Additive manufacturing letters最新文献_第10页

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 Epub Date: 2025-04-07 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

Microstructure-sensitive mechanical behavior of an additively manufactured psuedoelastic shape memory alloy 增材制造伪弹性形状记忆合金的微结构敏感力学行为

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-04-01 Epub Date: 2025-01-28 DOI: 10.1016/j.addlet.2025.100270

Patxi Fernandez-Zelaia , Chris Ledford , Chris M. Fancher , Sarah Graham , Taresh Guleria , Brad Sampson , Fred List III , Jason Mayeur , Chins Chinnasamy , Mohammad Elahinia , Michael M. Kirka

The additive manufacturing of shape memory alloys into complex geometries enables fabrication of advanced functional systems across a variety of fields and domains. This work presents results focused on the mechanical behavior of additively manufactured shape memory pseudoelastic NiTi. The deformation induced solid state phase transformation from austenite to martensite allows this system to accommodate large recoverable strains. This deformation behavior is fundamentally driven by crystal-scale transformation physics. Laser powder bed fusion processing reveals that the resulting microstructure, both grain morphology and crystallographic texture, is strongly dependent on the manufacturing processing history. Exhaustive mechanical testing demonstrates that these microstructural factors strongly impact both tensile and cyclic stress–strain behavior. Cyclic dissipative behavior, however, is similar across all tested microstructures following an initial transient period. Remarkably, analysis of spatial strain fields during tensile loading reveals two distinctly different localization “modes”. The first is initiation of localized deformation bands which continuously propagate through the tensile bar during loading. In the second mode localization is observed but lacks propagation; instead additional localization cites nucleate during subsequent loading. The latter phenomena is suspected to be driven by grain-scale deformation physics as the localized band morphologies coincide with grain morphologies. These phenomena strongly impact the resulting aggregate stress–strain behavior. Hence, manufacturers and designers of psuedoelastic functional components must at the very least consider the potential variability in properties when considering additive manufacturing processing. More ideally the process–structure–property relations can be used to further tailor and optimize final functional performance.

形状记忆合金的复杂几何形状的增材制造使制造跨越各种领域和领域的先进功能系统成为可能。本工作提出的结果集中在增材制造的形状记忆伪弹性NiTi的力学行为。变形引起的固态相变从奥氏体到马氏体，使该体系能够适应大的可恢复应变。这种变形行为基本上是由晶体尺度变换物理驱动的。激光粉末床熔合加工表明，所得到的微观组织，无论是晶粒形貌还是晶体织构，都强烈依赖于制造加工历史。详尽的力学测试表明，这些微观结构因素强烈影响拉伸和循环应力-应变行为。然而，在初始瞬态期之后，所有测试的微观结构的循环耗散行为是相似的。值得注意的是，拉伸加载过程中的空间应变场分析揭示了两种明显不同的局部化“模式”。首先是加载过程中通过拉伸杆连续传播的局部变形带的产生。在第二种模式中，观察到局域化，但缺乏传播；相反，在随后的加载过程中，额外的局部化会形成核。后一种现象被怀疑是由晶粒形变物理驱动的，因为局域带的形貌与晶粒形貌一致。这些现象强烈地影响了最终的总应力-应变行为。因此，在考虑增材制造工艺时，伪弹性功能部件的制造商和设计师至少必须考虑性能的潜在可变性。更理想的是，过程-结构-性能关系可以用来进一步定制和优化最终的功能性能。

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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 : 2025-04-01 Epub 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

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 Epub Date: 2025-03-29 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

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 : 2025-04-01 Epub 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

Study on metallurgical interface and grain refinement effect in AlMgSc alloy reinforced with HEAs particles formed by arc-direct energy deposition 电弧直接能量沉积HEAs颗粒增强AlMgSc合金的冶金界面及晶粒细化效果研究

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-04-01 Epub Date: 2025-01-20 DOI: 10.1016/j.addlet.2025.100271

Shihao Shi, Yingying Ren, Shihao Kang, Yongqin Liu, Chenyu Liu, Yaning He, Yinghui Zhou

On the basis of the AlMgSc alloy formed by Arc-DED (Arc Directed Energy Deposition), we adopted a method of coaxially depositing powder and wire layer by layer to fabricate the AlMgSc alloy enhanced by (HEAs) High Entropy Alloys. The HEAs powder exhibited favorable metallurgical bonding with the α-Al matrix, and the elements such as Co, Fe, and Ni in the HEAs particles obviously diffused towards the matrix at the interface. The addition of HEAs powder significantly refined the microstructure. The average grain size of the AlMgSc alloy was 40.7 ± 13.9 μm, while that of the AlMgSc-HEAs alloy was 14.5 ± 4.9 μm, with a 64 % reduction in grain size. Compared with the AlMgSc alloy, the yield strength (YS) of the AlMgSc-HEAs alloy was increased by 9 %.

在电弧定向能沉积法（Arc - ded）制备AlMgSc合金的基础上，采用一层一层同轴沉积粉末和线材的方法制备了HEAs高熵合金增强AlMgSc合金。HEAs粉末与α-Al基体表现出良好的冶金结合，颗粒中的Co、Fe、Ni等元素在界面处明显向基体扩散。HEAs粉末的加入显著改善了显微组织。AlMgSc合金的平均晶粒尺寸为40.7±13.9 μm， AlMgSc- heas合金的平均晶粒尺寸为14.5±4.9 μm，晶粒尺寸减小了64%。与AlMgSc合金相比，AlMgSc- heas合金的屈服强度提高了9%。

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 Epub Date: 2025-04-12 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

Comparative analysis of machining and electropolishing for surface quality improvement of shape memory nitinol samples additively manufactured by laser powder bed fusion 激光粉末床熔合增材加工改善形状记忆镍钛诺表面质量的比较分析

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-02-01 Epub Date: 2024-12-18 DOI: 10.1016/j.addlet.2024.100261

Rodrigo Zapata Martínez , Shohom Bose-Bandyopadhyay , Alan Burl , Óscar Contreras-Almengor , Carlos Aguilar Vega , Kyle Saleeby , Thomas Kurfess , Andrés Díaz Lantada , Jon Molina-Aldareguia

Nickel-titanium (NiTi) or nitinol alloys exhibit high corrosion resistance, mechanical strength, biocompatibility, and smart properties, rendering them ideal materials for active biomedical devices. Traditional manufacturing techniques struggle with these alloys, prompting the adoption of Laser Powder Bed Fusion (L-PBF) as a viable alternative for producing geometrically challenging features. However, L-PBF inherently introduces geometric inconsistencies and surface defects, necessitating post-processing. Electropolishing and chemical etching, while effective for surface smoothing, result in non-conformal material removal, potentially altering the designed geometry. This study examines the use of machining as a post-processing method to achieve uniform material removal and maintain geometric fidelity. Planar spring-shaped actuators were fabricated via L-PBF and subsequently machined to their final geometry using a Computer Numerical Controlled (CNC) system. The actuators were assessed for geometric accuracy and shape memory properties. Machining of the actuators lead to a near homogeneous thickness of 300 µm in all cases, whereas the electropolished + chemically etched samples varied dramatically from <50 µm to over 400 µm in thickness. The findings demonstrate that CNC machining effectively enhances the geometric precision of L-PBF-manufactured NiTi components, while preserving shape memory characteristics. This research underscores the potential of integrating L-PBF with CNC machining to improve the precision and functionality of NiTi-based biomedical devices.

镍钛（NiTi）或镍钛诺合金具有高耐腐蚀性，机械强度，生物相容性和智能性能，使其成为活性生物医学设备的理想材料。传统的制造技术与这些合金相斗争，促使采用激光粉末床融合（L-PBF）作为生产具有几何挑战性特征的可行替代方案。然而，L-PBF固有地引入几何不一致和表面缺陷，需要后处理。电抛光和化学蚀刻虽然对表面光滑有效，但会导致非保形材料的去除，可能会改变设计的几何形状。本研究考察了使用加工作为后处理方法，以实现均匀的材料去除和保持几何保真度。平面弹簧形驱动器通过L-PBF制造，随后使用计算机数控（CNC）系统加工成最终几何形状。评估了执行器的几何精度和形状记忆性能。在所有情况下，执行器的加工厚度几乎均匀，为300 μ m，而电抛光+化学蚀刻样品的厚度从50 μ m到400 μ m以上变化很大。研究结果表明，数控加工有效地提高了l - pbf制造的NiTi零件的几何精度，同时保持了形状记忆特性。这项研究强调了将L-PBF与CNC加工相结合的潜力，以提高基于niti的生物医学设备的精度和功能。

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引用次数: 0

Micro-X-ray-CT for analysis of particle size segregation during powder spreading in Binder Jet Printing 用微x射线ct分析粘合剂喷射印刷中粉末扩散过程中的粒度偏析

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-02-01 Epub Date: 2025-01-04 DOI: 10.1016/j.addlet.2024.100266

Julia G. Behnsen , Joseph W. Roberts , Oliver J. Rogan , James M. McArdle , Kate Black

The uniformity of the powder bed in Binder Jet Printing can impact the final properties of additively manufactured components. Granular flow phenomena, such as particle size segregation can influence the uniformity of the powder bed. Due to the 3D nature of the powder bed and the standard requirement for sintering parts following printing, direct experimental observation of the particle distribution and packing density can be difficult. The use of Micro-X-ray-CT however, enables the high-resolution imaging of components manufactured by binder jetting and allows quantification of particle size distribution and packing density throughout the powder bed. This study analyses the periodicity of effects such as in-layer particles size segregation and packing density. The results presented here show that particles segregate by size within each layer of the binder jet printed sample, which resulted in a periodic density change within each layer. The particle size distribution changes over the length of the power-bed, with the volume fraction of smaller particles increased near the front of the powder bed, and the volume fraction of larger particles increased near the back. The insights gained from the Micro-X-ray-CT characterisation approach allow for an enhanced understanding of the powder spreading process in additive manufacturing, paving the way forward for possible part optimisation.

粘合剂喷射印刷中粉末床的均匀性会影响快速成型部件的最终性能。粒度偏析等颗粒流动现象会影响粉末床的均匀性。由于粉末床的三维性质和打印后部件烧结的标准要求，很难对颗粒分布和堆积密度进行直接实验观察。然而，使用 Micro-X 射线-计算机断层扫描可以对通过粘合剂喷射制造的部件进行高分辨率成像，并对整个粉末床的粒度分布和堆积密度进行量化。本研究分析了层内颗粒尺寸偏析和堆积密度等效应的周期性。研究结果表明，在粘合剂喷射打印的样品中，每层内的颗粒都会发生尺寸偏析，从而导致每层内的密度发生周期性变化。颗粒尺寸分布在粉末床的长度方向上发生变化，较小颗粒的体积分数在靠近粉末床前部的位置增加，而较大颗粒的体积分数在靠近粉末床后部的位置增加。从显微 X 射线-计算机断层扫描表征方法中获得的启示有助于加深对增材制造中粉末铺展过程的理解，为可能的零件优化铺平道路。

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引用次数: 0

Resin-dependent mechanical anisotropy in laser vat photopolymerization correlates to the initial rate of polymerization and critical energy 激光还原光聚合过程中树脂相关的力学各向异性与初始聚合速率和临界能有关

IF 4.2 Q2 ENGINEERING, MANUFACTURING

Additive manufacturing letters

Pub Date : 2025-02-01 Epub Date: 2024-12-25 DOI: 10.1016/j.addlet.2024.100264

Dagoberto Torres-Alvarez, Angel Celis-Guzman, Alan Aguirre-Soto

The degree of mechanical anisotropy in objects printed with laser vat photopolymerization (VPP) remains controversial. It has been stated that objects with a higher degree of mechanical isotropy are produced with VPP as compared to other polymer-based additive manufacturing techniques, such as fused filament fabrication (FFF). However, reports on the evaluation of resin-dependency of the mechanical anisotropy obtained with VPP are scarce. Furthermore, the degree of anisotropy (DA) was quantified using different procedures. Here, six commercial resins were selected to evaluate how the DA correlates to the initial rate of polymerization (R_P0), critical energy (E_C), and penetration depth (D_P) for materials with a broader range of properties. State-of-the-art procedures to calculate the degree of mechanical anisotropy are discussed, and an ideal method is proposed, namely, the ratio of the standard deviations related to the inter- and intra-layer forces: DA=(sd_inter/sd_intra). The elastic modulus (E) was confirmed isotropic with the three resins that were previously reported. However, objects printed with the additional resins that polymerize at higher initial rates (R_P0 =72.1 mM/s) and with lower critical energies (E_C = 0.36 mJ/cm²) appear more anisotropic. A linear trend was obtained for the scaling of the mechanical DA with R_P0. Moreover, a logarithmic correlation between E_C and the DA in E was found, which appears inappropriate for E_C as a function of the DA in the maximum stress (σ_Max). This study aims to spur research on the mechanisms underlying the dependence of the mechanical DA on the resin-curing behavior for objects fabricated by VPP.

激光还原光聚合（VPP）打印物体的力学各向异性程度仍然存在争议。与其他基于聚合物的增材制造技术（如熔丝制造（FFF））相比，用VPP生产具有更高机械各向同性程度的物体。然而，关于VPP获得的力学各向异性的树脂依赖性评价的报道很少。此外，采用不同的方法对各向异性程度（DA）进行了量化。在这里，选择了六种商业树脂来评估DA如何与具有更广泛性质的材料的初始聚合速率（r0），临界能量（EC）和渗透深度（DP）相关。讨论了计算力学各向异性程度的最新方法，并提出了一种理想的方法，即与层间力和层内力相关的标准差之比：DA=(sdinter/sdintra)。弹性模量(E)与之前报道的三种树脂确认各向同性。然而，用更高初始聚合速率（r0 =72.1 mM/s）和更低临界能量（EC = 0.36 mJ/cm2）的额外树脂打印的物体表现出更多的各向异性。机械DA的标度随r0呈线性变化趋势。此外，E中EC与DA呈对数相关，不适合将EC作为最大应力（σMax）中DA的函数。本研究旨在促进对机械DA对VPP材料树脂固化行为依赖机制的研究。

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引用次数: 0