Additive manufacturing最新文献

{"title":"Effect of dilution on fabricated functionally graded materials compositions: Modelling and mitigation strategies validated using the Ni-, Fe-, Cu- alloy system","authors":"Zhening Yang ,&nbsp;Cory D. Jamieson ,&nbsp;Zi-Kui Liu ,&nbsp;Allison M. Beese","doi":"10.1016/j.addma.2025.104730","DOIUrl":"10.1016/j.addma.2025.104730","url":null,"abstract":"<div><div>Additive manufacturing (AM) can be used to fabricate functionally graded materials (FGMs) in which composition, and therefore properties, vary spatially within a component. A practical consideration for FGM fabrication is the effects of dilution. In the gradient region of vertically graded FGMs, dilution from the previous layer with a different composition from that being newly deposited can result in the composition of the newly solidified layer deviating from the feedstock composition from the nozzles. In this study, a dilution model for multi-layer FGM samples is proposed and validated experimentally with an Inconel625 (IN625)-Monel400 FGM sample. Factors that affect the deviation from the designed compositional path are discussed and methods for mitigating dilution effects to produce designed path are provided and experimentally demonstrated in a stainless steel 316 L (SS316L)-50/50 wt% SS316L/Ni-Monel400 FGM sample, aiding in precise production of the designed FGM path.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104730"},"PeriodicalIF":10.3,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143577069","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":"Achieving columnar to equiaxed transition in the as-deposited condition via coaxial wire feeding during laser directed energy deposition of Ti-6Al-4V","authors":"Yuan Chen ,&nbsp;Yiming Mao ,&nbsp;Meng Jiang ,&nbsp;Xi Chen ,&nbsp;Huiliang Wei ,&nbsp;Tianyi Han ,&nbsp;Zhe Wang ,&nbsp;Zhenglong Lei ,&nbsp;Peng He ,&nbsp;Yanbin Chen","doi":"10.1016/j.addma.2025.104732","DOIUrl":"10.1016/j.addma.2025.104732","url":null,"abstract":"<div><div>Titanium alloy components fabricated by high-deposition-rate wire-based directed energy deposition (DED) often exhibit coarse prior β grains with a strong solidification texture, which results from the intrinsic melting and solidification conditions experienced by the deposited material. In this work, the columnar to equiaxed β grain transition of Ti-6Al-4V alloy was achieved via a coaxial wire-feeding laser DED process in the as-deposited condition. The coaxial wire laser deposition process was achieved using a coaxial laser head with a vertically fed wire surrounded by an annular beam. Defect-free Ti-6Al-4V parts can be fabricated under both stable liquid bridge and wire penetration metal transfer modes. The optical microscope and electron backscatter diffraction results showed that the thin-walled part fabricated with stable wire penetration mode exhibited a near-fully equiaxed β-grain structure of 200–300 μm size. A 3D multi-physics thermal-fluid model was developed to compute the melting and solidification conditions of the molten pool, revealing the refinement mechanism for the prior β grains. The calculated solidification parameters at the solid/liquid interface predicted mixed columnar + equiaxed grains for the stable wire penetration mode. The results implied that a certain volume of the mushy zone inside the molten pool for the stable wire penetration mode, attributed to the annular-shaped laser heat source with reduced heat input and the specific relative position of the wire to the laser. The unmelted coaxially fed wire in the mushy zone inside the melt pool can serve as heterogeneous nucleation particles, triggering the columnar-to-equiaxed transition. This work provides a method to refine the prior β grains in the as-deposited condition during the wire-based additive manufacturing of titanium alloy without post-processing or alloy modification.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104732"},"PeriodicalIF":10.3,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576975","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":"Improved compressive strength of laser powder bed fused porous tantalum by hot isostatic pressing","authors":"Feng Qin ,&nbsp;Lijia Chen ,&nbsp;Ge Zhou ,&nbsp;Qi Shi ,&nbsp;Binbin Liu ,&nbsp;Xin Liu","doi":"10.1016/j.addma.2025.104729","DOIUrl":"10.1016/j.addma.2025.104729","url":null,"abstract":"<div><div>As structure-function integrated materials, highly interconnected porous materials have many advantages such as load bearing, light weight, and mass transfer. The advancement of additive manufacturing technology has prompted increasing scholarly attention towards the unit cell structural design and specific strength enhancement of the porous material. This study proposes an innovative high-pressure heat treatment technique for the performance optimization of the triply periodic minimal surface (TPMS) porous tantalum (Ta) components fabricated by laser powder bed fusion. The experimental results demonstrate that the hot isostatic pressing (HIP) process at 850 ℃ facilitates closure of internal micropores and enhances compressive strength without compromising the plasticity of porous Ta components. However, due to the oxygen sensitivity of Ta at high temperature, the oxidation rate of Ta samples rapidly increases with temperature. During HIP at 1350 ℃, oxygen atoms invade the Ta matrix to form Ta₂O₅, with the oxides providing stress concentration locations and crack propagation paths, leading to brittle fracture of the 1350-HIP samples. In addition, the anisotropic compressive strength of the porous Ta was further investigated in this study, revealing a greater compressive strength along the horizontal direction compared to that along the building direction.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104729"},"PeriodicalIF":10.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561838","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":"Formation mechanisms of Sn-rich δ phase and its role in strengthening Cu-10Sn manufactured by laser powder bed fusion","authors":"Kangwei Chen ,&nbsp;Bryan Lim ,&nbsp;Leon Zhang ,&nbsp;Boon Xuan Koo ,&nbsp;Simon P. Ringer ,&nbsp;Keita Nomoto","doi":"10.1016/j.addma.2025.104723","DOIUrl":"10.1016/j.addma.2025.104723","url":null,"abstract":"<div><div>Cu-Sn alloys produced via laser powder bed fusion (L-PBF) additive manufacturing (AM) have gained significant attention because they combine the advantages of AM relevant to intricate component design with outstanding combinations of strength, ductility, and resistance to wear and corrosion. However, a detailed understanding of the microstructure that contributes to the enhancement of the mechanical properties of L-PBF Cu-10Sn alloys remains unclear. In particular, there is a lack of understanding of the formation mechanisms of the Sn-rich δ phase commonly observed in Cu-10Sn. This study reveals two distinct variants of the δ phase possessing unique morphological characteristics. These characteristics are attributed to the local solidification conditions inherent to the melt pool boundaries versus those at the interiors of melt pools. A phase transformation pathway that elucidates the origin of the morphological variants of the δ phase from the Sn-rich metastable phases during the cyclic heating of the AM process is proposed. We report superior mechanical properties in L-PBF Cu-10Sn compared to those of conventionally manufactured counterparts due to the synergistic contributions from grain boundaries, dislocations, and the δ phase. Notably, the δ phase alone contributes approximately 22 % to the overall strength observed in the L-PBF Cu-10Sn alloy. The discovery of two types of distinct Sn-rich δ phase offers key insights into precise microstructural control in AM Cu-Sn alloys to enhance mechanical properties, providing practical strategies for improving material performance for diverse applications in automotive, aerospace, and machinery industries.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104723"},"PeriodicalIF":10.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576974","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":"Flashing light curing strategy for shape fidelity improvement in photopolymerization-based ceramic additive manufacturing","authors":"Shakeel Abbas ,&nbsp;Sinuo Zhang ,&nbsp;Chang Woo Gal ,&nbsp;Imam Akbar Sutejo ,&nbsp;Yeong-Jin Choi ,&nbsp;Hui-suk Yun","doi":"10.1016/j.addma.2025.104726","DOIUrl":"10.1016/j.addma.2025.104726","url":null,"abstract":"<div><div>We proposed a flashing mechanism as an alternative to continuous illumination to counter scattering-induced overcuring in photopolymerization-based ceramic additive manufacturing (AM). Unlike the conventional continuous illumination method, the flashing technique exposes the ceramic slurry to multiple flashes of ultraviolet (UV) light in stages. The duration of the flash determines the radical formation in the UV-exposed region and their degree of diffusion in the unexposed area due to scattering. Off-times between consecutive flashes ensure the complete radical utilization, reaction termination, and the formation of a prepolymerized layer with reduced scattering efficiency. The study investigates the effects of flash duration and off-time on slurry curability and overcuring for zirconia (ZrO₂), titania (TiO₂), and alumina (Al₂O₃), at various solid loadings and compared with continuous illumination. Furthermore, the degree of conversion (DoC) was calculated and compared for both illumination methods. Lattice structures printed using both methods were subjected to debinding and sintering for densification, followed by an evaluation of their material properties. The results demonstrate that the flashing effectively controls scattering-induced overcuring with shorter flash durations and longer off-times, enhancing the printing accuracy. Although, flashing irradiation led to slightly low monomer conversion, which affected the interlayer strength in green bodies, the final sintered structures exhibited comparable density and mechanical properties to those printed continuously. These findings suggest that the flashing technique is a viable alternative to continuous AM to achieve high-shape fidelity by mitigating scattering effects in photopolymerization-based ceramic AM without compromising material properties.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104726"},"PeriodicalIF":10.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143561839","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":"Modulated laser thermal interrogation (MLTI): A novel in situ metal powder evaluation technique for laser powder bed fusion","authors":"Sina Ghadi ,&nbsp;Xiaobo Chen ,&nbsp;Nicholas S. Tomasello ,&nbsp;Nicholas A. Derimow ,&nbsp;Srikanth Rangarajan ,&nbsp;Guangwen Zhou ,&nbsp;Scott N. Schiffres","doi":"10.1016/j.addma.2025.104728","DOIUrl":"10.1016/j.addma.2025.104728","url":null,"abstract":"<div><div>Assessment of metal powders in powder bed additive manufacturing is crucial, as the quality of the powders significantly impacts the final printed parts. This study introduces a novel technique to characterize metal powders by analyzing changes in their thermal properties, specifically heat capacity and thermal conductivity. The Modulated Laser Thermal Interrogation (MLTI) method utilizes frequency domain responses of temperature to facilitate this characterization. To validate the performance of MLTI, a benchtop setup was made, which identified distinct thermal responses related to various material features, including core material detection, age, oxygen content, and particle size distribution. The powder was heated by a 7 W laser (445 nm) that was modulated at frequencies between 100 Hz and 2 kHz. By capturing the IR emission of the surface with the photodetector and sending the signals to the lock-in amplifier, demodulated amplitude and phase could be extracted which represent the characteristics of the metal powder. We tested common metal powders used in powder bed fusion, such as Cu, AlSi10Mg, SS316L, IN718, and Ti-6Al-4V G5 and G23, to demonstrate the capabilities of the MLTI method. The frequency-domain measurements provided by MLTI offer reduced noise compared to traditional methods. By leveraging machine learning, we could accurately characterize the powder, identify the core material of the powder, determine whether the powder is fresh or reused, assess interstitial oxygen content, verify the powder deposition layer thickness, and analyze particle size distribution. This enhances quality control and process monitoring in powder bed additive manufacturing.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104728"},"PeriodicalIF":10.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143577068","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":"Low Young’s modulus in laser powder bed fusion processed Ti–15Mo–5Zr–3Al alloys achieved by the control of crystallographic texture combined with the retention of low-stability bcc structure","authors":"Shota Higashino ,&nbsp;Daisuke Miyashita ,&nbsp;Takuya Ishimoto ,&nbsp;Eisuke Miyoshi ,&nbsp;Takayoshi Nakano ,&nbsp;Masakazu Tane","doi":"10.1016/j.addma.2025.104720","DOIUrl":"10.1016/j.addma.2025.104720","url":null,"abstract":"<div><div>Metastable <em>β</em> (body-centered cubic)-phase Ti alloys, quenched from a high-temperature <em>β</em>-phase field, have attracted great interest as biomedical implants, owing to their low Young’s modulus. Recently, the application of additive manufacturing (AM) to <em>β</em>-phase Ti alloys has gathered much attention, because the AM process can form anisotropic crystallographic texture in which an elastically soft direction is preferentially oriented, resulting in low Young’s modulus in a specific direction. However, the effects of anisotropic texture and microstructure formed by the AM process on anisotropic elastic properties have not been clarified in detail. In the present study, we measured all the independent elastic stiffness components of <em>β</em>-phase Ti–15Mo–5Zr–3Al (mass%) alloys, prepared by bidirectional scanning with (XY-scan) and without (X-scan) an interlayer rotation of 90° in laser powder bed fusion (LPBF), one of the AM processes, using resonant ultrasound spectroscopy. The measurements revealed that the LPBF-processed Ti alloys exhibited strong elastic anisotropy and a low Young’s modulus (below 60 GPa) in the &lt;100&gt;-oriented direction of the alloy prepared by the XY-scan. Furthermore, micromechanics calculations based on Eshelby’s inclusion theory revealed that the single crystal constituting the alloys prepared by LPBF had almost the same elastic stiffness as that of a single crystal prepared by the floating zone melting, which indicated that the metastable <em>β</em> phase was retained by suppressing an easily occurring <em>β-</em> to <em>ω-</em>phase transformation during LPBF. These results indicate that texture control combined with retention of the metastable <em>β</em> phase by LPBF achieves biocompatible low Young’s modulus.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104720"},"PeriodicalIF":10.3,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576976","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":"Generating new cellular structures for additive manufacturing through an unconditional 3D latent diffusion model","authors":"Leijian Yu ,&nbsp;Yong En Kok ,&nbsp;Luke Parry ,&nbsp;Ender Özcan ,&nbsp;Ian Maskery","doi":"10.1016/j.addma.2025.104712","DOIUrl":"10.1016/j.addma.2025.104712","url":null,"abstract":"<div><div>Advances in additive manufacturing (AM) have facilitated the fabrication of cellular structures inspired by those in the natural world. But the design of complex, tessellating cellular structures remains a challenge for human designers, and only a small number of geometries, defined either by connected walls or struts, or by surface equations, have been investigated. This study introduces generative deep learning to the problem, with the aim of synthesising novel cellular geometries producible by AM. Our unconditional 3D latent diffusion model (U3LDM) explores the design space from a new class of training data comprising 10,650 unit cells. A critical task involved developing a varied set of cell geometries based on random permutations of trigonometric surface equations. This was coupled with a stringent set of pass/fail tests to ensure the generated structures possessed structural connectivity and could tessellate in 3D. The new cellular structures were analysed numerically using finite element analysis, fabricated by polymer AM, and subjected to compression tests to verify their manufacturability and mechanical properties. Results indicate that the U3LDM is capable of generating new ‘unseen’ cellular structures with geometries and mechanical properties consistent with those of the training specimens. This method also demonstrates the potential universal technique for creating nature-inspired and AM-manufacturable structures beyond the currently limited set of human-derived geometries.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"101 ","pages":"Article 104712"},"PeriodicalIF":10.3,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143529705","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":"Ductile fracture model describing the impact of internal pores: Model development and validation for additively manufactured Ti-6Al-4V","authors":"Erik T. Furton ,&nbsp;Allison M. Beese","doi":"10.1016/j.addma.2025.104722","DOIUrl":"10.1016/j.addma.2025.104722","url":null,"abstract":"<div><div>Additively manufactured metals often contain pores, which limit the strength and ductility of resulting components. In this study, a ductile fracture model was developed to describe the effect of pore size, in terms of absolute and relative metrics, on fracture strain under uniaxial tension. The model approximates lack of fusion (LoF) pores as penny-shaped cracks, and damage accumulation was based on the J-integral and secondary <em>Q</em> parameter. The model was calibrated with Ti-6Al-4V samples with intentionally introduced pores fabricated by laser powder bed fusion (PBF-LB) additive manufacturing (AM) in as-built and heat-treated conditions. The model captures the experimentally observed size effect, where for a given pore area fraction, larger samples fracture at smaller strains. By identifying the critical pore size for a single, isolated pore for either load or displacement-controlled applications, the model developed in this study is a crucial step to developing a comprehensive fracture model for establishing confidence in the structural capability of pore-containing additively manufactured components.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"102 ","pages":"Article 104722"},"PeriodicalIF":10.3,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143577067","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":"Three-dimensional printing of complex structured silica glass based on high-strength green parts","authors":"Yazhou Peng ,&nbsp;Wenyue Zhao ,&nbsp;Zhao Wang ,&nbsp;Lei Shi ,&nbsp;Wenjing Hua ,&nbsp;Xiaoxia Yang ,&nbsp;Jie Wang ,&nbsp;Weidong Fei ,&nbsp;Yu Zhao ,&nbsp;Changhong Wang","doi":"10.1016/j.addma.2025.104725","DOIUrl":"10.1016/j.addma.2025.104725","url":null,"abstract":"<div><div>Three-dimensional (3D) printing of silica glass provides significant advantages for the fabrication of silica glass with complex structures. However, auxiliary support structures are generally needed due to the low stiffness and strength of green parts, which limits the flexibility of the structure design. It is imperative to increase the strength of the green part and remove the support structures for improving the molding capacity and printing quality. This study introduces an approach for 3D printing of silica glass with complex structures by digital light processing (DLP) based on the high-strength green parts, which exhibits superior molding capacity. By comparing three monomers of 2-hydroxyethyl methacrylate (HEMA), 2-hydroxyethyl acrylate (HEA), and 4-hydroxybutyl acrylate (4-HBA), it was demonstrated that high photopolymerization reactivity is a key factor for improving the mechanical properties of green parts. Green parts printed with 4-HBA exhibit a combination of high modulus, high strength, and high conversion degree. Following heat treatment, these complex-structured green parts transform into dense, transparent silica glass. The specific compressive strength of silica glass with a lattice meta-structure reaches 4.94 × 10⁴ N m kg⁻¹. This study enhances structural design flexibility in the 3D printing of silica glass, providing a novel perspective for future research.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"101 ","pages":"Article 104725"},"PeriodicalIF":10.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526974","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}