios into account, as well as the impact of the intersection point of AW and HFMI S–N curve emphasising the assessment of variable amplitude loading. It is observed that particularly at R = − 1 the fatigue assessment tends to be overly conservative due to the inability to account for this effect. Additionally, the results suggest that neglecting the intersection point between AW and HFMI S–N curve may result in an even more conservative fatigue assessment, especially at higher stress ranges. The comparison of different fatigue assessment methods within this study focuses on current IIW-recommendations as well as the upcoming revised version of Eurocode. Applying different assessment methods reveals no significant differences in fatigue estimation, as conservative results were obtained for both guidelines considered in this study. The comparison is carried out based on fatigue test data on the example of the structural detail “longitudinal stiffener” under variable amplitude loading.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"2037 - 2060"},"PeriodicalIF":2.5,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02427-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-proportional fatigue stress criteria in welded joints: a design code perspective","authors":"N. B. Winther,&nbsp;N. M. Bauer,&nbsp;M. Faß,&nbsp;J. Baumgartner,&nbsp;J. H. Andreasen,&nbsp;J. Schjødt-Thomsen","doi":"10.1007/s40194-026-02378-2","DOIUrl":"10.1007/s40194-026-02378-2","url":null,"abstract":"<div><p>Welded joints often exhibit a significant reduction in fatigue life when subjected to non-proportional (NP) multiaxial loading conditions. Therefore, it is essential to evaluate how current design codes account for NP fatigue and whether their assessment criteria remain adequate. This study examines five NP fatigue life assessment methods from major design codes: IIW [1], DNV [2], ASME [3], FKM [4] and BSI [5] using a database of 22 experimental studies involving NP fatigue in welded steel joints. The evaluation is based on two structural stress assessment approaches derived from finite element analysis: the fine hotspot stress method, as recommended by IIW, DNV, FKM, and BSI, and the equivalent(-equilibrium) structural stress method (E(E)SS) method as proposed by ASME. These are also compared to two benchmark nominal stress-based criteria: maximum principal stress and von Mises stress. The results confirm that NP stress states lead to a notable reduction in fatigue life. While none of the evaluated design codes completely correct for this effect, the IIW and ASME method perform best overall in terms of prediction accuracy and consistency. Furthermore, the study proposes calibrated NP correction factors for each method based on the database. These factors yield near-perfect alignment between predicted and experimental fatigue life, offering a potential basis for improving current design practices.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"1949 - 1970"},"PeriodicalIF":2.5,"publicationDate":"2026-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02378-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of build-up height on residual stresses in additive repair and modification using DED-Arc with high-strength filler metals","authors":"R. Scharf-Wildenhain,&nbsp;L. Engelking,&nbsp;A. Haelsig,&nbsp;D. Schroepfer,&nbsp;T. Kannengiesser,&nbsp;J. Hensel","doi":"10.1007/s40194-026-02417-y","DOIUrl":"10.1007/s40194-026-02417-y","url":null,"abstract":"<div><p>Directed energy deposition (DED)-Arc is suitable for the hybrid additive manufacturing, modification and repair of large metal components with high deposition rates. Residual stresses and distortion are of central importance when characterizing the manufactured components and the sensitive transition area between additive manufactured (AM) component and semi-finished product. Residual stresses caused by the thermal cycles during the manufacturing process can impair the mechanical properties of the manufactured parts and can lead to component failure, especially for high-strength steels. Therefore, understanding and controlling residual stresses, when combining different base and feedstock materials, is critical to improve the quality and efficiency of the hybrid DED-Arc process. This article deals with the influence of the build-up height on the residual stress distribution of additively manufactured components with a selected base and feedstock material from commercial high-strength steels. Using a robot-assisted DED-system and a controlled short arc, AM welding experiments were carried out with close to the application parameters at working temperature (200 °C) and heat input (650 kJ/m). Five hybrid AM specimens (AM wall on upright structural steel plate) were produced using a one bead per layer strategy and selected AM-wall heights between 15 and 300 mm. The influence of the AM build height on the longitudinal residual stress in the whole hybrid AM specimen (in welding direction) was analyzed and discussed. All experiments exhibit comparable stress distributions in the area of the substrate plate up to the heat-affected zone (HAZ) and the transition zone, regardless of the building height. The height significantly influences the residual stress distribution of the deposited AM-component. Tensile residual stresses with a maximum range between 300and 400 MPa were always found in the last approx. 18 component layers (upper 40 mm). This is due to restraint of the shrinking of the top layers by the layers below. The lower layers show homogeneous residual stress distributions characterized by low compressive stresses due to the process-related tempering during the deposition of each layer on top of each other. As a result, the significant difference between the various AM build-up heights of the hybrid AM specimens is the extent (or height) of this tempered zone with low compressive stresses. These correlations contribute to the understanding of residual stress development with increasing structure height or ratio of component heights of substrate semi-finished product and AM component in hybrid additive manufacturing.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"2025 - 2036"},"PeriodicalIF":2.5,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02417-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of mean stress on the fatigue of welded tubular structures under uniaxial fatigue loading","authors":"Maximilian Kling,&nbsp;Matthias Winkler,&nbsp;Sascha Knefelkamp,&nbsp;Andre Dürr,&nbsp;Klemens Rother","doi":"10.1007/s40194-026-02390-6","DOIUrl":"10.1007/s40194-026-02390-6","url":null,"abstract":"<div><p>Welded hollow section joints are essential for weight reduction in load-bearing structures of agricultural machinery and cranes while maintaining high load capacity. In mobile and gantry cranes, their favorable structural properties enhance durability and significantly reduce overall weight, thereby improving maneuverability and energy efficiency. In these applications, primary loads induce cyclic stresses with either tensile or compressive mean components, which interact with residual stresses from the welding process. In the nominal stress approach of existing codes and guidelines, mean stress effects are typically disregarded due to the assumption of high residual tensile stresses. The structural stress method outlined in the CIDECT Design Guide also does not account for residual or mean stresses, nor does it differentiate between material grades. In contrast, the effective notch stress concept considers mean stress effects via enhancement factors but assumes stress ratio independence for non-stress-relieved and complex welded structures. To address these limitations, fatigue tests with wall thicknesses below 10 mm were conducted within the FOSTA P 1603 research project at Munich University of Applied Sciences. The tests focused on X-joints made of rectangular and circular hollow section tubes using S355J2H and high-strength S620QH steels. The joints were tested under up to four different load ratios. The results are evaluated using the nominal stress and local stress fatigue approaches to identify discrepancies in current guidelines and to develop more accurate, less conservative recommendations. This paper presents the experimental findings and highlights the need for improved fatigue assessment methods for welded hollow section joints.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"2005 - 2024"},"PeriodicalIF":2.5,"publicationDate":"2026-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02390-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The full-life corrosion fatigue crack propagation life of 18Ni (250) angled welded joints based on equivalent initial flaw size","authors":"Yongmei Zhu,&nbsp;Mingjiang Fang,&nbsp;Guanjie Xv,&nbsp;Haijun Wang","doi":"10.1007/s40194-026-02389-z","DOIUrl":"10.1007/s40194-026-02389-z","url":null,"abstract":"<div><p>Deep-sea equipment operates in harsh marine environments for extended periods, where the fatigue crack propagation in welded structures under corrosion significantly affects structural safety and service life. Due to the unique nature of corrosion fatigue damage, the process of pit formation, development, and small crack propagation is transferred to long crack life based on the equivalent initial flaw size (EIFS) theory. This work focuses on 18Ni (250) angled welded steel plates to investigate the full-life corrosion fatigue crack propagation life at the weld. Firstly, six 18Ni (250) angled welded joint specimens were prepared, consisting of four normal specimens and two pre-cracked specimens, and then subjected to corrosion fatigue testing. Secondly, the full fatigue life of the specimens was calculated based on experimental data of pre-cracked specimens through a joint simulation of ABAQUS-FRANC3D. A full-life corrosion fatigue crack propagation rate model based on EIFS was established, resulting in the derivation of a corrosion fatigue life prediction formula. Finally, the predicted results were compared with the experimental results to validate the accuracy of the prediction formula. This study provides a reference for fatigue damage prediction and safety operation assessment of deep-sea welded equipment.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"1991 - 2004"},"PeriodicalIF":2.5,"publicationDate":"2026-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beyond data scarcity: achieving cross-wire generalization in single-pass gas metal arc welding through inter-material feature transfer learning","authors":"Wenguang Luo,&nbsp;Yaonan He,&nbsp;Zixuan Wen,&nbsp;Zidong Lin,&nbsp;Xinghua Yu","doi":"10.1007/s40194-026-02354-w","DOIUrl":"10.1007/s40194-026-02354-w","url":null,"abstract":"<div><p>A Random Forest model is developed to predict single-pass GMAW bead width and height from current, voltage, travel speed, derived heat input/polynomial terms, and filler-wire chemistry using a database compiled from published cross-sections. Trained on four steel wires, the model achieves <i>R</i>² = 0.97 for both targets. With only four ER70S-6 samples added, the transferred model reaches <i>R</i>² = 0.98 (width) and 0.96 (height) without degrading accuracy on the original wires; the maximum absolute error is 1.21 mm. Against a Box–Behnken response-surface model built from 17 experiments, the proposed approach delivers comparable or lower errors with far fewer new tests. Interpretability analyses (feature importance, decision paths, PCA/t-SNE, and cosine similarity) highlight heat input as the dominant driver and explain the cross-wire generalization.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 4","pages":"1343 - 1359"},"PeriodicalIF":2.5,"publicationDate":"2026-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of post-weld treatments on fatigue strength of 5083 aluminum transverse attachment joints","authors":"Juho Havia,&nbsp;Kalle Lipiäinen,&nbsp;Antti Ahola,&nbsp;Tuomas Skriko","doi":"10.1007/s40194-026-02383-5","DOIUrl":"10.1007/s40194-026-02383-5","url":null,"abstract":"<div><p>The fatigue of welded joints is a key design criterion in cyclically loaded aluminum structures. Post-weld treatments (PWTs) can be applied to overcome this issue by providing enhanced fatigue capacity in welded joints. Different PWT techniques and design recommendations are well covered for welded steel materials, while welded aluminum joints have received much less attention. This study investigates the applicability and fatigue enhancement of various PWTs in welded 5083-H111 joints in fillet-welded double-sided transverse stiffeners. Constant amplitude loading fatigue tests with the applied stress ratio of <i>R</i> = 0.1 were carried out for post-weld-treated transverse attachment joints. PWTs included residual stress modification techniques, covering high-frequency mechanical impact (HFMI) treatment (with two different process parameters) and shot peening, as well as weld geometry improvement techniques, including weld toe burr grinding and TIG dressing. The fatigue test results were compared to the as-welded reference group. The residual stresses and local weld geometries were measured from specimen series. HFMI treatment with recommended process parameters for steel joints improved fatigue capacity by a factor of 1.3, while lower intensity HFMI treatment provided a significantly higher enhancement with a factor of 2.4. TIG dressing had similar performance to low-intensity HFMI, while shot peening and weld toe burr grinding had slightly poorer performance with improvement factors of 2.2 and 2.0, respectively. The results of this study indicate the high potential of PWTs to enhance the fatigue strength of welded aluminum structures.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"1971 - 1989"},"PeriodicalIF":2.5,"publicationDate":"2026-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02383-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fatigue strength of peened-welded joints after single high compressive load peaks","authors":"Yuki Banno,&nbsp;Koji Kinoshita,&nbsp;Toshiyuki Ishikawa,&nbsp;Kengo Anami","doi":"10.1007/s40194-026-02343-z","DOIUrl":"10.1007/s40194-026-02343-z","url":null,"abstract":"<div><p>This study investigates the fatigue strength of peened-welded joints after single high compressive load peaks. To understand the relaxation behavior of compressive residual stress, out-of-plane gusset welded joints were treated using different peening methods. Compressive residual stress near the peened edge was measured using an X-ray residual stress analyzer while applying plate bending compressive loads. The results showed that compressive residual stresses at 2 mm from the peened edge relaxed proportionally with increasing compressive load. Strain measurements at the same location supported the estimation of stress relaxation behavior. Plate bending fatigue tests were then conducted under a stress ratio of <i>R</i> = 0.5. Fatigue strength decreased with increasing compressive load, and under a 5.8 kN (approximately −286 N/mm²), the fatigue strength approached that of as-weld. Finally, the fatigue results were evaluated using a newly proposed fatigue strength design curve with a cut-off limit for peening treatment, based on recommendations from the JSSC. It was concluded that this curve remains applicable if the applied compressive load after peening does not exceed 3.8 kN. Furthermore, continuous residual stress monitoring at the 2 mm confirmed that fatigue strength improvement remains effective as long as residual compressive stress is preserved during subsequent loading.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"1917 - 1936"},"PeriodicalIF":2.5,"publicationDate":"2026-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interlayer enabled FSW of substantially different AA6061T6 and Ti6Al4V alloys- process optimization, microstructural control, and reliability assessment","authors":"Saed Enam Mustafa,&nbsp;Rajiv Nandan Rai","doi":"10.1007/s40194-025-02322-w","DOIUrl":"10.1007/s40194-025-02322-w","url":null,"abstract":"<div><p>This study investigates friction stir welding (FSW) of substantially different AA6061-T6 and Ti6Al4V alloys using a nickel (Ni) interlayer to enhance weld quality and mechanical performance. A full factorial (2 × 2 × 5) design of experiments was employed to vary tool rotational speed (TRS), welding speed (WS) and tool pin diameter (TPD), and the resulting joints were evaluated by microstructural analysis, microhardness measurements, tensile testing and fracture examination. Among the twenty welding conditions, the parameter combination TRS 500 rpm, WS 14 mm/min and TPD 4.7 mm with Ni interlayer (Sample S9) produced a defect-free weld with homogeneous Al–Ti–Ni mixing, suppressed Al₃Ti formation and a maximum tensile strength of 241 MPa, corresponding to 78% of the AA6061-T6 base-metal UTS. In contrast, a higher-parameter condition (Sample S20: TRS 710 rpm, WS 20 mm/min, TPD 5.5 mm) led to defective joints, with Al₃Ti intermetallic presence and a significantly lower tensile strength of 133 MPa. Microhardness results showed reduced hardness (≈120 HV) at the interface for S9 due to Ni-assisted solid-solution formation and limited Ti fragmentation, whereas S20 and the joint without interlayer (Sample S0) exhibited higher interfacial hardness associated with brittle intermetallics. Reliability analysis based on a two-parameter Weibull distribution applied to twelve replicate welds at the optimal parameters yielded a mean UTS of 240.48 MPa and a 90% survival probability at 237.9 MPa. These findings demonstrate that a Ni interlayer, combined with appropriate FSW parameter optimization, can produce reliable dissimilar Al–Ti joints suitable for demanding structural applications.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 3","pages":"865 - 883"},"PeriodicalIF":2.5,"publicationDate":"2026-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147337385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fatigue assessment of 316L DED-arc structures considering individual surface topography","authors":"Jan Schubnell,&nbsp;Paul Oliver David,&nbsp;Fabian Keil,&nbsp;Ardeshir Sarmast,&nbsp;Igor Varfolomeev,&nbsp;Markus Köhler,&nbsp;Klaus Dilger,&nbsp;Jörg Baumgartner","doi":"10.1007/s40194-026-02331-3","DOIUrl":"10.1007/s40194-026-02331-3","url":null,"abstract":"<div><p>The surface topography of parts and components manufactured by direct energy deposition arc (DED-arc) based on additive manufacturing is crucial for fatigue behavior. In this study, DED-arc specimens made of AISI 316L are characterized according to their mechanical properties and surface topography (waviness). The specimen surface was digitized by 3D scanning. Fatigue tests were performed in as-printed condition and milled condition (flat surface). The crack initiation locations of each individual specimen were determined to correlate individual geometry and failure location. The specimens made of 316L showed a significant waviness of up to 1.4 mm. The fatigue tests were evaluated with different concepts: the nominal stress approach based on different definitions of the cross sections, as well as local approaches like the maximum stress (notch stress), critical distance, or stress gradient approach. The scatter in the S–N curves was significantly reduced by using all three local approaches, with the lowest scatter observed using the maximum stress approach. The fatigue life was assessed by linear elastic fracture mechanics (LEFM) using best practice input parameters based on the fatigue life assessment of welded joints. By LEFM, conservative fatigue life values could be reached according to the experiments, especially for low load levels. A combination of local approaches with LEFM leads to a very good agreement in the investigated case.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 5","pages":"1831 - 1847"},"PeriodicalIF":2.5,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02331-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147727342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}