Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104541
Syed Bustan Fatima Warsi , Biranchi Panda , Pankaj Biswas
This study presents a promising approach of integrating coarse aggregates and steel fibers (smooth straight and corrugated) into 3D printed concrete to enhance both strain-hardening and ductility properties. The research delves into the engineering design of fiber reinforced 3D printed concrete by analysing the effect of critical fiber volume and coarse aggregate addition on concrete tensile properties. The combination of coarse aggregate and fiber enhances the material ability to withstand increasing loads by promoting plastic deformation, while mitigating the crack formation and propagation. Experimental methodology for engineering design of fiber reinforced 3D printed concrete is elucidated via critical fiber volume analysis, strain hardening analysis, and ductility assessment under direct tensile loading. The results indicate synergistic effect of corrugated fibers and coarse aggregates on the tensile properties and unlike straight smooth fiber, corrugated long fibers significantly contribute to excellent strain hardening behaviour. The new 3D printed concrete composite developed in this study exhibited distinctive yield point with high strain hardening factor (1.62), ductile factor (10.86), and enhanced energy absorption capability (+105 kJ/m³). These enhanced properties make the material particularly suitable for applications in seismic-resistant structures and other load-bearing applications where ductility and energy absorption are critical.
本研究提出了一种将粗骨料和钢纤维(光滑的直纤维和波纹纤维)融入三维打印混凝土以增强应变硬化和延展性能的可行方法。研究通过分析临界纤维量和粗骨料添加量对混凝土拉伸性能的影响,深入探讨了纤维增强 3D 打印混凝土的工程设计。粗骨料和纤维的组合通过促进塑性变形增强了材料承受载荷增加的能力,同时缓解了裂缝的形成和扩展。通过临界纤维量分析、应变硬化分析和直接拉伸加载下的延性评估,阐明了纤维增强 3D 打印混凝土工程设计的实验方法。结果表明,波纹纤维和粗集料对拉伸性能有协同作用,与直的光滑纤维不同,波纹长纤维能显著促进优异的应变硬化性能。本研究中开发的新型 3D 打印混凝土复合材料具有独特的屈服点、高应变硬化因子(1.62)、延展因子(10.86)和更强的能量吸收能力(+105 kJ/m³)。这些增强的特性使该材料特别适合应用于抗震结构和其他对延展性和能量吸收至关重要的承重应用领域。
{"title":"Development of ultra-ductile strain hardening 3D printed concrete composite utilizing critical fiber volume and coarse aggregate","authors":"Syed Bustan Fatima Warsi , Biranchi Panda , Pankaj Biswas","doi":"10.1016/j.addma.2024.104541","DOIUrl":"10.1016/j.addma.2024.104541","url":null,"abstract":"<div><div>This study presents a promising approach of integrating coarse aggregates and steel fibers (smooth straight and corrugated) into 3D printed concrete to enhance both strain-hardening and ductility properties. The research delves into the engineering design of fiber reinforced 3D printed concrete by analysing the effect of critical fiber volume and coarse aggregate addition on concrete tensile properties. The combination of coarse aggregate and fiber enhances the material ability to withstand increasing loads by promoting plastic deformation, while mitigating the crack formation and propagation. Experimental methodology for engineering design of fiber reinforced 3D printed concrete is elucidated via critical fiber volume analysis, strain hardening analysis, and ductility assessment under direct tensile loading. The results indicate synergistic effect of corrugated fibers and coarse aggregates on the tensile properties and unlike straight smooth fiber, corrugated long fibers significantly contribute to excellent strain hardening behaviour. The new 3D printed concrete composite developed in this study exhibited distinctive yield point with high strain hardening factor (1.62), ductile factor (10.86), and enhanced energy absorption capability (+105 kJ/m³). These enhanced properties make the material particularly suitable for applications in seismic-resistant structures and other load-bearing applications where ductility and energy absorption are critical.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104541"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663900","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104503
Peter Pak , Francis Ogoke , Andrew Polonsky , Anthony Garland , Dan S. Bolintineanu , Dan R. Moser , Mary Arnhart , Jonathan Madison , Thomas Ivanoff , John Mitchell , Bradley Jared , Brad Salzbrenner , Michael J. Heiden , Amir Barati Farimani
Part qualification is often a critical and labor-intensive process in additive manufacturing, particularly in the detection of defects such as porosity, which stands to benefit significantly from advancements in machine learning. We present a deep learning approach for quantifying and localizing ex-situ porosity within Laser Powder Bed Fusion fabricated samples utilizing in-situ thermal image monitoring data. Our goal is to build the real time porosity map of parts based on thermal images acquired during the build. The quantification task builds upon the established Convolutional Neural Network model architecture to predict pore count and the localization task leverages the spatial and temporal attention mechanisms of the novel Video Vision Transformer model to indicate areas of expected porosity. Our model for porosity quantification achieved a score of 0.57 and our model for porosity localization produced an average Intersection over Union (IoU) score of 0.32 and a maximum of 1.0. This work is setting the foundations of part porosity “Digital Twins” based on additive manufacturing monitoring data and can be applied downstream to reduce time-intensive post-inspection and testing activities during part qualification and certification. In addition, we seek to accelerate the acquisition of crucial insights normally only available through ex-situ part evaluation by means of machine learning analysis of in-situ process monitoring data.
{"title":"ThermoPore: Predicting part porosity based on thermal images using deep learning","authors":"Peter Pak , Francis Ogoke , Andrew Polonsky , Anthony Garland , Dan S. Bolintineanu , Dan R. Moser , Mary Arnhart , Jonathan Madison , Thomas Ivanoff , John Mitchell , Bradley Jared , Brad Salzbrenner , Michael J. Heiden , Amir Barati Farimani","doi":"10.1016/j.addma.2024.104503","DOIUrl":"10.1016/j.addma.2024.104503","url":null,"abstract":"<div><div>Part qualification is often a critical and labor-intensive process in additive manufacturing, particularly in the detection of defects such as porosity, which stands to benefit significantly from advancements in machine learning. We present a deep learning approach for quantifying and localizing <em>ex-situ</em> porosity within Laser Powder Bed Fusion fabricated samples utilizing <em>in-situ</em> thermal image monitoring data. Our goal is to build the real time porosity map of parts based on thermal images acquired during the build. The quantification task builds upon the established Convolutional Neural Network model architecture to predict pore count and the localization task leverages the spatial and temporal attention mechanisms of the novel Video Vision Transformer model to indicate areas of expected porosity. Our model for porosity quantification achieved a <span><math><msup><mrow><mtext>R</mtext></mrow><mrow><mn>2</mn></mrow></msup></math></span> score of 0.57 and our model for porosity localization produced an average Intersection over Union (IoU) score of 0.32 and a maximum of 1.0. This work is setting the foundations of part porosity “Digital Twins” based on additive manufacturing monitoring data and can be applied downstream to reduce time-intensive post-inspection and testing activities during part qualification and certification. In addition, we seek to accelerate the acquisition of crucial insights normally only available through <em>ex-situ</em> part evaluation by means of machine learning analysis of <em>in-situ</em> process monitoring data.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104503"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663997","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104546
Jiaqiang Chang , Yingjie Ma , Sensen Huang , Min Qi , Zirong Zhai , Yingna Wu , Rui Yang , Zhenbo Zhang
Conventional titanium alloys have a high propensity in developing columnar grains with strong textures during additive manufacturing (AM), which causes pronounced anisotropy in mechanical properties and hampers their practical applications. In this study, a new metastable β titanium alloy with high Fe addition (Ti-3Al-6Fe-6V-2Zr, wt%) was designed for AM, and the strategies and underlying mechanisms to eliminating the structural heterogeneity including grain morphology, Fe element segregation and phase constituent distribution were elaborately investigated. It was demonstrated that the alloy has an outstanding intrinsic capability of forming equiaxed grains during direct energy deposition (DED) due to the positive effect of Fe on constitutional supercooling. The final microstructure of bulk sample was determined by the directly deposited microstructure and subsequent microstructure coarsening caused by cyclic heating, and homogeneously equiaxed microstructure without texture could be achieved when the heat-affected zones can fully cover the formerly deposited layer. Despite of very high level of Fe addition, both microscale and macroscale Fe segregation were completely suppressed during DED, by taking the advantages of fast solidification rate and tailoring the heating effect between the adjacent layers. Moreover, the problem related to the heterogeneity in α phase distribution along the building direction was solved by mitigating the heat accumulation during DED. On the basis of these understandings, homogeneously equiaxed Ti3662 alloy with isotropic mechanical properties of high strength (∼1200 MPa) and decent ductility (∼10 %) was finally fabricated by DED, which stands a good chance for practical application. This study demonstrates that the special metallurgical process during AM largely expands the design space of titanium alloys on the aspects of composition and microstructure, which can be utilized to fabricate titanium alloys with desirable microstructure and excellent properties.
{"title":"Additive manufacturing of a new titanium alloy with tunable microstructure and isotropic properties","authors":"Jiaqiang Chang , Yingjie Ma , Sensen Huang , Min Qi , Zirong Zhai , Yingna Wu , Rui Yang , Zhenbo Zhang","doi":"10.1016/j.addma.2024.104546","DOIUrl":"10.1016/j.addma.2024.104546","url":null,"abstract":"<div><div>Conventional titanium alloys have a high propensity in developing columnar grains with strong textures during additive manufacturing (AM), which causes pronounced anisotropy in mechanical properties and hampers their practical applications. In this study, a new metastable β titanium alloy with high Fe addition (Ti-3Al-6Fe-6V-2Zr, wt%) was designed for AM, and the strategies and underlying mechanisms to eliminating the structural heterogeneity including grain morphology, Fe element segregation and phase constituent distribution were elaborately investigated. It was demonstrated that the alloy has an outstanding intrinsic capability of forming equiaxed grains during direct energy deposition (DED) due to the positive effect of Fe on constitutional supercooling. The final microstructure of bulk sample was determined by the directly deposited microstructure and subsequent microstructure coarsening caused by cyclic heating, and homogeneously equiaxed microstructure without texture could be achieved when the heat-affected zones can fully cover the formerly deposited layer. Despite of very high level of Fe addition, both microscale and macroscale Fe segregation were completely suppressed during DED, by taking the advantages of fast solidification rate and tailoring the heating effect between the adjacent layers. Moreover, the problem related to the heterogeneity in α phase distribution along the building direction was solved by mitigating the heat accumulation during DED. On the basis of these understandings, homogeneously equiaxed Ti3662 alloy with isotropic mechanical properties of high strength (∼1200 MPa) and decent ductility (∼10 %) was finally fabricated by DED, which stands a good chance for practical application. This study demonstrates that the special metallurgical process during AM largely expands the design space of titanium alloys on the aspects of composition and microstructure, which can be utilized to fabricate titanium alloys with desirable microstructure and excellent properties.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104546"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663899","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104537
Tangsiyuan Zhang, Xinyu Cao, Shuming Zhang, Yuhang Chen, YeTing Huang, Min Yu, Xiaoyu Han
Top-down vat photopolymerization (TVPP) technology is rapidly developing to all of the industries for new products development and manufacturing due to its low cost, fast speed and high precision. The powerful capability of TVPP for large size, highly customized and medium batch production renders it one of the most popular additive manufacturing techniques today. An effective real-time process monitoring method providing timely feedback for part defects, especially in case of print failure, is highly desirable but still rarely reported for TVPP 3D printing. Large 3D objects are normally segmented into smaller parts to reduce the risk of failure and materials waste, resulting in the complexity of building while sacrificing component integrity. Herein, a transformer neural network based real-time and visualized process monitoring (TransRV) was constructed as an effective method to enhance the manufacturing performance and quality. Upon the challenge of visualizing and capturing the real-time fabricated layer from the around liquid photoresin, a real-time dataset including in-situ standard reference images and real-time mask fabricated layers was initially constructed. Based on the dataset foundation, we then developed a novel neural network model for effective segmentation of captured images by introducing multiple attention mechanisms and adopting the architecture of Swin Transformer. The experimental results showed that the real-time taken images during the printing process could be accurately segmented through our designed neural network model. The mIoU, which is the ratio of mean intersection over union, was considered as the main evaluation index in the test set. And the value of mIoU could achieve as high as 96.14 %. On the basis of this result, we further constructed a multiple quality monitoring indicator for quality assessment and defect detection of TVPP process. It was proved that this indicator enabled real-time accurate recognition and in time feedback. The typical defects such as overall collapse and partial missing of the printed parts that usually occur during TVPP process would be timely detected and subsequently stopped printing. Apparently, the methods developed in this work provide a promising strategy to effectively eliminate the material waste and highly improve the productivity. Most importantly, the presented real-time process monitor holds the great potential for quality control and defect detection of widespread TVPP manufacturing.
{"title":"Transformer neural network based real-time process monitoring and direct visualization of top-down vat photopolymerization","authors":"Tangsiyuan Zhang, Xinyu Cao, Shuming Zhang, Yuhang Chen, YeTing Huang, Min Yu, Xiaoyu Han","doi":"10.1016/j.addma.2024.104537","DOIUrl":"10.1016/j.addma.2024.104537","url":null,"abstract":"<div><div>Top-down vat photopolymerization (TVPP) technology is rapidly developing to all of the industries for new products development and manufacturing due to its low cost, fast speed and high precision. The powerful capability of TVPP for large size, highly customized and medium batch production renders it one of the most popular additive manufacturing techniques today. An effective real-time process monitoring method providing timely feedback for part defects, especially in case of print failure, is highly desirable but still rarely reported for TVPP 3D printing. Large 3D objects are normally segmented into smaller parts to reduce the risk of failure and materials waste, resulting in the complexity of building while sacrificing component integrity. Herein, a transformer neural network based real-time and visualized process monitoring (TransRV) was constructed as an effective method to enhance the manufacturing performance and quality. Upon the challenge of visualizing and capturing the real-time fabricated layer from the around liquid photoresin, a real-time dataset including in-situ standard reference images and real-time mask fabricated layers was initially constructed. Based on the dataset foundation, we then developed a novel neural network model for effective segmentation of captured images by introducing multiple attention mechanisms and adopting the architecture of Swin Transformer. The experimental results showed that the real-time taken images during the printing process could be accurately segmented through our designed neural network model. The mIoU, which is the ratio of mean intersection over union, was considered as the main evaluation index in the test set. And the value of mIoU could achieve as high as 96.14 %. On the basis of this result, we further constructed a multiple quality monitoring indicator for quality assessment and defect detection of TVPP process. It was proved that this indicator enabled real-time accurate recognition and in time feedback. The typical defects such as overall collapse and partial missing of the printed parts that usually occur during TVPP process would be timely detected and subsequently stopped printing. Apparently, the methods developed in this work provide a promising strategy to effectively eliminate the material waste and highly improve the productivity. Most importantly, the presented real-time process monitor holds the great potential for quality control and defect detection of widespread TVPP manufacturing.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104537"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663999","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104544
Pooja Srinivas , Liya Jacob , C. Muhammed Shebeeb , Haider Butt , Imad Barsoum , Rashid K. Abu Al-Rub , Wael Zaki
Electromagnetic interference (EMI) shielding is vital in safeguarding electronic devices from the harmful effects of external electromagnetic signals, a critical factor in ensuring the reliability and functionality of these systems. EMI, originating from a myriad of sources, can range from causing temporary disruptions to catastrophic system failures and potentially harmful consequences. This study delves into the EMI shielding capabilities of 3D printed Polyvinylidene Fluoride (PVDF)-graphene Triply Periodic Minimal Surface (TPMS) structures, fabricated using Material Extrusion (ME) process. The focus on TPMS structures stems from their unique geometrical configurations, offering promising potentials in enhancing EMI shielding effectiveness. Four distinct TPMS topologies—gyroid, Neovius, diamond, and I-WP were explored, with each demonstrating varying degrees of shielding effectiveness. 3D printed solid samples showed an average specific shielding effectiveness (SSE) of 13 dB cm3/g, and Neovius triply periodic minimal surface (TPMS) structure exhibited an average SSE of 94 dB cm3/g. Absolute shielding effectiveness (SSE/t) for solid samples and Neovius TPMS structure is around 66 dB cm2/g and 62.5 dB cm2/g respectively. Among the tested samples, those with a Neovius topology emerged as particularly promising, exhibiting high EMI shielding effectiveness suitable for commercial applications. Furthermore, the study investigates the impact of several design and printing parameters, including relative density/infill percentage, print orientation, and the size of unit cells, on total shielding effectiveness (SET). Results revealed SET variations ranging between 25 dB and 75 dB, suggesting that tuning the SET of these samples is feasible by adjusting these parameters. The study's findings, highlighting a strong correlation between SET and frequency influenced by unique geometrical characteristics and frequency-dependent interactions, underscore the potential of architected PVDF-graphene TPMS structures in EMI shielding applications. This opens new avenues for research and development in this field, paving the way for more advanced and effective EMI shielding solutions.
电磁干扰(EMI)屏蔽对于保护电子设备免受外部电磁信号的有害影响至关重要,是确保这些系统可靠性和功能性的关键因素。电磁干扰的来源多种多样,既可能造成暂时性中断,也可能导致灾难性的系统故障和潜在的有害后果。本研究深入探讨了使用材料挤压(ME)工艺制造的三维打印聚偏二氟乙烯(PVDF)-石墨烯三周期最小表面(TPMS)结构的电磁干扰屏蔽能力。对 TPMS 结构的关注源于其独特的几何配置,在增强 EMI 屏蔽效果方面具有广阔的潜力。研究人员探索了四种不同的 TPMS 拓扑结构--gyroid、Neovius、diamond 和 I-WP,每种拓扑结构都显示出不同程度的屏蔽效果。三维打印实体样品的平均特定屏蔽效能(SSE)为 13 dB cm3/g,Neovius 三周期最小表面(TPMS)结构的平均 SSE 为 94 dB cm3/g。固体样品和 Neovius TPMS 结构的绝对屏蔽效能(SSE/t)分别约为 66 dB cm2/g 和 62.5 dB cm2/g。在测试的样品中,采用 Neovius 拓扑结构的样品尤其具有发展前景,其 EMI 屏蔽效果很高,适合商业应用。此外,该研究还调查了几个设计和印刷参数对总屏蔽效能(SET)的影响,包括相对密度/填充百分比、印刷方向和单元尺寸。结果显示,SET 的变化范围在 25 dB 到 75 dB 之间,这表明通过调整这些参数来调整这些样品的 SET 是可行的。这项研究的发现强调了 SET 与频率之间受独特几何特性和频率依赖性相互作用影响的密切联系,凸显了结构化 PVDF 石墨烯 TPMS 结构在 EMI 屏蔽应用中的潜力。这为该领域的研究和开发开辟了新途径,为更先进、更有效的 EMI 屏蔽解决方案铺平了道路。
{"title":"Effect of printing parameters and triply periodic minimal surfaces on electromagnetic shielding efficiency of polyvinylidene fluoride graphene nanocomposites","authors":"Pooja Srinivas , Liya Jacob , C. Muhammed Shebeeb , Haider Butt , Imad Barsoum , Rashid K. Abu Al-Rub , Wael Zaki","doi":"10.1016/j.addma.2024.104544","DOIUrl":"10.1016/j.addma.2024.104544","url":null,"abstract":"<div><div>Electromagnetic interference (EMI) shielding is vital in safeguarding electronic devices from the harmful effects of external electromagnetic signals, a critical factor in ensuring the reliability and functionality of these systems. EMI, originating from a myriad of sources, can range from causing temporary disruptions to catastrophic system failures and potentially harmful consequences. This study delves into the EMI shielding capabilities of 3D printed Polyvinylidene Fluoride (PVDF)-graphene Triply Periodic Minimal Surface (TPMS) structures, fabricated using Material Extrusion (ME) process. The focus on TPMS structures stems from their unique geometrical configurations, offering promising potentials in enhancing EMI shielding effectiveness. Four distinct TPMS topologies—gyroid, Neovius, diamond, and I-WP were explored, with each demonstrating varying degrees of shielding effectiveness. 3D printed solid samples showed an average specific shielding effectiveness (SSE) of 13 dB cm<sup>3</sup>/g, and Neovius triply periodic minimal surface (TPMS) structure exhibited an average SSE of 94 dB cm<sup>3</sup>/g. Absolute shielding effectiveness (SSE/t) for solid samples and Neovius TPMS structure is around 66 dB cm<sup>2</sup>/g and 62.5 dB cm<sup>2</sup>/g respectively. Among the tested samples, those with a Neovius topology emerged as particularly promising, exhibiting high EMI shielding effectiveness suitable for commercial applications. Furthermore, the study investigates the impact of several design and printing parameters, including relative density/infill percentage, print orientation, and the size of unit cells, on total shielding effectiveness (SE<sub>T</sub>). Results revealed SE<sub>T</sub> variations ranging between 25 dB and 75 dB, suggesting that tuning the SE<sub>T</sub> of these samples is feasible by adjusting these parameters. The study's findings, highlighting a strong correlation between SE<sub>T</sub> and frequency influenced by unique geometrical characteristics and frequency-dependent interactions, underscore the potential of architected PVDF-graphene TPMS structures in EMI shielding applications. This opens new avenues for research and development in this field, paving the way for more advanced and effective EMI shielding solutions.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104544"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663894","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104558
Zhenhuan Lv , Wenqiang Yang , Li Yao , Xiang Chen , Junyang Zhou , Ruoyu Li , Hui Mei , Laifei Cheng , Litong Zhang
As a classical ferroelectric material, the BaTiO3-based electromagnetic metamaterials for microwave absorption/shielding have not been investigated. In this paper, triply-periodic minimal surface structures with varied unit cell dimensions (UCD) and relative densities (RD) are firstly constructed to investigate the relationship between macrostructure and electromagnetic response, and the single-step fabrication of BaTiO3-based metamaterial microwave absorber is then achieved by 3D printing technology. The optimal microwave absorption performance with a minimum reflection loss of –59.06 dB and an effective absorption bandwidth of 1.7 GHz is achieved in X-band when the UCD is 1 T (taking the UCD in the direction of microwave incidence 1 T=1.47 mm as the standard, and enlarging the UCD as a whole to 5 T in 1 T steps) and the RD is 10 %. In contrast, when the UCD is 2 T, the total shielding effectiveness of BaTiO3 metamaterial is 15.98 dB, which indicates that the transition from shielding to microwave-absorbing materials can be achieved through the optimization of the macrostructure. This study shows that by tailoring structural parameters, completely different electromagnetic responses can be obtained. Macrostructural design ideas for ferroelectric metamaterials can be explored in more depth based on the above studies.
{"title":"Electromagnetic response mechanism of BaTiO3-based metamaterials: Transition between microwave absorption and shielding capacity","authors":"Zhenhuan Lv , Wenqiang Yang , Li Yao , Xiang Chen , Junyang Zhou , Ruoyu Li , Hui Mei , Laifei Cheng , Litong Zhang","doi":"10.1016/j.addma.2024.104558","DOIUrl":"10.1016/j.addma.2024.104558","url":null,"abstract":"<div><div>As a classical ferroelectric material, the BaTiO<sub>3</sub>-based electromagnetic metamaterials for microwave absorption/shielding have not been investigated. In this paper, triply-periodic minimal surface structures with varied unit cell dimensions (UCD) and relative densities (RD) are firstly constructed to investigate the relationship between macrostructure and electromagnetic response, and the single-step fabrication of BaTiO<sub>3</sub>-based metamaterial microwave absorber is then achieved by 3D printing technology. The optimal microwave absorption performance with a minimum reflection loss of –59.06 dB and an effective absorption bandwidth of 1.7 GHz is achieved in X-band when the UCD is 1 T (taking the UCD in the direction of microwave incidence 1 T=1.47 mm as the standard, and enlarging the UCD as a whole to 5 T in 1 T steps) and the RD is 10 %. In contrast, when the UCD is 2 T, the total shielding effectiveness of BaTiO<sub>3</sub> metamaterial is 15.98 dB, which indicates that the transition from shielding to microwave-absorbing materials can be achieved through the optimization of the macrostructure. This study shows that by tailoring structural parameters, completely different electromagnetic responses can be obtained. Macrostructural design ideas for ferroelectric metamaterials can be explored in more depth based on the above studies.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104558"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663896","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104512
Marvin A. Spurek , Francesco Sillani , Lukas Haferkamp , Enrico Tosoratti , Adriaan B. Spierings , Christopher M. Magazzeni , Martina Meisnar , Konrad Wegener
In laser-based powder bed fusion of metals (PBF-LB/M), the powder layer is the link between the powder properties and the resulting part quality. Powder layer quality is a key metric related to powder spreadability and ultimately part quality, yet it is still unclear how it can be quantified. This is due to the difficulty of studying powder layer properties during the process. This study investigates the influence of powder properties, process parameters, and recoating speed on the surface roughness of the powder layer and the part, as well as on the effective thickness of the powder layer and solidified layer, and the resulting relative part density. Utilizing in-situ laser profilometry, high-resolution topographical data of the powder layer and the part surface were acquired, with minimal interference to the PBF-LB/M process. Six AlSi10Mg powders with varying particle size distribution, morphology, and flowability were processed using a wide range of recoating speeds and scan speeds to create powder layers with a wide range of properties. The results reveal a strong correlation between energy input and the effective powder layer thickness where lower scan speed results in an increased effective powder layer thickness due to material losses. Additionally, faster recoating decreases the powder layer density, which is moderated by the median particle size where the effect is strongest for fine powders. The surface roughness of the powder layer and top part surface are influenced by the recoating speed, energy input, and particle size, and they are strongly linked to each other. This highlights the importance of considering realistic substrate surface roughnesses in both powder spreading experiments and simulations. Finally, layer properties affect the process stability, resulting in small differences in relative part density.
{"title":"Effect of powder properties, process parameters, and recoating speed on powder layer properties measured by in-situ laser profilometry and part properties in laser powder bed fusion","authors":"Marvin A. Spurek , Francesco Sillani , Lukas Haferkamp , Enrico Tosoratti , Adriaan B. Spierings , Christopher M. Magazzeni , Martina Meisnar , Konrad Wegener","doi":"10.1016/j.addma.2024.104512","DOIUrl":"10.1016/j.addma.2024.104512","url":null,"abstract":"<div><div>In laser-based powder bed fusion of metals (PBF-LB/M), the powder layer is the link between the powder properties and the resulting part quality. Powder layer quality is a key metric related to powder spreadability and ultimately part quality, yet it is still unclear how it can be quantified. This is due to the difficulty of studying powder layer properties during the process. This study investigates the influence of powder properties, process parameters, and recoating speed on the surface roughness of the powder layer and the part, as well as on the effective thickness of the powder layer and solidified layer, and the resulting relative part density. Utilizing in-situ laser profilometry, high-resolution topographical data of the powder layer and the part surface were acquired, with minimal interference to the PBF-LB/M process. Six AlSi10Mg powders with varying particle size distribution, morphology, and flowability were processed using a wide range of recoating speeds and scan speeds to create powder layers with a wide range of properties. The results reveal a strong correlation between energy input and the effective powder layer thickness where lower scan speed results in an increased effective powder layer thickness due to material losses. Additionally, faster recoating decreases the powder layer density, which is moderated by the median particle size where the effect is strongest for fine powders. The surface roughness of the powder layer and top part surface are influenced by the recoating speed, energy input, and particle size, and they are strongly linked to each other. This highlights the importance of considering realistic substrate surface roughnesses in both powder spreading experiments and simulations. Finally, layer properties affect the process stability, resulting in small differences in relative part density.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104512"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663897","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}
Multistable metastructures with compression-twist coupling offer promising applications in reusable protective devices, deployable structures and reconfigurable robotics. However, existing designs based on either Kresling origami or truss-based mechanisms, suffer from limited deformability, due to the accumulation of bending deformation in creases or trusses. Herein, we propose a novel multistable twist metastructure by integrating hinged beams with Kresling-inspired trusses. A two-step procedure, combining 3D printing and interlocking assembling, is utilized to fabricate the multistable twist samples. This multistable twist mechanism leverages the elastic instability and shape reconfiguration of hinged beams, enabling transitions between stable configurations with minimal bending in the trusses. This approach achieves exceptional collapsibility with a reusable maximum allowable compression up to 80 % of the structural height. Additionally, the compression-twist coupling of trusses protects hinged beams from severe tensile damage. Furthermore, our strategy offers multidimensional programmability. Geometric design tailors configuration stability (i.e., multi/bistability, monostability, monotonicity), while arraying method controls deformation modes. This culminates in the realization of customized functions of impact resistance and vibration mitigation. Specially, by incorporating trusses, negative stiffness with loop hysteresis can be programmed to enhance energy dissipation, which facilitates to damping the impact and vibration. Experimental tests confirm the compatibility of excellent collapsibility, programmability and multifunctionality. This finding underscores the potential of such multistable metastructure with compression-twist coupling for designing next-generation reusable multifunctional devices.
{"title":"Multistable twist metastructures with enhanced collapsibility and multidimensional programmability","authors":"Peiyuan Zheng, Bin Han, Zhipeng Liu, Qinze Wang, Zeyu Wang, Qi Zhang","doi":"10.1016/j.addma.2024.104550","DOIUrl":"10.1016/j.addma.2024.104550","url":null,"abstract":"<div><div>Multistable metastructures with compression-twist coupling offer promising applications in reusable protective devices, deployable structures and reconfigurable robotics. However, existing designs based on either Kresling origami or truss-based mechanisms, suffer from limited deformability, due to the accumulation of bending deformation in creases or trusses. Herein, we propose a novel multistable twist metastructure by integrating hinged beams with Kresling-inspired trusses. A two-step procedure, combining 3D printing and interlocking assembling, is utilized to fabricate the multistable twist samples. This multistable twist mechanism leverages the elastic instability and shape reconfiguration of hinged beams, enabling transitions between stable configurations with minimal bending in the trusses. This approach achieves exceptional collapsibility with a reusable maximum allowable compression up to 80 % of the structural height. Additionally, the compression-twist coupling of trusses protects hinged beams from severe tensile damage. Furthermore, our strategy offers multidimensional programmability. Geometric design tailors configuration stability (i.e., multi/bistability, monostability, monotonicity), while arraying method controls deformation modes. This culminates in the realization of customized functions of impact resistance and vibration mitigation. Specially, by incorporating trusses, negative stiffness with loop hysteresis can be programmed to enhance energy dissipation, which facilitates to damping the impact and vibration. Experimental tests confirm the compatibility of excellent collapsibility, programmability and multifunctionality. This finding underscores the potential of such multistable metastructure with compression-twist coupling for designing next-generation reusable multifunctional devices.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104550"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663889","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104538
Bianca Maria Colosimo , Federica Garghetti , Marco Grasso , Luca Pagani
As advanced production capabilities are moving towards novel types of geometries as well as higher customization demands, a new and more efficient approach for process and part qualification is becoming an urgent need in industry. The layerwise nature of additive manufacturing (AM) potentially allows anticipating qualification tasks in-line and in-process, aiming at reducing the time and costs devoted to post-process inspections, enabling at the same time an early detection of defects since their onset stage. Such opportunity is particularly attractive in the presence of highly complex shapes like lattice structures or metamaterials, which have been increasingly investigated for industrial adoption in various sectors, aiming to achieve enhanced mechanical properties and innovative functionalities. This paper presents a novel methodology to inspect the geometry of lattice structures while the part is being built. The method is specifically designed to tackle the natural variability affecting layerwise images gathered in laser powder bed fusion. To this aim, it combines the segmentation of in-situ powder bed images of solidified layers with a data modelling approach to synthesize the 3-D shape of each unit cell into a 1-D profile representation. Such low-dimensional representation is suitable to quickly detect undesired distortions that may have a detrimental impact on final quality and performance. By using post-process X-ray computed tomography as ground truth reference, this study shows the effectiveness of the proposed approach for in-line inspection, opening a novel and cost-efficient way to address complex shape qualification for lattice structures in AM.
由于先进的生产能力正朝着新型几何形状和更高定制化要求的方向发展,工业界迫切需要一种新的、更有效的工艺和零件鉴定方法。增材制造(AM)的分层特性使其有可能预测在线和过程中的鉴定任务,从而减少用于过程后检测的时间和成本,同时在缺陷出现阶段就能对其进行早期检测。这种机会对于晶格结构或超材料等高度复杂的形状尤其具有吸引力,这些形状越来越多地被研究用于各个领域的工业应用,旨在实现更强的机械性能和创新功能。本文介绍了一种在零件制造过程中检测晶格结构几何形状的新方法。该方法专门用于解决影响激光粉末床融合过程中收集的层间图像的自然变化问题。为此,它将凝固层的原位粉末床图像分割与数据建模方法相结合,将每个单元格的三维形状合成为一维轮廓表示。这种低维表示法适用于快速检测可能对最终质量和性能产生不利影响的不良变形。通过使用后处理 X 射线计算机断层扫描作为地面实况参考,本研究显示了所建议的在线检测方法的有效性,为解决 AM 中晶格结构复杂的形状鉴定问题开辟了一种新颖且具有成本效益的方法。
{"title":"On-line inspection of lattice structures and metamaterials via in-situ imaging in additive manufacturing","authors":"Bianca Maria Colosimo , Federica Garghetti , Marco Grasso , Luca Pagani","doi":"10.1016/j.addma.2024.104538","DOIUrl":"10.1016/j.addma.2024.104538","url":null,"abstract":"<div><div>As advanced production capabilities are moving towards novel types of geometries as well as higher customization demands, a new and more efficient approach for process and part qualification is becoming an urgent need in industry. The layerwise nature of additive manufacturing (AM) potentially allows anticipating qualification tasks in-line and in-process, aiming at reducing the time and costs devoted to post-process inspections, enabling at the same time an early detection of defects since their onset stage. Such opportunity is particularly attractive in the presence of highly complex shapes like lattice structures or metamaterials, which have been increasingly investigated for industrial adoption in various sectors, aiming to achieve enhanced mechanical properties and innovative functionalities. This paper presents a novel methodology to inspect the geometry of lattice structures while the part is being built. The method is specifically designed to tackle the natural variability affecting layerwise images gathered in laser powder bed fusion. To this aim, it combines the segmentation of in-situ powder bed images of solidified layers with a data modelling approach to synthesize the 3-D shape of each unit cell into a 1-D profile representation. Such low-dimensional representation is suitable to quickly detect undesired distortions that may have a detrimental impact on final quality and performance. By using post-process X-ray computed tomography as ground truth reference, this study shows the effectiveness of the proposed approach for in-line inspection, opening a novel and cost-efficient way to address complex shape qualification for lattice structures in AM.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104538"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663890","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}
Pub Date : 2024-09-05DOI: 10.1016/j.addma.2024.104543
Xinqi Wang , Xincin Cai , Jiwen Hu , Jiayi Li , Ruixiang Zhou , Shudong Lin
With the rapid development of 3D printing technology, it has penetrated various fields. In the context of global oil resource scarcity and increasing emphasis on environmental protection, developing high-performance bio-based 3D printing materials is a crucial means to overcome the limitations of petroleum resources and achieve sustainability. This paper proposed a "green" development method for high-performance, sunlight-curable vat photopolymerization 3D printing resins based on soybean oil and itaconic anhydride. Utilizing bio-based itaconic anhydride to replace traditional petroleum-based materials, a novel UV-curable prepolymer, IPESO, with 80.37 % high bio-carbon (Cbio) content and no volatile substances was synthesized. Simultaneously, a series of resins, IPESO-ETPTAx, with high mechanical and thermal properties were obtained utilizing ethoxylated trimethylolpropane triacrylate (ETPTA) as a diluent. Samples printed with IPESO-ETPTA40 achieve a high resolution of 40 µm on the xy-axis. This advanced material has broad application prospects in the field of vat photopolymerization 3D printing and provides a new strategy for the development of plant oil-based vat photopolymerization 3D printing resins.
随着 3D 打印技术的快速发展,它已渗透到各个领域。在全球石油资源紧缺、环境保护日益受到重视的背景下,开发高性能生物基3D打印材料是突破石油资源限制、实现可持续发展的重要手段。本文提出了一种基于大豆油和衣康酸酐的高性能阳光固化大桶光聚合3D打印树脂的 "绿色 "开发方法。利用生物基衣康酸酐替代传统的石油基材料,合成了一种新型紫外光固化预聚物 IPESO,其生物碳(Cbio)含量高达 80.37%,且不含挥发性物质。同时,利用乙氧基化三羟甲基丙烷三丙烯酸酯(ETPTA)作为稀释剂,获得了一系列具有高机械和热性能的 IPESO-ETPTAx 树脂。使用 IPESO-ETPTA40 印刷的样品在 x 轴上的分辨率高达 40 微米。这种先进的材料在大桶光聚合三维打印领域具有广阔的应用前景,并为植物油基大桶光聚合三维打印树脂的开发提供了一种新策略。
{"title":"Green synthesis of soybean oil-derived UV-curable resins for high-resolution 3D printing","authors":"Xinqi Wang , Xincin Cai , Jiwen Hu , Jiayi Li , Ruixiang Zhou , Shudong Lin","doi":"10.1016/j.addma.2024.104543","DOIUrl":"10.1016/j.addma.2024.104543","url":null,"abstract":"<div><div>With the rapid development of 3D printing technology, it has penetrated various fields. In the context of global oil resource scarcity and increasing emphasis on environmental protection, developing high-performance bio-based 3D printing materials is a crucial means to overcome the limitations of petroleum resources and achieve sustainability. This paper proposed a \"green\" development method for high-performance, sunlight-curable vat photopolymerization 3D printing resins based on soybean oil and itaconic anhydride. Utilizing bio-based itaconic anhydride to replace traditional petroleum-based materials, a novel UV-curable prepolymer, IPESO, with 80.37 % high bio-carbon (<em>C</em><sub>bio</sub>) content and no volatile substances was synthesized. Simultaneously, a series of resins, IPESO-ETPTAx, with high mechanical and thermal properties were obtained utilizing ethoxylated trimethylolpropane triacrylate (ETPTA) as a diluent. Samples printed with IPESO-ETPTA40 achieve a high resolution of 40 µm on the xy-axis. This advanced material has broad application prospects in the field of vat photopolymerization 3D printing and provides a new strategy for the development of plant oil-based vat photopolymerization 3D printing resins.</div></div>","PeriodicalId":7172,"journal":{"name":"Additive manufacturing","volume":"95 ","pages":"Article 104543"},"PeriodicalIF":10.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663892","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}