Additive manufacturing最新文献

{"title":"Identifying melt pool behavior in ceramics PBF-LB via operando synchrotron tomographic microscopy and high-fidelity process modeling","authors":"A. Muther ,&nbsp;M.G. Makowska ,&nbsp;Z.L. Zhang ,&nbsp;F. Verga ,&nbsp;F. Marone ,&nbsp;N. Garrivier ,&nbsp;A. Cretton ,&nbsp;S. Van Petegem ,&nbsp;M. Bambach ,&nbsp;M. Afrasiabi","doi":"10.1016/j.addma.2025.104756","DOIUrl":"10.1016/j.addma.2025.104756","url":null,"abstract":"<div><div>Recent advancements in high-fidelity process simulations have significantly enhanced the understanding of melt pool behavior during laser-based powder bed fusion (PBF-LB) of metals. However, for ceramics, their unique material properties and complex thermophysical behavior present significant challenges in developing detailed models that effectively complement limited experimental observations. In this work, we integrate operando synchrotron X-ray tomographic microscopy with computational fluid dynamics-discrete element method (CFD-DEM) simulations to investigate the melt pool dynamics of alumina during PBF-LB. In-situ observations reveal a shallow and wide melt pool, distinct from that of metals. This behavior is linked to alumina’s low thermal conductivity, high laser absorption, and negative surface tension gradients, as confirmed through high-fidelity process simulations. Key mechanisms identified include limited heat penetration, enhanced surface-oriented convection, and surface vortices driven by heat exchange with the surrounding gas environment. The influence of laser power and scanning speed on melt pool geometry is systematically analyzed, leading to the first virtual process map and parameter windows for stable PBF-LB of alumina. These findings provide critical insights for optimizing process parameters and advancing ceramic additive manufacturing.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"103 ","pages":"Article 104756"},"PeriodicalIF":10.3,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143760753","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":"Dual-head multi-photon polymerization 3D printing for parallel additive manufacturing organic/inorganic materials in optics","authors":"Zhihan Hong ,&nbsp;Zheng Zhang ,&nbsp;Ruilin You ,&nbsp;Jiabin Chen ,&nbsp;Shaobai Li ,&nbsp;Yihan Wang ,&nbsp;Yuanyuan Sun ,&nbsp;Bofan Song ,&nbsp;Zhongying Ji ,&nbsp;Douglas A. Loy ,&nbsp;Rongguang Liang","doi":"10.1016/j.addma.2025.104772","DOIUrl":"10.1016/j.addma.2025.104772","url":null,"abstract":"<div><div>Rapid 3D laser printing based on two-photon polymerization (TPP) is a promising technique for fabricating high-resolution structures, but its scalability is often hindered by challenges in parallelization and material versatility. In this study, we present a high-precision, multi-head 3D printing system that integrates advanced optical and material control to address these limitations. By employing a dual-head setup with independent focal length adjustments and paired linear polarizers, our system enables simultaneous multi-material printing and rapid iteration of fabrication parameters, significantly enhancing prototyping efficiency. We demonstrated this system's versatility by successfully fabricating diverse microstructures, and compatible with organic and inorganic components. The system can achieve a minimum feature size of sub-100 nm and the highest printing speeds of 20 mm/s with a numerical aperture (NA) of 1.3 or 0.8, balancing precision and efficiency for industrial-scale applications. Additionally, its capability to perform multi-parameter, full-field-of-view additive manufacturing facilitates a wide range of design possibilities. The potential of this technique is further illustrated through two optical applications: an 8 × 8 convex lens array and diffractive optics for high-resolution holography. The lenses exhibit exceptional surface quality and uniformity with a roughness of less than 4 nm and a peak-to-valley surface deviation is around 200 nm, while the diffractive optics achieve sub-wavelength feature resolution, demonstrating the system’s suitability for advanced optical component manufacturing. This study advances the state of additive manufacturing by addressing key challenges in parallelization, scalability, and material diversity.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"103 ","pages":"Article 104772"},"PeriodicalIF":10.3,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746947","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":"Fabricable stochastic periodic porous microstructures: A Wang cube and Gaussian kernel approach","authors":"Lihao Tian ,&nbsp;Zhongren Wang ,&nbsp;Xiaokang Liu ,&nbsp;Kaifeng Tian ,&nbsp;Andrei Sharf ,&nbsp;Lin Lu","doi":"10.1016/j.addma.2025.104739","DOIUrl":"10.1016/j.addma.2025.104739","url":null,"abstract":"<div><div>Stochastic porous structures, characterized by randomly distributed voids within solid materials, are prevalent in natural systems such as geological formations, biological tissues, and ecosystems. These structures play crucial roles in processes like nutrient transport and water retention, making them a key focus of interdisciplinary research. Traditional design methods for stochastic porous structures often require detailed modeling of the entire structure, leading to high computational costs. To alleviate this, periodic microstructures are commonly used to fill target regions with repetitive units. However, generating large-scale stochastic porous structures that combine smooth connectivity with global randomness using periodic units remains a significant challenge. This paper presents a novel approach for generating periodic stochastic porous microstructures based on Wang tile rules. The proposed method employs a parameterized generative model with a dual-layer structure, incorporating 27 types of periodic periphery configurations and internal pore-tunnel structures formed from randomly distributed Gaussian kernels. This design balances stochasticity with boundary constraints. Simulations and experiments validate the proposed approach, showing that the resulting stochastic porous microstructures exhibit distinct deformation patterns and superior energy absorption compared to periodic microstructures.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"103 ","pages":"Article 104739"},"PeriodicalIF":10.3,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739480","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":"Optimizing dimensional accuracy in two-photon polymerization: Influence of energy dose and proximity effects on sub-micrometric fiber structures","authors":"Ianis Drobecq ,&nbsp;Claire Bigot ,&nbsp;Olivier Soppera ,&nbsp;Laurent Malaquin ,&nbsp;Bastien Venzac","doi":"10.1016/j.addma.2025.104735","DOIUrl":"10.1016/j.addma.2025.104735","url":null,"abstract":"<div><div>Two-photon polymerization (2PP) is a powerful technology for achieving sub-micrometric precision in additive manufacturing, enabling the fabrication of 3D fibrillar structures with sub-micrometric fibers. This study provides an extensive study of the parameters that influence the dimensional accuracy of suspended beams, such as energy dose and proximity effects between the surrounding supportive structures and the fibers. Through systematic characterization of these parameters, we analyze the impact of spatial confinement on fiber width, height, and structural stability. Our results reveal that beyond conventional parameters like energy dose, long-range proximity effects induced by oxygen depletion and diffusion significantly influence final feature dimensions. These findings provide insights into optimizing 2PP for high-resolution, reproducible structures, advancing its application in fields where nanoscale precision is essential, such as tissue engineering and photonics.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"103 ","pages":"Article 104735"},"PeriodicalIF":10.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Operando synchrotron X-ray analysis of melt pool dynamics in an Al-Sn immiscible alloy","authors":"Ahmad Zafari ,&nbsp;Sai Pratyush Akula ,&nbsp;Mogeng Li ,&nbsp;Akane Wakai ,&nbsp;Ashlee Gabourel ,&nbsp;Samuel J. Clark ,&nbsp;Kamel Fezzaa ,&nbsp;Ian Gibson ,&nbsp;Atieh Moridi","doi":"10.1016/j.addma.2025.104754","DOIUrl":"10.1016/j.addma.2025.104754","url":null,"abstract":"<div><div>The melt flow in an Al-50vol% Sn immiscible alloy, produced by single-track laser melting of Al and Sn elemental powders, was studied in real time. High-speed synchrotron X-ray imaging was used to track the movements of Al and Sn liquids, and also to examine elemental distributions in the laser tracks, complimented by electron microscopy after solidification. Key aspects, including melt pool geometry, keyhole instability, and flow dynamics (flow pattern and velocity), were examined using digital image analysis. Relatively deeper melt pools formed at 400 W and 300 mm/s exhibited greater stability, with smooth surfaces, consistent outward flow, and minor vortices near the keyhole. In contrast, shallower pools produced at higher scanning speeds (&gt;500 mm/s) demonstrated greater instability with increased surface waviness, and stronger velocity fluctuations, leading to numerous micro-vortices and increased Al-Sn heterogeneity. Velocity scale estimations, supported by experimental observations, examined the roles of vapour pressure, Marangoni effect, buoyancy, inertial, and surface tension forces in the flow. The results revealed that vapour pressure and mechanical waves dominated at high scanning speeds (shallow pools), while Marangoni forces were equally significant in deep pools at lower speeds (300 mm/s). Buoyancy was found to have minimal impact in both cases. Furthermore, the interaction between inertial and surface tension forces played a critical role in determining the degree of waviness of the pools’ surfaces. These findings offer valuable insights into melt pool dynamics during laser processing of immiscible alloys and other metallic systems using elemental powders, and provide guidance for developing high-fidelity computational fluid dynamics models.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"103 ","pages":"Article 104754"},"PeriodicalIF":10.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing laser cladding stability: Defects and schlieren-based analytics during L-DED","authors":"Benedikt Brandau ,&nbsp;Rico Hemschik ,&nbsp;João Paulo Sousa ,&nbsp;Frank Brueckner ,&nbsp;Alexander F.H. Kaplan","doi":"10.1016/j.addma.2025.104758","DOIUrl":"10.1016/j.addma.2025.104758","url":null,"abstract":"<div><div>A schlieren system, adapted for Laser Directed Energy Deposition, was used to monitor and analyze the process zone under various conditions, including deliberate contamination and parameter limits. This approach enabled the identification and correlation of process-induced defects with schlieren phenomena. Events and zones were characterized and qualitative categorized to validate schlieren monitoring as a diagnostic tool. Notably, a highly active and spatially confined schlieren formation was consistently observed above the melt pool. Using a tailored schlieren optical setup and simulations, schlieren patterns were linked to refractive index changes in process gases, enabling quantitative analysis. The refractive index within the hot gas dome over the molten pool was observed to range from 1.00000712 to 1.00875126, with fluctuation speeds reaching up to 210 m/s. As a result, a model was developed to describe the impact of refractive index dynamics on the performance of coaxial monitoring systems in laser processes. A case study using an exemplary imaging monitoring system demonstrated that schlieren phenomena can cause wavelength-dependent lateral geometric shifts of up to 228 µm, significantly affecting the accuracy of object-based monitoring outcomes. The findings offer critical insights into the complex interplay between refractive index variations and monitoring results, paving the way for refined monitoring strategies that enhance reliability and precision in laser cladding applications.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"103 ","pages":"Article 104758"},"PeriodicalIF":10.3,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-situ multi-eye monitoring of melt pool temperature field in laser additive manufacturing by light field camera","authors":"Xiuhua Li ,&nbsp;Hui Li ,&nbsp;Xuefeng Chen ,&nbsp;Shengnan Shen ,&nbsp;Guodong Zhang ,&nbsp;Huiliang Wei ,&nbsp;Yaowu Hu ,&nbsp;Zhongwei Li ,&nbsp;Linmao Dai","doi":"10.1016/j.addma.2025.104747","DOIUrl":"10.1016/j.addma.2025.104747","url":null,"abstract":"<div><div>Laser direct energy deposition (LDED) and laser powder bed fusion (LPBF) are two typical metal laser-based additive manufacturing (AM) processes used in critical fields such as aerospace and aviation. However, the stability of their part quality remains challenging. The temperature of the melt pool during the AM process significantly influences the quality of the manufactured parts. Therefore, breakthroughs in in-situ monitoring technology for high-temperature, small-area melt pools keep an urgent need. To address this challenge, this paper proposes a multi-eye monitoring method using a light field (LF) camera for in-situ melt pool temperature field monitoring. Initially, a LF sub-aperture Bayer model (LFSBM) is established to extract melt pool images at red, green, and blue (<em>R</em>, <em>G</em>, and <em>B</em>) wavelengths. By calibrating the LF camera’s relative spectral response ratio using the blackbody furnace, the melt pool’s temperature field is derived based on dual-wavelength theory from two images at <em>R</em>, <em>G</em>, and <em>B</em> channels. Linear fitting of the relative spectral response ratio for channel combinations of <em>B</em> and <em>G</em>, <em>R</em> and <em>B</em>, and <em>R</em> and <em>G</em> yielded root mean square errors of 76.34 K, 62.24 K, and 78.66 K, respectively. The mean error for maximum temperature was verified to be 1.03 %, and less than 3 % for temperature filed at temperatures of 2973.15 K, 3073.15 K, and 3273.15 K by the blackbody furnace. The influence of coaxial system of LPBF on wavelength intensity was calibrated. The contour error between the temperature map and the blackbody furnace was found to be less than 1.4 %. Experiments were conducted on high-entropy alloy, and Ti6Al4V alloys manufactured by both LDED and LPBF equipment, and evolution of length, width, and maximum temperature were analyzed. The proposed method simplifies the measurement process and allows for an unlimited temperature range, providing a groundbreaking approach for in-situ melt pool temperature monitoring during the AM process.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104747"},"PeriodicalIF":10.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687817","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":"In-situ crosslinked nano SiO2 reinforced alginate bio-textile for mitigating plastic shrinkage in 3D printed concrete","authors":"Kailun Xia ,&nbsp;Yuning Chen ,&nbsp;Zedi Zhang ,&nbsp;Wei Wang ,&nbsp;Yu Chen ,&nbsp;Lutao Jia ,&nbsp;Zijian Jia ,&nbsp;Shitao Quan ,&nbsp;Yamei Zhang","doi":"10.1016/j.addma.2025.104753","DOIUrl":"10.1016/j.addma.2025.104753","url":null,"abstract":"<div><div>Absence of formwork leaves 3D printed concrete (3DPC) with rapid water loss and plastic shrinkage. For water preservation, a strategy based on in-situ generated bio-textile film on 3DPC surface is proposed herein. The conception was achieved by adopting nano SiO₂ (NS) reinforced sodium alginate (NSSA) onto 3DPC surface. Triggered by calcium ions on 3DPC surface, in-situ crosslinking of NSSA can generate a water preservation film, where NS serves as reinforcer for film densification. Moreover, through pozzolanic reaction, NS can induce further crosslinking between C-S-H and alginate biopolymer matrix, forming a bio-textile film with enhanced water vapor impermeability, mechanical property and surface adhesion on 3DPC. Within 3 hours and 24 hours after concrete printing, this strategy significantly reduced 3DPC plastic shrinkage by 74 % and 59 %, and preserved water in 3DPC from evaporation by 72.8 % and 75.4 %. This study provides a promising new approach for mitigating plastic shrinkage of 3DPC.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104753"},"PeriodicalIF":10.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704127","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":"Constraint-based form-finding of space trusses for Injection 3D Concrete Printing through Vector-based Graphic Statics","authors":"Yinan Xiao ,&nbsp;Norman Hack ,&nbsp;Harald Kloft ,&nbsp;Dirk Lowke ,&nbsp;Inka Mai ,&nbsp;Pierluigi D’Acunto","doi":"10.1016/j.addma.2025.104751","DOIUrl":"10.1016/j.addma.2025.104751","url":null,"abstract":"<div><div>This paper presents a form-finding approach for Injection 3D Concrete Printing (I3DCP) using Vector-based Graphic Statics (VGS). This approach adopts a top-down strategy, initiating a preliminary global design in the form of a space truss and integrating structural and fabrication constraints specific to I3DCP. A form-dependent self-weight load is applied throughout the form-finding process until the structure achieves static equilibrium. As the current I3DCP setup is mounted on a robotic arm with a stationary base, the feasibility of the designed structure for I3DCP is assessed, ensuring compatibility with the robotic arm’s workspace. Structures exceeding the workspace boundaries are segmented and individually optimised, subject to topological and geometrical constraints. The optimised segments are then merged into a single assembly to complete the process. This approach is demonstrated through the design and construction of a 3-metre-span pedestrian bridge. This prototype is 3D scanned and then analysed via the finite element method to evaluate its mechanical performance.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"103 ","pages":"Article 104751"},"PeriodicalIF":10.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143739658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design and optimization of high stiffness tetrahedral lattice structure","authors":"Peng Zhang ,&nbsp;Fengxi Bai ,&nbsp;Yi Liu ,&nbsp;Yingxin Ma ,&nbsp;Wei Zeng ,&nbsp;Yi-Jun Yang ,&nbsp;Ligang Liu ,&nbsp;Weiming Wang","doi":"10.1016/j.addma.2025.104719","DOIUrl":"10.1016/j.addma.2025.104719","url":null,"abstract":"<div><div>As tetrahedra are well known for their stability and excellent load-bearing capabilities, this work proposes a novel method for designing and optimizing high-stiffness tetrahedral lattice structures. First, the tetrahedral lattice cells with periodic boundary conditions are generated within a unit cubic domain based on a specified number and radii of randomly distributed seed points. By analyzing the printability of the lattice cell, several constraints are introduced to restrict both the number of seed points and their radii within each lattice cell. Next, the relationships among the number of seed points, radii, relative density, Young’s modulus, and anisotropy of the lattice cells are analyzed using the homogenization method. For a given design domain, it is discretized into a hexahedral finite element mesh. A topology optimization formulation is then proposed to optimize the number of seed points and their radii across all finite elements. The seed points are randomly sampled within each finite element according to the optimized number and radius. Finally, a strut-shaped tetrahedral lattice with variable radii is generated based on the seed points and their radii. Additionally, a strategy is introduced to eliminate struts in low-density regions to further enhance structural stiffness. Extensive numerical and physical experiments, along with comparisons, have been conducted to demonstrate the effectiveness of the proposed method.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104719"},"PeriodicalIF":10.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704126","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}