Journal of Materials Processing Technology最新文献

{"title":"Bi-directional scanning strategies for residual stress management by tailoring microstructural evolution in directed energy deposition of 9Cr-1Mo steel","authors":"Amritesh Kumar ,&nbsp;Swarup Bag ,&nbsp;V.C. Srivastava","doi":"10.1016/j.jmatprotec.2025.118906","DOIUrl":"10.1016/j.jmatprotec.2025.118906","url":null,"abstract":"<div><div>The transient heating and cooling cycles in arc-based directed energy deposition (DED) processes play the critical role in defining the microstructure and mechanical performance of nuclear-grade steel (9Cr-1Mo) deposition. The current study establishes a comprehensive framework that advances the underlining physics of thermal gradients, phase transformations, and residual stress evolution during the DED process. By combining finite element (FE) simulation and microstructural analysis, the study demonstrates a ∼17 % reduction in tensile residual stress along the build direction following optimized bi-directional scanning strategies. Thermodynamic modeling using the Scheil-Gulliver approach elucidates the formation of key phases, such as δ-ferrite, martensite, and precipitates (M₂₃C₆ and MX), under non-equilibrium conditions inherent to DED process. These findings reveal that non-equilibrium cooling suppresses δ-phase formation, promotes a martensitic matrix, and tailors cellular or dendritic morphologies decisive for mechanical performance. Transmission electron microscopy (TEM) analysis highlights that bi-directional scanning refines martensitic laths, reduces dislocation tangles, and promotes uniform carbide precipitation, significantly enhance microstructural stability and material performance. The current work not only shows the ways of mitigating Type IV cracking through stress reduction and microstructural control but also provides a transferable framework for tailoring deposition strategies in ferritic/martensitic steels and other high-performance materials suitable for industrial applications.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118906"},"PeriodicalIF":6.7,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144108053","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":"High-resolution copper micropatterning on flexible substrates via laser-assisted surface activation","authors":"Zhaoyan Li ,&nbsp;Yuhang Luo ,&nbsp;Xiaozhu Xie ,&nbsp;Jiageng Yang ,&nbsp;Huanhuan Zhuang ,&nbsp;Yajun Huang","doi":"10.1016/j.jmatprotec.2025.118901","DOIUrl":"10.1016/j.jmatprotec.2025.118901","url":null,"abstract":"<div><div>High-performance conductive metal circuits are essential in the modern electronics industry. Additive manufacturing techniques offer significant advantages over traditional photolithography (subtractive methods) in terms of simplicity, cost-effectiveness, and scalability. While various printing techniques have been explored, most are limited by minimum feature sizes in the tens of microns and require high-temperature post-processing to enhance the performance of functional materials. Here, a facile, efficient, and versatile additive manufacturing strategy is proposed for creating high-resolution copper patterns via laser-assisted selective metal deposition. This technique employs an ultrafast UV laser to selectively irradiate areas where copper patterns will be formed, inducing photochemical modifications. The irradiated regions are then seeded and subjected to ECP, resulting in a metal layer deposited on catalytic seed crystals. The copper coating achieved exhibits excellent conductivity (1.77 μΩ·cm) and adhesion (5B, ASTM), comparable to bulk copper. This approach enables the fabrication of high-precision miniature circuits with copper patterns as narrow as 4 μm on various untreated rigid and flexible substrates, accommodating diverse and complex design requirements. The approach is demonstrated for patterning metal interconnects in flexible electronics, including touch screens and thermal heaters, advancing the next generation of printed electronics.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118901"},"PeriodicalIF":6.7,"publicationDate":"2025-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144139691","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":"Thermal history-tailored microstructure, microhardness, and tensile properties in heterogeneous double-wire arc directed energy deposited martensitic stainless steel","authors":"Weiyao Tian ,&nbsp;Haoyu Kong ,&nbsp;Qi Sun ,&nbsp;Yibo Liu ,&nbsp;Chunyu Wang ,&nbsp;Qingjie Sun","doi":"10.1016/j.jmatprotec.2025.118904","DOIUrl":"10.1016/j.jmatprotec.2025.118904","url":null,"abstract":"<div><div>Martensitic stainless steel (MSS) is renowned for its exceptional performance. However, current researches on the additive manufacturing of MSS rely on pre-alloyed materials with fixed compositions, limiting the flexibility. This study utilized a heterogeneous double-wire arc directed energy deposition (DED) technique to in situ fabricate MSS wall structures, employing a hybrid feedstock of 55 % ER2209 (duplex stainless steel) and 45 % ER70-G (low-alloy steel). Two distinct inter-layer cooling strategies were implemented. Under shortened inter-layer cooling intervals, pronounced thermal accumulation elevated inter-layer temperatures above the martensite start transformation (M_s) temperature, delaying phase transformation until post-deposition cooling. This regime produced coarser lath martensite with retained δ-ferrite, resulting in higher strength and hardness but poorer plasticity. Conversely, prolonged cooling durations allowed inter-layer temperatures to approach room temperature, facilitating thermal cycling-induced microstructure-property transformation. This transitioned initial lath martensite/δ-ferrite to a tempered martensite-austenite dual-phase architecture and promoted microstructural refinement. Consequently, improvement in elongation was achieved despite moderate reductions in strength and hardness. Furthermore, this investigation elucidated the intrinsic correlation between thermal history and phase transformation mechanisms through a synergistic combination of experiment and simulation, reproducing the evolution of microstructure during each deposition. This work demonstrates the feasibility of fabricating MSS using common heterogeneous welding wires and clarifies the regulation mechanism of thermal history on the in situ fabricated MSS. This study establishes a transferable theoretical framework applicable to diverse material systems in DED research.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118904"},"PeriodicalIF":6.7,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144124203","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":"Eliminating bottom defects in medium-thickness titanium alloy joints by improving material flow via a new dynamic rotation supporting friction stir welding method","authors":"S. Cong ,&nbsp;L.H. Wu ,&nbsp;Z.W. Wang ,&nbsp;N. Li ,&nbsp;F.F. Wang ,&nbsp;X. Zhang ,&nbsp;X.C. Du ,&nbsp;P. Xue ,&nbsp;F.C. Liu ,&nbsp;D.R. Ni ,&nbsp;B.L. Xiao ,&nbsp;Z.Y. Ma","doi":"10.1016/j.jmatprotec.2025.118900","DOIUrl":"10.1016/j.jmatprotec.2025.118900","url":null,"abstract":"<div><div>It is generally difficult to eliminate bottom defects during friction stir welding (FSW) of medium-thick/thick Ti alloy plates, since there still lacks of deep understanding of the material flow mechanism influencing the formation of bottom defects. In this study, different variant FSW methods were conducted to 7 mm Ti-6Al-4V alloy plates, and the oxide tracking method was utilized to study the material flow mechanism. During conventional dynamic supporting FSW, the main reason for bottom defects was related to cavities formed in the bottom at the initial stage and not filling in time during welding. A new dynamic rotation supporting FSW (DRSFSW) method with a movable bottom rotating shoulder instead of the traditional backing plate was first time proposed to eliminate bottom defects in Ti alloy joints. The essential cause of eliminating bottom defects was associated with the fact that the bottom rotating shoulder added an extra reverse material flow pattern to avoid initial defects, following by fuller material flow and faster material filling rates during the welding. The high-temperature phase reconstruction method showed that colonies with high orientation consistency was largely promoted to form by more sufficient deformation, fully dynamic recrystallisation and fewer nucleation sites after adding the extra reverse material flow pattern during DRSFSW. The joint strength reached 971 MPa, with a joint strength coefficient of 96.8 %. This study uncovers the material flow pattern for FSW with different bottom states and provides a new method to enlarge the welding window and improve the quality of FSW Ti alloy joints.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118900"},"PeriodicalIF":6.7,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144089203","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":"Chatter-free milling of aerospace thin-walled parts","authors":"Xuebing Li ,&nbsp;Jing Ni ,&nbsp;Xianli Liu ,&nbsp;Caixu Yue ,&nbsp;Shuming Yang ,&nbsp;Xia Ji ,&nbsp;Steven Y. Liang ,&nbsp;Lihui Wang","doi":"10.1016/j.jmatprotec.2025.118903","DOIUrl":"10.1016/j.jmatprotec.2025.118903","url":null,"abstract":"<div><div>The milling process of aerospace thin-walled parts requires extremely high geometric precision and surface quality, as these factors significantly influence aircraft performance and operational reliability. Milling chatter not only severely compromises machined surface integrity and accelerates tool wear, but also induces catastrophic production failures and significant economic losses. Over recent decades, the machining community has dedicated substantial efforts to investigating milling chatter mechanisms and developing corresponding control strategies. Remarkable progress has been made in terms of chatter stability prediction, online condition monitoring, and active/passive suppression techniques, with the ultimate objective of achieving chatter-free milling operations. However, compared with conventional milling processes,</div><div>thin-walled part machining presents distinctive challenges due to their inherent characteristics such as low structural rigidity, poor machinability, and complex dynamics involved during milling operations (including time-varying behaviors, modal coupling, and position-dependent effects). These combined factors pose significant obstacles to effective chatter control. This paper consequently concentrates on recent advancements in milling chatter research for aerospace thin-walled parts: (i) Establishing dynamic models that accurately characterize actual milling processes by incorporating force-induced deformation and tool wear effects; integrating dynamic parameter updating techniques with probabilistic stability lobe diagram (SLD) solution approaches to provide risk-aware chatter prediction results. (ii) Leveraging multi-signal fusion and statistical analysis/artificial intelligence (AI) to realize real-time chatter condition monitoring; exploring effective measures to improve monitoring model generalization capabilities under limited sample sizes and variable operational conditions. (iii) Evaluating passive and active chatter suppression strategies systematically, combined with digital twin technology to enable seamless integration of chatter monitoring, suppression, and process optimization. (iv) Discussing milling chatter-induced part surface/sub-surface defects, with related indexes to quantify the effect of chatter marks on surface integrity. Through critical analysis of cutting-edge research and industrial applications, we further evaluate current research limitations and present promising future directions. These include innovations in chatter mechanism modeling, uncertainty quantification, physics-AI hybrid methodologies, edge-cloud-fog monitoring systems, novel materials development, metaverse-enabled human-computer interfaces, and collaborative control technologies of shape accuracy-surface integrity.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118903"},"PeriodicalIF":6.7,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144071770","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":"Regulating electric field with electrode rotation to enhance surface quality in sinking electrochemical milling of groove","authors":"Xiaolei Chen ,&nbsp;Zixian Deng ,&nbsp;Juchen Zhang ,&nbsp;Zhisen Ye ,&nbsp;Yongjun Zhang","doi":"10.1016/j.jmatprotec.2025.118898","DOIUrl":"10.1016/j.jmatprotec.2025.118898","url":null,"abstract":"<div><div>This research introduces a method of regulating electric field with electrode rotation to enhance surface quality in sinking electrochemical milling of groove. A tube electrode with partial insulation on sidewall is employed, when the exposed part of tube electrode’s sidewall faces the machining area, the power supply is activated for material dissolution and then switched off if the exposed part rotates to already machined area, reducing stray corrosion. Based on the correlation between electrode rotation angle and power supply state within one full rotation, four regulation modes were developed. In mode 1, power supply keeps switch-on during a full rotation of electrode, and the on-time ratio is 100 % (360°/360°). The ratio is 50 % (180°/360°) in mode 2, as the power supply is switched on in half of rotation. It’s 40 % (144°/360°) in mode 3, and 30 % (108°/360°) in mode 4. Simulations revealed that the already machined area suffered from pulse current density with peak gradually decreased in mode 1, exposing it to low current density. This issue was effectively eliminated in other modes. Experiments showed a significant reduction of corrosion pits on already machined surface from mode 1 to mode 4, with surface roughness decreased from 2.78 μm to 1 μm. Oxygen content in the already machined area also decreased. Further analysis indicated that uneven breakdown of oxide films at low current density led to poor surface quality of already machined area, and mode 4 effectively prevented this, enhancing surface quality. This research advances sinking electrochemical milling for high-quality manufacturing.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118898"},"PeriodicalIF":6.7,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144070089","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":"Exploring of the effects of thermal ablation and plasma expansion on structure formation during ultrafast laser processing of Ti6Al4V alloy","authors":"Guangzhi He ,&nbsp;Jiaqun Li ,&nbsp;Haoze Han ,&nbsp;Jianfeng Yan ,&nbsp;Jiawang Xie ,&nbsp;Ma Luo ,&nbsp;Yuzhi Zhao ,&nbsp;Yanhai Cheng ,&nbsp;Ming Qiao","doi":"10.1016/j.jmatprotec.2025.118902","DOIUrl":"10.1016/j.jmatprotec.2025.118902","url":null,"abstract":"<div><div>Ultrafast laser processing has opened possibilities for surface modification of Ti6Al4V alloy, endowing them with enhanced and controllable properties. The interaction between ultrafast laser and metals is a complex process with energy transfer, material state evolution and mechanical dynamic at different spatial and temporal scales. However, the knowledge about material response of metals is still necessary to explore due to the complex ablation processes. Here, we study metal structure response induced by ultrafast laser thermo-mechanical ablation in a multi-scale perspective of micro-to-nanometer and femto-to-nanosecond region. Recast surface structure, dense crack, and nano oxidation layer are observed due to the thermal ablation after ultrafast laser processing. Hydrodynamic disturbance indued by plasma expansion contributes to the outwards ejection and recasting of molten materials to form extrusion craters and self-organized grooves. The mechanical effect induced by plasma expansion reconstructs internal structures with grain refinement and dislocation multiplication. Surface hardness is increased by multi-scale structure modification due to the thermo-mechanical ablation. Our work provides insights into the thermo-mechanical effects incurred by ultrafast laser pulse, which benefits the optimal laser conditions for precision processing, micro/nano fabrication, and surface engineering applications.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118902"},"PeriodicalIF":6.7,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143948448","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":"pH-driven interfacial bond dynamics enable high-efficiency low-damage polishing of fused silica with CeO2 based slurries","authors":"Fukun Li ,&nbsp;Yang Bai ,&nbsp;HaiXiang Hu ,&nbsp;Guanbo Qiao ,&nbsp;Lingzhong Li ,&nbsp;Feng Zhang ,&nbsp;Xuejun Zhang","doi":"10.1016/j.jmatprotec.2025.118896","DOIUrl":"10.1016/j.jmatprotec.2025.118896","url":null,"abstract":"<div><div>Achieving atomic-level surface integrity while maintaining a high material removal rate (MRR) remains a fundamental challenge in the polishing of fused silica due to its high hardness and brittleness. This study establishes a novel mechanistic framework for understanding how pH-driven interfacial bond dynamics govern chemo-mechanical polishing processes. By integrating multiscale experimental characterization (XPS, FTIR, Raman spectroscopy) with ReaxFF molecular dynamics simulations, we demonstrate for the first time that the dynamic equilibrium between the formation and rupture of Ce–O–Si interfacial bonds directly control removal efficiency and surface quality. Alkaline conditions enhance OH^– activity, facilitating Si–O bond hydrolysis and stable Ce–O–Si linkage formation, resulting in the highest MRR (397.6 nm/min). Acidic environments promote citrate-mediated Ce³⁺ complexation and nanocluster dispersion, enabling a rolling mechanism that achieves ultra-smooth surfaces (Sq = 0.086 nm). In contrast, neutral pH conditions suffer from PEG adsorption blocking active sites, leading to a 62 % reduction in MRR relative to alkaline systems. A 12.2-fold increase in MRR compared to SiO₂ abrasives (32.67 nm/min) confirms that chemical interfacial dynamics, rather than mechanical abrasion alone, are critical to material removal. This fundamental advancement provides a broadly generalizable theoretical basis for designing efficient, low-damage precision polishing processes across oxide-based optical materials and beyond.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118896"},"PeriodicalIF":6.7,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143948447","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":"The evolution mechanism and strengthening mechanism of the second phase in pulsed laser welded joints of rare earth magnesium alloy","authors":"Xiaobin Zhang ,&nbsp;Bangfu Zhang ,&nbsp;Tingqu Li ,&nbsp;Yunbo Qian ,&nbsp;Xiaoxu Zheng ,&nbsp;Weifeng Xie","doi":"10.1016/j.jmatprotec.2025.118899","DOIUrl":"10.1016/j.jmatprotec.2025.118899","url":null,"abstract":"<div><div>Magnesium alloy welded joints face significant challenges in terms of high tensile properties, and behind these high tensile properties lies fundamental research on microstructure. In this paper, aiming at the problem of the second phase that is difficult to control during the welding process of magnesium alloys, pulsed laser welding was successfully carried out on Mg-5Al-2Gd-0.5Mn magnesium alloy plates. The combined technology of zonal Scanning electron microscope (SEM), transmission electron microscope (TEM) and electron backscatter diffraction (EBSD) was adopted, aiming to study the mechanism and strengthening mechanism of the entire process of the evolution of the second phase from the nanometer scale to the micrometer scale during the welding process. So as to achieve the purpose of regulating the generation of the second phase to improve the performance of the joint. The research results show that within the crystal, there are mainly circular sub-micron-sized Al₂Gd phases and rod-shaped Al₂Gd phases combined with self-phase. At the same time, there are also a small amount of post-generated ones combined with Al₈Mn₄Gd phases and Al₂Gd phases. At the grain boundary (GB), there are mainly nano-scale Al₈Mn₄Gd phases, along with a small amount of nano-scale Mg₁₇Al₁₂ and Al₁₂Mn phases. There are also clusters of sub-micron polycrystalline phases newly formed by combining Al₈Mn₄Gd phases with other phases. The average hardness and ultimate tensile strength (UTS) of the joint are 68.9 HV and 261.7 MPa, respectively. Because during the formation process of the rare earth (RE) phase with similar orientation characteristics to Mg, a large number of dislocations are absorbed, reducing the degree of plastic deformation of the material. In the magnesium alloy, the Mg₁₇Al₁₂ phase is replaced by the RE phase that is stuck within the grains and at the GB. The RE phase forms a conconsistent phase boundary with the Mg matrix, hindering the movement of dislocations. The contribution rate of the second phase strengthening is 47.7 %. At the same time, the formation of the RE phase promotes the formation of GB. The grains were refined, the contribution rate of grain boundary strengthening is 37.6 %, and the RE phase significantly improved the mechanical properties of the joint. The research result provides the necessary basic theory for regulating the complex second phase of magnesium alloys to improve the mechanical properties of magnesium alloy joints.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118899"},"PeriodicalIF":6.7,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941836","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":"Sonotrode design and spatial-temporal configuration strategy of ultrasonic vibration for aluminum/steel resistance spot welding","authors":"Baokai Ren ,&nbsp;Kang Zhou ,&nbsp;Ping Yao ,&nbsp;Gang Wang ,&nbsp;Wenxiao Yu","doi":"10.1016/j.jmatprotec.2025.118897","DOIUrl":"10.1016/j.jmatprotec.2025.118897","url":null,"abstract":"<div><div>Exploring the rational and effective spatial-temporal configuration strategy of ultrasonic vibration for the ultrasonic longitudinal vibration-assisted resistance spot welding (UA-RSW) is significant important for the manufacture of high-strength and reliable aluminum/steel welded joints. However, systematic sonotrode design methods, spatial configurations (electrode-sonotrode geometric coupling, vibration application position), and temporal configuration (vibration duration) have been severely neglected in related work. This work proposes a systematic method for sonotrode design in UA-RSW process, achieving frequency matching between the ultrasonic excitation system and sonotrode. The effects of ultrasonic vibration application position and electrode-sonotrode combination on the macro-morphology and mechanical performance of aluminum/steel UA-RSW joints were systematically investigated. Experimental results revealed that directing ultrasonic vibrations toward the steel sheet increased energy transfer efficiency, which enhances sheet melting rate and thermal conductivity, ultimately increasing aluminum nugget diameters. Further studies demonstrated that the application of a radius-truncated electrode-sonotrode combination promoted radial Joule heat transfer and inhibited thickness reduction of the aluminum alloy sheet, achieving an average tensile-shear strength of 6.14 kN. The study on ultrasonic temporal strategy revealed that extending ultrasonic vibration duration from 350 ms to 550 ms effectively promoted grain refinement in both the aluminum melting zone and the heat-affected zone with the average grain size at the center region of the aluminum melting zone reduced by 54.3 %. Additionally, the regulation effect of ultrasonic vibration on the joint microstructure was significantly diminished after the solidification of the aluminum alloy. The experimental results demonstrated that ultrasonic vibration delayed by 100 ms post-current removal can effectively balance the IMC layer growth and grain distribution. These systematic investigations can provide both theoretical guidance and practical methodology for aluminum/steel UA-RSW in automotive applications.</div></div>","PeriodicalId":367,"journal":{"name":"Journal of Materials Processing Technology","volume":"341 ","pages":"Article 118897"},"PeriodicalIF":6.7,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143948446","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}