Artículos de revistas: "Two component injection molding"

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Chen, Jyun Yi y Wen Bin Young. "Two-Component Injection Molding of Molded Interconnect Devices". Advanced Materials Research 628 (diciembre de 2012): 78–82. http://dx.doi.org/10.4028/www.scientific.net/amr.628.78.

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Molded Interconnect Device (MID) can be defined as that an injection-molded plastic part combining with electrical and mechanical functions in a single device. This study is to examine the application of micro injection molding technology to the two-component molding process for the MID fabrication. The process involves the first shot of a plastic component with channel patterns on the surface. A second shot by micro injection molding technology is applied to fill the channel with the plateable plastics. The effects of the micro injection molding process parameters on filled line width of the two-component MID will be investigated. It is concluded that, for a MID component, the molding conditions must be designed carefully to keep the thickness variation below the allowable value. It is also found from the experiments that the thickness interference may in the range from 92 m to 196 m to have adequate molding at the second shot.

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Keestra, B. J., P. D. Anderson y H. E. H. Meijer. "Two Component Injection Molding of Phase Separating Blends". International Polymer Processing 21, n.º 2 (mayo de 2006): 168–74. http://dx.doi.org/10.3139/217.1907.

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Bräuer, M., B. Hupfer, J. Nagel y D. Lehmann. "Chemical modification of polyurethane for two-component injection molding". Polymer Engineering & Science 42, n.º 4 (abril de 2002): 859–69. http://dx.doi.org/10.1002/pen.10997.

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Yang, Lung Jieh, Chung Yu Kao y Chin Kwang Huang. "Development of Flapping Ornithopters by Precision Injection Molding". Applied Mechanics and Materials 163 (abril de 2012): 125–32. http://dx.doi.org/10.4028/www.scientific.net/amm.163.125.

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The authors investigate the component fabrication of a flapping ornithopter with 21.6 cm wing span by using precision injection molding. For making a bio-mimicking flapper like birds, two fold of plastic injection moldings have been done. Firstly the flapping mechanism of a 4-bar linkage gear transmission module has been studied, and the according plastic components for the gear transmission module were designed as light as possible. Thereafter the injection flow analysis in the multi-mold cavity and the fabrication parameters of the molding process has been implemented. The finished polyoxymethylene (POM) components for the transmission module of 1.2 gram in mass finally verify the design and process of the precision injection molding. After the ornithopterGolden Snitchwas assembled and tested with the fore-mentioned plastic 4-bar linkage, a maximum flight record of 480 sec was created in 2010. The second framework of injection molding is to design a bird-like expandable polystyrene (EPS) fuselage with 19.5 cm in length as the mechanical protection. After this ornithopterGolden Snitch-Prowas assembled, it has a successful flight of 230 sec and 100 times of landing capability. In summary, the fabrication of a polymeric bird-like flapper is proved, and the precision injection molding technique shows its feasibility in realization of ornithopters.

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Antusch, Steffen, Lorelei Commin, Marcus Mueller, Volker Piotter y Tobias Weingaertner. "Two component tungsten powder injection molding – An effective mass production process". Journal of Nuclear Materials 447, n.º 1-3 (abril de 2014): 314–17. http://dx.doi.org/10.1016/j.jnucmat.2013.11.007.

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Ruh, Andreas, Volker Piotter, Klaus Plewa, Hans-Joachim Ritzhaupt-Kleissl y Juergen Hausselt. "Development of Two-Component Micropowder Injection Molding (2C-MicroPIM)-Process Development". International Journal of Applied Ceramic Technology 8, n.º 3 (mayo de 2011): 610–16. http://dx.doi.org/10.1111/j.1744-7402.2009.02468.x.

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7

Egész, Ádám y László A. Gömze. "Quality Control Methods of Al₂O₃ Based Ceramic Injection Molding Raw Materials". Materials Science Forum 812 (febrero de 2015): 35–40. http://dx.doi.org/10.4028/www.scientific.net/msf.812.35.

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In the illuminant industry, for producing arc tube parts for high intensity discharge lamps the applied method is the ceramic injection molding. The ceramic arc tube parts are made of high purity alumina powder. By producing ceramic parts, one of the most critical step is to optimizing the injection molding process, [1] but first of all we need to know the properties of injection molding raw material, because later the molding process will be optimized for this material, to decrease the amount of cracked ceramics.For producing ceramic arc tube parts (plugs), there are used two different major components for producing injection molding raw material (feedstock): high purity alumina powder as the main component, and an organic paraffin wax as a binder material. It is expressly important to know the material, physical and chemical properties of these components, since mainly these have affect on the homogenity of feedstock, and therefore on the quality of end product. [3]In this research, both of the main components and the moldable raw material was investigated by visual, physical, chemical and thermal methods. As most important and main statement, the researchers found that the dynamic viscosity of the injection molding raw material depends on the used mixer equipment and the applied deformation velocity.Applied analitycal methods were laser granulometry, differential thermal analysis, and rheological analysis.

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Goharian, Amirhossein, Ahmad Ramli Rashidi, Mohammed Rafiq Abdul Kadir, R. A. Abdullah y Mat Uzir Wahit. "Development of Novel Polymer Composite Beam Using Ultrasonic Welding Process for Acetabular Cup Prosthesis". Key Engineering Materials 471-472 (febrero de 2011): 945–50. http://dx.doi.org/10.4028/www.scientific.net/kem.471-472.945.

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The objective of this study was to prepare a basic contributed model in beam to examine this novel composition supposed to apply for acetabular cup. Injection molding process used to manufacture of the component whereas ultrasonic welding was utilized to joint two components. Molding and welding value parameters were carried out by trial and error process. Strength bonding of two components was evaluated by single cantilever beam (SCB) test. The Interfacial fracture energy attained by single cantilever beam (SCB) test was exceeded over 1800 after 70 mm crack propagation.

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9

Ruh, Andreas, Adam-Mwanga Dieckmann, Richard Heldele, Volker Piotter, Robert Ruprecht, Christian Munzinger, Jürgen Fleischer y Jürgen Haußelt. "Production of two-material micro-assemblies by two-component powder injection molding and sinter-joining". Microsystem Technologies 14, n.º 12 (4 de junio de 2008): 1805–11. http://dx.doi.org/10.1007/s00542-008-0646-8.

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10

Holstein, N., V. Piotter, J. Lorenz, E. Oskotski, R. Ruprecht, G. Schanz y J. Hausselt. "Electroforming of Metallic Microparts on Sacrificial Molds made by Two-component Injection Molding". Advanced Engineering Materials 6, n.º 8 (agosto de 2004): 643–53. http://dx.doi.org/10.1002/adem.200400028.

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11

Ruh, Andreas, Thomas Hanemann, Richard Heldele, Volker Piotter, Hans-Joachim Ritzhaupt-Kleissl, Juergen Hausselt, Thomas Hanemann, Richard Heldele y Juergen Hausselt. "Development of Two-Component Micropowder Injection Molding (2C MicroPIM): Characteristics of Applicable Materials". International Journal of Applied Ceramic Technology 8, n.º 1 (15 de agosto de 2009): 194–202. http://dx.doi.org/10.1111/j.1744-7402.2009.02427.x.

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12

Xie, Zhi Peng, Lin Lin Wang, Xian Feng Yang y Zhen Ting Zhang. "Water Debinding for Zirconia Powder Injection Molding". Key Engineering Materials 368-372 (febrero de 2008): 732–35. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.732.

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Water debinding is an important debinding technique for ceramic injection molding. However cracks or blisters usually generate during water extraction. In this paper, two types of multi-component binder systems were studied: (1) a major fraction of polyethylene glycol (PEG), and a minor fraction of polyvinyl butyra (PVB) and other additives. (2) a major fraction of PEG, and a minor fraction of polymethyl methacrylate (PMMA) and other additives. Mechanism of defects generation was investigated, and PEGs with various molecular weights were introduced to avoid cracks or blisters during the process. Further more, the compatibilities of PEG/PVB and PEG/PMMA were studied. The results showed that PEG and PMMA exhibited better compatibility, with the feedstock more homogeneous and sintered ceramic parts higher strength.

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Loaldi, Dario, Francesco Regi, Federico Baruffi, Matteo Calaon, Danilo Quagliotti, Yang Zhang y Guido Tosello. "Experimental Validation of Injection Molding Simulations of 3D Microparts and Microstructured Components Using Virtual Design of Experiments and Multi-Scale Modeling". Micromachines 11, n.º 6 (24 de junio de 2020): 614. http://dx.doi.org/10.3390/mi11060614.

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The increasing demand for micro-injection molding process technology and the corresponding micro-molded products have materialized in the need for models and simulation capabilities for the establishment of a digital twin of the manufacturing process. The opportunities enabled by the correct process simulation include the possibility of forecasting the part quality and finding optimal process conditions for a given product. The present work displays further use of micro-injection molding process simulation for the prediction of feature dimensions and its optimization and microfeature replication behavior due to geometrical boundary effects. The current work focused on the micro-injection molding of three-dimensional microparts and of single components featuring microstructures. First, two virtual a studies were performed to predict the outer diameter of a micro-ring within an accuracy of 10 µm and the flash formation on a micro-component with mass a 0.1 mg. In the second part of the study, the influence of microstructure orientation on the filling time of a microcavity design section was investigated for a component featuring micro grooves with a 15 µm nominal height. Multiscale meshing was employed to model the replication of microfeatures in a range of 17–346 µm in a Fresnel lens product, allowing the prediction of the replication behavior of a microfeature at 91% accuracy. The simulations were performed using 3D modeling and generalized Navier–Stokes equations using a single multi-scale simulation approach. The current work shows the current potential and limitations in the use of micro-injection molding process simulations for the optimization of micro 3D-part and microstructured components.

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14

Carvalho, Marcio A., Paulo A. P. Wendhausen y T. Hartwig. "Production of Composite Parts of H13 and 316L by Two Components Injection Molding". Materials Science Forum 530-531 (noviembre de 2006): 236–41. http://dx.doi.org/10.4028/www.scientific.net/msf.530-531.236.

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A new development in MIM aims at the manufacturing of parts out of two materials, the Two Components Injection Molding, which allows the production of parts with different materials in distinct locations, obtaining different properties in distinct regions of the part. In this work an austenitic stainless steel was combined with tool steel, based on the Two Components Injection Molding process, using dilatometric experiments to analyze the behaviour of materials during sintering. Metallographic analyses and tensile tests were made to verify the microstructure and the strength in the contact area of the two materials.

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15

Schroeder, Renan, Antônio I. Ramos Filho, Cristiano Binder y Aloisio N. Klein. "Powder Injection Molding of Multimaterial Parts - Self Lubricating Steel Combined with Plain-Carbon Steel". Materials Science Forum 727-728 (agosto de 2012): 243–47. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.243.

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Powder Injection Molding allows processing of multifunctional parts through combination of different materials in a single structure. This technique so-called Two Components Powder Injection Molding has been developed some years ago and now is rapidly being considered for many engineering applications. In this paper, some important aspects of materials selection and processing conditions are reviewed in order to look insight of the technology. To show how successful can be the technique, carbonyl iron feedstock was co-sintered to the recently developed self-lubricating steel, aiming at different tribological properties in each side of the final component. Defect-free parts were obtained and the tensile resistance was in the same range of single material parts, representing a very strong bonding interface.

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16

Piotter, Volker, G. Finnah, B. Zeep, Robert Ruprecht y Jürgen Haußelt. "Metal and Ceramic Micro Components Made by Powder Injection Molding". Materials Science Forum 534-536 (enero de 2007): 373–76. http://dx.doi.org/10.4028/www.scientific.net/msf.534-536.373.

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To overcome the lack of micro manufacturing processes suitable for medium and large scale production as well as to process high resistive materials a special variant of micro injection molding is currently under development: micro powder injection molding (MicroPIM), which already enables the manufacturing of finest detailed components with structure sizes down to a few ten micrometer. In order to expand the scope of application of MicroPIM, tests are being conducted with pure tungsten powders or tungsten alloy powders. As further improvement, micro twocomponent injection molding allows, for example, the fabrication of micro components consisting of two ceramic materials with different physical properties.

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17

Antusch, Steffen, Marcus MÜller, Prachai Norajitra, Gerald Pintsuk, Volker Piotter, Hans-Joachim Ritzhaupt-Kleissl y Tobias WeingÄrtner. "Two-Component Tungsten Powder Injection Molding for Mass Production of He-Cooled DEMO Divertor Parts". Fusion Science and Technology 62, n.º 1 (agosto de 2012): 110–15. http://dx.doi.org/10.13182/fst12-a14121.

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18

Mulser, Marco, Georg Veltl y Frank Petzoldt. "Development of magnetic/non-magnetic stainless steel parts produced by two-component metal injection molding". International Journal of Precision Engineering and Manufacturing 17, n.º 3 (marzo de 2016): 347–53. http://dx.doi.org/10.1007/s12541-016-0043-7.

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19

Li, Tao, Qingfa Li, J. Y. H. Fuh, Poh Ching Yu y L. Lu. "Two-material powder injection molding of functionally graded WC–Co components". International Journal of Refractory Metals and Hard Materials 27, n.º 1 (enero de 2009): 95–100. http://dx.doi.org/10.1016/j.ijrmhm.2008.04.005.

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20

Liu, Lin, X. L. Ni, Hai Qing Yin y Xuan Hui Qu. "Study on Binder System for Micro Powder Injection Molding of ZrO₂ Ceramic". Materials Science Forum 706-709 (enero de 2012): 1948–54. http://dx.doi.org/10.4028/www.scientific.net/msf.706-709.1948.

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Micro powder injection molding has been accepted as a potential forming technology for large-scale production of miniature components in industries. However, mold filling capability is often poor due to the blind hole structure of the die cavity, which restricts the widespread application of this technique. In this paper, ZrO2 micro gears with addendum circle ranging from 900μm to 200μm were studied. Instead of using traditional PW-HDPE-SA binder as in powder injection molding, thermoplastic binder system is optimized here for better replication of micro gear. It is found that the dimensional accuracy and demold after injection molding can be improved by utilizing proper binder system. ZrO2 feedstock with a powder loading of 46vol.% and the binder system consisting of BW, HDPE and SA was successfully injection molded and demolded, which indicates good mold filling capability and sufficient demolding strength. The binder system was successfully removed by debinding process in two steps, solvent debinding followed by thermal debinding. Debound components free of defects were obtained. Keywords: Micro powder injection molding, ZrO2 feedstock, Binder system, Molding filling capability, Demolding strength

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21

Loaldi, Dario, Danilo Quagliotti, Matteo Calaon, Paolo Parenti, Massimiliano Annoni y Guido Tosello. "Manufacturing Signatures of Injection Molding and Injection Compression Molding for Micro-Structured Polymer Fresnel Lens Production". Micromachines 9, n.º 12 (10 de diciembre de 2018): 653. http://dx.doi.org/10.3390/mi9120653.

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Injection compression molding (ICM) provides enhanced optical performances of molded polymer optics in terms of birefringence and transmission of light compared to Injection molding (IM). Nevertheless, ICM requires case-dedicated process optimization to ensure that the required high accuracy geometrical replication is achieved, particularly especially in the case of surface micro-features. In this study, two factorial designs of experiments (DOE) were carried out to investigate the replication capability of IM and ICM on a micro structured Fresnel lens. A laser scanning confocal microscope was employed for the quality control of the optical components. Thus, a detailed uncertainty budget was established for the dimensional measurements of the replicated Fresnel lenses, considering specifically peak-to-valley (PV) step height and the pitch of the grooves. Additional monitoring of injection pressure allowed for the definition of a manufacturing signature, namely, the process fingerprint for the evaluation of the replication fidelity under different process conditions. Moreover, considerations on the warpage of parts were related to a manufacturing signature of the molding processes. At last, the global part mass average and standard deviation were measured to correlate local geometrical replication performances with global part quality trends.

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22

Basir, Al, Abu Bakar Sulong, Nashrah Hani Jamadon y Norhamidi Muhamad. "Bi-Material Micro-Part of Stainless Steel and Zirconia by Two-Component Micro-Powder Injection Molding: Rheological Properties and Solvent Debinding Behavior". Metals 10, n.º 5 (2 de mayo de 2020): 595. http://dx.doi.org/10.3390/met10050595.

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From the micro-powder injection molding (μPIM) process, a two-component micro-powder injection molding (2C-μPIM) process has evolved due to the growing demand for multi-functional micro-components in avant-garde applications. 2C-μPIM technology provides the opportunity to conjugate distinct materials within one part. Stainless steel (SS 17-4PH) and 3 mol.% yttria-stabilized zirconia (3YSZ) are characteristically recognized for their corrosion resistance and high hardness. In this work, the obtained critical powder volume concentration (CPVC) of SS 17-4PH and 3YSZ powders were 71.7 and 47.1 vol.%, respectively. Solid loadings of 2 and 3 vol.% less than the CPVC were considered as the optimal content for both powders. Feedstocks were obtained by mixing SS 17-4PH and 3YSZ powders with a binder system comprised of palm stearin (PS) and low-density polyethylene (LDPE). The rheological behaviors of the prepared feedstocks were assessed to figure out the feedstocks having the best rheological properties. The feedstocks of SS 17-4PH and 3YSZ with powder loadings of 69 and 44 vol.% were eventually injected to produce bi-material micro-parts. The optimal solvent debinding temperature of the green bi-material micro-part was then investigated, and it was found that 73.3% soluble binder was removed when bi-material was immersed in acetone at 70 °C for 40 min.

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23

John, Andreas. "Monte-Carlo Simulation of Compatibilization by Network-Building and Catalytic Interface Reactions in Two-Component Injection Molding". Open Macromolecules Journal 6, n.º 1 (27 de enero de 2012): 1–18. http://dx.doi.org/10.2174/1874343901206010001.

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24

Bex, Gert-Jan, David Seveno, Jozefien De Keyzer, Frederik Desplentere y Albert Van Bael. "Wetting measurements as a tool to predict the thermoplastic/thermoset rubber compatibility in two-component injection molding". Journal of Applied Polymer Science 135, n.º 13 (27 de noviembre de 2017): 46046. http://dx.doi.org/10.1002/app.46046.

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25

Persson, Anna‐Maria M. R., Einar L. Hinrichsen y Erik Andreassen. "Adhesion between thermoplastic elastomers and polyamide‐12 with different glass fiber fractions in two‐component injection molding". Polymer Engineering & Science 60, n.º 7 (28 de mayo de 2020): 1642–61. http://dx.doi.org/10.1002/pen.25408.

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Rajamani, Praveen Kannan, Tatyana Ageyeva y József Gábor Kovács. "Personalized Mass Production by Hybridization of Additive Manufacturing and Injection Molding". Polymers 13, n.º 2 (19 de enero de 2021): 309. http://dx.doi.org/10.3390/polym13020309.

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The new trend in the composites industry, as dictated by Industry 4.0, is the personalization of mass production to match every customer’s individual needs. Such synergy can be achieved when several traditional manufacturing techniques are combined within the production of a single part. One of the most promising combinations is additive manufacturing (AM) with injection molding. AM offers higher production freedom in comparison with traditional techniques. As a result, even very sophisticated geometries can be manufactured by AM at a reasonable price. The bottleneck of AM is the production rate, which is several orders of magnitude slower than that of traditional plastic mass production technologies. On the other hand, injection molding is a manufacturing technique for high-volume production with little possibility of customization. The customization of injection-molded parts is usually very expensive and time-consuming. In this research, we offered a solution for the individualization of mass production, which includes 3D printing a baseplate with the subsequent overmolding of a rib element on it. We examined the bonding between the additive-manufactured component and the injection-molded component. As bonding strength between the coupled elements is significantly lower than the strength of the material, we proposed five strategies to improve bonding strength. The strategies are optimizing the printing parameters to obtain high surface roughness, creating an infill density in fused filament fabrication (FFF) parts, creating local infill density, creating microstructures, and incorporating fibers into the bonding area. We observed that the two most effective methods to increase bonding strength are the creation of local infill density and the creation of a microstructure at the contact area of FFF-printed and injection-molded elements. This increase was attributed to the porous structures that both methods created. The melt during injection molding flowed into these pores and formed micro-mechanical interlocking.

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Scharvogel, Matthias. "Titanium Metal Injection Molding - A Commercial Overview". Key Engineering Materials 704 (agosto de 2016): 107–12. http://dx.doi.org/10.4028/www.scientific.net/kem.704.107.

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Metal Injection Molding (MIM) of Titanium and its alloys has been the topic of many scientific research activities and presentations for many years. By now there are several companies that focus on applying the gained knowledge for producing Titanium MIM components in production quantities. This is only possible since Titanium powder in repeatable quality is available in production quantities and the specialized production equipment was developed over the recent years. Two ASTM standards for Titanium MIM implants have published and several Titanium MIM components have received approval around the globe, including approval by the Food and Drug Administration (FDA) for the United States. Based on this foundation, several large Medical Technology companies started developing next generation implants using MIM as the preferred production method in order to use the design advantages and / or reduce costs. The aerospace industry also started recognizing the advantages of Titanium MIM. There are several Titanium MIM parts that are already being used in commercial airplanes in production quantities. Additional applications in order to replace other materials, reduce costs or use the design advantages of MIM are currently being developed. The cost reduction related to Titanium MIM allows the usage of this great material in other industries like for sporting goods, outdoor equipment or luxury products. The Titanium MIM industry is slowly maturing and large companies started applying the great advantages into the product portfolio. It will be imperative that the relatively small Titanium MIM companies perform according to the high expectations of the large potential customers that would like to use the technology for future products.

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Xi, Guan Nan, Miao Sun, Jun Gao y Yi Dan Zhou. "Analysis of Injection Molding Machine's Energy Consumption Based on Two Different Hydraulic Circuits". Applied Mechanics and Materials 365-366 (agosto de 2013): 220–23. http://dx.doi.org/10.4028/www.scientific.net/amm.365-366.220.

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As is known to all, domestic productions of injection molding machine are huge and exported to all over the world. However, the production can only occupy the low-end markets because of its high-energy consumption and low molding precision. Besides the problems of mechanical components, the main reason led to such results lie in the its too backward hydraulic system. By comparing domestic traditional hydraulic system with foreign new hydraulic servo system, this paper focuses on the analysis of the characteristics of foreign new hydraulic servo system and verify the results by experiments based on the upper two different hydraulic system. Through this paper hopefully can it provide some practical directs to the design of domestic new hydraulic system.

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Liparoti, Sara, Vito Speranza y Roberto Pantani. "Replication of Micro- and Nanofeatures in Injection Molding of Two PLA Grades with Rapid Surface-Temperature Modulation". Materials 11, n.º 8 (15 de agosto de 2018): 1442. http://dx.doi.org/10.3390/ma11081442.

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The production by injection molding of polymeric components having micro- and nanometrical surfaces is a complex task. Generally, the accurate replication of micro- and nanometrical features on the polymeric surface during the injection-molding process is prevented by of the low mold temperature adopted to reduce cooling time. In this work, we adopt a system that allows fast heating of the cavity surface during the time the melt reaches the cavity, and fast cooling after heater deactivation. A nickel insert with micro- and nanofeatures in relief is located on the cavity surface. Replication accuracy is analyzed by Atomic Force Microscopy under different injection-molding conditions. Two grades of polylactic acid with different viscosity have been adopted. The results indicate that the higher the cavity surface temperature is, the higher the replication accuracy is. The viscosity has a significant effect only in the replication of the microfeatures, whereas its effect results are negligible in the replication of nanofeatures, thus suggesting that the interfacial phenomena are more important for replication at a nanometric scale. The evolution of the crystallinity degree on the surface also results in a key factor on the replication of nanofeatures.

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30

Bex, Gert-Jan, Wim Six, Brittany Laing, Jozefien De Keyzer, Frederik Desplentere y Albert Van Bael. "Effect of process parameters on the adhesion strength in two-component injection molding of thermoset rubbers and thermoplastics". Journal of Applied Polymer Science 135, n.º 29 (10 de abril de 2018): 46495. http://dx.doi.org/10.1002/app.46495.

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31

Liberati, João Franklin, Oscar O. Araujo Filho, Waldemar Alfredo Monteiro, Iara M. Esposito, Rejane A. Nogueira y Francisco Ambrozio Filho. "Low-Pressure Injection Molding Processing of AISI T15 High Speed Steel Powders". Materials Science Forum 514-516 (mayo de 2006): 569–73. http://dx.doi.org/10.4028/www.scientific.net/msf.514-516.569.

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Low-pressure powder injection molding was used to obtain AISI T15 high speed steel parts. The binders used were based on paraffin wax, low density polyethylene and stearic acid. The metals powders were characterized in terms of morphology, particle size distribution. The mixture was injected in the shape of square bar specimens to evaluate the performance of the injection in the green state, and then sintered. The samples were injected under the pressures of 0.4, 0.5 and 0.7MPa and at temperatures varying from 110 to 150°C aiming the optimization of the process. The results of the variation of injection pressure were evaluated by measuring the density of the green parts. Debinding was carried out in two steps: first, the molded part was immersed in heptane to remove the major component of the binder and then heated to remove the remaining binder. A second step debinding and sintering were performed in a single step. This procedure shortened considerably the debinding and sintering time.

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32

Long, Jing, Bing Bing Chen, Chun Liang Zhang y Liang Liang Zhang. "Heat Pipe Cooling Scheme Analysis of Injection Molding Machine Controller". Applied Mechanics and Materials 441 (diciembre de 2013): 150–53. http://dx.doi.org/10.4028/www.scientific.net/amm.441.150.

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In the long run, the problem of high temperature has been existed in a companys injection molding machine controller. In order to solve the heat dissipation problem, two kinds of heat pipe heat dissipation schemes are designed, CFD software ICEPAK is used in the report to make a numerical simulation as well as a simulation analysis of the Heat pipe cooling scheme. By comparing two kinds of cooling mode heat pipe cooling effect and structure process, Vertical-type heat pipe cooling solution that meets the cooling requirements and makes heat-sensitive components stay away from high-temperature, furthermore heat pipe processing technology is relatively simple.

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33

John, Andreas. "Compatibilization in Two-Component Injection Molding by Means of Split Reactions with Varying Reactive Sites – a Monte-Carlo Simulation". Open Macromolecules Journal 5, n.º 1 (9 de mayo de 2011): 1–12. http://dx.doi.org/10.2174/1874343901105010001.

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34

Laing, Brittany, Jozefien De Keyzer, David Seveno y Albert Van Bael. "Adhesion between ethylene‐propylene‐diene monomer and thermoplastics in two‐component injection molding: Effect of dicumylperoxide as curing agent". Journal of Applied Polymer Science 137, n.º 41 (23 de marzo de 2020): 49233. http://dx.doi.org/10.1002/app.49233.

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35

Nötzel, Dorit y Thomas Hanemann. "New Feedstock System for Fused Filament Fabrication of Sintered Alumina Parts". Materials 13, n.º 19 (8 de octubre de 2020): 4461. http://dx.doi.org/10.3390/ma13194461.

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Only a few 3D-printing techniques are able to process ceramic materials and exploit successfully the capabilities of additive manufacturing of sintered ceramic parts. In this work, a new two component binder system, consisting of polyethyleneglycol and polyvinylbutyral, as well stearic acid as surfactant, was filled with submicron sized alumina up to 55 vol.% and used in fused filament fabrication (FFF) for the first time. The whole process chain, as established in powder injection molding of ceramic parts, starting with material selection, compounding, measurement of shear rate and temperature dependent flow behavior, filament fabrication, as well as FFF printing. A combination of solvent pre-debinding with thermal debinding and sintering at a reduced maximum temperature due to the submicron sized alumina and the related enhanced sinter activity, enabled the realization of alumina parts with complex shape and sinter densities around 98 % Th. Finally the overall shrinkage of the printed parts were compared with similar ones obtained by micro ceramic injection molding.

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36

Medesi, Anna Julia, Dorit Nötzel y Thomas Hanemann. "PVB/PEG-Based Feedstocks for Injection Molding of Alumina Microreactor Components". Materials 12, n.º 8 (14 de abril de 2019): 1219. http://dx.doi.org/10.3390/ma12081219.

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The ceramic injection molding (CIM) process is a cost-effective powder-based near net shape manufacturing process for large-scale production of complex-shaped ceramic functional components. This paper presents the rheological analysis of environmentally friendly CIM feedstock formulations based on the binder components polyvinyl butyral (PVB) and polyethylene gycol (PEG). The prepared PVB/PEG-based alumina molding compounds were investigated with respect to their PVB:PEG ratios as well as to their powder filling degrees in the range between 50 and 64 vol.%. Corresponding viscosities and shear stresses were determined for increasing shear rates to show the effects of increased PEG content and solid loadings on them. Two single reactor components were injection molded and subsequently joined in their green state for fabrication of an alumina microreactor. The intended purpose of the alumina microreactors is their potential application as wear-resistant and hydrothermal stable multifunctional devices (µ-mixer, µ-reactor, µ-analyzer) for continuous hydrothermal synthesis (CHTS) of metal oxide nanoparticles in supercritical water (sc-H2O) as the reaction medium.

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37

Wang, Jing, Zheng Cai Wang, Li Ying Xue y Li Zhu Liu. "Optimization Design for MA5300 Injection Molding Machine’s Clamping Unit’s Hydraulic System". Applied Mechanics and Materials 321-324 (junio de 2013): 1770–74. http://dx.doi.org/10.4028/www.scientific.net/amm.321-324.1770.

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Focusing on PET perform molding features, working principles of MA5300 Injection Molding Machine’s clamping unit’s hydraulic system has been analyzed in this paper. Based on previous hydraulic system, magnetic exchange valve has been added on the demoulding hydraulic circuit, demolding speed has been fastened; energy accumulator has been added on the control circuit so as to stabilize controlled oil-source, improve time of opening and clamping mould and response speed. In addition, common one-way valve in core oil circuit is replaced with hydraulic control one-way valve, in order to realize pressure maintaining function; hydraulic insurance structure is changed into inner circulation, and two-way cartridge valve is used as security valve, so as to realize faster response, and largely improved equipment security. Through adopting common hydraulic components, under the premise of limited increasing cost, the injection molding cycle for PET perform product has been reduced, and enterprise’s productivity has been improved.

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38

Fernandez, Angel y Manuel Muniesa. "Influence of Packing Phase Parameters in the Optimization of Mechanical, Weight Reduction and Dimensional Properties of Microcellular Foaming Injection Molding of Polypropilene". Advanced Materials Research 445 (enero de 2012): 319–24. http://dx.doi.org/10.4028/www.scientific.net/amr.445.319.

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Microcellular foaming of injected plastics offers the possibility to manufacture parts with reductions in costs and weight if compared with conventional injection molding. For this reason there is an increasing interest in challenging applications such as HEV (hybrid and electrical vehicles) and lightweight material applications in general. Complexity of microcellular injection molding is very high because the final properties of the material obtained depend largely on the processing conditions and these in turn unalterable factors such as mold design and manufacturing. The shrinkage of the molded part must be applied as an oversize of the mold cavity in the design phase. Shrinkage of a microcellular foam depends on the reduction of foam density. Moreover, the piece is designed to get a mechanical performance and meet the dimensional tolerances. Knowing that the reduction of foam density implies a reduction of the mechanical properties and influences the final piece dimensions the conclusion is that the microcellular injection process has a very small process window to fit all these factors. This research focuses on two objectives. First is the variation of post-molding shrinkage in terms of reduction of weight to determine the process window. Second is the determination of mechanical properties which do not show a proportional reduction but exponentially with weight reduction components. The results obtained with a 750 Tons. injection moulding machine equipped with a MuCell plastication unit and a large spiral mold have shown small variations in the dimensions for a predetermined process window and smaller reduction of mechanical properties with weight reductions for 20% talc filled polypropylene. The goal of this applied research is that all experiments have been developed with scaled-industry tools (large injection molding machine, Mucell unit and mold and test parts) comparing with conventional injection molding.

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39

Basir, Al, Abu Bakar Sulong, Nashrah Hani Jamadon y Norhamidi Muhamad. "Feedstock properties and debinding mechanism of yttria-stabilized zirconia/ stainless steel 17-4PH micro-components fabricated via two-component micro-powder injection molding process". Ceramics International 47, n.º 14 (julio de 2021): 20476–85. http://dx.doi.org/10.1016/j.ceramint.2021.04.057.

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40

Laing, Brittany, Jozefien De Keyzer, David Seveno y Albert Van Bael. "Effect of co‐agents on adhesion between peroxide cured ethylene–propylene–diene monomer and thermoplastics in two‐component injection molding". Journal of Applied Polymer Science 137, n.º 9 (20 de agosto de 2019): 48414. http://dx.doi.org/10.1002/app.48414.

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41

Hotaka, Toshiaki, Yasuhiro Sugihara, Akihiro Nitta, Tomomitsu Onizawa y Katsuhito Fukushima. "Integrated Large-area Panoramic Roof & Automotive Body Panel by Two-component Injection-press Molding with 4-axis Parallelism Control". Seikei-Kakou 20, n.º 9 (20 de agosto de 2008): 665–69. http://dx.doi.org/10.4325/seikeikakou.20.665.

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42

Giannekas, Nikolaos, Yang Zhang y Guido Tosello. "Investigation on Product and Process Fingerprints for Integrated Quality Assurance in Injection Molding of Microstructured Biochips". Journal of Manufacturing and Materials Processing 2, n.º 4 (15 de noviembre de 2018): 79. http://dx.doi.org/10.3390/jmmp2040079.

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Injection molding has been increasing for decades its share in the production of polymer components, in comparison to other manufacturing processes, as it can assure a cost-efficient production while maintaining short cycle times. In any production line, the stability of the process and the quality of the produced components is ensured by frequently performed metrological controls, which require a significant amount of effort and resources. To avoid the expensive effect of an out of tolerance production, an alternative method to intensive metrology efforts to process stability and part quality monitoring is presented in this article. The proposed method is based on the extraction of process and product fingerprints from the process regulating signals and the replication quality of dedicated features positioned on the injection molded component, respectively. The features used for this purpose are placed on the runner of the moldings and are similar or equal to those actually in the part, in order to assess the quality of the produced plastic parts. For the purpose of studying the method’s viability, a study case based on the production of polymer microfluidic systems for bio-analytics medical applications was selected. A statistically designed experiment was utilized in order to assess the sensitivity of the polymer biochip’s micro features (μ-pillars) replication fidelity with respect to the experimental treatments. The main effects of the process parameters revealed that the effects of process variation were dependent on the position of the μ-pillars. Results showed that a number of process fingerprints follow the same trends as the replication fidelity of the on-part μ-pillars. Instead, only one of the two on-runner μ-pillar position measurands can effectively serve as product fingerprints. Thus, the method can be the foundation for the development of a fast part quality monitoring system with the potential to decrease the use of off-line, time-consuming detailed metrology for part and tool approval, provided that the fingerprints are specifically designed and selected.

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43

Fareh, Faoud, V. Demers, S. Turenne y O. Scalzo. "Segregation Measurement of Inconel 718 Feedstocks Used in Low-Pressure Metal Injection Molding". Materials Science Forum 857 (mayo de 2016): 286–90. http://dx.doi.org/10.4028/www.scientific.net/msf.857.286.

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Low-pressure metal injection molding (LP-MIM) is an advanced manufacturing technology where a wax-based feedstock is injected into a complex shape before densification heat treatments. Feedstock is generally designed to minimize segregation, maximize flowability, maximize the strength of the molded component, maximize the solid loading potential and ease of debinding. In this study, the emphasis is placed on the evaluation of the effect of segregation on different wax-based Inconel 718 superalloy feedstocks used in LP-MIM. In powder metallurgy, particle or phase segregation generates a fluctuation of the particle distribution in powder-binder mixtures from point to point. Such demixing generally occurs before or during the injection process, and can lead to the formation of defects such as cracks, distortions or heterogeneous shrinkage of the sintered parts. Different wax-based feedstocks were poured in cylindrical hot molds (95°C), maintained in molten state for 1 minutes or for 60 minutes, and rapidly cooled to room temperature. The specimens were then extracted from the top and bottom regions of each cylindrical part. A thermogravimetric analysis technique was used to measure the volume fraction of powder at these two locations in order to quantify the degree of segregation in green parts. The best candidate feedstocks minimizing segregation are the mixtures containing only paraffin wax, or those containing paraffin wax and ethylene vinyl acetate combined. An increase in the time spent in the molten state and the use of beeswax or stearic acid promote the powder-binder separation of feedstocks.

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44

Kazmer, David O., Davide Masato, Leonardo Piccolo, Kyle Puleo, Joshua Krantz, Varun Venoor, Austin Colon et al. "Multivariate Modeling of Mechanical Properties for Hot Runner Molded Bioplastics and a Recycled Polypropylene Blend". Sustainability 13, n.º 14 (20 de julio de 2021): 8102. http://dx.doi.org/10.3390/su13148102.

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Four sustainable materials including a recycled polypropylene blend, polybutylene adipate terephthalate, and two grades of polylactic acid are compared to a reference isotactic polypropylene. Tensile specimens were produced using a two-cavity, hot runner mold with fully automatic cycles per standard industrial practices to investigate the effect of melt temperature, injection velocity, cycle time, and screw speed on the mechanical properties. Multiple regression and principal component analyses were performed for each of the materials. Results indicated that all the materials were readily processed using a hot runner, and the mechanical properties exhibited minimal variation. To the extent that losses in mechanical properties were observed, the results indicated that the losses were correlated with thermal degradation as independently characterized by thermal gravimetric analysis. Such losses can be minimized by reducing melt temperature and cycle time, leading to a reduction of the environmental impact of injection molding processes.

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45

Calaon, Matteo, Federico Baruffi, Gualtiero Fantoni, Ilenia Cirri, Marco Santochi, Hans Nørgaard Hansen y Guido Tosello. "Functional Analysis Validation of Micro and Conventional Injection Molding Machines Performances Based on Process Precision and Accuracy for Micro Manufacturing". Micromachines 11, n.º 12 (16 de diciembre de 2020): 1115. http://dx.doi.org/10.3390/mi11121115.

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Micro polymer parts can be usually manufactured either by conventional injection moulding (IM) or by micro-injection moulding (µIM). In this paper, functional analysis was used as a tool to investigate the performances of IM and µIM used to manufacture the selected industrial component. The methodology decomposed the production cycle phases of the two processes and attributed functions to parts features of the two investigated machines. The output of the analysis was aimed to determine casual chains leading to the final outcome of the process. Experimental validation of the functional analysis was carried out moulding the same micro medical part in thermoplastic elastomer (TPE) material using the two processes by means of multi-cavity moulds. The produced batches were assessed using a precision scale and a high accuracy optical instrument. The measurement results were compared using capability indexes. The data-driven comparison identified and quantified the correlations between machine design and part quality, demonstrating that the µIM machine technology better meets the accuracy and precision requirements typical of micro manufacturing productions.

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46

Grimm-Strele, Hannes, Matthias Kabel y Jonathan Köbler. "Efficient Characterization and Modelling of Material Behaviour of LFT for Component Simulations". Key Engineering Materials 809 (junio de 2019): 447–51. http://dx.doi.org/10.4028/www.scientific.net/kem.809.447.

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Modeling failure and progressive damage of long fibre reinforced thermoplastics (LFT) presents a challenging task since local inhomogeneities, anisotropic fibre orientations, and strain-rate dependence must be taken into account also on the microscale. We show that for simple geometries, the material behaviour of the composite can be modelled using layered geometrical models. But for more complex geometries, this approach fails since the fibre orientation distribution is inhomogeneous. In this case, multiscale methods allow the accurate and efficient prediction of the material behaviour with the local fibre orientation taken from an injection molding simulation. This material model can be extended to viscoplasticity and integrated into the NTFA-TSO method from Michel & Suquet (2016). In this way, we can obtain an accurate and efficient multiscale method for the realistic modelling of LFT.

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47

Karania, Ruchi y David Kazmer. "Low Volume Plastics Manufacturing Strategies". Journal of Mechanical Design 129, n.º 12 (31 de enero de 2007): 1225–33. http://dx.doi.org/10.1115/1.2790978.

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Plastic components are vital components of many engineered products, frequently representing 20–40% of the product value. While injection molding is the most common process for economically producing complex designs in large quantities, a large initial monetary investment and extended development time are required to develop appropriate tooling. For applications with lower or unknown production quantities, designers may prefer another process that has a lower development cost and lead time albeit with higher marginal costs and production times. A methodology is presented that assists the designer to select the most appropriate manufacturing process that trades off the total production costs with production lead times. The approach is to develop aggregate component cost and lead-time models as a function of production quantity from extensive industry data for an electrical enclosure consisting of two components. Binding quotes were secured from multiple suppliers for a variety of manufacturing processes including computer numerical control machining, fused deposition modeling, selective laser sintering, vacuum casting, direct fabrication, and injection molding with soft prototype and production tooling. The methodology yields a Pareto optimal set that compares the production costs and lead times as a function of the production quantity. The results indicate that the average cost per enclosure assembly is highly sensitive to the production quantity, with average costs varying by more than a factor of 100 for production quantities varying between 100 and 10,000 assemblies. Each of the processes is competitive with respect to total production cost and total production lead time under differing conditions; a flow chart is provided as an example of a decision support tool that can be provided to assist process selection during the product development process and thereby reduce the product development time and cost.

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48

Kuhn, Christoph y Simon Wehler. "A Force-Balanced Fiber Retardation Model to Predict Fiber-Matrix-Separation during Polymer Processing". Journal of Composites Science 4, n.º 4 (1 de noviembre de 2020): 165. http://dx.doi.org/10.3390/jcs4040165.

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The use of discontinuous fiber reinforced composites in injection and compression molding faces a number of challenges regarding process-induced changes in microstructure, which have a significant influence on the mechanical properties of the final component. The changes in final microstructure are caused by complex fiber movements, such as fiber orientation, attrition and accumulation during flow. While there are existing phenomenological prediction models for both fiber orientation and attrition, the prediction of fiber accumulation due to fiber-matrix separation is currently only possible with a complex mechanistic particle simulation, which is not applicable in industrial simulations. A simplified phenomenological model, the fiber retardation model (FRM), for the prediction of fiber-matrix separation in commercially available software tools is presented in this paper. The model applies a force balance onto an interacting two phase flow of polymer melt and fiber phase and applies a retardation factor Κ to calculate the slowing and accumulation of the fiber phase. The general model is successfully applied to a simple compression molding simulation.

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49

Oelsch, Erik, Ralf Landgraf, Lysander Jankowsky, Martin Kausch, Stefan Hoyer, Welf-Guntram Drossel y Jörn Ihlemann. "Comparative investigation on the mechanical behavior of injection molded and 3D-printed thermoplastic polyurethane". Journal of Rubber Research 24, n.º 2 (26 de marzo de 2021): 249–56. http://dx.doi.org/10.1007/s42464-021-00092-w.

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Abstract3D printing opens up new possibilities for the production of polymeric structures that would not be possible with injection molding. However, it is known that the manufacturing method might have an impact on the mechanical properties of manufactured components. To this end, the mechanical behavior of test specimens made of thermoplastic polyurethane is compared for two different manufacturing methods. In particular, the SEAM technology (screw extrusion additive manufacturing) is compared to a conventional injection molding process. Uniaxial tension test specimens from both manufacturing methods are analyzed in two testing sequences (multi-hysteresis tests to analyze inelastic properties and uniaxial tension until rupture). To get as less perturbation as possible, the 3D-printed samples are printed with only one strand per layer. Moreover, a correction approach based on optical measurements is applied to determine the true cross-sectional area of the test specimens. The mechanical tests reveal that the inelastic material behavior is the same for both manufacturing methods. Instead, 3D-printed specimens show lower maximal stretch values at rupture and an increased variance in the results, which is related to the surface structure of 3D-printed specimens.

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50

Welschinger, Fabian, Jonathan Köbler, Heiko Andrä, Ralf Müller, Matti Schneider y Sarah Staub. "Efficient Multiscale Methods for Viscoelasticity and Fatigue of Short Fiber-Reinforced Polymers". Key Engineering Materials 809 (junio de 2019): 473–79. http://dx.doi.org/10.4028/www.scientific.net/kem.809.473.

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To predict the nonlinear mechanical behavior of components made of short fiber-reinforced plastics (SFRP) under long term and cyclic loading, coupled process and component simulations are required. The injection molding process leads to locally varying fiber orientations within the component. This varying microstructure [1] significantly influences the viscoelastic and fatigue behavior. The interaction between the microstructure [2] and the nonlinear macroscopic properties is resolved by a coupled fast Fourier transformation and finite element two-scale method (FFT-FEM), where the fiber orientation tensor is obtained by analyzing μCT images or by the corresponding process simulation. The aim of this work is to reduce the numerical costs of such a multiscale method. In a first step, the highly efficient micro-scale solver FeelMath [3,4] using an FFT-based preconditioner is presented. Afterwards, a numerical scheme based on a precomputed database trained with FeelMath simulations on the microscale and a model order reduction algorithm, is discussed. The combination of these ideas reduces the numerical effort, such that the method is applicable for industrial problems. Comparative studies of the fully coupled and reduced model document the high accuracy of this approach. The overall performance of this methodology is demonstrated by three-dimensional, industrial applications.

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