Welding in the World最新文献

{"title":"Influence of repair welding numbers on microstructure and mechanical properties of S355J2G4 steel welded joints","authors":"Xin Zhao,&nbsp;Chenghao Xie,&nbsp;Haiting Lv,&nbsp;Zhibin Yang","doi":"10.1007/s40194-025-02144-w","DOIUrl":"10.1007/s40194-025-02144-w","url":null,"abstract":"<div><p>In this study, original welds of 12 mm thick S355J2G4 steel used for railway vehicles were repaired through Metal Active Gas (MAG) welding to determine influence of repair welding numbers on microstructure and mechanical properties of welded joints. The results indicated that the weld macrostructure did not significantly change with increasing repair welding numbers, the phase composition of the microstructure in the heat affected zone were the same while the grain size slightly increased. The microhardness values on upper weld surface between the repaired and original weld fusion lines gradually reduced as repair welding number increased. Both the average yield and tensile strengths reduced with increasing repair welding numbers, while the average elongations remained nearly constant. The tensile specimens all fractured in base metal. There were no visible cracks appeared on surface of the bending test specimen. The average impact energy and median fatigue strength both presented gradual downward trends as repair welding number increased. The fatigue specimens of the 0R (original), 1R (repaired once), and 2R (repaired twice) welded joints all fractured in weld metal, while the fatigue specimens of the 3R (repaired thrice) welded joints fractured near fusion line, this change was primarily due to the serious joint softening as repair welding number increased. The above results indicated that the microstructure and mechanical properties of the repair-welded joints still could meet the application requirements even the repair welding number reached up to three, which could provide practical guidance for developing repair strategies in industrial applications.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 10","pages":"3165 - 3176"},"PeriodicalIF":2.5,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145062174","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":"In-service and repair welding of pressurized hydrogen pipelines–a review on current challenges and strategies","authors":"Kjell Erxleben,&nbsp;Sebastian Kaiser,&nbsp;Michael Rhode,&nbsp;Thomas Kannengiesser,&nbsp;Arne Kromm","doi":"10.1007/s40194-025-02127-x","DOIUrl":"10.1007/s40194-025-02127-x","url":null,"abstract":"<div><p>Hydrogen is the energy carrier for a sustainable future without fossil fuels. As this requires a reliable transportation infrastructure, the conversion of existing natural gas (NG) grids is an essential part of the worldwide individual national hydrogen strategies, in addition to newly erected pipelines. In view of the known effect of hydrogen embrittlement, the compatibility of the materials already in use (typically low-alloy steels in a wide range of strengths and thicknesses) must be investigated. Initial comprehensive studies on the hydrogen compatibility of pipeline materials indicate that these materials can be used to a certain extent. Nevertheless, the material compatibility for hydrogen service is currently of great importance. However, pipelines require frequent maintenance and repair work. In some cases, it is necessary to carry out welding work on pipelines while they are under pressure, e.g., the well-known tapping of NG grids. This in-service welding brings additional challenges for hydrogen operations in terms of additional hydrogen absorption during welding and material compatibility. The challenge can be roughly divided into two parts: (1) the possible austenitization of the inner piping material exposed to hydrogen, which can lead to additional hydrogen absorption, and (2) the welding itself causes an increased temperature range. Both lead to a significantly increased hydrogen solubility in the respective materials compared to room temperature. In that connection, the knowledge on hot tapping on hydrogen pipelines is rare so far due to the missing service experiences. Fundamental experimental investigations are required to investigate the possible transferability of the state-of-the-art concepts from NG to hydrogen pipeline grids. This is necessary to ensure that no critical material degradation occurs due to the potentially increased hydrogen uptake. For this reason, the paper introduces the state of the art in pipeline hot tapping, encompassing current research projects and their individual solution strategies for the problems that may arise for future hydrogen service. Methods of material testing, their limitations, and possible solutions will be presented and discussed.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 10","pages":"3141 - 3164"},"PeriodicalIF":2.5,"publicationDate":"2025-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-025-02127-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145062245","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 overlap laser welding parameters on the mechanical and microstructural properties of AISI 1018 and 301LN stainless steel joints","authors":"Payam Farhadipour,&nbsp;Narges Omidi,&nbsp;Pedram Farhadipour,&nbsp;Noureddine Barka,&nbsp;Claude Belzile,&nbsp;Abderrazak El Ouafi","doi":"10.1007/s40194-025-02114-2","DOIUrl":"10.1007/s40194-025-02114-2","url":null,"abstract":"<div><p>This study investigates the impact of laser overlap welding parameters on the mechanical and microstructural properties of dissimilar joints between AISI 1018 low-carbon steel and stainless steel 301LN. A series of experiments were conducted varying laser power, travel speed, and oscillation amplitude to determine optimal welding conditions. Tensile tests revealed that the welds exhibited significantly different strengths and displacements, with the optimal parameters achieving a maximum load of 39.6 kN and a displacement of 9.3 mm. Macrostructural analysis indicated that higher oscillation amplitudes resulted in broader but shallower welds, whereas lower amplitudes achieved deeper penetration. Microstructural examination showed varied phase formations, including martensite and bainite, influenced by the diffusion of alloying elements such as chromium and nickel. The formation of chromium carbides significantly enhanced the hardness of the fusion zone, with microhardness values reaching up to 470 HV at moderate penetration. Fractographic analysis of tensile-tested samples highlighted different fracture mechanisms, with optimal welds fracturing in the base material rather than the weld interface, indicating superior joint strength. This study provides critical insights into optimizing laser overlap welding parameters to enhance the mechanical performance and structural integrity of dissimilar metal joints, contributing to improved industrial welding practices.\u0000</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 9","pages":"2589 - 2607"},"PeriodicalIF":2.5,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163712","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":"Numerical study on the effect of constraint duration on stress and deformation in SUS301L stainless-steel plates during laser welding","authors":"Liu Zuguo,&nbsp;Qin Xinmao,&nbsp;Liao Jianhua,&nbsp;Wu Jiazhu","doi":"10.1007/s40194-025-02112-4","DOIUrl":"10.1007/s40194-025-02112-4","url":null,"abstract":"<div><p>The influence of external constraint time on the stress and deformation caused by laser welding of thin SUS301L stainless steel was quantitatively studied. Due to the inability to accurately control the fixture constraint time in the experiment, this paper uses a three-dimensional thermal elastoplastic finite element simulation method to study the deformation, stress, and strain changes of welded stainless steel plates under different fixture constraint times. In order to improve simulation accuracy, the relationship between mesh size and thermal input in finite element analysis is analyzed. The method of sequential coupling thermo-mechanic is proposed to analyze the transient temperature field and deformation during welding. The thermal and mechanical material properties used in the simulation follow a non-linear relationship as a function of temperature. Meanwhile, the accuracy of the simulation model was verified based on the temperature history by the K-type thermocouple and weld profile measured. The results show that the length of the clamp restraint time will indeed have a certain effect on the deformation after welding. Release of the clamp 25 s after the end of welding can effectively reduce the welding deformation from 1.3 to 1.21 mm, which is a 7% reduction.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 9","pages":"2573 - 2587"},"PeriodicalIF":2.5,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163711","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":"Design and modeling of pipeline welding robot based on Pieper criterion and construction of integrated intelligent welding system","authors":"Chuanhui Zhu,&nbsp;Zihao Wang,&nbsp;Zhiming Zhu,&nbsp;Jichang Guo","doi":"10.1007/s40194-025-02113-3","DOIUrl":"10.1007/s40194-025-02113-3","url":null,"abstract":"<div><p>The welding efficiency and weld formation quality of pipeline external welding are important factors that constrain the site laying speed and service performance of long-distance oil and gas pipeline. It is urgent to optimize the structure and function of pipeline welding equipment and control system, and improve the intelligent level of the external welding process. This paper focuses on improving weld bead formation quality during the pipeline all-position welding. Based on the Pieper criterion, a 5-degree of freedom (DOF) welding robot is designed. It can meet the control requirements of welding torch position and posture (WTPP) that comply with the welding process parameters at any welding position of pipeline. The kinematic model of the designed robot is established, and an analytical solution to its inverse kinematics is derived. Combined with the composite sensor based on combined laser line structured lights vision sensor and gravity sensor, the pipeline all-position intelligent welding system is integrally constructed. Based on this, the detection method of welding groove size and WTPP parameters is proposed. Through the designed program control strategy, the intelligent adjustment experiments of the WTPP were carried out during the pipeline all-position welding process. The lateral tracking deviation of welding torch was not more than 0.25 mm; the vertical tracking deviation was not more than 0.63 mm, and the posture angles feedback control deviation were not more than 0.8°. The good weld formation effect was obtained, which provides support for the improvement of the intelligent level of pipeline external welding. </p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 9","pages":"2853 - 2867"},"PeriodicalIF":2.5,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163229","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":"Evaluation of crack depth impact on HFMI-treated pre-fatigued welded bridge details","authors":"Martin Edgren,&nbsp;Joakim Hedegård,&nbsp;Zuheir Barsoum","doi":"10.1007/s40194-025-02102-6","DOIUrl":"10.1007/s40194-025-02102-6","url":null,"abstract":"<div><p>This study focuses on the utilization of high-frequency mechanical impact (HFMI) treatment for rehabilitating pre-fatigued steel bridge components. It incorporates time of flight diffraction (TOFD) for precise crack depth measurement, alongside strain range drop monitoring to enhance assessment accuracy. The experimental setup involves fillet weld specimens with cope hole geometry, using S355MC steel. The HFMI treatment process employs 3-mm diameter pins to achieve an HFMI indentation depth of 0.2 mm. The study demonstrated that HFMI treatment effectively extends the fatigue life of steel bridge components, showing significant improvements for cracks up to 1.2-mm deep. TOFD measurements, validated against manual optical measurements, consistently indicated crack depths within ± 0.1-mm accuracy. This precision is critical for assessing the HFMI treatment’s effectiveness in repairing pre-fatigued structures. The strain range drop method was used as a stop criterion to evaluate crack depth in real time, effectively reducing the number of TOFD measurements required during fatigue crack growth testing. The experimental results showed that HFMI treatment could improve fatigue life, moving specimens’ performance well above the IIW recommended FAT125 curve for treated steel details. In conclusion, this investigation confirms the significant potential of HFMI treatment for extending the life of pre-fatigued steel bridge components. The combined use of TOFD and strain range drop monitoring provides a robust framework for accurately assessing and optimizing HFMI treatment.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 8","pages":"2443 - 2458"},"PeriodicalIF":2.5,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-025-02102-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168526","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":"Optimizing welding angle for enhancing hybrid welding seam quality","authors":"Lingxiao Song,&nbsp;Peilei Zhang,&nbsp;Zufa Li,&nbsp;Junbo Feng,&nbsp;Xunzuo Su,&nbsp;Jixuan Li,&nbsp;Zhishui Yu","doi":"10.1007/s40194-025-02109-z","DOIUrl":"10.1007/s40194-025-02109-z","url":null,"abstract":"<div><p>In this research, the effects of the welding angle on the behavior of the molten pool, keyhole, and welding defects in the laser-MAG hybrid welding process of 14-mm-thick AH36 high-strength shipbuilding steel are thoroughly analyzed. High-speed photography was used to observe the behavior of the molten pool and keyhole, while synchronized oscilloscope measurements revealed a strong correlation between arc voltage fluctuations and keyhole oscillation frequencies, demonstrating the dynamic interplay between arc plasma and keyhole stability. The results reveal that the welding angle significantly affects the quality of weld formation, molten pool flow, keyhole behavior, collapse, and bottom hump, as well as spatter phenomena. When the welding angle is 82.5°, optimal weld formation quality is achieved, characterized by a stable molten pool shape and regular keyhole behavior. At a 75° welding angle, the molten pool shape and keyhole behavior exhibit significant instability, leading to poor weld formation. This results in the periodic formation of the narrowest throat on the surface of the molten pool, presenting a wide-narrow-wide serrated characteristic, which triggers surface collapse and hump defects. Furthermore, at a 97.5° welding angle, intense unstable fluctuations occur within the molten pool, causing the molten metal to overcome surface tension and bulge beyond the surface of the molten pool, forming violent fluctuations and a raised liquid column that progressively detaches from the molten pool to form spatter. The research findings indicate that an appropriate welding angle can optimize the behavior of the molten pool and reduce welding defects.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 9","pages":"2553 - 2571"},"PeriodicalIF":2.5,"publicationDate":"2025-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168101","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 strength assessment of HFMI-treated steel joints under bending loading","authors":"Martin Leitner,&nbsp;Antti Ahola,&nbsp;Masoud Moshtaghi,&nbsp;Timo Björk,&nbsp;Peter Brunnhofer,&nbsp;Christian Buzzi","doi":"10.1007/s40194-025-02100-8","DOIUrl":"10.1007/s40194-025-02100-8","url":null,"abstract":"<div><p>This study deals with the validation of the fatigue design values given in the IIW Recommendations for the HFMI Treatment for HFMI-treated steel joints under bending loading. In total, ten data sets involving T-joint specimens under bending loading with varying specimen geometries and base material yield strengths are investigated. The load stress ratio was <i>R</i> = <i>0.1</i> in all test series. The corresponding FAT-classes are defined on the basis of the IIW Recommendations for the HFMI Treatment in dependence of the structural detail and the yield strength of the base material. Furthermore, the thickness as well as certain thinness effect is covered by an IIW-recommended factor <i>f(t)</i> in one case leading to a design curve <i>HFMI-IIW with f(t)</i>. In another case, a factor <i>k</i>_<i>tb</i> based on the British Standard BS 7608 is additionally considered, which combines the thickness as well as bending effect. The corresponding design curve is denoted as <i>HFMI-IIW with k</i>_<i>tb</i>. A comparison of the fatigue test data points and the related statistically evaluated S/N-curve for each data set with the two approaches reveals that the design curve <i>HFMI-IIW with f(t)</i> leads to a conservative assessment for all data sets involved in this study. Also, a certain thinness effects is well covered and still a proper fatigue design should be ensured. Focusing on the design curve <i>HFMI-IIW with k</i>_<i>tb</i>, which additionally covers the bending effect, a conservative assessment is observed for almost all data sets. However, it is concluded that further test data especially for reduced plate thicknesses should be assessed to provide additional comparison results and ensure a conservative applicability for HFMI-treated steel joints under bending loading in any case.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 8","pages":"2433 - 2441"},"PeriodicalIF":2.5,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-025-02100-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166202","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 behaviour of 12-month corroded offshore steel joints under accelerated salt spray exposure: an experimental and numerical analysis","authors":"Sulaiman Shojai,&nbsp;Kram Kabha,&nbsp;Christian Woitzik,&nbsp;Moritz Braun,&nbsp;Elyas Ghafoori","doi":"10.1007/s40194-025-02043-0","DOIUrl":"10.1007/s40194-025-02043-0","url":null,"abstract":"<div><p>The fatigue strength of steel structures can decrease significantly when corrosion occurs. Pitting corrosion, in particular, can lead to locally high stress concentrations and may interact with existing stress concentrations from weld seams. Particularly in the case of offshore support structures, which are exposed to a corrosive environment and include several welded connections, this issue becomes relevant. Hence, in this study, butt- and fillet-welded joints of structural steel were exposed to accelerated corrosion in a salt spray chamber and then tested for fatigue strength. In order to investigate the long-term behaviour, the specimens were stored for 12 months in a salt spray chamber. Base material specimens were investigated as reference. All specimens were clean blasted and 3D scanned prior to the fatigue tests. It was shown for all specimens that the fatigue strength decreased after 12 months compared to the uncorroded reference tests. However, the fatigue reduction was different for the different geometries. The greatest reduction was observed for the base material from 282 to 122 N/mm², followed by butt-welded joints from 215 to 147 N/mm², and fillet-welded joints from 168 to 144 N/mm². As the fatigue strengths showed only minor difference after 12 months, an equalization effect can be assumed. The results show that a generalized reduction of the fatigue strength, in accordance with the guidelines, is not appropriate and therefore should be revised for a more accurate design of offshore support structures. Finally, numerical analysis based on 3D scans of the specimens was conducted and compared with the test results.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 8","pages":"2351 - 2369"},"PeriodicalIF":2.5,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-025-02043-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165329","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":"Residual stress reduction using a low transformation temperature welding consumable with focus on the weld geometry","authors":"Martin Hübner,&nbsp;Florian Dittmann,&nbsp;Arne Kromm,&nbsp;Igor Varfolomeev,&nbsp;Thomas Kannengießer","doi":"10.1007/s40194-025-02094-3","DOIUrl":"10.1007/s40194-025-02094-3","url":null,"abstract":"<div><p>Low transformation temperature (LTT) welding consumables represent an innovative approach to realize compressive residual stress in the weld seam and HAZ. LTT welding consumables use the volume-expanding martensitic phase transformation near room temperature to generate compressive residual stress during cooling. This article focuses on the weld geometry and its influence on residual stress reduction using an LTT welding consumable. For this purpose, layers with an LTT welding consumable were additionally applied to the front sides of conventionally welded longitudinal stiffeners. Different weld geometries of the second weld seam could be realized by varying the welding parameters. These samples were analyzed for geometric parameters, chemical composition, and residual stress. While the chemical composition and martensite start temperature (M_S) were only slightly influenced by parameter changes, a clear influence with regard to residual stress and weld geometry was observed. Depending on the shape of the second LTT weld seam, residual stress reductions of 200 to 500 MPa were achieved using the same LTT welding consumable.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"69 10","pages":"3129 - 3139"},"PeriodicalIF":2.5,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-025-02094-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145062335","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}