Additive manufacturing最新文献

{"title":"Binder-powder interactions in binder jetting: Binder drying, layer shifting, and inter-layer binding","authors":"Erlei Li,&nbsp;Wentao Yan","doi":"10.1016/j.addma.2025.104951","DOIUrl":"10.1016/j.addma.2025.104951","url":null,"abstract":"<div><div>Binder jet additive manufacturing shows significant potential for cost-effective massive production of complex-shaped parts. However, defects like layer shifting degrade the part quality, hindering its widespread adoption. In this work, a resolved computational fluid dynamics and discrete element method coupling model is developed to investigate the detailed physics in the binder jetting process, including binder drying, layer shifting, and inter-layer binding. Non-uniform temperature distribution of the primitive is caused by the uneven powder layer thickness and inherent heating path from the top to the bottom. The primitive is displaced downwards and forwards under the action of normal and shear forces resulting from the motion of the roller and powder particles above it. Longer drying time enables the binder to be stiffer and further withstand shearing during the spreading of new powder layer. Inter-layer binding is reproduced by simulating two-layer binder jetting process, where the weak binding case shows disconnected binders. The simulation results align well with experimental observations and analytical predictions, accurately capturing powder spattering, liquid spreading behaviour, layer shifting, and droplet penetration dynamics. This study offers comprehensive insight into the fundamental mechanisms of the binding process, and provides guidance for defect mitigation to address current challenges in binder jetting technology.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104951"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144996281","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":"3D photocuring for circuit fabrication: Optimization of UV penetration properties via the morphology of silver particles","authors":"Mei-Ling Yang ,&nbsp;Yi-Tian Yang ,&nbsp;Guo-Xiang Zhou ,&nbsp;Zhi-Hua Yang ,&nbsp;De-Chang Jia ,&nbsp;Yu Zhou","doi":"10.1016/j.addma.2025.104931","DOIUrl":"10.1016/j.addma.2025.104931","url":null,"abstract":"<div><div>Photocuring printing technology is extensively applied in the manufacturing complex structure for electrical components owing to its excellent printing flexibility and efficiency. However, the limited penetration depth of UV photocured silver pastes (UVSPs), resulting from the complex interaction between incident light and conductive fillers, restricts circuit fabrication. In this work, we optimized the selection of flaky silver particles as UVSP fillers instead of the conventional spherical ones by simulating the penetration distribution of incident light in UVSPs with various morphologies through the finite element method. The fluidity, polymerization behavior, and printing properties of the UVSPs were investigated. As a result, flaky particles filled UVSP with the unique light penetration properties can be used for high-precision film printing, and the printing linewidth accuracy can be improved by over 20 μm under the same exposure conditions. Furthermore, the conductive film with flaky particles effectively prevented curling and peeling during low-solid-content sintering and exhibits a good electrical conductivity of 1.26 × 10⁶ S/m. This study provides valuable technical guidance for the rapid preparation of low-cost, high-precision circuit printing using photocuring printing technology, which significantly reducing the manufacturing cost of printed electronic components.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104931"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144880393","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":"Multi-wavelength centrifugal processing enables 3D printing of functionally graded medical devices: Construction and validation of mechanically tunable orthodontic aligners","authors":"Xincheng Yin ,&nbsp;Qian Zhang ,&nbsp;Yuqi Li ,&nbsp;Daxin Wu ,&nbsp;Siyu Wang ,&nbsp;Yanzhe Fu ,&nbsp;Siyang Wei ,&nbsp;Na Li ,&nbsp;Xun Chen ,&nbsp;Xiang Ding ,&nbsp;Chao Wang ,&nbsp;Yubo Fan ,&nbsp;Jianmin Han ,&nbsp;Jiebo Li","doi":"10.1016/j.addma.2025.104930","DOIUrl":"10.1016/j.addma.2025.104930","url":null,"abstract":"<div><div>Functionally Graded Materials (FGMs) have gained substantial attention in biomedical device development, particularly for creating functionally adaptive solutions. In recent years, grayscale vat photopolymerization 3D printing has emerged as a promising technology for FGMs fabrication owing to its advantages of high efficiency and precision. However, the residual unreacted monomers in grayscale printing components have brought a large amount of toxicity, becoming a bottleneck restricting their application in biomedical fields. This study proposes a multi-wavelength stepwise curing strategy that integrates wavelength-selective photoabsorber (PA) into the resin, using clear orthodontic aligners as a platform, to achieve a highly polymerized surface state while enabling gradient mechanical properties. Based on the integration of light field simulation and photopolymerization kinetics, a mathematical model was developed to predict the degree of conversion (DoC) distribution in multi-layer printing. The printed aligners demonstrated validated biocompatibility, with <em>in vitro</em> experiments showing that grayscale modulation effectively reduced orthodontic forces on non-targeted teeth while resisting stress relaxation during 7-day continuous monitoring. Furthermore, a centrifugation-based post processing method was developed to effectively eliminate surface layer steps and reduce bacterial adhesion. This process is compatible with the majority of current photopolymer resin systems and provides a technical framework for developing advanced functional medical devices.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104930"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144864433","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":"Preventing microcracks between directed energy deposited Hastelloy X and IN792 substrate by adding IN625 buffer layer","authors":"Ye Chan Sung ,&nbsp;Beom Jun Kim ,&nbsp;Gideok Park ,&nbsp;Seong-Moon Seo ,&nbsp;Hyungsoo Lee ,&nbsp;Hyoung Seop Kim ,&nbsp;Jung Gi Kim","doi":"10.1016/j.addma.2025.104947","DOIUrl":"10.1016/j.addma.2025.104947","url":null,"abstract":"<div><div>Recently, laser-based additive manufacturing (AM) has emerged as a promising method for repairing complex-shaped components. Although small heat-affected zones and high degrees of freedom expand the processing window for AM, microcrack initiation can occur depending on the combination of parent materials. In particular, frequent microcracking has been observed in additively manufactured Hastelloy X (HX) despite its extensive use in hot components for gas turbine systems. To mitigate this issue, Inconel (IN) 625 was deposited as a buffer layer before the deposition of HX to prevent elemental diffusion between HX and IN792 substrate. Consequently, the IN625 buffer layer reduced the W migration from the IN792 substrate to the HX deposit layer, suppressing segregation at the grain boundaries. In addition, the enhanced Nb content in the HX deposit layer, owing to the high Nb content in the IN625 buffer layer, stabilized the primary carbides in the interdendritic region. By combining these two effects, microcracking was suppressed when the IN625 buffer layer was placed between the IN792 substrate and the HX deposit layer. The suppression of microcracks near the interface delayed crack initiation and propagation during tensile tests, resulting in greater elongation with the IN625 buffer layer compared to the specimens without it. This finding highlights the critical role of selecting the deposit layers in influencing microcrack initiation in partially repaired components, suggesting that designing a sequence of deposit layers can be an effective strategy for AM without extensive alloying modifications for additive manufacturing.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104947"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917712","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":"An efficient and uncertainty-aware reinforcement learning framework for quality assurance in extrusion additive manufacturing","authors":"Xiaohan Li,&nbsp;Sebastian W. Pattinson","doi":"10.1016/j.addma.2025.104912","DOIUrl":"10.1016/j.addma.2025.104912","url":null,"abstract":"<div><div>Defects in extrusion additive manufacturing remain common despite its prevalent use. While numerous AI-based quality assurance approaches have been proposed, the dynamic nature of printing processes often causes deterministic models to lose robustness and, in some cases, fail entirely in new or slightly altered environments. This work introduces an agent that adjusts flow rate and temperature in real-time to optimize control while addressing bottlenecks in training efficiency and uncertainty management. A vision-based uncertainty quantification module generates probabilistic distributions from classified extrusion states, which are integrated with a deep Q-learning controller. While the underlying networks are deterministic, the evolving distributions introduce adaptability to the decision-making process. The controller learns optimal asynchronous actions in a simulation calibrated to vision accuracy and trained with progressively tightened elliptically shaped rewards that account for parameter coupling. With zero-shot learning, the agent bridges the sim-to-real gap and reliably corrects 21 tests across three extrusion error levels—slight, moderate, and severe—with average convergence steps of <span><math><mrow><mn>40</mn><mo>.</mo><mn>67</mn><mo>±</mo><mn>17</mn><mo>.</mo><mn>41</mn></mrow></math></span>, <span><math><mrow><mn>44</mn><mo>.</mo><mn>00</mn><mo>±</mo><mn>13</mn><mo>.</mo><mn>56</mn></mrow></math></span>, and <span><math><mrow><mn>49</mn><mo>.</mo><mn>11</mn><mo>±</mo><mn>17</mn><mo>.</mo><mn>91</mn></mrow></math></span>, respectively. The modest increase in convergence steps and stable standard deviations across error levels underscore the controller’s effectiveness and robustness. Beyond extrusion, this scalable framework supports practical AI-driven quality assurance across various additive manufacturing.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104912"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144893267","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":"Spatiotemporal monitoring and control for foam additive manufacturing processes of thermoplastics","authors":"Zhaowei Zhou,&nbsp;Kaicheng Ruan,&nbsp;Donghua Zhao,&nbsp;Xuguang Xu,&nbsp;Ziwen Chen,&nbsp;Yi Xiong","doi":"10.1016/j.addma.2025.104949","DOIUrl":"10.1016/j.addma.2025.104949","url":null,"abstract":"<div><div>Foam Additive Manufacturing (Foam-AM) offers a novel approach to fabricating architected structures with tunable density by leveraging in-situ foaming. However, precise control of the foaming process remains challenging due to the complex interplay of multiple process parameters. This complexity has limited the broader adoption of Foam-AM in applications such as packaging, protective gear, automotive components, and beyond. To address these challenges, this study proposes a novel spatial-temporal monitoring and control method using a multi-sensor platform to optimize the performance and geometry of Foam-AM. The platform integrates a thermal camera and positioning encoders to monitor the temperature field and speed distribution, identifying bead interference and speed variations as the primary causes of foaming defects. Additionally, a line laser profiler is used to measure sample’s spatial information, complemented by extruder encoder data for in-situ density estimation. This in-situ approach facilitates high-throughput data acquisition, forming the basis for a process-performance model developed using Invertible Neural Networks (INN). Leveraging the INN model, two major advancements are achieved: (1) off-line control strategies effectively minimize bead interference, ensuring consistent density and geometric precision; and (2) localized foaming defects, especially in regions with rapid speed changes, are accurately identified and addressed through real-time parameter adjustments, significantly improving overall print quality.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104949"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932611","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":"High speed thermal imaging and modeling of laser powder bed fusion manufactured WC–Ni cemented carbides","authors":"Guadalupe Quirarte,&nbsp;Alexander J. Myers,&nbsp;Alexander Gourley,&nbsp;Craig M. Weeks,&nbsp;B. Reeja-Jayan,&nbsp;Jack Beuth,&nbsp;Jonathan A. Malen","doi":"10.1016/j.addma.2025.104913","DOIUrl":"10.1016/j.addma.2025.104913","url":null,"abstract":"<div><div>Cemented carbides such as cemented tungsten carbide (WC) are known for their use in resilient wear-resistant applications where hardness and thermal stability are imperative. They are composed of carbide particles embedded in a metal binder. Laser Powder Bed Fusion (L-PBF) is a favorable method to form cemented carbides into complex geometries, but composites pose unique challenges relative to metals typically processed by L-PBF. Resolving the melt pool temperature distributions in L-PBF is key to understanding the underlying physics of the fusion process. Using a two-color thermal imaging method, melt pool thermal maps of WC_0.83-Ni_0.17 were captured with linear energy densities ranging from 500–1750 J/m with and without powder. WC_0.83-Ni_0.17 melt pools exhibit temperatures above 4000 K, which can lead to the generation of other WC phases. Compared to more common L-PBF materials such as 316L stainless steel (SS), WC_0.83-Ni_0.17 melt pools reach higher temperatures. Our direct measurements find that the thermal conductivity of WC_0.83-Ni_0.17 is 30 W/m-K at 300 K, which is higher than the thermal conductivity of 316L SS and suggests that other heat transfer limitations must cause the elevated melt pool temperatures. A FLOW-3D CFD model based on the composite properties was compared to both the melt pool centerline temperatures and width measurements of the samples fabricated by L-PBF. The simulations indicate that specifying the onset of fluidity is key to reproducing the high temperatures observed experimentally. Although Ni has a melting point of 1728 K, the simulations do not match experiments unless the onset of fluidity is set at the melting point of WC (3143 K). Within FLOW-3D, the onset of fluidity is controlled by the critical solid fraction, which is a uniquely important parameter for simulating composite materials.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104913"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144852416","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":"A novel dual-phase Bayesian estimation and multi-task learning method for process optimization for reducing lack-of-fusion defects during laser powder bed fusion","authors":"Yusheng Chen ,&nbsp;Dongdong Gu ,&nbsp;Keyu Shi ,&nbsp;Yanze Li ,&nbsp;Wenxin Chen","doi":"10.1016/j.addma.2025.104926","DOIUrl":"10.1016/j.addma.2025.104926","url":null,"abstract":"<div><div>In metal additive manufacturing, lack-of-fusion is one of the most critical porosity defects. Its complex formation mechanism makes the modeling process highly challenging. While existing researches have focused on high-fidelity simulations, high-performance predictions and process map based on single-track scenarios, the actual printing process requires consideration of the interlapping and stacking of multi-layer and multi-track melt pools. This significantly increases the computational cost of high-fidelity simulations and the computational error of traditional analytical models. In this study, we developed the dual-phase Bayesian estimation and multi-task learning (Dual-BE&amp;ML) method. This approach innovatively “teaches” the machine learning models to account for system error and uncertainty by incorporating physical laws. It also demonstrates enhanced fitting capabilities for the melt pool width. Using a set of dimensionless numbers, we constructed a sensitivity map for inter-layer lack-of-fusion porosity in laser powder bed fusion of 316 L stainless steel. This allows us to accurately avoid process regions prone to inter-layer lack-of-fusion porosity during the process optimization. The results show that when the ratio of melt pool depth to layer thickness exceeds 1.62 and the ratio of hatch spacing to melt pool width is less than 0.76, the inter-layer lack-of-fusion porosity disappears. This not only confirms the reliability of our approach but also provides important guidance for accelerating process optimization and product design.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104926"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144852418","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":"Combinatorial mapping of high-temperature oxidation in SS316L–IN718 dissimilar alloys printed by laser-directed energy deposition","authors":"Mustafa Kas ,&nbsp;Oguzhan Yilmaz ,&nbsp;Wei Xiong","doi":"10.1016/j.addma.2025.104932","DOIUrl":"10.1016/j.addma.2025.104932","url":null,"abstract":"<div><div>Functionally graded materials (FGMs) enable the investigation of oxidation behavior across variable compositions, allowing efficient evaluation of how gradual changes in alloy content influence high-temperature performance. In this study, stainless steel 316 L (SS316L) and Inconel 718 (IN718) were combined to produce both a nine-layer gradient FGM and a bimetallic sample via laser-directed energy deposition (LDED). After prolonged high-temperature exposure to 500 h at 850 °C in air, the effects of composition and interface design on oxidation resistance were systematically examined using localized analysis of oxide scale formation and microstructural evolution. A clear improvement in oxidation resistance and oxide adhesion was observed above a threshold of 30 wt.% IN718 in the FGM with gradient composition. At the same time, the abrupt transition in bimetallic print did not result in severe spallation due to interdiffusion at the interface. The results further reveal that an intermediate IN718 region (10–20 wt.%) is prone to solidification cracks that promote internal oxidation, and that, in the IN718-rich areas (70–100 wt.%), microhardness decreases after oxidation due to the dissolution of strengthening phases (γ'/γ'') and grain coarsening. This combinatorial and composition-sensitive approach, utilizing FGMs, offers valuable new insights for designing oxidation-resistant materials for high-temperature applications.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104932"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144864434","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":"Novel 3D printed BaTiO3-based ceramics with high PTC effect via vat photopolymerization and vacuum infiltration","authors":"Wen Zheng ,&nbsp;Xi Chen ,&nbsp;Bingxiao Xue ,&nbsp;Tianwen Dong ,&nbsp;Kaixin Chen ,&nbsp;Wei Luo ,&nbsp;Qiuyun Fu","doi":"10.1016/j.addma.2025.104945","DOIUrl":"10.1016/j.addma.2025.104945","url":null,"abstract":"<div><div>Structural modification is a feasible and effective method to improve the heating efficiency and uniformity of BaTiO₃-based ceramics with positive temperature coefficient (PTC) of resistance. However, modifying three-dimensional (3D) structures by traditional manufacturing methods is very challenging due to the inhomogeneous mixing of raw materials and high mold dependency. Additionally, the realization of complex structures using emerging vat photopolymerization (VPP) technology is limited by the poor curing properties of leaded PTC ceramic slurry. Herein, this study presents an innovative approach of combining VPP technology with vacuum infiltration (VI) process for fabricating high-performance PTC ceramics. Notably, the introduction of soluble starch significantly enhances the curing depth and printability of PTC ceramic slurry. Meanwhile, silica nanoparticles in silica sols are infiltrated into 3D printed green bodies to improve the electrical properties of PTC ceramics. At optimal soluble starch content and silica concentration, a lower room temperature resistivity (ρ=207 Ω·cm) and a higher temperature coefficient of resistance (α_0–15=25.14 %/℃) are obtained in printed PTC ceramics compared to dry pressed PTC ceramics (ρ=301 Ω·cm, α_0–15=19.32 %/℃). Therefore, this work provides a novel technological strategy for fabricating high-performance PTC ceramics with desirable structures and can promote the wide application of PTC heating elements.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"110 ","pages":"Article 104945"},"PeriodicalIF":11.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144996417","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}