3D Printing and Additive Manufacturing最新文献

{"title":"Advances in Online Detection Technology for Laser Additive Manufacturing: A Review.","authors":"Rui Li Zu, Dong Liang Wu, Jiang Fan Zhou, Zhan Wei Liu, Hui Min Xie, Sheng Liu","doi":"10.1089/3dp.2021.0049","DOIUrl":"10.1089/3dp.2021.0049","url":null,"abstract":"<p><p>In additive manufacturing (AM), the mechanical properties of manufactured parts are often insufficient due to complex defects and residual stresses, limiting their use in high-value or mission-critical applications. Therefore, the research and application of nondestructive testing (NDT) technologies to identify defects in AM are becoming increasingly urgent. This article reviews the recent progress in online detection technologies in AM, a special introduction to the high-speed synchrotron X-ray technology for real-time <i>in situ</i> observation, and analysis of defect formation processes in the past 5 years, and also discusses the latest research efforts involving process monitoring and feedback control algorithms. The formation mechanism of different defects and the influence of process parameters on defect formation, important parameters such as defect spatial resolution, detection speed, and scope of application of common NDT methods, and the defect types, advantages, and disadvantages associated with current online detection methods for monitoring three-dimensional printing processes are summarized. In response to the development requirements of AM technology, the most promising trends in online detection are also prospected. This review aims to serve as a reference and guidance for the work to identify/select the most suitable measurement methods and corresponding control strategy for online detection.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"467-489"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280211/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10087898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automated Defect Recognition for Additive Manufactured Parts Using Machine Perception and Visual Saliency.","authors":"Jan Petrich, Edward W Reutzel","doi":"10.1089/3dp.2021.0224","DOIUrl":"10.1089/3dp.2021.0224","url":null,"abstract":"<p><p>Metal additive manufacturing (AM) is known to produce internal defects that can impact performance. As the technology becomes more mainstream, there is a growing need to establish nondestructive inspection technologies that can assess and quantify build quality with high confidence. This article presents a complete, three-dimensional (3D) solution for automated defect recognition in AM parts using X-ray computed tomography (CT) scans. The algorithm uses a machine perception framework to automatically separate visually salient regions, that is, anomalous voxels, from the CT background. Compared with supervised approaches, the proposed concept relies solely on visual cues in 3D similar to those used by human operators in two-dimensional (2D) assuming no <i>a priori</i> information about defect appearance, size, and/or shape. To ingest any arbitrary part geometry, a binary mask is generated using statistical measures that separate lighter, material voxels from darker, background voxels. Therefore, no additional part or scan information, such as CAD files, STL models, or laser scan vector data, is needed. Visual saliency is established using multiscale, symmetric, and separable 3D convolution kernels. Separability of the convolution kernels is paramount when processing CT scans with potentially billions of voxels because it allows for parallel processing and thus faster execution of the convolution operation in single dimensions. Based on the CT scan resolution, kernel sizes may be adjusted to identify defects of different sizes. All adjacent anomalous voxels are subsequently merged to form defect clusters, which in turn reveals additional information regarding defect size, morphology, and orientation to the user, information that may be linked to mechanical properties, such as fatigue response. The algorithm was implemented in MATLAB™ using hardware acceleration, that is, graphics processing unit support, and tested on CT scans of AM components available at the Center for Innovative Materials Processing through Direct Digital Deposition (CIMP-3D) at Penn State's Applied Research Laboratory. Initial results show adequate processing times of just a few minutes and very low false-positive rates, especially when addressing highly salient and larger defects. All developed analytic tools can be simplified to accommodate 2D images.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"406-419"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280214/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9710256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Closed-Loop Filament Feed Control in Fused Filament Fabrication.","authors":"Michele Moretti, Arianna Rossi","doi":"10.1089/3dp.2021.0236","DOIUrl":"10.1089/3dp.2021.0236","url":null,"abstract":"<p><p>Fused filament fabrication (FFF) is an additive manufacturing process where a thermoplastic polymeric material, provided in the form of a filament, is extruded to create layers. Achieving a consistent flow of the extruded material is key to ensure quality of the final part. Extrudate flow depends on many factors; among these, the rate at which the filament is fed into the extruder. In a conventional FFF machine, filament transport is achieved through the use of a drive gear. However, slippage between the gear and the filament may occur, leading to reduced transport and the consequent local decrease of extrudate flow rate, which in turn leads to a series of imperfections in the fabricated part due to underextrusion, including reduced density. In this work, we propose a closed-loop control system to ensure the correct filament transport to the extruder. The system works through the comparison between the nominal transport of the filament and the actual filament transport measured using an encoder. The measured value is used to correct the filament feed rate in real time, ensuring a material flow close to the nominal one, regardless of the other process parameters. In this work, an instrumented FFF machine prototype was used to investigate the performance of the approach. For validation, parts were realized using different process parameters, while enabling and disabling the closed-loop control system. Results showed that the relative filament transport error decreased from up to 9% to below 0.25% and a density increase up to ∼10% regardless of the process parameters, as well as the reduction of interlayer and intralayer voids, as highlighted through cross-sectional imaging of realized samples. A reduction of defects on realized parts was observed, especially at higher fabrication feed rates.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"500-513"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280219/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10068946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast and Accurate Defects Detection for Additive Manufactured Parts by Multispectrum and Machine Learning.","authors":"Lingbao Kong, Xing Peng, Yao Chen","doi":"10.1089/3dp.2021.0191","DOIUrl":"10.1089/3dp.2021.0191","url":null,"abstract":"<p><p>Traditional defect detection methods for metal additive manufacturing (AM) have the problems of low detection efficiency and accuracy, while the existing machine learning detection algorithms are of poor adaptability and complex structure. To address the above problems, this article proposed an improved You Only Look Once version 3 (YOLOv3) algorithm to detect the surface defects of metal AM based on multispectrum. The weighted <i>k</i>-means algorithm is used to cluster the target samples to improve the matching degree between the prior frame and the feature layer. The network structure of YOLOv3 is modified by using the lightweight MobileNetv3 to replace the Darknet-53 in the original YOLOv3 algorithm. Dilated convolution and Inceptionv3 are added to improve the detection capability for surface defects. A multispectrum measuring system was also developed to obtain the AM surface data with defects for experimental verification. The results show that the detection accuracy in the test set by YOLOv3-MobileNetv3 network is 11% higher than that by the original YOLOv3 network on average. The detection accuracy for cracking defects of the three types of defects is significantly increased by 23.8%, and the detection speed is also increased by 18.2%. The experimental results show that the improved YOLOv3 algorithm realizes the end-to-end surface defect detection for metal AM with high accuracy and fast speed, which can be further applied for online defect detection.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"393-405"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280201/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10087900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Microstructure and Dislocation Density on Material Removal and Surface Finish of Laser Powder Bed Fusion 316L Stainless Steel Subject to a Self-Terminating Etching Process.","authors":"Stephanie Prochaska, Michael Walker, Owen Hildreth","doi":"10.1089/3dp.2022.0190","DOIUrl":"10.1089/3dp.2022.0190","url":null,"abstract":"<p><p>Postprocessing of additively manufactured (AM) metal parts to remove support structures or improve the surface condition can be a manually intensive process. One novel solution is a two-step, self-terminating etching process (STEP), which achieves both support removal and surface smoothing. While the STEP has been demonstrated for laser powder bed fusion (L-PBF) 316L stainless steel, this work evaluates the impact of pre-STEP heat treatments and resulting changes in dislocation density and microstructure on the resulting surface roughness and amount of material removed. Two pre-STEP heat treatments were evaluated: stress relief at 470°C for 5 h and recrystallization-solution annealing at 1060°C for 1 h. Additionally, one set of specimens was processed without the pre-STEP heat treatment (as-printed condition). Dislocation density and phase composition were quantified using X-ray diffraction along with standard, metallurgical stain-etching techniques. This work, for the first time, highlights the mechanisms of sensitization of AM L-PBF 316L stainless steel and provides fundamental insights into selective etching of these materials. Results showed that the sensitization depth decreased with increasing dislocation density. For samples etched at a STEP bias of 540 mV_SHE, material removal terminated at grain boundaries; therefore, the fine-grained stress-relieved specimen had the lowest post-STEP surface roughness. For surface roughness optimization, parts should be stress relived pre-STEP. However, to achieve more material removal, pre-STEP solution annealing should be performed.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"373-382"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280176/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10087892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance Analysis of Conventional and DMLS Copper Electrode During EDM Process in AA4032-TiC Composite.","authors":"Senthilkumar Thangarajan Sivasankaran, Senthil Kumar Shanmugakani, Rathinavel Subbiah","doi":"10.1089/3dp.2021.0030","DOIUrl":"10.1089/3dp.2021.0030","url":null,"abstract":"<p><p>In recent days, the additive manufacturing process plays a vital role in the production of tool electrodes, which are used in the electrical discharge machining (EDM) process. In this work, the copper (Cu) electrodes prepared using the direct metal laser sintering (DMLS) process are used for the EDM process. The performance of the DMLS Cu electrode is studied by machining the AA4032-TiC composite material using the EDM process. Then the performance of the DMLS Cu electrode is compared with the conventional Cu electrode. Three input parameters, such as peak current (A), pulse on time (s), and gap voltage (v), are selected for the EDM process. The performance measures, which are determined during the EDM process, are material removal rate (MRR), tool wear rate, surface roughness (SR), microstructural analysis of machined surface, and residual stress. At a higher pulse on time, more material was removed from the workpiece surface and thus MRR is enhanced. Likewise, at a higher peak current, the SR is amplified and thus wider craters are formed on the machined surface. The residual stress on the machined surface has influenced the formation of craters, microvoids, and globules. Lower SR and residual stress are attained by using DMLS Cu electrode, whereas MRR is higher when using conventional Cu electrode.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"569-583"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280191/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9717163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of High Laser Energy Density on Selective Laser Melted 316L Stainless Steel: Analysis on Metallurgical and Mechanical Properties and Comparison with Wrought 316L Stainless Steel.","authors":"Pradeep Kumar Shanmuganathan, Dinesh Babu Purushothaman, Marimuthu Ponnusamy","doi":"10.1089/3dp.2021.0061","DOIUrl":"10.1089/3dp.2021.0061","url":null,"abstract":"<p><p>The austenitic 316L stainless steel (SS) is used extensively for marine applications as well as in construction, processing, and petrochemical industries due to its outstanding corrosion resistance properties. This study investigates the density, microhardness, and microstructural development of 316L SS samples fabricated by selective laser melting (SLM) under high laser energy densities. The selective laser melted (SLMed) specimens were fabricated under high laser energy densities (500, 400, and 333.33 J/mm³) and their metallurgical and mechanical properties were compared with the wrought specimen. SLMed 316L SS showed excellent printability, thereby enabling the fabrication of parts near full density. The porosity content present in the SLMed specimens was determined by both the image analysis method and Archimedes method. SLMed 316L specimens fabricated by the SLM process allowed observation of a microhardness of 253 HV_1.0 and achieved relative density up to 98.022%. Microstructural analysis using optical microscopy and phase composition analysis by X-ray diffraction (XRD) has been performed. Residual stresses were observed using the XRD method, and compressive stress (-68.9 MPa) was noticed in the as-printed specimen along the surface of the build direction. The microstructure of the as-built SLMed specimens consisted of a single-phase face-centered cubic solid solution with fine cellular and columnar grains along the build direction. The SLMed specimens seemed to yield better results than the wrought counterpart. IRB approval and Clinical Trial Registration Number are not applicable for this current work.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"383-392"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280227/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9765153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of <i>In Situ</i> Vibration During Wire and Arc Additive Manufacturing.","authors":"Chi Ma, Changlong Li, Yuhao Yan, Yonghong Liu, Xinlei Wu, Dege Li, Hui Jin, Fan Zhang","doi":"10.1089/3dp.2021.0053","DOIUrl":"10.1089/3dp.2021.0053","url":null,"abstract":"<p><p>Wire and arc additive manufacturing (WAAM) is becoming a promising technique due to its high deposition rate and low cost. However, WAAM faces challenges of coarse grains. In this study, a novel <i>in situ</i> vibration method was proposed to suppress these imperfections of WAAM. Temperature and vibration distributions were explored first, and the optimized parameters were utilized for manufacturing low-carbon steel parts. The results revealed that after the vibration, the average grain size in fine grain zone was reduced from 9.8 to 7.1 μm, and that in coarse grain zone was declined from 10.6 to 7.4 μm, respectively. No large deformation occurred due to the low temperature. Grain refining was attributed to more dendrite fragments induced by excessive stress at the roots of dendrites. The refined grains enhanced mechanical strength of the parts in both X and Z directions and improved the average hardness. After the vibration, the ultimate tensile strength and yield strength were increased to 522.5 and 395 MPa, which represented an increase of 10% and 13.8%, respectively. The average hardness was improved to 163 HV, which was an increase of 10.1%.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"524-535"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280222/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10068947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Ag@Cu Water-Based Nanomaterial Conductive Ink in 3D Printing.","authors":"Chenfei Zhao, Jun Wang, Zhuoqing Zhang, Bo Qian","doi":"10.1089/3dp.2021.0199","DOIUrl":"10.1089/3dp.2021.0199","url":null,"abstract":"<p><p>Copper (Cu) nanoparticles are considered a promising alternative to silver (Ag) and gold (Au) for printed electronics applications. Because Cu has higher electrical conductivity, it is significantly cheaper than Ag and Au. To study the applicability of electronic printing, we prepared Ag@Cu conductive ink by using a stepwise feeding method to disperse nano Ag and nano Cu in ethanol and water. The ink has the advantages of nontoxic, low content, and low cost. A three-dimensional (3D) model was designed, and a conductive pattern was printed on the photo paper substrate using extrusion 3D printing technology. The influence of waterborne resin on the adhesion of conductive patterns is discussed. The printed conductive pattern can maintain the stability of conductivity after 100 bending cycles. The conductive pattern has good thermal stability. It can be tested 10 times under 2 conditions of 85°C and room temperature to maintain good conductivity. This shows that Ag@Cu conductive ink printed flexible electronic products are competitive.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"552-558"},"PeriodicalIF":3.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280186/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10068942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bulk-Material Bond Strength Exists in Extrusion Additive Manufacturing for a Wide Range of Temperatures, Speeds, and Layer Times.","authors":"Amirpasha Moetazedian, James Allum, Andrew Gleadall, Vadim V Silberschmidt","doi":"10.1089/3dp.2021.0112","DOIUrl":"10.1089/3dp.2021.0112","url":null,"abstract":"<p><p>Do extrusion temperature, printing speed, and layer time affect mechanical performance of interlayer bonds in material extrusion additive manufacturing (MEAM)? The question is one of the main challenges in 3D printing of polymers. This article aims to analyze the independent effect of printing parameters on interlayer bonding in MEAM. In previous research, printing parameters were unavoidably interrelated, such as printing speed and layer cooling time. Here, original specimen designs allow the effects to be studied independently for the first time to provide new understanding of the effects of a wide range of thermal factors on mechanical properties of 3D-printed polylactide. The experimental approach used direct GCode design to manufacture specially designed single-filament-thick specimens for tensile testing to measure mechanical and thermal properties normal to the interface between layers. In total, five different extrusion temperatures (a range of 60°C), five different printing speeds (a 16-fold change in the magnitude) and four different layer times (an 8-fold change) were independently studied. The results demonstrate interlayer bond strength to be equivalent to that of the bulk material within experimental scatter. This study provides strong evidence about the crucial role of microscale geometry for apparent interlayer bond strength relative to the role of thermal factors. By designing specimens specifically for the MEAM process, this study clearly demonstrates that bulk-material strength can be achieved for interlayer bonds in MEAM even when printing parameters change severalfold. Widespread industrial and academic efforts to improve interlayer bonding should be refocused to study extrusion geometry-the primary cause of anisotropy in MEAM.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 3","pages":"514-523"},"PeriodicalIF":2.3,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10280202/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10068943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}