Lindsey B. Bezek , Ryan P. Wilkerson , Jonah L. Chad , Theresa E. Quintana , Brian M. Patterson , Santosh Adhikari , Kwan-Soo Lee
{"title":"Evolution of debinding and sintering of a silica-based ceramic using vat photopolymerization additive manufacturing","authors":"Lindsey B. Bezek , Ryan P. Wilkerson , Jonah L. Chad , Theresa E. Quintana , Brian M. Patterson , Santosh Adhikari , Kwan-Soo Lee","doi":"10.1016/j.addma.2025.104795","DOIUrl":"10.1016/j.addma.2025.104795","url":null,"abstract":"<div><div>One challenge in developing new ceramics for additive manufacturing (AM) is determining a post-process heating strategy (including debinding and sintering) that produces parts with sufficient mechanical strength while mitigating defects and unpredictable shrinkage. In this work, the authors explore how modifying debinding and sintering parameters (e.g., temperatures, hold times, and rates) affects material and mechanical properties of parts fabricated using a commercial silica-based resin and the vat photopolymerization AM process. Parts were qualitatively assessed for effective debinding before being subjected to different sintering conditions. Tradeoffs between time and temperature were observed during both debinding and sintering phases. Strong correlations between thermal schedules and density, shrinkage, porosity, and flexural properties were observed in sintered parts, where increasing sintering temperature, hold time, and rate generally increased density, shrinkage, and flexural strength. Average densities ranged from 1.27 to 2.01 g/cm<sup>3</sup> depending on the selected debinding and sintering strategy. The condition with the highest density, which heated to 1300°C at 300°C/h, yielded the lowest porosity (∼11 %), shrinkage of ∼15 % (XY) and ∼20 % (Z), flexural strength of ∼28 MPa, and flexural strain at break of ∼0.11 %. The novelty of this work is the systematic investigation of the effects of different temperatures, hold times, and ramp rates for both debinding and sintering on density, porosity, shrinkage, and flexural properties in ceramic AM. Fundamental understanding of how post processing affects ceramic AM parts will enable establishment of guidelines on how to strategically select post-process conditions for new ceramics. This knowledge will support predictable part performance and contribute to a framework that expands the applicability of ceramic AM parts for functional applications.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104795"},"PeriodicalIF":10.3,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marwan Haddad , Mathew Cohen , Aslan Bafahm Alamdari , Brian Welk , Kamel Fezzaa , Sarah Wolff
{"title":"Process-structure relationships in laser directed energy deposition of molybdenum powder within a Ti–6Al–4V matrix","authors":"Marwan Haddad , Mathew Cohen , Aslan Bafahm Alamdari , Brian Welk , Kamel Fezzaa , Sarah Wolff","doi":"10.1016/j.addma.2025.104780","DOIUrl":"10.1016/j.addma.2025.104780","url":null,"abstract":"<div><div>Laser directed energy deposition (L-DED) of multi-materials is capable of additively fabricating parts with enhanced properties for biomedical and aerospace applications. This study focuses on the multi-material printing of Ti–6Al–4V (Ti64) and molybdenum (Mo) with L-DED. Alloying Mo with Ti64 improves the high-temperature mechanical properties of Ti64. However, the dynamic and melting behavior of the Mo powder inside the Ti64 matrix and their impact on the L-DED process and the microstructure are still unclear. This study utilizes <em>in situ</em> monitoring techniques, namely high-speed X-ray imaging and infrared imaging, with post-process material characterization techniques to relate the L-DED process of depositing Mo powder into a Ti64 matrix to the final microstructure. Results showed that the motion of Mo powder particles inside the melt pool was governed by the convective fluid flow. The convective fluid flow achieved an overall homogeneous macro-scale chemical composition by influencing the melting behavior of Mo powder particles and contributing to the liquid mixing. The increase in Mo content in Ti64 did not impact the melt pool temperature. Lastly, Mo segregated at the micro-scale near the top surface, and Mo-rich regions were located near unmmelted powder particles in the final build. This work can help improve multi-material applications and verify simulation models for L-DED.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104780"},"PeriodicalIF":10.3,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Samsul Mahmood , Loren Baugh , Seungjong Lee , Nabeel Ahmad , Daniel F. Silva , Alexander Vinel , Jia Liu , Shuai Shao , Nima Shamsaei , Robert L. Jackson , Kyle D. Schulze
{"title":"A comparative analysis of non-destructive surface topography measurement techniques for additively manufactured metal parts","authors":"Samsul Mahmood , Loren Baugh , Seungjong Lee , Nabeel Ahmad , Daniel F. Silva , Alexander Vinel , Jia Liu , Shuai Shao , Nima Shamsaei , Robert L. Jackson , Kyle D. Schulze","doi":"10.1016/j.addma.2025.104791","DOIUrl":"10.1016/j.addma.2025.104791","url":null,"abstract":"<div><div>Surface characterization of additively manufactured specimens is confounded by their intricate geometries and the presence of various features, including asperities, undercuts, and deep, sharp valleys. Despite the need to understand the impact of surface features on many practical applications, there is a lack of consensus regarding the variability inherent in measurement techniques. Here the topography of as-built Ti-6Al-4V specimens is examined through the utilization of four techniques: contact stylus profilometers, white light interferometers, focus variation microscopy, and X-ray computed tomography. Identification of discrepancies across measurement techniques was made possible through qualitative and quantitative analyses of measured surfaces. Conventional surface texture parameters were used to differentiate the methods and provide guidance for effective scan parameters and measurement technique selection.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104791"},"PeriodicalIF":10.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yifan Guo , Shuzhi Xu , Yifan Wang , Jikai Liu , Rafiq Ahmad , Yongsheng Ma
{"title":"DGTO: Derivable geodesics-coupled topology optimization for multi-axis hybrid additive and subtractive manufacturing with curved layer generation","authors":"Yifan Guo , Shuzhi Xu , Yifan Wang , Jikai Liu , Rafiq Ahmad , Yongsheng Ma","doi":"10.1016/j.addma.2025.104786","DOIUrl":"10.1016/j.addma.2025.104786","url":null,"abstract":"<div><div>This paper presents a concurrent optimization model named DGTO (Derivable Geodesics-coupled Topology Optimization), aiming at simultaneously designing the structure, slices, and sequences for multi-axis hybrid additive and subtractive manufacturing. The proposed method involves two variable fields: the density field representing the structure, and the auxiliary variable field for generating geodesic distance-based curved slices for additive manufacturing (AM). A novel heat diffusion equation and Poisson equation-based approach is proposed to generate the curved layers while ensuring all slicing-related information derivable. Additionally, sequence division thresholds are optimized to determine the timings of alternating between AM and subtractive machining (SM) operations. An excellent feature of the proposed sequence division method is that, it eliminates the initial-guess dependency issue, i.e., the quantity of AM-SM alternations has a reducing trend during optimization and converges to the most compact solution. To realize the synchronous optimization and ensure the successful manufacturing, a coupled and differentiable optimization model is established, including a self-support constraint to eliminate the need for support structure, a direction constraint to avoid the collision between the laser head and printing platform, and a curvature constraint to guarantee the layer thickness uniformity. In addition, a collision-free constraint, coupled with the planned sequences, is introduced to prevent cutting tool collision during SM. To validate the proposed method, a number of 2D and 3D numerical examples are studied. The above figure demonstrates one of the results and the associated manufacturing process simulation.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104786"},"PeriodicalIF":10.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kunlong Zhao , Zhijie Ye , Zhenhua Su , Wenxin Cao , Dongmeng Shi , Xiaobin Hao , Sen Zhang , Zhuochao Wang , Xingchun Xu , Jiaqi Zhu
{"title":"A diffusion-controlled kinetic model for binder burnout in a green part fabricated by binder jetting based on the thermal decomposition kinetics of TEG-DMA","authors":"Kunlong Zhao , Zhijie Ye , Zhenhua Su , Wenxin Cao , Dongmeng Shi , Xiaobin Hao , Sen Zhang , Zhuochao Wang , Xingchun Xu , Jiaqi Zhu","doi":"10.1016/j.addma.2025.104793","DOIUrl":"10.1016/j.addma.2025.104793","url":null,"abstract":"<div><div>Thermal debinding is a core process in indirect additive manufacturing processes of metals. Inappropriate debinding methods can introduce impurities into the interior of the formed green part, thus limiting the upper limits of the mechanical, electrical, and thermal properties. However, while binder jetting (BJT) is one of the most popular indirect 3D printing methods, its debinding process has largely been overlooked. This study models and analyzes the thermal debinding process of the binder jetting green part (BJGP) based on the Gaussian multimodal fitting (GMF) method; further, the grayscale-printed green part (g-BJGP) is analyzed for the first time. The results indicate that the GMF model is effective for fitting the thermal decomposition kinetics of the binder, with <em>R</em><sup>2</sup> values of greater than 0.97 under heating rates of 5, 10, and 15 ℃/min. Based on analysis of the thermal debinding model, the maximum monomer content inside the green part during the thermal debinding process of g-BJGP is only 1/10 of that of conventional BJT printing under heating rates of 5, 10, and 15 ℃/min. This suggests that grayscale printing may help BJT become one of the least-polluting indirect molding methods. This study provides a detailed reference for the thermal debinding process of BJGP.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104793"},"PeriodicalIF":10.3,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143838217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the viability of in-situ alloyed Ti-1Fe as a strong and ductile alternative to Ti-6Al-4V for laser-based powder bed fusion","authors":"Jeff Huang , Ammarueda Issariyapat , Shota Kariya , Junko Umeda , Katsuyoshi Kondoh","doi":"10.1016/j.addma.2025.104788","DOIUrl":"10.1016/j.addma.2025.104788","url":null,"abstract":"<div><div>Developments in the additive manufacturing (AM) of titanium have historically centred around the market-leading Ti-6Al-4V alloy, with many studies aimed at adapting the seventy-year-old composition for newer AM processes such as laser-based powder bed fusion (PBF-LB/M). Amongst these studies, PBF-LB/M Ti-6Al-4V is usually shown to be remarkably strong (with gigapascal ultimate tensile strengths) and moderately ductile (if defect free), because of the ultra-fine martensitic α/α’ microstructures produced under the rapid cooling conditions of PBF-LB/M. However, despite these acceptable properties, the use of Ti-6Al-4V in AM fundamentally contradicts the original intention behind the design of this alloy composition, which relies on rare and expensive vanadium solutes to promote α+ β microstructures for good wrought-forming properties. In essence, neither the intended microstructures, nor the intended properties are relevant or compatible with near-net-shape AM processes. Therefore, it seems natural to question the strict adherence to conventional alloys in PBF-LB/M. In search of alternatives, the present study attempts to replicate the microstructures and properties of PBF-LB/M Ti-6Al-4V using the cheaper and leaner composition of Ti-1Fe prepared by in-situ alloying (i.e. from mixed elemental feedstocks). Both fine and coarse Fe particles were investigated to identify optimal feedstock characteristics and build parameters. In homogeneously mixed samples prepared from fine Fe particles at higher energy densities, similar microstructures to Ti-6Al-4V were successfully obtained, with corresponding tensile properties that exceed the performance requirements of ASTM F2924 (950 MPa yield strength, 12 % fracture strain). A theoretical analysis of strengthening mechanisms revealed significant contributions from grain refinement effects, dislocation hardening, and solid solution strengthening by oxygen and nitrogen interstitials. With these findings, we report for the first time the prerequisite conditions for obtaining strong and ductile tensile properties from as-built, in-situ alloyed Ti-1Fe as a potential low-cost alternative to Ti-6Al-4V for PBF-LB/M, and the problems that may occur with sub-optimal processing.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104788"},"PeriodicalIF":10.3,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143842160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Changliang Yao , Shanshan He , Ki-Yong Lee , Kwang-Yong Shin , Do-Sik Shim
{"title":"Microstructural and interfacial characteristics in repair of nickel-aluminum bronze by in-situ synthesis of Cu-Al alloys via directed energy deposition","authors":"Changliang Yao , Shanshan He , Ki-Yong Lee , Kwang-Yong Shin , Do-Sik Shim","doi":"10.1016/j.addma.2025.104787","DOIUrl":"10.1016/j.addma.2025.104787","url":null,"abstract":"<div><div>Directed energy deposition (DED) has demonstrated significant potential for component repair, owing to its flexibility in deposition path and powder feedstock selection. However, research on manufacturing Cu-Al alloys via DED remains limited. This study employed a pre-mixed blend of CuNi2SiCr and Al-Mg-0.7Si powders to synthesize Cu-Al alloys in situ for the DED-based repair of nickel-aluminum bronze (NAB). By varying the mass fraction of the Al-Mg-0.7Si powder (6, 8, 10, and 12 wt%), the effects of aluminum content on the microstructure, hardness, and tensile behavior of the repaired samples were investigated by micro- and nanoscale characterization. The results indicated that all repaired samples were free of obvious defects, such as pores or thermal cracks, and exhibited excellent metallurgical bonding between the repaired area and substrate. The microstructures of samples containing 6 and 8 wt% Al-Mg-0.7Si powder were predominantly <em>α</em> phase while those with 10 and 12 wt% Al exhibited <em>β</em><sub><em>1</em></sub> martensitic twin structures. The samples repaired with 6 wt% Al-Mg-0.7Si powder demonstrated the best tensile properties, with a tensile strength of 624 MPa and elongation of 14.4 %. The tensile properties of the 10 and 12 wt% Al samples were lower owing to the precipitation of the Widmanstätten <em>α</em> phase at the <em>β</em><sub><em>1</em></sub> martensitic grain boundaries. Fracture locations varied across samples, but cracks did not propagate along the repaired interface, suggesting excellent interfacial bonding strength. Additionally, unusual <em>γ</em><sub><em>2</em></sub> phase precipitates were observed in all the samples. This research provides valuable insights into the feasibility of in-situ Cu-Al alloy fabrication via DED for the repair of NAB.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104787"},"PeriodicalIF":10.3,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chao Wang , Zhi Zhao , Zeyu Li , Yingqi Jia , Arvin Ardebili Sharma , Xiaojia Shelly Zhang
{"title":"Direct ink writing of magnetic soft materials with optimized printing path","authors":"Chao Wang , Zhi Zhao , Zeyu Li , Yingqi Jia , Arvin Ardebili Sharma , Xiaojia Shelly Zhang","doi":"10.1016/j.addma.2025.104770","DOIUrl":"10.1016/j.addma.2025.104770","url":null,"abstract":"<div><div>Direct ink writing (DIW) of magnetically responsive soft materials with high remanent magnetization, where a locally applied magnetic field aligns magnetized particles along the printing path, offers transformative potential across diverse applications. However, most existing studies have been confined to the printing of discrete magnetization patterns, which could restrict the functionality of achievable designs and preclude the creation of continuous magnetization distributions. Moreover, there is a lack of effective and automated path-generation methods capable of translating numerical designs with heterogeneous magnetization distributions and complex geometries into precise, manufacturable toolpaths. In this work, we introduce a novel, comprehensive framework that seamlessly integrates optimized design and additive manufacturing of hard-magnetic soft materials, enabling continuous magnetization encoding through the automatically generated printing paths. The framework extend the magneto-active soft material optimization approach to generate printable designs with continuous magnetization while considering manufacturing constraints. We propose an efficient toolpath generation algorithm that maps optimized magnetization directions to continuous printing paths, preserving the optimized topology. We explain the DIW process and experimentally characterize the mechanical and magnetic properties of the fabricated materials. The capabilities of the framework are comprehensively demonstrated through three experimentally validated examples: a magneto-active elevator mechanism, butterfly metasurfaces with complex magnetization distributions encoded by corresponding toolpaths, and a metamaterial design with globally generated toolpaths. These examples showcase the framework’s capability to effectively bridge the gap between design and additive manufacturing. The framework also has the potential for generalization across emerging 3D and 4D printing technologies involving other functional materials, opening new frontiers in the design and manufacturing of intelligent, responsive material systems.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104770"},"PeriodicalIF":10.3,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuze Zhang , Pan Zhang , Tan Cheng , Hui Li , Kai Zhong , Zhongwei Li , Yusheng Shi
{"title":"High precision 3D contour detection for laser powder bed fusion in-process layerwise monitoring using active contours driven by multiple energy","authors":"Yuze Zhang , Pan Zhang , Tan Cheng , Hui Li , Kai Zhong , Zhongwei Li , Yusheng Shi","doi":"10.1016/j.addma.2025.104761","DOIUrl":"10.1016/j.addma.2025.104761","url":null,"abstract":"<div><div>The Laser Powder Bed Fusion (LPBF) process utilizes a layered manufacturing approach, offering significant advantages in the fabrication of complex metal components. A key challenge in the production of high-precision, high-performance parts is the online monitoring of the solidified region in each layer of the powder bed, as well as identifying geometric defects. In this study, a novel approach for contour extraction is proposed, integrating multiple energy terms, including grayscale, entropy, phase difference, and photometric stereo, to drive the evolution of active contours. Various combinations of these energy terms are compared, and the effectiveness of each is validated. The results show that, compared to traditional active contour methods that consider only grayscale energy, the proposed method reduces the mean squared errors by 84.4 %, 61.7 %, and 95.8 % for ring contours, diamond ring contours, and center distances, respectively. These improvements contribute to the development of a quality monitoring and process parameter feedback system based on 3D geometric deviations in the solidified region, thus enhancing the precision and repeatability of LPBF processes.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"105 ","pages":"Article 104761"},"PeriodicalIF":10.3,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143842157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zixiang Li , Boce Xue , Baohua Chang , Shuhe Chang , Zhenyu Liao , Yinan Cui , Changmeng Liu , Dong Du
{"title":"Influence mechanism and visual monitoring of wire deviation in wire-based electron beam directed energy deposition","authors":"Zixiang Li , Boce Xue , Baohua Chang , Shuhe Chang , Zhenyu Liao , Yinan Cui , Changmeng Liu , Dong Du","doi":"10.1016/j.addma.2025.104784","DOIUrl":"10.1016/j.addma.2025.104784","url":null,"abstract":"<div><div>Wire-based electron beam directed energy deposition (DED) is acclaimed for its high deposition efficiency, optimal material utilization, and the ambient conditions of vacuum deposition. Nonetheless, the inherent stresses resulting from wire circular stockpiling, coupled with the thermal-induced deformation, readily lead to the deviation of feeding wire from the molten pool, which drastically impacts the forming quality and stability during the deposition process. Therefore, it is imperative to delve into the influence mechanisms of the wire deviation response and develop the corresponding online monitoring method. In this study, the wire deviation simulation model was originally established, and the experiment method was also combined to reveal the effects of wire deviation on the wire melting process, molten pool dynamics, and the as-printed part morphology. Furthermore, a visual sensing system and corresponding image extraction algorithms were also developed, specifically designed to monitor and analyze this behavior. Results indicate with increasing deviation distance, the wire melting pattern shifts from droplet to liquid bridge mode until it fails to melt. When the deviation distance is on a small-scale, it can cause molten pool liquid outflow (liquid transition mode) and a deviation in the deposition path location (droplet transition mode) despite the existence of obvious reflux behavior. In addition, the monitoring system developed in this study can effectively protect the camera lens from being contaminated by the metal vapor and the issue of unclear wire regions caused by the overexposure of the molten pool. The gray-level co-occurrence matrix was adopted to effectively overcome the issue of unclear boundaries at the wire center, and the texture entropy feature’s noise ratio only increased from 1.0 to 1.3, demonstrating good noise resistance. Based on the developed algorithm, the wire’s deflection distance can be detected with an error below 0.1 mm and a response time under 10 ms. The newly revealed mechanisms and the developed monitoring technologies lay a solid foundation for the subsequent closed-loop control of wire deviation behavior, making a significant enhancement of forming stability and automation level of wire-based DED technology.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"104 ","pages":"Article 104784"},"PeriodicalIF":10.3,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143833463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}