Journal of Materials Processing Technology最新文献

{"title":"Metal droplet ejection technology based on water hammer effect for additive manufacturing","authors":"Guofang Hu ,&nbsp;Boce Xue ,&nbsp;Yanzhen Zhang ,&nbsp;Xiaodi Zhao ,&nbsp;Yuyao Wu ,&nbsp;Weiwei He ,&nbsp;Fenglin Hao ,&nbsp;Jianhao Zhu ,&nbsp;Zihao Li ,&nbsp;Dege Li ,&nbsp;Yanqing Zhang ,&nbsp;Mingyu Yan ,&nbsp;Runsheng Li","doi":"10.1016/j.jmatprotec.2025.118785","DOIUrl":"10.1016/j.jmatprotec.2025.118785","url":null,"abstract":"<div><div>Currently, in the field of molten droplet jetting for metal additive manufacturing, existing technologies such as pneumatic, piezoelectric, and magnetohydrodynamic methods face challenges in balancing device complexity, droplet ejection stability, and ejection frequency due to inherent limitations in their driving mechanisms. This study advances the traditional theories and techniques of droplet-based metal additive manufacturing by introducing a novel water hammer-based molten droplet jetting method. Through micron-scale rapid reciprocating motion of the jet tube along its axial direction, pulsed pressure is generated, enabling stable, efficient, and on-demand jetting of molten metal. The investigation systematically analyzed the effects of displacement, nozzle diameter, motion period, and liquid column height on the ejection behavior. The effects of different process parameters on pulsed pressure and jetting behavior were investigated. An increase in jet tube displacement or liquid column height, as well as a decrease in nozzle diameter, results in greater pulsed pressure, leading to higher droplet flight velocity. The additive manufacturing capabilities of this method for two-dimensional and three-dimensional structures have been validated.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118785"},"PeriodicalIF":6.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relaxation of residual stress in aluminum alloy rings by pulsed high magnetic field: Relieving mechanisms and performance evaluation","authors":"Xiaoxiang Li ,&nbsp;Xinyu Tang ,&nbsp;Mengxian Li ,&nbsp;Qiyuan Liu ,&nbsp;Zhan Tuo ,&nbsp;Quanliang Cao ,&nbsp;Liang Li","doi":"10.1016/j.jmatprotec.2025.118778","DOIUrl":"10.1016/j.jmatprotec.2025.118778","url":null,"abstract":"<div><div>Residual stress is commonly present in metal components, potentially leading to structural instability and reduced strength. Thus, effective elimination of residual stress is essential in manufacturing large metal components. Traditional methods for stress relief include energy-based and mechanical approaches. However, energy-based methods are time-consuming and can weaken component strength, while mechanical methods may damage contact surfaces and cause localized stress concentrations. This paper introduces a novel technique for relaxing residual stress using pulsed high magnetic fields. The method applies a pulsed magnetic field to the ring’s inner surface, inducing a strong, non-contact Lorentz force that triggers slight plastic deformation, releasing residual stress in the elastic regions. Remarkably, the process takes only a few milliseconds. The study examines the mechanisms behind residual stress relief via pulsed magnetic fields and designs a device for stress elimination in large aluminum rings. Initial validation through bulging experiments on 6061 aluminum alloy rings (118 mm diameter) showed that the electromagnetic bulging process improves micro-deformation uniformity, promotes dislocation motion, generates sub-grain structures, and refines grains, thereby relieving stress. A large-scale electromagnetic bulging platform was then designed for 5A06 aluminum alloy rings (717 mm diameter). In-situ experiments demonstrated that a plastic deformation of 1 % eliminated up to 84.9 % of residual stress, indicating substantial stress relief. Finally, the study compared the effectiveness of stress elimination across different surfaces under various discharge bulging modes and analyzed the reasons for these differences. This method significantly enhances the efficiency and effectiveness of residual stress elimination in large aluminum alloy rings.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118778"},"PeriodicalIF":6.7,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Manufacture of ultra-smooth surface with low damage by elastic emission machining","authors":"Weihao Ma ,&nbsp;Jiahui Li ,&nbsp;Xinquan Zhang ,&nbsp;Mingjun Ren ,&nbsp;Xi Hou","doi":"10.1016/j.jmatprotec.2025.118780","DOIUrl":"10.1016/j.jmatprotec.2025.118780","url":null,"abstract":"<div><div>Extreme application scenarios require atomic-level surface smoothness without subsurface damage, particularly for hard and brittle materials prone to cracks and residual stress during mechanical processing. Elastic emission machining (EEM), a non-destructive atomic-level material removal method, has gained significant attention. However, its ultra-smooth surface generation mechanism remains underexplored. This study comprehensively compares the surface morphology, subsurface damage, and material properties before and after EEM polishing from a multi perspective. EEM preferentially removes protruding defects, whereas pit-type subsurface defects with residual compressive stress require a greater material removal depth. Micron scratch experiments reveal the mechanisms of EEM in smoothing and flattening defects, demonstrating its effectiveness in eliminating micron-scale scratches and enabling the conformal polishing of submillimetre microstructure. EEM achieves ultra-smooth surfaces with roughness below 0.1 nm root mean square on fused quartz, monocrystalline silicon, and ULE. The surface and internal lattice integrity of monocrystalline silicon confirm the non-destructive polishing capability of EEM. Power spectral density calculation indicate that EEM can eliminate spatial wavelength errors in the micron to the nanometre scale. This study validates the potential of EEM in high-performance optical component manufacturing and provides valuable references for achieving non-destructive atomic-level processing.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118780"},"PeriodicalIF":6.7,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructural mechanisms and mechanical behavior of friction-stir-welded Mg alloy laminate joints","authors":"Junlei Zhang ,&nbsp;Haojie Zhang ,&nbsp;Xiang Chen ,&nbsp;Zulai Li ,&nbsp;Guangsheng Huang","doi":"10.1016/j.jmatprotec.2025.118779","DOIUrl":"10.1016/j.jmatprotec.2025.118779","url":null,"abstract":"<div><div>Achieving reliable welding of multi-layered magnesium laminates is pivotal for advancing lightweight structural applications in energy-efficient transportation. However, the welding process and resultant joint properties of such complex laminates are issues of concern in material processing. This study aims to investigate the generic scientific principles governing the weldability and mechanical behavior of multi-layered Mg laminates using friction stir welding as a case study. An AZ31/Mg-6Zn-1Mn-2Gd/AZ31 laminate was successfully welded at 1000 rpm (rotation speed)–100 mm/min (welding speed) but not at 800 rpm–100 mm/min. The microstructural evolution, deformation behavior, and mechanical properties of the laminate joints were systematically investigated. The results indicated that both the AZ31 and Mg-6Zn-1Mn-2Gd layers in the laminate joint presented an approximately symmetrical texture distribution from the advancing side to the retreating side, with the texture intensity of the AZ31 layer higher than that of the Mg-6Zn-1Mn-2Gd layer. Tensile testing revealed strain localization, with mechanical properties (yield strength: 119 MPa, ultimate tensile strength: 211 MPa, elongation: 6.1 %) between single-material AZ31 and Mg-6Zn-1Mn-2Gd joints but worse than those of the initial laminate. The laminate joint ultimately fractured near the nugget zone interface on the advancing side. This was attributed to the fluctuation in the Schmid factor for basal slip and extension twinning, which were determined by the texture distribution. The current investigation provides insights into the correlation among the process parameters, microstructural evolution, and mechanical performance of Mg alloy laminate joints.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118779"},"PeriodicalIF":6.7,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formation mechanism and prediction model for peripheral coarse grain of high-strength aluminum alloy thermoplastic forming component: A case study on 2195 Al-Li alloy extrusion profile","authors":"Yongxiao Wang ,&nbsp;Guoqun Zhao ,&nbsp;Xiao Xu ,&nbsp;Xiaoxue Chen","doi":"10.1016/j.jmatprotec.2025.118776","DOIUrl":"10.1016/j.jmatprotec.2025.118776","url":null,"abstract":"<div><div>Peripheral coarse grain defect often forms in high-strength aluminum alloy components, which pose great risks to service reliability and safety in aerospace applications. The prediction and suppression of this defect has become fundamental scientific challenges. To address this, this study takes the extrusion of 2195 Al-Li alloy as a case study to explore three key scientific issues: the formation mechanism of peripheral coarse grain, prediction models, and suppression strategies. It indicates that the formation of peripheral coarse grains primarily occurs in areas of plastic strain accumulation. As the plastic strain increases, a thicker layer of peripheral coarse grains is formed. The fundamental formation mechanism of peripheral coarse grain involves two primary steps. Initially, the accumulation of high plastic strain triggers dynamic recrystallization and grain refinement. Subsequently, during solid solution treatment, rapid grain boundary migration driven by large curvature leads to the coarsening of the fine grains. The prediction models for recrystallization and grain coarsening were established, which were embedded finite element software and successfully predicted the recrystallization driving force, recrystallization fraction, grain size, and grain coarsening rate in extrusion processing. Based on these findings, the strategies to suppress the peripheral coarse grain were proposed. This study fundamentally establishes a transferable framework that connects the thermoplastic forming process of high-strength aluminum alloys with the prediction and control of peripheral coarse grains, which allows for more reasonable process optimization strategies. This generic approach thus offers predictive guidelines for optimizing the microstructure and properties of other high-strength aluminum alloys.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118776"},"PeriodicalIF":6.7,"publicationDate":"2025-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143427994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysing the reduction in buckling limit of a flexible roll formed flange due to shape imperfection","authors":"Achuth Sreenivas ,&nbsp;Buddhika Abeyrathna ,&nbsp;Bernard Rolfe ,&nbsp;Matthias Weiss","doi":"10.1016/j.jmatprotec.2025.118767","DOIUrl":"10.1016/j.jmatprotec.2025.118767","url":null,"abstract":"<div><div>Flexible roll-forming can form high-strength sheet metals into components with complex cross-sections but widespread application is limited by flange wrinkling. Previous work has suggested that the low buckling limit in flexible roll forming may be due to the local contact of the forming roll with the metal sheet which produces an imperfection in the flange. In this study, a new plate buckling test is presented and applied to study the effect of imperfections on the buckling limit for conditions that represent flange deformation in flexible roll forming. This is combined with a finite element analysis approach to determine the level of imperfection in a flexible roll formed flange and used to estimate the reduction of the flange buckling limit due to shape imperfection. The results of this study provide for the first time experimental and analytical evidence that the theoretical buckling limit in a flexible roll formed flange is significantly reduced by flange imperfections. The experimental plate buckling test combined with the finite element analysis method for estimating imperfection levels enables the analysis of the effect of forming parameters and geometric conditions on flange imperfection and buckling behaviour and therefore provides a promising alternative to conventional finite element analysis for flexible roll forming process optimisation.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118767"},"PeriodicalIF":6.7,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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":"Anisotropy mechanism of material removal and damage formation in single crystal 4H-SiC scratching","authors":"Xiaoyu Bao,&nbsp;Wen Zheng,&nbsp;Huixin Xing,&nbsp;Xingyu Wang,&nbsp;Qingliang Zhao,&nbsp;Yong Lu,&nbsp;Sheng Wang","doi":"10.1016/j.jmatprotec.2025.118768","DOIUrl":"10.1016/j.jmatprotec.2025.118768","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Single crystal 4H-SiC, the third-generation semiconductor material, exhibits excellent properties in short wavelength optical components. However, the high brittleness and hardness of material itself present significant challenges for machining It is crucial to investigate the anisotropy dependence of damage formation and material removal mechanism. The scratching experiments of varying crystallographic orientations online monitored using the acoustic emission (AE) signals and force signals. The surface and subsurface morphologies of the scratch grooves on the C plane, M plane and A plane with different crystallographic orientations were investigated. The anisotropic characteristics of material removal were preliminarily revealed by examining the scratch critical depth. Fast Fourier Transform (FFT) of AE signals was utilized to extract peak frequencies associated with material removal behavior. The peak value of signal frequency at 78.71 kHz and 82.82 kHz indicated the pronounced plastic removal, while that at 82.82 kHz and 91.88 kHz exhibited the positive correlation with the salience of brittle fracture removal. The variations in scratch orientation on the same plane were reflected in the peak amplitude of the medium frequency bands. Surface morphology revealed significant differences, which were affected by the material atomic arrangement and crystal orientation characteristics, and thus affected the stress distribution and crack propagation behavior. Slip deformation was the primary mechanism for plastic flow in materials, which delayed material fracture. As the stress concentration was reached, shear stress facilitated the cleavage of Si-C bonds, which propagated along slip/twinning planes. Furthermore, the anisotropic crystal structure of the single crystal 4H-SiC resulted in significant differences in mechanical responses. The atom arrangement and bonding characteristics endowed the material deformation capabilities. Along specific crystallographic orientations on the C plane, the robust atomic bonds impeded the material ability to relieve stress through dislocation slip, which resulted in a pronounced brittle fracture tendency. The changes in friction coefficients were related to crystallographic orientation, it fluctuated most significantly on the C plane, while remained relatively stable on the M plane. According to the stress field model, compressive stress induced the nucleation of lateral cracks aligned with the direction of the compressive forces, while tensile stress facilitated the nucleation and propagation of median cracks. The subsurface crack propagation behavior was influenced by the anisotropy in the crystal structure, local stress field distribution and interatomic bond strength. The propagation direction of subsurface cracks exhibited anisotropy depending on the scratch crystallographic plane. Specifically, lateral cracks propagated horizontally and deflected by approximately 30°, while median cracks propagated v","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118768"},"PeriodicalIF":6.7,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143446114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An optimization strategy based on critical recrystallization strain to improve the recrystallization rate of ultrasonic impact treatment assisted laser directed energy deposition","authors":"Chuanming Liu ,&nbsp;Chunhuan Guo ,&nbsp;Tao Dong ,&nbsp;Fengchun Jiang ,&nbsp;Zubin Chen ,&nbsp;Wenyao Sun ,&nbsp;Guorui Jiang ,&nbsp;Zhen Wang ,&nbsp;Shubang Wang ,&nbsp;Haixin Li","doi":"10.1016/j.jmatprotec.2025.118774","DOIUrl":"10.1016/j.jmatprotec.2025.118774","url":null,"abstract":"<div><div>In laser directed energy deposition (LDED), the epitaxial growth of long columnar grains often results in performance anisotropy in the component. Severe plastic deformation is a method commonly employed to refine grains. However, current research tends to focus on applying larger pressure loads and strains, which increases the demand for auxiliary equipment and reduces the convenience of application. In this study, we design and optimize a hybrid manufacturing method that combines synchronous ultrasonic impact treatment (UIT) with LDED, leveraging the cumulative characteristics of ultrasonic impact micro-deformation and the principle of critical recrystallization strain. Through mechanical compression and heat treatment experiments, we establish the strain-recrystallization relationship of the material and identified the minimum plastic strain necessary for achieving the maximum recrystallization rate (as the critical recrystallization effective strain). We predicted the plastic strain transfer depth under the current impact parameters using a model and optimized the thickness of the single deposition layer to prevent the recrystallization zone from being covered by the remelted molten pool. Using 316L stainless steel as the verification material, we induced synchronous recovery recrystallization at an exceptionally low output pressure (about 600 N). This optimization led to a significant 56 % refinement in grain size. Compared to the unoptimized experiment, the recrystallization rate increased from 9.14 % to 25.75 %. Furthermore, the yield strength of the material improved by 34 % (compared to a 19 % increase without optimization), all while maintaining high ductility. Additionally, we elucidated the strain and temperature conditions achieved during synchronous recovery recrystallization through a finite element model, and verified the accuracy of this model, allowing for the method's extension to other materials. These findings significantly reduce the demand for high pressure loads on equipment in deformation strengthening methods and enhance practicality.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118774"},"PeriodicalIF":6.7,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143437352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resistive thermal fusion interface: A novel additive manufacturing process of titanium alloy","authors":"Jiawen Lv ,&nbsp;Bobo Li ,&nbsp;Zhanxin Li ,&nbsp;Yitao Chen ,&nbsp;Jingchi Liu ,&nbsp;Bingheng Lu","doi":"10.1016/j.jmatprotec.2025.118773","DOIUrl":"10.1016/j.jmatprotec.2025.118773","url":null,"abstract":"<div><div>Additive manufacturing of titanium alloy has promoted their wider application in the aerospace and automotive industries. However, safety, cost and forming quality pose serious challenges to existing additive manufacturing technologies. Additionally, complete melting and rapid cooling inhibit the gas from escaping in the melt pool during solidification, leading to the presence of pores inside the sample, which deteriorates the properties of components. Herein, a novel additive manufacturing process of resistive thermal fusion interface with low cost is presented. The contact resistance heat is generated when the current passes through the contact interface between metal wires, which causes the interface to fuse while the rest part of material remains solid. This novel additive manufacturing process was employed to fabricate Ti-5Al-2.5Sn Ti-alloy components in this work. The macrostructure, defects feature, grain structure, tensile properties of the additively manufactured samples with different currents were analyzed systematically. The results reveal that, components without pore defects are obtained by selecting appropriate parameters. Samples possess strength-ductility synergy (yield strength of 864 ± 7 MPa, ultimate tensile strength of 896 ± 4 MPa and elongation of 17.7 ± 1.11 %), which is similar to samples fabricated by L-PBF with annealing treatment. Besides, the mechanisms of resistive thermal fusion interface as well as the microstructure–mechanical property relationships were elucidated in detail. Therefore, this work provides a promising way to fabricate high performance titanium alloy.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118773"},"PeriodicalIF":6.7,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the structural evolution of Al–15Sn–1Cu alloys solidified at different electromagnetic vibration frequencies","authors":"Ganpei Tang,&nbsp;Zhe Sun,&nbsp;Boyi Luo,&nbsp;Wenhao Lin,&nbsp;Zhongze Lin,&nbsp;Tianxiang Zheng,&nbsp;Bangfei Zhou,&nbsp;Peijian Shi,&nbsp;Qiang Li,&nbsp;Chunmei Liu,&nbsp;Haibiao Lu,&nbsp;Zhe Shen,&nbsp;Biao Ding,&nbsp;Yunbo Zhong","doi":"10.1016/j.jmatprotec.2025.118771","DOIUrl":"10.1016/j.jmatprotec.2025.118771","url":null,"abstract":"<div><div>For most alloys, columnar grains can lead to solidification defects and mechanical property anisotropy, making it a significant challenge in metallurgical sciences to promote columnar-to-equiaxed transition and control segregation. This study investigated the effects of convection induced by electromagnetic vibration frequency on the evolution of the directional solidification structure of Al–15Sn–1Cu alloys. The experimental results revealed that as the electromagnetic vibration frequency decreased from 100 to 1 Hz, the solidification front shape gradually transformed from sloping to planar. Moreover, the number of equiaxed grains increased as the frequency decreased, ultimately leading to the columnar-to-equiaxed transition at 1 Hz. The numerical results indicated that the formation of the planar solidification front can be attributed to a more uniform solute distribution and temperature oscillations. Additionally, the oscillatory flow-induced back-and-forth solute transport distance increases with decreasing frequency. Consequently, dendrite fragmentation is promoted as inter-dendrite solute fluctuations increase. The columnar-to-equiaxed transition occurs when the growth of columnar dendrites is completely blocked by equiaxed grains grown from the dendrite fragmentation ahead of them. Furthermore, owing to solute homogenisation and refinement of the solidification structure, a fine and uniform distribution of Sn phases in the Al matrix was achieved at 1 Hz. This study elucidates the effects of oscillatory convection driven by electromagnetic vibration on the temperature, solute transport behaviour, and directional solidification structure. These findings provide critical insights and practical guidelines for the production of fine and uniform equiaxed grain structures using electromagnetic vibration.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"338 ","pages":"Article 118771"},"PeriodicalIF":6.7,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143421272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}