Welding in the World最新文献

{"title":"A review of the current status of transient liquid phase bonding of powder metallurgy superalloys","authors":"Xinlei Ding,&nbsp;Yunjia Huang,&nbsp;Wei Guo,&nbsp;Yeming Guo","doi":"10.1007/s40194-026-02406-1","DOIUrl":"10.1007/s40194-026-02406-1","url":null,"abstract":"<div><p>In the field of welding superalloys, the complexity and high degree of alloying in these materials render most welding methods unsuitable for their application. Research on superalloy welding is scarce, with studies on powder metallurgy superalloys being even rarer. Based on the current state of research on powder metallurgy superalloys, the existing challenges in their joining processes are summarized in this work, and corresponding targeted solutions are proposed. In addition, the coupled optimization of interlayer design and post-bond heat treatment for liquid phase diffusion bonding represents a key research focus and a promising direction for future studies.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 6","pages":"2527 - 2538"},"PeriodicalIF":2.5,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147985270","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":"Surface pretreatment of 6063 aluminum alloy and strengthening mechanism of vacuum diffusion bonding joint","authors":"Jiafen Song,&nbsp;Lichi Ma,&nbsp;Yunjia Huang,&nbsp;Shiming Xu,&nbsp;Yu Peng,&nbsp;Jiangtao Xiong,&nbsp;Jinglong Li","doi":"10.1007/s40194-026-02372-8","DOIUrl":"10.1007/s40194-026-02372-8","url":null,"abstract":"<div><p>The diffusion bonding of 6063 aluminum alloy with surface pretreatment was carried out in this paper. The 6063 aluminum alloy (AA6063) is often used in the manufacture of micro-channel heat exchangers (PCHE). However, due to the existence of a stable surface oxide film (Al₂O₃) with a high melting point, which prevents the close contact of the surface to be bonded and the diffusion of atoms. This paper designed the acid and alkali washing cleaning before the bonding process. Three protection schemes were designed for the cleaned surface protection, namely, ethanol protection, α-terpineol surface protection, and magnesium powder terpineol mixed protection. The bonding temperature of diffusion bonding was 540 ~ 580 °C, the pressure was 4 MPa, and the bonding time was 120 min. The microstructure of the joint was studied by scanning electron microscopy. The mechanical properties of the joint were evaluated by a tensile test. The results show that with the optimal process of 570 °C–4 MPa–120 min, the α-terpineol-protected joint achieved a tensile strength of 113.3 MPa and an elongation of 28.1%. It provides a feasible design idea for the diffusion bonding of 6063 aluminum alloy.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 6","pages":"2495 - 2504"},"PeriodicalIF":2.5,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147985266","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":"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":"Study on the brazing process of TC4 titanium alloy/304 stainless steel and the effect of gap on braze joint performance","authors":"Shuang Xie,&nbsp;Guanyu Yao,&nbsp;Jianqiao Xiong,&nbsp;Jin Ouyang,&nbsp;Jingqing Chen,&nbsp;Hui Chen","doi":"10.1007/s40194-026-02424-z","DOIUrl":"10.1007/s40194-026-02424-z","url":null,"abstract":"<div><p>The joining of titanium alloys and stainless steels is critically required in aerospace and other fields, frequently accomplished through brazing. This paper investigates vacuum brazing of TC4 titanium alloy and 304 stainless steel using Ag70-Cu26-Ti4 filler metal. Through SEM/EDS, XRD characterization, and shear tests, the effects of process parameters on interfacial microstructure evolution and mechanical properties were analyzed. The filler metal’s fluidity at different gaps and its impact on joint strength were examined. Results demonstrate that the joint achieved optimal shear strength of 191 MPa at 830 °C/5 min, with appropriate reaction layer thickness and dispersed brittle Cu-Ti phases. Elevated temperature caused Cu-Ti phase coarsening throughout the brazing seam, reducing strength. At 0.21 mm gap, the filler metal showed optimum fluidity with 31 mm filling distance, yielding maximum shear strength of 127 MPa at 850 °C/5 min. Reaction layer growth kinetics revealed activation energies of 111.0 kJ·mol⁻¹ in Zone III (TC4 side) and 244.5 kJ·mol⁻¹ in Zone I (stainless steel side), confirming easier diffusion of Cu and Ti atoms in the titanium alloy. This study provides theoretical guidance for suppressing brittle phase formation and optimizing brazing gap design.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 6","pages":"2539 - 2553"},"PeriodicalIF":2.5,"publicationDate":"2026-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147985210","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 hot isostatic pressing on the microstructure and mechanical properties of wide-gap brazed joints","authors":"Jie Liu,&nbsp;Mingsheng Wang,&nbsp;Xiangwei Jiang,&nbsp;Zishu Sun,&nbsp;Song Zhang,&nbsp;De Wang,&nbsp;Chunhua Zhang,&nbsp;Jiasheng Dong","doi":"10.1007/s40194-026-02430-1","DOIUrl":"10.1007/s40194-026-02430-1","url":null,"abstract":"<div><p>Wide-gap brazing (WGB) is an economically efficient and widely adopted technique for repairing superalloy components. However, controlling the formation of detrimental brittle intermetallic phases remains challenging even with optimized filler materials and brazing parameters. This study systematically investigates the effect of introducing hot isostatic pressing (HIP) as an intermediate process on the microstructure and mechanical properties of layered WGB CM247LC superalloy joints. Combining X-ray computed tomography (XCT), microstructural characterization, and mechanical testing, the results demonstrate that HIP treatment effectively eliminated internal porosity and reduced the void volume fraction from approximately 0.2% to 0.002%. Furthermore, HIP promoted boron diffusion, significantly reduced the amount and continuity of brittle boride phases. Mechanical tests confirmed that these microstructural improvements led to a remarkable enhancement in joint performance, including a 12-fold increase in stress rupture life at 900 °C/315 MPa and a 24% improvement in tensile strength. The findings underscore HIP’s critical role in achieving high-integrity repairs for wide-gap brazed superalloy joints.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 6","pages":"2555 - 2568"},"PeriodicalIF":2.5,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147985211","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":"Developing a methodology to assess liquid metal embrittlement impact on the fatigue life of resistance spot welds","authors":"M. Ullrich,&nbsp;S. Jüttner","doi":"10.1007/s40194-026-02421-2","DOIUrl":"10.1007/s40194-026-02421-2","url":null,"abstract":"<div><p>Third-generation advanced high-strength steels (3G AHSS) are widely used in automotive applications due to their exceptional mechanical properties, including high tensile strength and fracture toughness. Resistance spot welding is the dominant joining process for these steels in the body-in-white production due to the high productivity and automation capability. Though exhibiting satisfying welding current ranges, AHSS can have the downside of showing zinc-induced liquid metal embrittlement (Zn-LME), a phenomenon in which the exposure of the susceptible base material to the liquid zinc coating in combination with the induced tensile stresses during resistance spot welding can lead to cracking of varying severity. The presence of zinc-induced LME cracks can result in an unexpected failure of the component due to potential premature crack initiation and propagation under a mechanical load. While extensive research has been conducted on the effects of LME on static mechanical properties such as tensile strength and fracture toughness, its impact on fatigue life—a critical factor in the automotive application—remains less well understood. Fatigue failure can occur earlier as the presence of LME can accelerate the crack growth under cyclic loading. Understanding the interplay between LME-induced cracks formed during resistance spot welding and fatigue behavior is essential for improving the reliability and widening the application field of 3G AHSS. This study, which is the first part of a larger investigation, is aimed at developing a methodology for analyzing the influence of zinc-induced LME on the fatigue life of third-generation advanced high-strength steels (3G AHSS), focusing on the fatigue crack initiation and propagation mechanism under cyclic loading. To achieve this, LME cracks were generated via the usage of a decreasing electrode force profile and the reproducibility was investigated. The LME crack surface was investigated with stereo and scanning electron microscopy. The fatigue test for a specimen with severe LME cracking was monitored via digital image correlation (DIC), which enabled the evaluation of critical areas. The derived methodology serves as a guideline for quantifying the influence on LME cracks on the fatigue life and thereby assisting the development process of new materials and parts. In upcoming investigations, the methodology will be used to evaluate the influence of specific LME crack sizes and types.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 7","pages":"3141 - 3152"},"PeriodicalIF":3.1,"publicationDate":"2026-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02421-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261967","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":"Investigation of a multi-cathode TIG arc process for additive manufacturing applications","authors":"Paul Schilling,&nbsp;Tim Ungethüm,&nbsp;Paul Sanderbrand,&nbsp;Hans Christian Schmale","doi":"10.1007/s40194-026-02414-1","DOIUrl":"10.1007/s40194-026-02414-1","url":null,"abstract":"<div><p>This study investigates a novel tungsten inert gas double-electrode (TIG-DE) welding process with integrated coaxial hot-wire feeding for additive manufacturing applications. By combining arcs generated by multiple cathodes with independent wire preheating, the process aims to overcome the limitations of conventional single-electrode TIG systems, particularly with respect to directional dependence and limited deposition rates. A custom-built demonstrator system was used to systematically analyze the arc behavior, weld bead formation, and process stability under various parameter conditions. Arc pressure measurements confirmed the isotropy of the arc shape under optimized electrode configurations. Blind seam trials in orthogonal directions revealed minimal geometric deviations, verifying the directional independence of the process, which is a major advantage over conventional processes. The integration of an ohmic preheating unit enabled stable wire feeding at high speeds and significantly reduced eccentricities of the weld bead. Compared to the cold-wire TIG process, the hot-wire process exhibited a broader process window and higher productivity, with deposition rates exceeding 1 kg h<span>(^{-1})</span> and seam height deviations consistently below 1 mm. These findings highlight the capability of the developed process to enable geometrically consistent and directionally independent layer buildup, providing a robust foundation for further development of wire-based additive manufacturing using TIG technology.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 8","pages":"3473 - 3484"},"PeriodicalIF":3.1,"publicationDate":"2026-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40194-026-02414-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148695488","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":"Magnetic pulse-assisted semi-solid brazing of copper-aluminum tubes: solid-liquid interface and defect formation","authors":"Jiawang Zhang,&nbsp;Shangyu Huang,&nbsp;Zhenghua Meng,&nbsp;Jianhua Hu,&nbsp;Zhenglei Rui","doi":"10.1007/s40194-026-02416-z","DOIUrl":"10.1007/s40194-026-02416-z","url":null,"abstract":"<div><p>This study develops a coupled finite element method-smoothed particle hydrodynamics (FEM-SPH) model to elucidate interfacial evolution mechanisms during magnetic pulse-assisted semi-solid brazing (MPASSB) of copper-aluminum tubular joints. Through an integrated numerical-experimental approach, we systematically examined the interdependent effects of impact parameters (velocity <i>v</i>, angle <i>θ</i>) and filler metal characteristics (apparent viscosity <i>μ</i>, spatial distribution) on interfacial morphology development. Key findings reveal that impact parameters (<i>v</i>, <i>θ</i>) predominantly govern interfacial waveform attributes: both wavelength and amplitude exhibit positive correlations with increasing impact velocity and angle. Reduced filler metal viscosity (<i>μ</i> &lt; 41.7 Pa·s) promotes interfacial wave formation and vortex generation, while increased filler-copper spacing enhances copper-side waveform definition. Experimental validation through parametric brazing trials confirmed the synergistic effects of <i>v</i> and <i>μ</i> on interfacial wave dimensions. Microstructural analysis demonstrates aluminum-side porosity originates from particle entrapment in semi-solid filler metal, where enhanced fluidity facilitates pore migration. Conversely, copper-side porosity arises from oxide residue accumulation, mitigated through viscosity optimization. High-strain-rate collision dynamics generate sequential jetting phenomena: primary jets induce interfacial mixing while re-entrant jets establish periodic waveform patterns through cyclic material interaction.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 7","pages":"3123 - 3139"},"PeriodicalIF":3.1,"publicationDate":"2026-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261842","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":"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":"Microstructure and defects formation mechanism of inertia friction welded joint of GH4151 superalloy with high γʹ phase content","authors":"Zhonglin Wang,&nbsp;Xingfei Xie,&nbsp;Jinglong Qu,&nbsp;Jinhui Du,&nbsp;Yueguang Yu","doi":"10.1007/s40194-026-02339-9","DOIUrl":"10.1007/s40194-026-02339-9","url":null,"abstract":"<div><p>Nickel-based superalloy GH4151 has excellent high-temperature strength, but its high γʹ content and complex compositional and microstructure lead to poor weldability. The microstructure and defect formation mechanism of the joints were analyzed by adjusting the welding pressure of inertia friction welding (IFW) combined with hot deformation experiments. The results show that at low welding pressure, the welding defects are non-uniform grains, harmful precipitates (Laves and γ-γ′ eutectic), and microcracks. The formation of these defects is associated with dynamic recrystallization, the γʹ compositional liquefaction, and the stress concentration caused by carbides. At medium welding pressure, the deformation uncoordination of primary γ′ and carbides at the interface with the matrix, as well as the shear force at the weld interface, led to initial cracks, and the residual stresses generated by the precipitation of γ′ during post-weld cooling led to secondary cracks. Joints with favorable microstructure were obtained at high welding pressure, with uniform and fine grains and tertiary γ′ in the weld zone. Hot deformation experiments show that the rapid dissolution behavior of γʹ under rapid heating and deformation in the IFW process lead to microcracks. Meanwhile, the ultrahigh temperature at the weld interface causes alloy melting and the formation of harmful phases. Reasonably increasing the welding pressure can effectively suppress the liquefaction of γ′, enhance the healing capacity of pores and microcracks, and improve the flowability of plastic metal at the weld interface, thereby reducing the formation of welding defects and obtaining uniform and fine joint microstructure and precipitates.</p></div>","PeriodicalId":809,"journal":{"name":"Welding in the World","volume":"70 7","pages":"2955 - 2972"},"PeriodicalIF":3.1,"publicationDate":"2026-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261793","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}