Additive manufacturing letters最新文献_第8页

Material extrusion with integrated compression molding of NdFeB/SmFeN nylon bonded magnets using small- and large-scale pellet-based 3D-printers 使用小型和大型基于颗粒的3d打印机对钕铁硼/SmFeN尼龙粘结磁铁进行综合压缩成型的材料挤压

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-04-01 DOI: 10.1016/j.addlet.2025.100282

Kaustubh Mungale , Vipin Kumar , Mariappan Parans Paranthaman , Brian C. Sales , Harshida Parmar , Ikenna C. Nlebedim , Brittany Rodriguez , Uday Kumar Vaidya

High-density bonded rare-earth magnets are manufactured using pellet-fed additive manufacturing (AM)/material extrusion and an integrated additive manufacturing-compression molding (AM-CM) process. Neodymium iron boron – samarium iron nitride in polyamide 12 (NdFeB-SmFeN/PA12) of 93 % weight fraction (65 % volume fraction) are used for the study. The mechanical properties (tensile strength and modulus), magnetic properties (maximum energy density, coercivity, remanence) are reported. Manufacturing parameters such as layer height, barrel temperatures, screw speed and gantry feed rate are optimized to obtain the highest possible density of the magnets using a small-scale desktop material extrusion printer. Large scale integrated additive manufacturing-compression molding (AM-CM) is then utilized to increase the density of the magnets by reducing porosity defects common in the material extrusion process. The density of as-printed magnets was 5.2 g/cm³ with a BH_max value of 124.14 kJ/m³, tensile strength of 20 MPa and a modulus of 2 GPa. AM-CM increased the density of the compound by 5.5 % (5.49 g/cm³). The reduction in porosity was confirmed using X-ray tomography (XCT). Improvement in mechanical strength of the material was also observed, with an increase in tensile strength of 25 % (25.09 MPa) and increase in tensile modulus of 275 % (5.49 GPa). Scanning electron microscopy showed increased particle-matrix adhesion with the integrated AM-CM process.

高密度粘结稀土磁体的制造采用颗粒喂料增材制造(AM)/材料挤压和集成增材制造-压缩成型（AM- cm）工艺。采用质量分数为93%（体积分数为65%）的钕铁硼-氮化铁钐（NdFeB-SmFeN/PA12）。报告了材料的力学性能（抗拉强度和模量）、磁性能（最大能量密度、矫顽力、剩余力）。制造参数，如层的高度，桶的温度，螺杆速度和龙门进料速度进行优化，以获得尽可能高的磁铁密度使用小型台式材料挤压打印机。然后利用大规模集成增材制造-压缩成型（AM-CM）通过减少材料挤压过程中常见的孔隙缺陷来增加磁体的密度。打印磁体的密度为5.2 g/cm3， BHmax为124.14 kJ/m3，抗拉强度为20 MPa，模量为2 GPa。AM-CM使化合物的密度提高了5.5% （5.49 g/cm3）。通过x射线断层扫描（XCT）证实孔隙度降低。材料的机械强度也有所提高，抗拉强度提高25% (25.09 MPa)，抗拉模量提高275% （5.49 GPa）。扫描电镜显示，集成AM-CM工艺增加了颗粒-基质的粘附性。

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引用次数: 0

On cyber sabotage risks in automated manufacturing of advanced composites 先进复合材料自动化制造中的网络破坏风险研究

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-04-01 DOI: 10.1016/j.addlet.2025.100280

Saral Mittal , Hammond Pearce , Mark Yampolskiy , Ebrahim Oromiehie , B. Gangadhara Prusty

Recent advancements in the manufacturing of layered composite structures have seen the deployment of automated control systems, with computers used for both design protocols and control of manufacturing processes. However, as digitisation and computerisation of composites manufacturing advances, so too grows the potential exposure to cyber-attacks. Given that large manufacturing companies, government organisations, and defence agencies are increasingly utilising parts made out of fibre-reinforced composite materials, this security exposure must be acknowledged and managed carefully.

From other computerised manufacturing domains, we know that adversaries may aim to steal technical data such as digital design files (for example, for espionage or to infringe on Intellectual Property, IP) or to sabotage manufactured parts. Both can have consequences reaching far beyond immediate financial or physical damage. While it can be assumed that the adversarial goals are similar for composites manufacturing, the attack methods have not been explored or studied yet. This paper seeks to address this gap in part, by providing the first holistic security analysis of potential sabotage attacks in automated composites manufacturing using modern equipment. This security analysis provides a framework for composite manufacturers to identify vulnerabilities in their production workflows that are susceptible to cyber-attacks, while also providing opportunity to design customised countermeasures to strengthen the security of their automated manufacturing processes.

最近在层状复合材料结构制造方面的进展已经看到了自动化控制系统的部署，计算机用于设计协议和制造过程的控制。然而，随着复合材料制造的数字化和计算机化的进步，网络攻击的潜在风险也在增加。鉴于大型制造公司、政府组织和国防机构越来越多地使用由纤维增强复合材料制成的部件，必须承认并仔细管理这种安全风险。从其他计算机化的制造领域，我们知道对手可能会窃取技术数据，如数字设计文件（例如，用于间谍活动或侵犯知识产权）或破坏制造部件。两者的后果都可能远远超出直接的经济或物理损失。虽然可以假设复合材料制造的对抗目标是相似的，但攻击方法尚未被探索或研究。本文试图通过提供使用现代设备的自动化复合材料制造中潜在破坏攻击的第一个整体安全分析来部分解决这一差距。这种安全分析为复合材料制造商提供了一个框架，以识别其生产工作流程中容易受到网络攻击的漏洞，同时也提供了设计定制对策的机会，以加强其自动化制造过程的安全性。

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引用次数: 0

Simultaneously improving strength and corrosion resistance of additively manufactured Mg-Gd-Zr alloy by in-situ alloying with Al 通过原位合金化铝，同时提高了增材制造Mg-Gd-Zr合金的强度和耐腐蚀性

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-04-01 DOI: 10.1016/j.addlet.2025.100279

Ziyi Liu, Qingchen Deng, Yiwen Ding, Ziyan Li, Jiacheng Wang, Liming Peng

Additive manufacturing of magnesium (Mg) alloy components with intricate geometries via laser powder bed fusion (LPBF) offers significant advantages for lightweight engineering applications. However, as a commonly issue of Mg alloys, the corrosion resistance of LPBF-Mg alloys is even worse than their cast and deformed counterparts. In-situ alloying provides a rapid pathway for composition modification tailored for the LPBF process. In this study, aluminum (Al) is introduced through in-situ alloying to prepare Mg-10Gd-xAl-Zr (GA10xK, x = 0.5, 1, 2 wt. %) alloys using blended Mg-10Gd-Zr and Mg-15Al powders. By employing a lower scanning speed during LPBF, a uniform distribution of Al throughout the as-built components is achieved. The increase in Al content leads to the progressive enhancement in grain refinement and the transformation of secondary phases from Mg₃Gd to Al₂Gd with a significant reduction in size and a notable increase in number density. These microstructural transformations yield a synchronous enhancement in strength and corrosion resistance with increasing Al content. The yield strength and ultimate tensile strength of the GA102K alloy reach 328 MPa and 350 MPa, respectively, with a minimized corrosion rate of 0.787 mm/yr., surpassing the mechanical and corrosion performance of both LPBF and semi-continuous cast G10K alloys.

通过激光粉末床熔合（LPBF）增材制造具有复杂几何形状的镁（Mg）合金部件为轻量化工程应用提供了显着优势。然而，作为镁合金的一个普遍问题，lpbf -镁合金的耐腐蚀性甚至比铸造和变形的镁合金更差。原位合金化为LPBF工艺提供了一种快速的成分改性途径。本研究采用原位合金化方法引入铝（Al），用Mg-10Gd-Zr和Mg-15Al混合粉末制备Mg-10Gd-xAl-Zr （GA10xK, x = 0.5, 1, 2 wt. %）合金。通过在LPBF过程中采用较低的扫描速度，可以实现Al在整个构建组件中的均匀分布。随着Al含量的增加，晶粒细化程度逐渐增强，二次相由Mg3Gd向Al2Gd转变，晶粒尺寸显著减小，数量密度显著增加。随着Al含量的增加，这些微观结构的转变产生了强度和耐腐蚀性的同步增强。GA102K合金的屈服强度和极限抗拉强度分别达到328 MPa和350 MPa，腐蚀速率最小为0.787 mm/yr。，超过了LPBF和半连铸G10K合金的机械和腐蚀性能。

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引用次数: 0

Enhanced superelasticity and notable elastocaloric effect of Cu71Al17.5Mn11.5 shape memory alloys by laser-based powder bed fusion 激光粉末床熔合Cu71Al17.5Mn11.5形状记忆合金的超弹性增强和显著的弹热效应

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-04-01 DOI: 10.1016/j.addlet.2025.100281

Xiang Li , Zeming Fan , Qijie Zhai , Gang Wang , Xiang Lu , Hanyang Qian , Rui Cai , Daqiang Jiang , Jian Liu

Cu-based shape memory alloys (SMAs) with highly oriented columnar grains and high densities are promising candidates for solid-state refrigeration. In this work, the Cu₇₁Al_17.5Mn_11.5 alloys with a strong 〈001〉 texture columnar grains and a high relative density were fabricated using laser-based powder bed fusion of metals (PBF-LB/M) technique. The Cu₇₁Al_17.5Mn_11.5 alloys exhibited enhanced superelasticity, with a superelastic strain of 6.2 %. A maximum recoverable strain of 8.5 % was achieved under 9 % compressive loading, which includes both superelastic and elastic strain components. Additionally, a notable elastocaloric temperature change of 8.0 K was achieved upon fast unloading under adiabatic conditions. The phase transformation behavior has been systematically investigated by the digital image correlation (DIC) and the transmission wide-angle X-ray diffraction measurements. The current results suggest that the additive manufacturing could be a promising route for near-net-shape high-performance Cu-based elastocaloric refrigerants.

具有高取向柱状晶粒和高密度的cu基形状记忆合金（SMAs）是固态制冷的理想材料。采用激光粉末床金属熔合（PBF-LB/M）技术制备了Cu71Al17.5Mn11.5合金，该合金具有强的< 001 >织构、柱状晶粒和较高的相对密度。Cu71Al17.5Mn11.5合金表现出增强的超弹性，超弹性应变为6.2%。在9%的压缩载荷下，最大可恢复应变达到8.5%，其中包括超弹性和弹性应变分量。此外，在绝热条件下快速卸载时，实现了8.0 K的显著弹性热温度变化。通过数字图像相关（DIC）和透射广角x射线衍射测量系统地研究了相变行为。目前的结果表明，增材制造可能是近净形状高性能cu基弹性热制冷剂的有前途的途径。

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引用次数: 0

Enhancing dental model accuracy through optimized vat photopolymerization additive manufacturing parameters 通过优化大桶光聚合增材制造参数，提高牙科模型精度

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-03-15 DOI: 10.1016/j.addlet.2025.100278

Clément Tien , Camille Jean , Lucas Poupaud , Floriane Laverne , Frédéric Segonds

This study investigates the key additive manufacturing (AM) process parameters that influence the dimensional accuracy of dental models produced using the vat photopolymerization Digital Light Processing (DLP) technology. By applying the Taguchi method, 7AM process factors were analyzed. A standardized post-processing protocol was used to maintain consistency, allowing a focused assessment of the printing parameters. Dimensional deviations were analyzed using 3D scanning and point cloud comparison software, with particular attention to reducing warping and shrinkage. The results identified layer thickness, projector power, exposure energy, and vat temperature as the key AM factors affecting the accuracy of the final model. These findings highlight the importance of optimizing these parameters to achieve high-quality dental models, contributing to future advancements in precision and efficiency. Further research is recommended to determine optimal settings for different resins and more complex dental structures.

本研究探讨了影响使用还原光聚合数字光处理（DLP）技术生产的牙齿模型尺寸精度的关键增材制造（AM）工艺参数。采用田口法对7AM工艺因素进行了分析。采用标准化的后处理方案来保持一致性，以便对打印参数进行重点评估。使用三维扫描和点云比较软件分析尺寸偏差，特别注意减少翘曲和收缩。结果确定了层厚度、投影机功率、曝光能量和还原缸温度是影响最终模型精度的关键AM因素。这些发现强调了优化这些参数以实现高质量牙齿模型的重要性，有助于未来精度和效率的提高。建议进一步研究以确定不同树脂和更复杂的牙齿结构的最佳设置。

引用次数: 0

Qualification of additively manufactured polymer fluid manifolds for life-detection instruments 生命检测仪器用增材制造聚合物流体歧管的鉴定

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-03-04 DOI: 10.1016/j.addlet.2025.100277

Theresa Juarez, Nathan J. Oborny, Andrew Berg, Aaron C. Noell

The development of autonomous life detection instruments is being driven by the advancement of multiple space exploration missions to investigate the subsurface oceans of icy worlds, particularly Titan, Enceladus, and Europa. A fundamental feature of this type of instrument is a compact, reliable, and chemically inert internal liquid transport network. Additively manufactured (AM) custom liquid manifolds produced via vat photopolymerization (VPP) methods can meet these requirements. However, before these materials can be considered, basic spaceflight requirements, qualification for flight worthiness and functionality must be addressed. In this study, mechanical properties, outgassing behavior, polymeric characteristics, and chemical compatibility are assessed for select commercially available AM polymers. The results indicate basic materials qualification requirements are met, including sufficiently characterized mechanical properties, the identification of a bakeout protocol for reduced outgassing to meet NASA standards, and chemical compatibility with liquids and reagents used in candidate instrumentation under development for life detection missions.

自主生命探测仪器的发展是由多个太空探索任务的进步推动的，这些任务旨在调查冰冷世界的地下海洋，特别是土卫六、土卫二和木卫二。这种类型的仪器的一个基本特点是紧凑，可靠，化学惰性的内部液体输送网络。通过还原光聚合（VPP）方法生产的增材制造（AM）定制液体歧管可以满足这些要求。然而，在考虑这些材料之前，必须解决基本的航天要求、飞行价值和功能的资格。在本研究中，对选择的市售增材制造聚合物的机械性能、脱气行为、聚合物特性和化学相容性进行了评估。结果表明，基本的材料资格要求得到满足，包括充分表征的机械性能，确定了减少脱气的烘烤方案，以满足NASA的标准，以及与正在开发的用于生命探测任务的候选仪器中使用的液体和试剂的化学相容性。

{"title":"Qualification of additively manufactured polymer fluid manifolds for life-detection instruments","authors":"Theresa Juarez, Nathan J. Oborny, Andrew Berg, Aaron C. Noell","doi":"10.1016/j.addlet.2025.100277","DOIUrl":"10.1016/j.addlet.2025.100277","url":null,"abstract":"<div><div>The development of autonomous life detection instruments is being driven by the advancement of multiple space exploration missions to investigate the subsurface oceans of icy worlds, particularly Titan, Enceladus, and Europa. A fundamental feature of this type of instrument is a compact, reliable, and chemically inert internal liquid transport network. Additively manufactured (AM) custom liquid manifolds produced via vat photopolymerization (VPP) methods can meet these requirements. However, before these materials can be considered, basic spaceflight requirements, qualification for flight worthiness and functionality must be addressed. In this study, mechanical properties, outgassing behavior, polymeric characteristics, and chemical compatibility are assessed for select commercially available AM polymers. The results indicate basic materials qualification requirements are met, including sufficiently characterized mechanical properties, the identification of a bakeout protocol for reduced outgassing to meet NASA standards, and chemical compatibility with liquids and reagents used in candidate instrumentation under development for life detection missions.</div></div>","PeriodicalId":72068,"journal":{"name":"Additive manufacturing letters","volume":"13 ","pages":"Article 100277"},"PeriodicalIF":4.2,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of raster orientation on large-scale robotic 3D printing of short carbon fiber-reinforced PLA composites 栅格取向对短碳纤维增强PLA复合材料大规模机器人3D打印的影响

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-02-18 DOI: 10.1016/j.addlet.2025.100276

E. Baharlou , J. Ma

Additive manufacturing in building construction can be extended for mass customization of building components or even complex mold making. This study examines the process parameters of raster orientation of short carbon fiber-reinforced polylactic acid (SCF-PLA) and neat PLA in large-scale 3D printing. Three raster orientations—unidirectional, cross-ply, and quasi-isotropic layups—were printed using a pellet extruder assembled on an industrial robotic arm. Tensile and flexural tests were conducted to characterize the differences between SCF-PLA and neat PLA across all raster orientations. This study shows that neat PLA has higher tensile strength compared to SCF-PLA, and quasi-isotropic orientation can improve the week mechanical properties of both SCF-PLA and PLA. This research highlights the interface bonding challenges encountered with larger 3D printed filaments, which result in more significant pores. Furthermore, any factor that modifies rheological properties of the filament, such as carbon filling, can lead to a higher likelihood of material defects. To understand this discrepancy, microstructure analyses were conducted on intact and fractured 3D printed samples, including the analysis of micro voids, interlayer voids, and bonding between SCF and the PLA matrix. This suggests that the effects of quasi-isotropic layups can be applied to enhance 3D print large-scale polymer-based building components.

建筑施工中的增材制造可以扩展到建筑部件的大规模定制甚至复杂的模具制造。研究了短碳纤维增强聚乳酸（SCF-PLA）和整齐聚乳酸在大规模3D打印中的光栅取向工艺参数。三种光栅方向——单向、交叉铺层和准各向同性铺层——使用装配在工业机械臂上的颗粒挤出机进行打印。进行了拉伸和弯曲试验，以表征SCF-PLA和整齐PLA在所有光栅方向上的差异。研究表明，纯PLA的抗拉强度高于SCF-PLA，准各向同性取向可以改善SCF-PLA和PLA的周力学性能。这项研究强调了更大的3D打印细丝所遇到的界面粘合挑战，这会导致更大的孔隙。此外，任何改变长丝流变特性的因素，如碳填充，都可能导致材料缺陷的可能性更高。为了理解这种差异，研究人员对完整和断裂的3D打印样品进行了微观结构分析，包括微观空隙、层间空隙以及SCF与PLA基体之间的结合。这表明准各向同性铺层的效果可以应用于增强3D打印大型聚合物建筑组件。

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引用次数: 0

Process screening in additive manufacturing: Detection of keyhole mode using surface topography and machine learning 增材制造中的工艺筛选：使用表面形貌和机器学习检测钥匙孔模式

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-02-17 DOI: 10.1016/j.addlet.2025.100275

Mingzhang Yang, Ali Rezaei, Mihaela Vlasea

Screening of defective additive manufactured (AM) parts is crucial for ensuring process consistency and part reliability, yet common microstructural inspection methods can be time-consuming or destructive. This study explores how surface analysis combined with machine learning (ML) algorithms can effectively infer the microstructure of laser powder bed fusion (LPBF) parts. As a case study, non-spherical ZrH₂ nanoparticle-enhanced AA7075 aluminum powders was fabricated using 60 different LPBF recipes. ML classification models were then employed to link side-surface topographical features to keyhole melting occurring within the parts. Among the tested ML models, random forest (RF) achieving a testing accuracy of 95 % and an F1-score of 0.98, outperforming both the neural network (NN) and support vector machine (SVM) models. To enhance the interpretability of the ML model, the RF model was leveraged to identify the hierarchical importance of surface features associated with keyhole melting mode. This resulted in the development of keyhole-probability maps based on superficial surface parameters, providing engineers with an effective and easy-to-use tool for screening keyhole mode parts. While further validation is needed, the proposed strategy lays a foundation for leveraging surface topography to infer microstructural features and adapting the method to different material systems.

筛查有缺陷的增材制造（AM）零件对于确保工艺一致性和零件可靠性至关重要，但常见的微观结构检测方法可能会耗费大量时间或具有破坏性。本研究探讨了表面分析与机器学习（ML）算法相结合如何有效地推断激光粉末床熔融（LPBF）零件的微观结构。作为案例研究，使用 60 种不同的 LPBF 配方制造了非球形 ZrH₂ 纳米粒子增强 AA7075 铝粉。然后采用 ML 分类模型将侧面表面地形特征与零件内部发生的锁孔熔化联系起来。在测试的 ML 模型中，随机森林（RF）的测试准确率达到 95%，F1 分数为 0.98，优于神经网络（NN）和支持向量机（SVM）模型。为了提高 ML 模型的可解释性，利用 RF 模型识别了与钥匙孔熔化模式相关的表面特征的层次重要性。这样就开发出了基于表面参数的锁孔概率图，为工程师筛选锁孔模式零件提供了有效且易于使用的工具。虽然还需要进一步验证，但所提出的策略为利用表面形貌推断微观结构特征以及将该方法适用于不同材料系统奠定了基础。

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引用次数: 0

Influence of the laser strategy on bi-metallic interfaces printed via multi-material laser-based powder bed fusion 激光策略对多材料激光粉末床熔合打印双金属界面的影响

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-02-10 DOI: 10.1016/j.addlet.2025.100274

Isabel B. Prestes, Eric A. Jägle

Metallic Multi-material Additive Manufacturing (MMAM) is an emerging research topic, with potential applications in heat exchangers, metamaterials and satellite components. In recent years, new multi-material laser powder bed fusion (PBF-LB) techniques have been developed. However, processing challenges may arise, since materials with dissimilar properties are mixed at the interfaces, which might lead to defects such as cracks. This work aims to investigate the influence of different laser scan strategies to achieve sound interfaces with different material mixing gradients. The samples, made of Inconel 718 and Invar were deposited by the patterning drums technique and were analyzed by means of optical microscopy and energy-dispersive X-ray spectroscopy (EDS) mappings and line scans. The orientation in which melt pools cross the material interface plays an important role in mixing the materials. Different orientations in subsequent layers create a certain “jagged” pattern of mixing at the interface. Sigmoid functions of Boltzmann fitted to the line scans show a significant slope steepness increase – up to 75 % – in the element count from double scan to single scan, suggesting a stronger material mixing. The double scan strategy leads to porosity at the interface and thus should be avoided. The remelt at the interface partially healed defects such as cracks but does not seem to influence the mixing width at the interface. These findings give general guidance for selecting scan strategies in MMAM depending on the desired mixing pattern at the material interface.

金属多材料增材制造（MMAM）是一个新兴的研究课题，在热交换器、超材料和卫星部件等领域具有潜在的应用前景。近年来，新型多材料激光粉末床熔融技术得到了发展。然而，由于具有不同性能的材料在界面处混合，可能导致裂纹等缺陷，因此可能会出现加工挑战。本工作旨在研究不同激光扫描策略对不同材料混合梯度下获得声音界面的影响。采用模鼓法沉积了由Inconel 718和Invar制成的样品，并用光学显微镜、能谱图和线扫描对样品进行了分析。熔池穿过材料界面的方向对材料的混合起着重要的作用。在随后的层中，不同的方向在界面上形成了某种“锯齿状”的混合模式。拟合线扫描的玻尔兹曼Sigmoid函数显示，从两次扫描到一次扫描，元素计数的斜率陡度显著增加，高达75%，表明材料混合更强。双重扫描策略会导致界面处出现孔隙，因此应避免。界面处的熔体部分修复了裂纹等缺陷，但似乎对界面处的混合宽度没有影响。这些发现为根据材料界面所需的混合模式选择MMAM扫描策略提供了一般指导。

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引用次数: 0

Impact of a typical scanner delay processing parameter on local microstructure in metallic laser-based powder bed fusion 典型扫描仪延迟处理参数对金属激光粉末床熔合中局部显微组织的影响

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-02-09 DOI: 10.1016/j.addlet.2025.100273

Brenda Leticia Valadez Mesta , Pascal Thome , Marcus C. Lam , Sammy Tin , Jorge Mireles , Ryan B. Wicker

In laser-based powder bed fusion of metals (PBF-LB/M), variations in laser scanner movements, particularly lesser-studied parameters like scanner delays that control laser directional changes, can influence the microstructure in a part during fabrication as each of typically millions of individual laser vectors impact part thermal history and resulting microstructure. While the impact of commonly researched parameters such as laser power, scan speed, hatch spacing, and layer thickness on part microstructure have been well studied, considerably less attention has been given to scanner delays such as the polygon delay. This study uses electron backscatter diffraction to investigate the microstructural variations caused by polygon delay values ranging from 0 to 450 microseconds, beginning with individual scan tracks. The study then extends single tracks to a simple three-dimensional part to examine if microstructure differences due to polygon delays may be influenced by localized heating and cooling caused by nearby hatch vectors and successive layers. The results reveal that varying polygon delay clearly affects grain morphology during individual scan tracks, although these effects are less clear during a three-dimensional build. Future PBF-LB/M studies should focus more on understanding time-resolved laser beam processing effects to better reduce inconsistencies and improve part quality.

在基于激光的粉末床金属熔合（PBF-LB/M）中，激光扫描仪运动的变化，特别是像控制激光方向变化的扫描仪延迟等较少研究的参数，会影响制造过程中零件的微观结构，因为通常数百万个单独的激光矢量中的每一个都会影响零件的热历史和最终的微观结构。虽然激光功率、扫描速度、舱口间距和层厚等常用参数对零件微观结构的影响已经得到了很好的研究，但对扫描仪延迟（如多边形延迟）的关注却很少。本研究从单个扫描轨迹开始，利用电子后向散射衍射研究了0 ~ 450微秒多边形延迟值引起的微结构变化。然后，该研究将单个轨迹扩展到简单的三维部分，以检查多边形延迟引起的微观结构差异是否可能受到附近舱口矢量和连续层引起的局部加热和冷却的影响。结果表明，在单个扫描轨迹中，不同的多边形延迟明显影响晶粒形态，尽管这些影响在三维构建期间不太明显。未来的PBF-LB/M研究应更多地关注时间分辨激光束加工效果，以更好地减少不一致，提高零件质量。

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引用次数: 0