3D Printing and Additive Manufacturing最新文献

{"title":"Increasing Printable Solid Loading in Digital Light Processing Using a Bimodal Particle Size Distribution","authors":"Antoine P. Delarue, Ian M. McAninch, Amy M. Peterson, Christopher J. Hansen","doi":"10.1089/3dp.2022.0305","DOIUrl":"https://doi.org/10.1089/3dp.2022.0305","url":null,"abstract":"Digital light processing (DLP) is rapidly growing in popularity as an additive manufacturing method for the fabrication of composite structures, and is an effective way to prepare high-resolution filled parts, such as ceramic green parts or composite magnets. Yet, higher solid loadings of resins and the resulting dramatic increases in viscosity limit DLP printing for applications that depend upon maximization of filler content. In this work, we investigate the capacity of a bimodal particle size distribution to enable the printing of a photosensitive resin containing up to 70 vol% of fillers. Formulations with unimodal and bimodal solid loadings ranging from 50 to 72 vol% are prepared and their viscoelastic properties measured through rotational rheometry. The zero-shear viscosity of these formulations is fit with a Krieger-Dougherty model, and the dense random close packing fraction of particles determined from the fit is found to be 76.3 vol%. Parts with fine positive and negative features are printed to evaluate the resolution achievable with highly filled photosensitive resins. The part printed with a 70 vol% formulation shows negative features as small as 860 μm, and positive feature as small as 380 μm. Finally, parts with complex patterns are prepared with previously tested formulations, and thermogravimetric analysis results show that the filler content within the parts remains relatively constant over a 3-h print, with a decrease of 2 vol% of solids for the final printed layers.","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"95 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135146935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flexible Thermoplastic Polyurethane Composites with Ultraviolet Resistance for Fused Deposition Modeling 3D Printing","authors":"Andong Wang, Junhao Guo, Chenkang Shao, Caifeng Chen","doi":"10.1089/3dp.2023.0111","DOIUrl":"https://doi.org/10.1089/3dp.2023.0111","url":null,"abstract":"Currently, there is great demand for flexible three-dimensional (3D) printable thermoplastic polyurethane (TPU) wires with excellent ultraviolet (UV) resistance, which have broad application prospects in wearable products. In this study, UV-resistant TPU composites were obtained using a blending modification method. The relationship between the optimized parameters of fused deposition modeling 3D printing and mechanical properties of the TPU composite is discussed using an orthogonal test. This study observed that the UV absorption properties of TPU composites were enhanced, and the TiO2 and TiO2/ZnO fillers improved the tensile strength of TPU composites. After UV aging, the tensile strength and elongation of the TPU composite slightly decreased, but were still much higher than those of pure TPU. Among the printing parameters, printing speed had the greatest influence on the mechanical properties of TPU composites. When the printing speed was 80 mm/s, printing layer thickness was 0.25 mm, nozzle temperature was 220°C, and hot bed temperature was 50°C, the TPU composites exhibited the best elongation at break and tensile strength. After regression analysis, two regression models for the elongation at break and tensile strength of TPU composites were obtained and verified, which provide a reference for predicting the relationship between the printing parameters and mechanical properties of flexible TPU composites.","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135738607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D Printing of Noncytotoxic High-Resolution Microchannels in Bisphenol-A Ethoxylate Dimethacrylate Tissue-Mimicking Materials.","authors":"Roger Domingo-Roca, Lauren Gilmour, Oana Dobre, Stylianos Sarrigiannidis, Mairi E Sandison, Richard O'Leary, Joseph C Jackson-Camargo, Helen E Mulvana","doi":"10.1089/3dp.2021.0235","DOIUrl":"10.1089/3dp.2021.0235","url":null,"abstract":"<p><p>The ability to create cell-laden fluidic models that mimic the geometries and physical properties of vascularized tissue would be extremely beneficial to the study of disease etiologies and future therapies, including in the case of cancer where there is increasing interest in studying alterations to the microvasculature. Engineered systems can present significant advantages over animal studies, alleviating challenges associated with variable complexity and control. Three-dimensional (3D)-printable tissue-mimicking hydrogels can offer an alternative, where control of the biophysical properties of the materials can be achieved. Hydrogel-based systems that can recreate complex 3D structures and channels with diameters <500 μm are challenging to produce. We present a noncytotoxic photo-responsive hydrogel that supports 3D printing of complex 3D structures with microchannels down to 150 μm in diameter. Fine tuning of the 3D-printing process has allowed the production of complex structures, where for demonstration purposes we present a helical channel with diameters between 250 and 370 μm around a central channel of 150 μm in diameter in materials with mechanical and acoustic properties that closely replicate those of tissue. The ability to control and accurately reproduce the complex features of the microvasculature has value across a wide range of biomedical applications, especially when the materials involved accurately mimic the physical properties of tissue. An approach that is additionally cell compatible provides a unique setup that can be exploited to study aspects of biomedical research with an unprecedented level of accuracy.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 5","pages":"1101-1109"},"PeriodicalIF":2.3,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10599442/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54232280","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":"A Novel Approach of Customized Pelvic Implant Design Based on Symmetrical Analysis and 3D Printing.","authors":"Yuan Chai, Xiao-Bo Chen, Jesse A Estoque, Nick Birbilis, Qinghua Qin, Tomas Ward, Paul N Smith, Rachel W Li","doi":"10.1089/3dp.2021.0121","DOIUrl":"10.1089/3dp.2021.0121","url":null,"abstract":"<p><p>In pelvic trauma patients, the mismatch of complex geometries between the pelvis and fixation implant is a fundamental cause of unstable and displaced pelvic ring disruption, in which secondary intervention is strongly considered. The geometrical matching in the current customized implant design and clinical practice is through the nonfractured hemi-pelvis for the fractured pelvis. This design philosophy overlooks the anatomical difference between the hemipelves, and further, the geometrical asymmetry at local area still remains unknown. This study analyzed the anatomical asymmetry of a patient's 3D pelvic models from 13 patients. The hemipelves of each patient were registered by using an iterative closet algorithm to an optimum position with minimum deviations. The high deviation regions were summarized between the hemipelves in each case, and a color map was drawn on a hemipelvis model that identified the areas that had a high possibility to be symmetrically different. A severe pelvic trauma case was used to comprehend the approach by designing a 3D printed implant. Each fracture was then registered to the mirrored uninjured hemipelvis by using the same algorithm, and customized fixation implants were designed with reference to the fractured model. The customized fixation plates showed that the implants had lower geometrical deviation when attached onto the re-stitched fracture side than onto the mirrored nonfractured bone. These results indicate that the symmetrical analysis of bone anatomy and the deviation color map can assist with implant selection and customized implant design given the geometrical difference between symmetrical bones. The novel approach provides a scientific reference that improves the accuracy and overall standard of 3D printed implants.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"1 1","pages":"984-991"},"PeriodicalIF":2.3,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10599429/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41445485","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 the Spatial Arrangement of Floating Builds with Minimum Support on the Microstructural and Mechanical Characteristics of Electron Beam Additively Manufactured Biomedical Ti-6Al-4V Alloys.","authors":"Yi-Cheng Chen, Ping-Ho Chen, Meng-Hsiu Tsai, Shih-Fu Ou","doi":"10.1089/3dp.2021.0291","DOIUrl":"10.1089/3dp.2021.0291","url":null,"abstract":"<p><p>In this study, normal and floating builds of Ti-6Al-4V were fabricated by electron beam additive manufacturing. The effects of the spatial arrangement on the microstructure, mechanical properties, and surface roughness of the parts were investigated. Both the normal and floating builds exhibited an α+β lamellar microstructure, but the normal builds had finer grains compared to the floating builds. The microstructural characteristics were correlated with the thermal history, specifically the cooling rate, resulting from the connection plate (S45C for the normal builds and the powder bed for the floating builds). The compressive yield strength and hardness of the normal builds were higher than those of the floating builds, regardless of build location owing to the grain refinement effects on the normal builds. The top surface (TS) of the sample was smoothest, and the lateral surface of the sample was the roughest for both the normal and floating builds; however, the roughness of the TS and bottom surface samples did not differ significantly between normal and floating builds. There were no noticeable differences in the microstructure and mechanical properties of the builds in five different positions, that is, the center and four corners. Finally, these findings were used to develop a set of conceptual spatial arrangement designs, including floating builds, to optimize the microstructure and mechanical properties.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 5","pages":"1055-1063"},"PeriodicalIF":2.3,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10599422/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54232298","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":"Thermomechanical Properties of Polyjet Voxel-Printed Parts and the Effect of Percolation","authors":"Chengyeh Ho, Jiali Bao, Jing Xu","doi":"10.1089/3dp.2023.0126","DOIUrl":"https://doi.org/10.1089/3dp.2023.0126","url":null,"abstract":"The use of deformable materials in 3D printing has allowed for the fabrication of intricate soft robotics prototypes. Polyjet technology, with its ability to print multiple materials in a single print, has been popular in creating such designs. Vero and Agilus, the commercial materials provided by Polyjet, possess shape memory properties, making Polyjet ideal for high-precision and transformable applications. Voxel printing, where users assign materials to voxels, has allowed for the further expansion of design possibilities by tuning the properties of the jetted material. This study aims to investigate how different compositions of uniformly distributed Vero and Agilus voxels affect the thermomechanical properties of the voxel-printed part. In addition, high stiffness Vero droplets surrounded by a soft matrix of Agilus resemble polymer composites, thus calling for the examination of percolation, which is an important phenomenon in polymer composites. The study explores the presence of percolation in voxel-printed mixtures of Vero and Agilus and its impact on mechanical properties. Using dynamic thermomechanical analysis and thermomechanical analysis, the study characterizes the glass transition temperature (), maximum allowable strain, and modulus of the voxel-printed material at different compositions. The study found a highly linear relationship between and maximum yield strain with composition, and maximum yield strain occurs at 7°C above . On the other hand, there is a nonlinear relationship between the modulus and composition, which suggested that the percolation phenomenon might have altered the load distribution, therefore causing this inconsistency. So, in this study we used light microscopy, Monte Carlo simulations, and provided mathematical proofs to reveal the percolation threshold in voxel-printed parts, where Vero droplets suddenly form a single network that spreads across the material, altering the load distribution. This study is the first to highlight the percolation phenomenon in Polyjet voxel-printed parts and provides a useful guide for researchers in selecting suitable materials for their specific applications.","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134960217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Multiple Print-Head Displacement Mechanisms in 3D Space for Material Extrusion Machine","authors":"Ishant Singhal, Bobby Tyagi, Abhishek Raj, Akash Jain, Shashank Kapoor, Ankit Sahai, Rahul Swarup Sharma","doi":"10.1089/3dp.2023.0096","DOIUrl":"https://doi.org/10.1089/3dp.2023.0096","url":null,"abstract":"For wider adoption of the material extrusion (MatEx)-based additive manufacturing (AM) process, it is important to understand the systems for an improved production rate of the machine. This AM process is the most adaptable and popular due to its wide availability, scalability, compatibility with a broad range of thermoplastic materials, and decreasing cost of personal MatEx-based systems. The performance limits are being explored by many researchers, but none have tried to find the efficacy of different kinematic configurations. Kinematic configurations can significantly alter the efficiency of the machines. Most machines are operating on Cartesian positioning systems nowadays. Delta and polar positioning systems are not yet been extensively explored. In this study, Cartesian, delta, and polar systems of MatEx 3D printers are analyzed and compared based on physical inspection, print head dynamics and printed parts surface finish, dimensional accuracy, and build time. Based on the comparative study, the results show that the delta system-based 3D printer gives better surface finish and dimensional accuracy than polar and Cartesian system-based 3D printers. The analysis of build time with respect to the different infill densities and different printing speeds shows that the polar system-based 3D printers performed faster than the other two positing systems.","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134886896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluid Thermodynamic Simulation of Ti-6Al-4V Alloy in Laser Wire Deposition.","authors":"Xiang Wang, Lin-Jie Zhang, Jie Ning, Suck-Joo Na","doi":"10.1089/3dp.2021.0159","DOIUrl":"10.1089/3dp.2021.0159","url":null,"abstract":"<p><p>A 3D numerical model of heat transfer and fluid flow of molten pool in the process of laser wire deposition was presented by computational fluid dynamics technique. The simulation results of the deposition morphology were also compared with the experimental results under the condition of liquid bridge transfer mode. Moreover, they showed a good agreement. Considering the effect of recoil pressure, the morphology of the deposit metal obtained by the simulation was similar to the experiment result. Molten metal at the wire tip was peeled off and flowed into the molten pool, and then spread to both sides of the deposition layer under the recoil pressure. In addition, the results of simulation and high-speed charge-coupled device presented that a wedge transition zone, with a length of ∼6 mm, was formed behind the keyhole in the liquid bridge transfer process, where the height of deposited metal decreased gradually. After solidification, metal in the transition zone retained the original melt morphology, resulting in a decrease in the height of the tail of the deposition layer.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 4","pages":"661-673"},"PeriodicalIF":2.3,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10440678/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10052243","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":"Selective Laser Melting of TiC-Fe via Laser Pulse Shaping: Microstructure and Mechanical Properties.","authors":"Himanshu Singh Maurya, Lauri Kollo, Marek Tarraste, Kristjan Juhani, Fjodor Sergejev, Konda Gokuldoss Prashanth","doi":"10.1089/3dp.2021.0221","DOIUrl":"10.1089/3dp.2021.0221","url":null,"abstract":"<p><p>In the present study, TiC-Fe cermets were fabricated through selective laser melting (SLM) for the first time employing pulse wave using a pulse shaping technique and regular laser pulse wave. Two samples were fabricated each with adapting pulse shaping technique and regular laser pulse wave with varied laser peak power and exposure time to obtain an optimized parameter. The pulse shaping technique proves to be an optimal method for fabrication of the TiC-Fe-based cermet. The effect of the laser peak power and pulse shaping on the microstructure development was investigated through scanning electron microscopy and X-ray diffraction analysis. Two-phased microstructures revealed the distribution of TiC and Fe. A maximum hardness and fracture toughness of 1010 ± 65 MPa and 16.3 ± 1.7 MPa m^1/2, respectively, were observed for the pulsed-shaped samples illustrating that pulse shaping can be an effective way to avoid cracking in brittle materials processed by SLM.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 4","pages":"640-649"},"PeriodicalIF":2.3,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10440667/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10059365","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":"Generative Design of Structured Materials for Controlled Frequency Responses.","authors":"Wuxin Yang, Loulin Huang, Sarat Singamneni","doi":"10.1089/3dp.2021.0241","DOIUrl":"10.1089/3dp.2021.0241","url":null,"abstract":"<p><p>Spatially varying material properties allow the dynamic response of structural systems to be almost arbitrarily tailored, far beyond the first or fundamental natural frequency. Continuing advances in manufacturing technology are making it possible to achieve the necessary range of stiffness and density variations, but the design of these property distributions is a challenging task because of the complex multidimensional nature of the problem. Generative design methods based on evolutionary optimization algorithms have been successfully used to obtain solutions based on multi-material distributions. However, the applicability of these solutions is limited by their reliance on multi-material additive manufacturing (AM), which currently only offers digitally mixed acrylic polymer options that are generally unsuitable to produce functional parts. A novel structured material solution is proposed here, in which the problem domain is divided into several volume elements (voxels), each of which contains a structure whose geometrical form is altered to adjust its effective properties to desired values. The single material structural solution will be amenable for ready fabrication by the powder-based selective laser sintering and melting processes with real engineering polymer and metal systems, thereby allowing for the realization of the benefits in real-world applications. The resulting continuous design spaces are searched using a modern evolutionary algorithm, the covariance matrix adaptation evolution strategy (CMA-ES). A MATLAB implementation of this evolutionary design method, in conjunction with finite element simulations for fitness evaluation, showed good convergence for several different cantilever beam test cases when tested against several different sets of target natural frequencies. Correlations with the multi-material solutions show that the single structured material approach is on par or even better in some cases, even though the test domain was discretized into 80% fewer voxels than for the multi-material case. Furthermore, the voxel structures can be realized using current AM technologies.</p>","PeriodicalId":54341,"journal":{"name":"3D Printing and Additive Manufacturing","volume":"10 4","pages":"792-807"},"PeriodicalIF":2.3,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10440660/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10114895","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}