Journal of Materials Processing Technology最新文献

{"title":"Submerged arc additive manufacturing of duplex stainless steel: Effect of intrinsic heat treatment on microstructure, mechanical properties and pitting resistance","authors":"Fangjie Cheng ,&nbsp;Manye Xue ,&nbsp;Bo Zhang ,&nbsp;Shuai Yan ,&nbsp;Shaojie Wu","doi":"10.1016/j.jmatprotec.2025.118885","DOIUrl":"10.1016/j.jmatprotec.2025.118885","url":null,"abstract":"<div><div>In the additive manufacturing of duplex stainless steel (DSS), thermal cycle and material mismatch frequently result in the imbalance between austenite and ferrite and properties deterioration. Due to the limitations of heat input and forming conditions during the wire arc additive manufacturing (WAAM) process, the improvement of the deposition efficiency faces significant challenges. In this study, submerged arc additive manufacturing (SAAM) with high deposition efficiency is utilized for the fabrication of 2209 DSS with heat inputs of 1.3 kJ/mm, 1.5 kJ/mm, 2.0 kJ/mm and 2.4 kJ/mm. The unique intrinsic heat treatment (IHT) inherent to SAAM is investigated, revealing its significant impact on the microstructure, mechanical properties, and corrosion resistance. Under the high heat input and large width-to-thickness ratio of SAAM, the deposited metal undergoes two remelting processes and multiple reheating processes. This IHT induced nitrogen loss and austenite transformation in the deposited metal, resulting in the formation of interlayer and intralayer zones with different austenite morphology. As the heat input increases, nitrogen loss intensifies and the change of travel speed alters the molten pool morphology, resulting in an increase in cooling rate. These lead to a reduction in austenite content, reaching its lowest value of 63.7 % at the heat input of 2.0 kJ/mm. Subsequently, further increases in heat input result in an increase in austenite content. The yield strength of these components is all higher than the 2205 DSS hot-rolled plates. The pitting corrosion resistance of these components decreases as heat input increases, but remains superior to that of 2205 DSS hot-rolled plates.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118885"},"PeriodicalIF":6.7,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143911567","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":"Effects of a new dual-beam oscillating laser welding technique for aluminum alloy joints: Microstructure, properties, and formation mechanism","authors":"Libo Wang ,&nbsp;Tianyu Xu ,&nbsp;Zhengwu Zhu ,&nbsp;Lin Zhang ,&nbsp;Gaoyang Mi ,&nbsp;Xiuquan Ma","doi":"10.1016/j.jmatprotec.2025.118883","DOIUrl":"10.1016/j.jmatprotec.2025.118883","url":null,"abstract":"<div><div>To optimize the welding process and joint performance of laser-welded aluminum alloys, a novel dual-beam oscillating laser welding technique was employed in this study. Specifically, by adjusting the power ratio of the composite beams and integrating the temperature field simulation, an intrinsic relationship was established among the composite beam process, microstructure, and joint performance. The results indicated that the primary laser beam ensured the welding efficiency and molten pool stability. The oscillation of the auxiliary laser achieved an orderly agitation within the molten pool, collectively refining the grains, destabilizing the grain growth, and establishing new orientations. Such a disruption led to the formation of fragmented fine grains with large grain misorientation angles and high geometrically necessary dislocation densities, as well as regulated temperature gradients in the central region and tiny equiaxed grains with dispersed orientations. Moreover, the power ratio between the primary and auxiliary beams was identified as a critical factor affecting the strength and ductility of the weld. A low power ratio induced keyhole instability, increased defects, and reduced joint performance, whereas a balanced power ratio refined the microstructure and enhanced the joint strength. With an optimal ratio of 950 W (primary) to 450 W (auxiliary), consistent penetration and stable internal oscillations were achieved, thereby improving the overall weld quality.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118883"},"PeriodicalIF":6.7,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143903871","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":"Mechanism of high efficiency self-rotating grinding with low surface and subsurface damage in different oriented single-crystal diamond","authors":"Yongkang Xin ,&nbsp;Jing Lu ,&nbsp;Yueqin Wu ,&nbsp;Xipeng Xu","doi":"10.1016/j.jmatprotec.2025.118882","DOIUrl":"10.1016/j.jmatprotec.2025.118882","url":null,"abstract":"<div><div>Single-crystal diamond (SCD) machining faces significant challenges due to its extreme hardness and anisotropic cleavage behavior. Understanding different oriented SCD material removal behavior is crucial for achieving high-quality and efficient processing. This study presents an efficient self-rotating mechanical grinding method for processing (100), (110) and (111) SCD planes. By tailoring processing parameters to the crystallographic traits, material removal rate exceeding 54.86 μm/h are achieved for different crystal planes. Under the optimized parameters, the surface roughness (Sa) for the (100) plane is below 0.6 nm, with no subsurface damage observed. Through multiscale characterization (TEM/SEM/XPS/Raman) and molecular dynamics (MD) simulations, we reveal that subsurface damage across all planes originates from (111) cleavage, yet manifests differently: (100) planes cleavage along &lt; 110 &gt; directions, (110) planes cleavage along both &lt; 110 &gt; and orthogonal &lt; 112 &gt; /&lt; 1–12 &gt; directions, and (111) planes exhibit horizontal peeling combined with 60°-tilted cleavages. This study clarifies the deformation and damage mechanisms of diamond crystals during ultraprecision machining, which is crucial for achieving efficient and high-precision manufacturing of diamond components.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118882"},"PeriodicalIF":6.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898492","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":"Selection of a better strip for feeding into high-alloy stainless steel 654SMO: A promising technology to improve solidification structure","authors":"Shucai Zhang ,&nbsp;Yifeng Geng ,&nbsp;Huabing Li ,&nbsp;Ximin Zang ,&nbsp;Shengcheng An ,&nbsp;Zhouhua Jiang ,&nbsp;Hao Feng ,&nbsp;Hongchun Zhu ,&nbsp;Pengchong Lu","doi":"10.1016/j.jmatprotec.2025.118879","DOIUrl":"10.1016/j.jmatprotec.2025.118879","url":null,"abstract":"<div><div>Strip composition is a crucial parameter in feeding strip technology because it affects the improvement of the solidification structure; however, there is limited research on this topic. In this study, different strips were fed into 654SMO molten steel, and their influence on the solidification structure was investigated. The results indicated that the effectiveness of the feeding strip depended on its composition and melting point. The 316 L strip with a higher melting point did not melt completely. Feeding 654SMO strip slightly improved the dendritic structure, while feeding 904 L strip significantly expanded the equiaxed zone, refined the dendrites, reduced central Mo segregation, and inhibited σ-phase precipitation. The following mechanisms were revealed. The melting strip produced floating dendrites that acted as nucleation particles. The 654SMO strip and floating dendrites melted quickly, offering a limited refining effect on the dendritic structure. By contrast, the higher melting-point 904 L strip exhibited a longer melting time, and the 904 L floating dendrites survived and proliferated better, thereby markedly improving the dendritic structure. Moreover, feeding the 904 L strip resulted in stronger abilities to inhibit the columnar grain growth and Mo-rich interface movement, discretize and refine Mo segregation regions, and shorten the solidification time. Moreover, the 904 L strip with lower Mo content (4.38 wt%) diluted the central Mo content. All these roles significantly reduced central Mo segregation. Additionally, feeding the 904 L strip could better increase the critical nucleation radius of the σ phase by reducing the driving force and initial formation temperature, and it suppressed the σ-phase growth by slowing Mo diffusion and narrowing the growth space, thereby considerably inhibiting the precipitation of σ phase.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118879"},"PeriodicalIF":6.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898491","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":"Mechanistic design of porous self-lubricating grinding wheels with integrated internal cooling: Role of PMMA and nickel-coated MoS₂ composites in machining enhancement","authors":"Linfeng Zhao ,&nbsp;Ruitao Peng ,&nbsp;Jiangxiong Gao ,&nbsp;Yibo Li ,&nbsp;Min Chen","doi":"10.1016/j.jmatprotec.2025.118877","DOIUrl":"10.1016/j.jmatprotec.2025.118877","url":null,"abstract":"<div><div>This study significantly advances grinding wheel technology by synergistically integrating poly (methyl methacrylate) (PMMA)-induced porosity with nickel-coated molybdenum disulfide (Ni-coated MoS₂) lubrication. This integration addresses the critical trade-off between cooling efficiency and structural durability in grinding nickel-based superalloys. Mechanistic analysis indicates that sintering at 910°C allows nickel to suppress copper-sulfur interfacial embrittlement while promoting titanium carbide (TiC) bonding reinforcement. This process achieves an optimal flexural strength of 72.63 MPa with 5 % PMMA-induced interconnected porosity. The pore network enhances coolant retention, resulting in an 18.6 % reduction in grinding temperature through a combination of internal cooling and lubricant film dissipation. Tribological optimization at 6 % Ni-coated MoS₂ content reduces friction coefficients by 22.7 % under a 100 N load due to lattice distortion effects, while also mitigating abrasive adhesion through controlled solid lubricant release. Comparative grinding trials demonstrate transformative performance: surface roughness decreases by 30.45 % as porous channels retain grinding debris, thereby suppressing three-body abrasion. Additionally, compressive residual stresses increase twofold due to reduced thermal gradients. Crucially, the self-sharpening mechanism extends wheel longevity by maintaining the integrity of abrasive protrusions compared to conventional wheels, as validated by reduced microcracking and spalling observed in post-test microscopy. These advancements establish a material-process paradigm in which controlled porosity generation synchronizes thermomechanical stress management with tribological regulation, achieving simultaneous improvements in surface quality, thermal control, and grinding wheel lifespan for machining applications.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118877"},"PeriodicalIF":6.7,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891359","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":"Effect of activated flux GTAW with AlCoCrFeNi2.1 eutectic high entropy alloy interlayer on microstructure and mechanical properties of dissimilar P91/304 L steel joints","authors":"Tushar Sonar ,&nbsp;Mikhail Ivanov ,&nbsp;Igor Shcherbakov ,&nbsp;Artem Okulov ,&nbsp;Nataliya Shaburova ,&nbsp;Kun Liu ,&nbsp;Emiliya Khasanova ,&nbsp;Pavel Samoilovskikh","doi":"10.1016/j.jmatprotec.2025.118873","DOIUrl":"10.1016/j.jmatprotec.2025.118873","url":null,"abstract":"<div><div>In this study, the effect of activated flux gas tungsten arc welding (GTAW) with AlCoCrFeNi_2.1 eutectic high entropy alloy interlayer on the microstructure and mechanical properties of dissimilar P91/304 L steel joints was studied and the results were compared with the joints welded using the traditional multi-pass GTAW with Inconel 82 filler for its validity in practical applications. The higher overall heat input in multi-pass GTAW and lower solubility of strengthening elements in completely austenitic weld metal deteriorated the mechanical properties of joints. The eutectic high-entropy alloy interlayer imparted a high-entropy effect to the weld metal, resulting in increased mixing entropy and sluggish diffusion behavior. This led to better mixing of the weld metal and a functionally graded structure with minimized unmixed zones, lower carbon migration and reduced peak hardness at the weld metal interface. The flux-assisted arc constriction and reversal of the Marangoni convection effect in activated flux GTAW enabled deeper penetration with lower heat input in two passes compared to the traditional approach. The increased cobalt content (1.36 wt%) in the weld metal suppressed the delta ferrite formation and imparted grain refinement by promoting secondary phase precipitation at the grain boundaries and strengthening the weld metal. The lower heat input in activated flux GTAW with higher nickel and cobalt content in eutectic high entropy alloy interlayer tailored a refined dual phase austenitic-martensitic microstructure with finer discrete secondary phases in weld metal resulting in superior mechanical properties compared to the traditionally welded joints in as-welded state. Thereby eliminates post-weld heat treatment.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118873"},"PeriodicalIF":6.7,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906738","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":"Content effects of in-situ synthesis TiC for grain refinement, porosity suppression and performance enhancement in wire arc additive manufactured Al-Cu alloy","authors":"Wenjun Zhang ,&nbsp;Hao Yi ,&nbsp;Haiqin He ,&nbsp;Huajun Cao","doi":"10.1016/j.jmatprotec.2025.118875","DOIUrl":"10.1016/j.jmatprotec.2025.118875","url":null,"abstract":"<div><div>In wire arc additive manufactured (WAAM) Al-Cu alloys, coarse microstructure and porosity defects have long been critical factors limiting their performance. Fortunately, recent studies have shown that incorporating ceramic particles into additively manufactured components can effectively mitigate these issues. However, developing composite materials in WAAM remains a challenge. Hence, this study successfully fabricated Al-Cu alloy wire with varying TiC content (0.6, 1.2, 2.0 wt%) using an in-situ molten salt reaction method and systematically investigated its enhancement mechanisms on WAAM Al-Cu alloy. The results reveal that TiC addition significantly refines the grain structure, reduces porosity, and enhances mechanical properties. Notably, the alloy containing 1.2 wt% TiC exhibited the best overall properties, achieving a yield strength of 127.5 MPa, an ultimate tensile strength of 311.1 MPa, and an elongation of 12.4 %. Mechanistic analysis reveals that the grain refinement was primarily attributed to enhanced heterogeneous nucleation and the effective inhibition of grain boundary migration. The strengthening mechanisms were dominated by three dominant mechanisms: (i) grain refinement strengthening via the Hall-Petch effect induced by TiC particles, (ii) Orowan strengthening resulting from the dispersion of rigid TiC particles within the matrix, and (iii) Load-bearing strengthening enabled by robust interfacial bonding between TiC particles and the matrix. Furthermore, the improvement in ductility was mainly attributed to porosity reduction, a full columnar-to-equiaxed transition (CET), refined grain structures, and the formation of uniformly distributed fine precipitates. This study highlights the critical role of ceramic particle (TiC) content in optimizing WAAM Al-Cu alloy, offering valuable insights for designing and manufacturing of high-performance large-scale aluminum alloy components.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118875"},"PeriodicalIF":6.7,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891345","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":"Construction and application of a multi-field coupling model for evaluating the hot tearing susceptibility of magnesium alloys under rotating magnetic field","authors":"Shengwei Bai ,&nbsp;Feng Wang ,&nbsp;Xudong Du ,&nbsp;Zhi Wang ,&nbsp;Le Zhou ,&nbsp;Pingli Mao ,&nbsp;Ziqi Wei ,&nbsp;Jinwei Li","doi":"10.1016/j.jmatprotec.2025.118878","DOIUrl":"10.1016/j.jmatprotec.2025.118878","url":null,"abstract":"<div><div>Herein, a comprehensive 3D hot tearing testing model that coupled with transient electromagnetic force, fluid flow, heat transfer and solidification was constructed to quantify the multi-physical field coupling effects during the solidification process of magnesium alloys under rotating magnetic field, which are difficult to measure in experiments. The Mg-4Zn-1.5Ca-0.3Zr alloy was selected as the research object. The accuracy of the model was verified through experiments and theoretical calculations, and the hot tearing mechanism and crack arresting mechanism of magnesium alloys under the action of rotating magnetic field were revealed. The results show that the improvement of the hot tearing resistance of the alloy and the alleviation of stress/strain concentration are the main inducing factors for the reduction of the hot tearing susceptibility of magnesium alloys under the action of rotating magnetic field. Meanwhile, the optimized feeding channel improved the feeding efficiency of magnesium alloys, thereby enhancing their crack arresting ability. In addition, the application of rotating magnetic field reduced the solidification strain of the casting. This work has important practical significance for optimizing the parameters of electromagnetic casting and realizing the production of high-quality magnesium alloy castings. It is expected to provide strong theoretical support and technical guidance for the actual production in related fields.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118878"},"PeriodicalIF":6.7,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898486","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":"Effects of carbon nanotubes on high-quality bonding of W and CuCrZr","authors":"Zhang Liu ,&nbsp;Yuanyuan Chen ,&nbsp;Jianbo Zhang ,&nbsp;Huan Song ,&nbsp;Chenxi Liu ,&nbsp;Yuan Huang ,&nbsp;Zumin Wang","doi":"10.1016/j.jmatprotec.2025.118876","DOIUrl":"10.1016/j.jmatprotec.2025.118876","url":null,"abstract":"<div><div>Confronting the extreme working conditions of plasma facing components, carbon nanotubes (CNTs) were introduced into the bonding of W and CuCrZr alloys by employing a Cu-CNTs interlayer to obtain the joints with excellent thermal and mechanical properties. The bonding process includes Cu-CNTs co-deposition on the surface of W substrate, annealing of Cu-CNTs composite coating, and diffusion bonding with the CuCrZr alloy. The morphological evolutions of Cu-CNTs composite coating and the interface structure of the W/Cu-CNTs/CuCrZr alloy joint were studied by scanning electron microscopy, energy-dispersive spectroscopy, and high-resolution transmission electron microscopy. The Cu-CNTs composite coating was continuous after co-deposition and annealing, and CNTs were uniformly mixed in the coating without significant entanglement. By exploiting the intrinsic strength of individual CNTs, a high shear strength (202 MPa) of the W/Cu-CNTs/CuCrZr alloy joint was obtained through the load transfer effect. The thermal conductivity of the joint increased with temperature in the range of 260–280 W/(m·K), which are about 12 % higher than that of the direct-bonded W/CuCrZr alloy joints. The thermal properties of the W/Cu-CNTs/CuCrZr alloy joints were enhanced due to the reduced thermal mismatch between W and Cu-CNTs interlayer and the thermal conductive network constructed at the interface. This enhancement was achieved by taking advantage of the high thermal conductivity, extremely low coefficient of thermal expansion, and large aspect ratio of the CNTs. The developed bonding process of the W/Cu-CNTs/CuCrZr alloy joint provides an effective support for plasma-facing components in future fusion reactors.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118876"},"PeriodicalIF":6.7,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143891358","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":"Laser-solid interaction and energy accumulation in melt ejection formation during T2 copper oscillation laser welding","authors":"Hao Dong,&nbsp;Yan Cai ,&nbsp;Wucheng Li,&nbsp;Weidong Mu","doi":"10.1016/j.jmatprotec.2025.118874","DOIUrl":"10.1016/j.jmatprotec.2025.118874","url":null,"abstract":"<div><div>The phenomenon of melt ejection during pure copper laser welding exhibits the characteristics of randomness, accidentality, and abruptness. However, the current understanding of this mechanism cannot be used to conduct a detailed analysis of its random and sudden occurrence. Laser oscillations create a constantly changing environment for the laser, keyhole, and molten pool. In this study, a detailed analysis of the formation and development mechanisms of melt ejection was conducted under different laser-oscillation profiles and frequencies. Based on process observations and a self-designed energy and keyhole distortion calculation model, it was found that the random interaction between the laser and solid base metal contributed significantly to the sudden formation of the molten pool by transferring the heat accumulation zone to the rear bottom of the keyhole, which created an abnormal keyhole bulge. This was caused by the very low absorption rate of the solid surface of the T2 copper. The oscillation trajectory of the laser spot changed the frequency and time span when the laser moved near the liquid–solid boundary, as well as the heat input rate at different positions in the molten pool, resulting in a difference in stability with different oscillation strategies. Based on these results, we hypothesized that the formation of melt ejections is closely related to the random contact of a fluctuating keyhole with a highly reflective solid interface. Severe melt ejection was caused by the continuous accumulation of laser energy. This hypothesis led to a better understanding of the instabilities during the laser welding of highly reflective materials and can be applied to analyze most cases where melt ejection occurs.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"340 ","pages":"Article 118874"},"PeriodicalIF":6.7,"publicationDate":"2025-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143894943","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}