Additive manufacturing最新文献

{"title":"A detailed study of pre-heating effects in electron beam melting powder bed fusion process","authors":"E. Landau ,&nbsp;Y.I. Ganor ,&nbsp;D. Braun ,&nbsp;M. Strantza ,&nbsp;M.J. Matthews ,&nbsp;E. Tiferet ,&nbsp;G. Ziskind","doi":"10.1016/j.addma.2025.104656","DOIUrl":"10.1016/j.addma.2025.104656","url":null,"abstract":"<div><div>Metal-based additive manufacturing processes, such as powder bed fusion with electron beam (PBF-EB) process, also referred to as electron beam melting (EBM), can produce high-density parts with minimal residual stresses due to the uniform and coherent preheating of the powder bed. However, understanding and controlling the multiple stages of preheating is required to enable the production of high-quality, consistent parts of various materials. This work presents a large-scale, multi-layer, three-dimensional numerical analysis focused on studying the preheating stages for predicting thermal history during the PBF-EB process. The model follows a continuous multi-stage cyclic process, that incorporates all the main stages of the PBF-EB process for 316 L stainless steel. This includes the gradual deposition of a new powder layer, the first and second preheating levels of the powder bed, and the energy deposition during melting (excluding the actual melt-pool behavior simulation). The model employs an adaptive time-scaling approach that automatically adjusts the energy deposition for each solution time-increment. This allows for localized changes in time-resolution over an otherwise computationally expensive multi-layer procedure. The material property variations are also taken into account, with an emphasis on the subtle irreversible changes in powder effective thermal conductivity after the two requisite preheating stages of the powder bed. This effect is studied using simplified conductivity models from the literature for partially sintered powder, validated by a dedicated experiment and numerical simulation. The large-scale model is then used to estimate the actual temperatures during first and second preheating levels for 316 L steel, which is not yet fully supported commercially for PBF-EB. Model predictions are corroborated by experiments, using and analyzing IR images, taken at the completion of each layer by the machine’s built-in infrared camera. The current model also incorporates a qualitative assessment for the effects of conductivity change during pre-heating, as well as evaluates the applicability of the time-scaling approach.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104656"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137444","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":"Ti2AlNb microlattices via 3D ink-extrusion printing and sintering of precursor powders","authors":"Ya-Chu Hsu,&nbsp;David C. Dunand","doi":"10.1016/j.addma.2025.104673","DOIUrl":"10.1016/j.addma.2025.104673","url":null,"abstract":"<div><div>Microlattices are 3D-extruded with inks containing a blend of precursor Ti + Nb + TiAl₃ powders, and their struts are then densified through a series of heat treatments to eliminate organic binder, sinter porosity, and achieve compositional Ti₂AlNb homogeneity. The phase evolution of an as-printed filament (representative of a microlattice strut) is examined using <em>in-situ</em> X-ray diffraction, revealing a series of steps: (i) TiAl₃ decomposition, starting at 710 °C and ending at 780 °C, to form TiAl; (ii) Nb and Al interdiffusion, initiating at 820 °C, accompanied by the formation of Nb₂Al and Nb₃Al phases; (iii) the α→β Ti phase transformation and (iv) Ti₃Al formation, starting at 870 °C. Fully-homogenized Ti₂AlNb microstructures with low residual porosity, comprising a B2 matrix and two types of α₂ and O (orthorhombic) secondary phases, are achieved after sintering at 1300 °C for 5 h. Under compression at 1000 °C, microlattices with struts ∼400 µm in diameter show a good combination of yield strength (138 MPa) and ductility (48 %, with no catastrophic failure). Because of their low density (∼3 g/cm³) and high strength at high temperatures, Ti₂AlNb microlattices exhibit a specific strength higher than existing Ni- and Co-based superalloy microlattices above 900 °C. Finally, a complex Ti₂AlNb prototype heat exchanger is created <em>via</em> layer-by-layer ink-extrusion and sintering.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104673"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137894","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":"Structured, sintered, and rastered strategies for fluid wicking in additively manufactured heat pipes","authors":"Cameron Noe ,&nbsp;Swapnil Morankar ,&nbsp;Alexander S. Rattner ,&nbsp;Alexander Potts ,&nbsp;Zachary Goode ,&nbsp;Tatiana El Dannaoui ,&nbsp;John R. Sherbondy ,&nbsp;Nikhilesh Chawla ,&nbsp;William Sixel ,&nbsp;Sven Bilén ,&nbsp;Stephen Lynch ,&nbsp;Chad Westover ,&nbsp;Dhruv Bhate","doi":"10.1016/j.addma.2025.104669","DOIUrl":"10.1016/j.addma.2025.104669","url":null,"abstract":"<div><div>This work compares three different strategies for creating wicking structures with Laser Powder Bed Fusion (LPBF) for use in additively manufactured monolithic heat pipes: (i) structured wicks, fabricated with intentionally designed lattice geometries, (ii) sintered wicks, created by partially melting and fusing the metal powder used in the LPBF manufacturing processes, and (iii) rastered wicks, created by modifying the laser raster infill grid parameters to generate fluid flow paths. The study was performed in three phases. Phase I examined wick fluid absorption, porosity, volumetric energy density, and wick manufacturability for a broad range of production parameters. A subset of promising wick production approaches was identified for fluid rate-of-rise characterization in Phase II. One high performing wick production approach was selected for each strategy for detailed characterization in Phase III. In this last phase, the wick candidates were studied through X-ray microtomography, scanning electron microscope (SEM) imaging, porosity analysis, and computational simulations of directional sample permeability and thermal conductivity (using geometry data from X-ray imaging). Advantages and disadvantages of each wick design approach were explored in the context of both manufacturability using LPBF, and wick performance. Of the three strategies, the rastered approach was found to have the most potential for applications in future additively manufactured heat pipe designs due to its wide LPBF manufacturability process window and its relatively high permeability with low directional dependence.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104669"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137446","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":"The mirror additive manufacturing process for tool-less fabrication of continuous carbon fiber reinforced thermoplastic resin matrix composite","authors":"Tianhao Zhao,&nbsp;Leyan Chen,&nbsp;Kenan Zhang,&nbsp;Haihang Wang,&nbsp;Jie Yang,&nbsp;Qinglong An,&nbsp;Ming Chen,&nbsp;Jingwei Zhang","doi":"10.1016/j.addma.2025.104680","DOIUrl":"10.1016/j.addma.2025.104680","url":null,"abstract":"<div><div>A mirror additive manufacturing (MAM) process has been proposed, in which dual mutually supported robotic heads simultaneously perform placement and in-situ laser heating curing of thermoplastic prepreg tapes. This approach overcomes the reliance on complex tools in conventional processes, enhancing manufacturing flexibility, cost-efficiency and production efficiency as well as the applicability to special environments such as space, remote areas and disaster zones. The severe instability of temperature and rolling force during the MAM process was effectively addressed by the proposed control strategy combining reinforcement learning with a PID algorithm. Moreover, ply-by-ply decrease in temperature is caused as the cumulative heating effect of the mirror heat sources weakens with the rise of laminate thickness, which is precisely compensated by the proposed temperature stabilization control method, enabling stable temperatures across each ply. Compared with the open-loop MAM system, the stabilization control of temperature and rolling force significantly improves surface quality, reduces internal defects and enhances macro-mechanical performance. The effect of process parameters such as laser power, rolling force and placement speed on surface roughness, internal defects and macro-mechanical characteristics has also been clarified.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104680"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137907","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":"Self-generating multiscale configurations, their CAD features in support of 3D printing and their CAE efficiencies","authors":"Qirui Jin ,&nbsp;Chuang Ma ,&nbsp;Yichao Zhu","doi":"10.1016/j.addma.2025.104670","DOIUrl":"10.1016/j.addma.2025.104670","url":null,"abstract":"<div><div>Additive manufacturing enables the production of a number of multiscale configurations such as lattice structures. However, due to their multiscale complexities, the acquisition of explicit, high-fidelity, resource-saving digital description of lattice configurations is still technically challenging. This article is aimed to introduce a general algorithm for digital presentation of lattice structure, whose constituting cells can be spatially-varying. The natural suitability of the present algorithm with additive manufacturing can be summarised as follows. Firstly, the designed lattice here can be represented fully in line with Computer-Aided Design (CAD) conventions. Secondly, the designed lattice can functionally approximate any multiscale configurations in the sense of resulting in similar responding fields under given loading conditions. Thirdly, the designed lattice can be digitally memorised in a highly compact manner, and an unzipping scheme in parallel with its additive manufacturing process is thus proposed to maintain the number of CAD control points in memory at a low level. Fourthly, mechanical properties of the designed lattice, both its overall compliance and its localised properties, such as its strength, can be evaluated instantly, with the use of a machine-learning-based asymptotic homogenisation and localisation method.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104670"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137909","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":"Thin-plate lattices in AlSi10Mg alloy via laser additive manufacturing: Highly enhanced specific strength and recovery","authors":"Jordan Noronha,&nbsp;Jason Dash,&nbsp;David Downing,&nbsp;Mahyar Khorasani,&nbsp;Martin Leary,&nbsp;Milan Brandt,&nbsp;Ma Qian","doi":"10.1016/j.addma.2025.104664","DOIUrl":"10.1016/j.addma.2025.104664","url":null,"abstract":"<div><div>Metallic lattices have emerged as a class of lightweight, strong, and multifunctional materials with growing applications. However, their specific strengths (strength-to-density ratios) often fall significantly short of those of their bulk metal counterparts. Thin-plate lattices (TPLs), featuring submillimeter-thick metal plates, present a promising solution. Yet, traditional manufacturing methods have long hindered their development. This study investigates laser additive manufacturing and the mechanical properties of axially isotropic AlSi10Mg alloy TPLs, designed with various unit cells, including cubic, cuboctahedron, truncated-octahedron, rhombicuboctahedron, and sphere structures. With densities ranging from 0.57 to 1.13 g/cm³ , these TPLs achieved exceptional specific yield strengths up to 90 % of the base alloy—significantly surpassing the performance of strut-based metallic lattices, which typically achieve 50–60 %. Additionally, under uniaxial compression, the TPLs demonstrated remarkable near-complete peak stress recovery, even at high strain levels (&gt;50 %) or during fragmentation, offering a unique safety mechanism. This recovery was driven by distinct failure modes: at lower densities, fractures progressed layer by layer, leaving intact layers, while at higher densities, crack deflection enhanced resilience. These findings position TPLs as a transformative advancement, combining exceptional specific strength with robust recovery characteristics to outperform conventional lattice designs in multifunctional, high-performance applications.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104664"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137910","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":"Modeling and spatio-temporal optimization of grayscale digital light processing 3D-printed structures with photobleaching resins","authors":"Xiru Fan ,&nbsp;Mengjie Zhang ,&nbsp;Liguo Hu ,&nbsp;Le Dong ,&nbsp;Qinghua Yu ,&nbsp;Biao Zhang ,&nbsp;Kun Zhou ,&nbsp;Dong Wang","doi":"10.1016/j.addma.2025.104659","DOIUrl":"10.1016/j.addma.2025.104659","url":null,"abstract":"<div><div>Grayscale digital light processing (DLP) 3D printing modulates light intensity in each pixel through grayscale values, offering a promising approach for achieving high-resolution printed structures. However, existing theoretical models and optimization methods typically rely on the assumuption of a photo-invariant resin, for simplification. This study demonstrates that the curing depth varies even when the total accumulated dose remains constant, indicating a photo-variant effect. To address this, a spatio-temporal optimization method along with a model are developed, incorporating photobleaching effects, multilayer exposure, and Gaussian beam propagation. The model accurately predicts variations in curing depths at constant doses. Structures are optimized using this model, resulting in several significant improvements: channel heights are reduced to approximately one-fifth of the empirical minimum value with variations below 10 %; concave lenses are optimized with smooth surfaces; and the stair-stepping effect is notably reduced. Additionally, an asymmetric stair-stepping effect is identified between the left and right sides of objects printed at the corner, primarily caused by light divergence. The developed model and spatio-temporal optimization algorithm pave the way for high-fidelity grayscale DLP 3D printing.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104659"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137440","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":"Direct ink writing of alumina-fiber reinforced alumina-matrix composites: Processing and mechanical behavior","authors":"Rohit Malik,&nbsp;Shitong Zhou,&nbsp;Zhuoqi Lucas Li,&nbsp;Oriol Gavalda Diaz,&nbsp;Florian Bouville,&nbsp;Eduardo Saiz","doi":"10.1016/j.addma.2025.104671","DOIUrl":"10.1016/j.addma.2025.104671","url":null,"abstract":"<div><div>Additive manufacturing offers new opportunities for fabricating intricately shaped fiber-reinforced ceramic matrix composites, but challenges remain, such as improving fiber content, eliminating defects to enhance strength, and preserving characteristic toughening mechanisms. In this study, we explore the use of direct ink writing (DIW) for shaping alumina-matrix composites reinforced with short alumina fibers, addressing key challenges. We developed hydrogel-based inks for printing fiber-reinforced ceramics and demonstrated the printability of intricately shaped composites. The inclusion of fibers reduced the yield stress, facilitating extrusion. Additionally, DIW promoted fiber alignment, allowing for precise control over fiber orientation. However, the formation of a rigid fiber network at high concentrations negatively impacts printability and limits fiber content. Furthermore, air entrapment in the fiber network and the use of low sintering temperatures (to avoid fiber damage) result in poor densification and modest mechanical properties. To address these issues, a sol-gel infiltration process was used post-printing, resulting in a 120 % increase in strength and an 88 % increase in toughness. The composites exhibited gradual failure, attributable to a combination of damage formation mechanisms, including matrix microcracking, crack deflection along the fiber-matrix interface, acoustic energy dissipation upon fiber failure, and frictional work during fiber pullout. A maximum fiber content of 35 wt% of the solid content was achieved, and the final composites exhibited a flexural strength of 103.5 MPa, a crack initiation toughness (<em>K</em>_<em>IC</em>) of 2.2 MPa·m¹^/², and a crack propagation toughness (<em>K</em>_<em>J</em>) of 6 MPa·m¹^/².</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104671"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137893","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":"Hydrophilic silicone-based ink derived from amphiphilic siloxane oligomers for the vat photopolymerization printing of embedded-channel fluidic devices","authors":"Li Yan Wong ,&nbsp;Sayan Ganguly ,&nbsp;Xiaowu (Shirley) Tang","doi":"10.1016/j.addma.2025.104691","DOIUrl":"10.1016/j.addma.2025.104691","url":null,"abstract":"<div><div>The emergence of vat photopolymerization (VP) printing as an alternative fabrication method for fluidic devices has led to the rapid development of silicone-based resin material. However, most silicone-based resin materials are hydrophobic in nature, rendering them unsuitable for biomedical applications without post-processing. Herein, we introduce a new type of hydrophilic silicone-based resin material derived from vinyl-terminated amphiphilic siloxane oligomers, acrylamide, and glycidyl methacrylate, for the printing of fluidic devices. We demonstrate the strategy to overcome the challenges associated with amphiphilic-based formulation by adjusting the amphiphilic siloxane oligomer conformation with appropriate solvent blend, resulting in a silicone-based resin material with low pre-gel viscosity, high transparency, and hydrophilic characteristics. Besides, the developed material exhibits tunable elastic properties, excellent polar solvent resistance, and good biocompatibility. Upon photocuring depth tuning, the developed material displays high printing accuracy down to 200 µm in width and 50 µm in height. The material’s ability to replicate embedded fluidic channels with diverse shapes in one-step printing further shows its potential for fluidic device fabrication. The printed devices were revealed to be highly functional with the capability to process fluid at an elevated temperature of up to 100 ºC for 24 hours and a continuous flow rate of up to 20 mL/min. Further demonstration of the hydrogel beads synthesis for drug encapsulation reveals the feasibility of the printed device for real-world biomedical applications. The successful VP printing of hydrophilic silicone-based embedded-channel fluidic devices opened up new avenues for the fabrication of silicone-based fluidic devices for biomedical applications.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"100 ","pages":"Article 104691"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349204","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":"Printability criterion and filler characteristics model for material extrusion additive manufacturing","authors":"James J. Griebler ,&nbsp;Alexander S. Tappan ,&nbsp;Simon A. Rogers ,&nbsp;Anne M Grillet ,&nbsp;Jessica W. Kopatz","doi":"10.1016/j.addma.2025.104651","DOIUrl":"10.1016/j.addma.2025.104651","url":null,"abstract":"<div><div>Material extrusion is an additive manufacturing technique that enables the creation of reproducible and complex hardware by depositing a viscous, shear-thinning ink onto a substrate in a custom-pattern via extrusion through a syringe. The ability of an ink to be extruded onto a substrate in many layers and maintain the desired shape is what defines printability. Printability has historically been investigated in an iterative manner by formulating and printing inks and then performing postmortem analysis of final parts. Highly concentrated pastes continue to pose issues for practitioners as the effect of filler morphology and size dispersity on the ink rheology and corresponding printability is not well understood. A printability criterion based on the particle filler’s maximum packing fraction was recently proposed to provide a general framework to understand printability of particle-filled inks. Inks were found to be printable if the particle loading was within 90–94 % of the maximum packing fraction of the particle. Here we expand on that work to validate the generality of the maximum packing fraction criterion by testing with 10 new single and multimodal particle fillers. The maximum packing fraction calculated from small amplitude oscillatory shear experiments and is found to correctly predict the printability range for all inks. We then utilize statistical methods to develop a filler characteristics model to predict the maximum packing fraction from particle analysis alone. These two methods paired together can significantly speed up development of new inks, increase the performance of material extrusion printing, and improve the stability of printed parts, with less wasted time and materials.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"99 ","pages":"Article 104651"},"PeriodicalIF":10.3,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143137437","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}