Dissertations / Theses on the topic 'Printing forms'
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Palazzolo, Robert D. (Robert David) 1973. "Formulation of oral dosage forms by three dimensional printing." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50617.
Full textIncludes bibliographical references (p. 93).
Pharmaceutical grade materials were used in the fabrication of fast-release and extended-release oral dosage forms. Tablets were processed by employing a method of solid freeform fabrication known as three dimensional printingTM (3DPTM). A microcrystalline cellulose powder was used in combination with pH-dependent and permeable polymeric binder solutions. Release studies in acidic media were performed using both dye and drug (antihistamine) as actives. Deposition was performed by micro pipette into concept devices. It was concluded that printing parameters could be used to control the microstructure and release behavior. The performance of a drop-on-demand inkjet printing system was evaluated to be highly accurate, and the system was used in the fabrication of model oral dosage forms. Tablets were constructed with a permeable polymer as binder. Mechanical tests showed that the tablets were comparable to industry references for both strength and friability. A USP dissolution method involving an acid and buffer stage was used for extended-release studies. Release by diffusion was found to depend on device porosity level and drug distribution as defined during fabrication.
by Robert D. Palazzolo.
S.M.
Kyobula, Mary. "Manufacturing of oral solid dosage forms using 3D inkjet printing." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/42980/.
Full textTennberg, Hannes. "WOODEN : in other forms." Thesis, Konstfack, Inredningsarkitektur & Möbeldesign, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-6347.
Full textKatstra, Wendy E. (Wendy Ellen) 1974. "Fabrication of complex oral drug delivery forms by Three Dimensional Printing (tm)." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/32709.
Full textIncludes bibliographical references (p. 237-241).
Three Dimensional Printing 3DPTM is a novel solid freeform fabrication technology that has been applied to the fabrication of complex pharmaceutical drug devices. Limitations of the technology as relating to pharmaceuticals have been addressed and prototype dosage forms have been fabricated. The resolution of the 3DP tablets was found to depend on particle size and liquid migration during printing and drying. The surface finish of 3DP tablets was enhanced by uniaxial pressing. Migration inhibiting additives were effective in limiting transport. Both aqueous and ethanol-based solutions showed a decrease in migration on the order of 20% when appropriate powder bed additives were introduced. Migration was also decreased by pre-printing barriers to confine secondary printed drug solutions. Low dosage forms were fabricated with as little as 2.3 nanograms. Lower dosages are expected upon dilution of the initial drug solution. Printing forms with high dosage is limited by powder void volume, filling efficiency, and drug solubility limits. Multiple print passes increased the dosage per tablet volume, 6, at the expense of process time. The use of drug suspensions to overcome solubility limits and uniaxial compression to reduce tablet volume was shown to significantly increase 6. The highest 8 achieved was 427 mg/cc for pressed suspension-printed tablets, representing 74% of the theoretical limit. Complex oral dosage forms were fabricated with 3DP to show lagged-release, extended-release, double-release, and zero-order-release. Release properties, such as lag time and release rate, were manipulated by varying the printing parameters.
(cont.) Dual-release and zero-order-release forms were fabricated using a surface degradation/erosion system based on HPMC, lactose, and Eudragitʾ L100. Erosion rate constants were used to model release from tablets with non-uniform drug distributions. Diclofenac and chlorpheniramine dual-release tablets were designed with 3 drug regions, and dissolution of the tablets followed the model closely, exhibiting 2 onsets. Two types of zero-order tablets were invented and fabricated by 3DP. These contained drug concentration gradients designed to complement the volumetric nonuniformity of eroding shells. Three formulations showed constant release of diclofenac sodium over 1-7 hours (9.6mg/hr), 1-15 hours (6.8mg/hr), and 1-36 hours (2.5mg/hr).
by Wendy E. Katstra.
Ph.D.
Khaled, Shaban. "Extrusion based 3D printing as a novel technique for fabrication of oral solid dosage forms." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/38437/.
Full textEl, Aita Ilias [Verfasser], Jörg [Gutachter] Breitkreutz, and Peter [Gutachter] Kleinebudde. "Manufacturing solid dosage forms using pressure-assisted microsyringe 3D-printing / Ilias El Aita ; Gutachter: Jörg Breitkreutz, Peter Kleinebudde." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2021. http://d-nb.info/1232490059/34.
Full textВихристюк, Ольга Володимирівна. "Поліграфічне підприємство з дослідженням технології виготовлення етикеткової продукції." Master's thesis, КПІ ім. Ігоря Сікорського, 2021. https://ela.kpi.ua/handle/123456789/46346.
Full textThe explanatory note to the master's dissertation on the topic "Printing company with research on the technology of manufacturing label products" consists of 112 pages, containing 7 sections and subsections. The total number of illustrations is 49, tables - 52, the number of sources according to the list of references 33. The master's dissertation consists of seven main sections, which reveal in detail the main technical, design features of labels, selected the necessary equipment and materials for the manufacture of label products. All processes of manufacturing label products are analyzed, starting from the choice of printing method, necessary printing equipment, pre-printing processes, technology of manufacturing printing plates, and ending with post-printing processing. The general block diagram of technological processes of production of label products is developed. The main technical and economic indicators are calculated. The analysis of patent information showed that the development of improved technologies for the manufacture of label products is carried out in the future. However, within such trends, too little attention is paid to control methods, which, of course, is an important area of further research, as it will significantly improve the quality of reproduction of printed products. In the experimental part of the master's dissertation the research task was set, where it was determined that the improvement of the label manufacturing process is necessary to improve the technology of label production, in particular, defects in label manufacturing were investigated.
Объяснительная записка к магистерской диссертации по «Полиграфическое предприятие с исследованием технологии изготовления этикеточной продукции» состоит из 112 страниц, содержащих 7 разделов и подразделы. Общее количество иллюстраций составляет 49, таблиц – 52, количество источников согласно ссылкам 33. Магистерская диссертация состоит из семи основных разделов, где подробно раскрыты главные технические, конструкторские особенности этикеток, выбрано необходимое оборудование и материалы для изготовления этикеточной продукции. Проанализированы все процессы изготовления этикеточной продукции, начиная от выбора способа печати, необходимого печатного оборудования, допечатных процессов, технологии изготовления печатных форм и заканчивая послепечатной обработкой. Разработана общая блок-схема технологических процессов изготовления этикеточной продукции. Рассчитаны главные технико-экономические характеристики. Проведенный анализ патентной информации показал, что разработки по совершенствованию технологий при изготовлении этикеточной продукции проводятся и в дальнейшем. Однако в рамках таких тенденций слишком мало внимания уделено именно методам контроля, что безусловно является актуальным направлением дальнейших научных исследований, так как позволит существенно улучшить качество воспроизведения полиграфической продукции. В экспериментальной части магистерской диссертации осуществлена постановка задачи исследования, где определено, что усовершенствование процесса изготовления этикеточной продукции необходимо для улучшения технологии изготовления этикеточной продукции, в частности, были исследованы дефекты при изготовлении этикеточной продукции и исследованы цветовые показатели пантонного цвета при печатании тиража.
Korte, Carolin [Verfasser], Jörg [Gutachter] Breitkreutz, Peter [Gutachter] Kleinebudde, and Julian [Akademischer Betreuer] Quodbach. "3D-Drug-Printing: Extrusion of Printable Drug-Loaded Filaments and Development of Novel Solid Dosage Forms / Carolin Korte ; Gutachter: Jörg Breitkreutz, Peter Kleinebudde ; Betreuer: Julian Quodbach." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2019. http://d-nb.info/1182032192/34.
Full textAl-Ansari, Banan Ahmed. "Interrelated Histories, Practices, and Forms of Communication: Using Arabic Calligraphy to Learn Arabic Typography." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804911/.
Full textSundaram, Subramanian Ph D. Massachusetts Institute of Technology. "3D-printing form and function." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120416.
Full textCataloged from PDF version of thesis.
Includes bibliographical references (pages 153-171).
Integrating diverse functions inside man-made parts with specific shapes, in a highly scalable manner, is the central challenge in manufacturing. Functional integration is typically achieved by assembling specialized parts, each independently made using carefully designed production techniques - for example, in assembly lines in the automotive industry. Externally assembling specialized parts is tedious at certain length scales (e.g. mesoscale manufacturing), imposes restrictions on achievable geometries, and limits functional integration. In contrast, nature excels at packing disparate materials and functions into unconstrained geometries across different length scales (e.g. distributed sensors in cuttlefish, or sensorimotor pathways and resonant muscles in insects). These far exceed our current fabrication capabilities, and replicating all the functions of natural systems has remained a distant dream. 3D-printing has resolved many challenges in fabricating complex geometries, but despite its promise, assembling diverse materials (including solids, liquids and thin-films) and functions inside a single, printed composite is a current challenge. This thesis presents a set of materials, processes and design strategies - a full experimental toolkit - to address the question: how can we distribute diverse materials and functions in free-form geometries? First, a fully-3D-printed autonomous composite that can sense an external stimulus, process it, and respond by varying its optical transparency is described. The composite consists of seamlessly integrated solids (UV-cured polymers), thin-films (conducting and semiconducting, solvent-evaporated films), and encapsulated liquids. Techniques to engineer material interfaces are also presented in this section. A stimulus-free strategy to 3D-print self-folding composites at room temperature is presented in the second part of this thesis. Specifically, the focus is on printing flat electrical composites that fold into pre-programmed shapes after printing using residual stress defined in specific regions. This provides advantages in the fabrication speed, and also expands the range of achievable geometries when using solvent-based inks. The third portion of this thesis focuses on 3D-printing soft actuators. After highlighting a few example applications of printed actuator arrays, this is used as a case study for topology optimization based design strategies. It is shown that the inclusion of a topology optimizer in the 3D-printing pipeline enables the automated design and fabrication of high-dimensional designs. The final section of this work focuses on creating tactile sensor arrays, with an emphasis on the acquisition of tactile datasets that can be used to understand the human grasp. The concluding section summarizes the role of the fabrication strategies presented here in creating composites of increasing levels of autonomy and self-sufficiency.
by Subramanian Sundaram.
Ph. D.
Leines, Kevin B. "The influence of the position of a color control bar on a form when determining the most appropriate location to measure variability in solid ink density and dot gain of a printed product /." Online version of thesis, 1990. http://hdl.handle.net/1850/10926.
Full textVelebskaja, Aliona. "Fleksografinių spausdinimo formų paruošimo procesų tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100619_142601-44034.
Full textIn the MS thesis are analyzed procedures of the flexographic printing plates manufacturing. The peculiarities of the screening processes are revealed. The details of the workflow of the preparation of the originals (projects) for printing and the process of printing plates manufacturing are described. Experimentally is investigated the influence of the screening regimes on the quality of the printing plates using different photopolymeric plates. The best versions of the screening program for the particular cases were determined.
Abd, El Kader Magdy Ezzat. "Application of Hot-Melt Ink Jet Processes for Imaging at Offset Printing Form Cylinder." Doctoral thesis, Universitätsbibliothek Chemnitz, 2004. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200400092.
Full textDer Fortschritt im Bereich von Charakterisierung und Verständnis für Hot-melt Ink Jet Prozesse zur Bebilderung von Offsetdruckform-Zylindern ist ein Ergebnis dieser Forschung. Die Systematik dieser Arbeit basiert auf einem theoretischen Teil, um einen geeigneten Löschprozess auszuwählen. Der Löschprozess hängt von den Eigenschaften des Hot-melt Ink Jet Materials und der genutzten Aluminiumdruckoberfläche ab. Diese werden systematisch im Labormaßstab experimentell untersucht. Der thermische Prozess wurde einerseits durch Benetzbarkeitsprüfungen und anderseites durch Rasterelektronmikroskopaufnahmen bewertet.Der Ultraschallprozess ist ein nasser Löschprozess. Die Untersuchungen wurden in vier Stufen systematisch durchgeführt - Auswahl vom geeigneten Lösungsmitteln - Einflüsse von ausgewählten Lösungsmitteln auf nicht beschichtete und beschichtete Aluminium platten - Evaluation eines Ultraschalllöschprozesses - Validation eines Löschprozesses; zur Bewertung des Löschprozesses wurden mehrere Druckplattenproben bebildert und gelöscht Die Ergebnisse wurden durch UV/Vis Spektrometer, Kontaktwinkel, Profiliometrie und Visuelle Mikroskopie getestet
Abd-el-Kader, Magdy Ezzat. "Application of hot melt ink jet processes for imaging at offset printing form cylinder." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=970645775.
Full textAl-Hachami, Wathiq. "Investigation of pico-litre inkjet printing for nano-gram scale solid form screening of pharmaceuticals." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52031/.
Full textGissibl, Timo [Verfasser], and Harald [Akademischer Betreuer] Giessen. "3D printing of sub-micrometer accurate ultra-compact free-form optics / Timo Gissibl ; Betreuer: Harald Giessen." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2016. http://d-nb.info/1183678215/34.
Full textXu, Shang. "Investigations into the Form and Design of an Elbow Exoskeleton Using Additive Manufacturing." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/103204.
Full textMaster of Science
Wearing an exoskeleton should be easy and stress-free, but many of the available models are not ergonomic nor user-friendly. To make an exoskeleton that is inviting and comfortable to wear, various nontraditional methods are used. The arm exoskeleton prototype has a lightweight and ergonomic frame, the joints are soft and compact, the cable-driven system is safe and low-profile. This design also brings aesthetics to the exoskeleton which closes the gap between engineering and design.
Šimėnas, Mindaugas. "Ofsetinių spausdinimo formų paviršinių savybių tyrimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060616_153055-46277.
Full textHergel, Jean. "Synthèse de formes fabricables à partir de spécifications partielles." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0003/document.
Full textThe Rapid Manufacturing techniques that emerged from Rapid Prototyping techniques such as 3D printing or laser cutting allow to fabricate unique objects. However, the design of those objects with existing CAD software remain a difficult task: rapid prototyping processes impose constraints on the geometry of the model. This thesis presents a set of techniques that assist the user in the design of an object by taking into account the constraints of the fabrication process. To achieve this, the algorithm automatically performs part of the modelling process. The following problems have been tackled: First, I propose to improve the quality of 3D printed objects by minimizing defects that appear during the fabrication. The technique developed impacts only the algorithm that drives the printer. Then, I propose to help the user to take into account the fabrication constraints during the modelling process. My techniques rely on partial information about the shape that the user wants to fabricate like the 2D sketch of a mechanism or a parametric model of a furniture. The algorithm optimizes the initial shape to improve fabrication objectives(Wastage, etc.) Finally, in some cases, the user does not know how to operate dedicated software. In this case, I propose a synthesis technique of furniture from functionnal specification, e.g. loads that have to be supported in space
Svatík, Juraj. "Funkční pěny s gradientem hustoty." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401848.
Full textRoman, Julien. "Mise en forme de matériaux carbonés biosourcés par voie liquide." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0202/document.
Full textThis work is devoted to the preparation of new bio-based carbon materials. Carbon materials, such as carbon fibers used in composites, are mainly obtained from a petroleum precursor. These precursors are expensive and not compatible with a sustainable industry. The use of a bio-based precursor available in large quantities such as lignin makes it possible to overcome limitations of petroleum based precursors. The aromatic molecular structure and high carbon content of lignin make it an ideal candidate for the production of bio-based carbon material. Lignin could be transformed into various materials such as carbon nanofibers, twisted carbon nanofibers, or carbonized composite 3D structures. These materials have been obtained from innovative techniques such as electrospinning and 3D printing. Twisting of the lignin-based-carbon nanofibers allowed for measurements of their mechanical strength. The electrochemical properties of the lignin-based twisted carbon nanofibers are interesting for potential microelectrode applications. The low microstructural order of the carbon from the carbonized lignin has been improved. Graphitization treatment or addition of carbon nanofillers contributed to this improvement. The mechanical, structural and electrical properties of nanocomposite carbon nanofibers illustrate the influence of graphene oxide on lignin. A composite effect between these two components has been observed. The 3D printing of composite inks based on lignin and graphene oxide has been reported for the first time in order to elaborate dense, organized and electrically conductive 3D carbonized structures
Raimondo, Luna. "La stampa 4D e gli smart materials. Stato dell’arte e progettazione di un kit per scrittura Braille basato su fogli polimerici a memoria di forma." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full textDickman, Daina Elizabeth. ""I'd created my own truths by printing my zine." Women-written Perzines as a narrative form for disclosure and advice giving." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1406717512.
Full textJolly, Nicolas. "Filtres accordables volumiques à forts facteurs de qualité pour des applications spatiales." Thesis, Limoges, 2015. http://www.theses.fr/2015LIMO0103/document.
Full textAt a time when the amount of information and the number of users go through the roof in telecommunication market, the telecommunication systems tend to improve the management of their capacity by moving toward reconfigurable RF devices. However frequency and bandwidth allocated are still restricted. Regarding tunable OMUX filters, the actuation systems generally degrade the overall performances of the device and raise questions in terms of mechanic and thermic.We first demonstrated the feasability of a two state filter with constant narrowband, using a dielectric material (alumina) in rotation inside a metallic housing. Then, we suggested solutions to control both frequency and bandwidth with the translation of a ceramics. We deal with quality factor in the range of ten of thousands for these applications. Eventually, we validated some principle for tunable filters thanks to the efficiency of 3D plastic printer
Correia, Rodrigo Emanuel de Almeida. "De que forma estão os retalhistas a incorporar aplicações 3D no seu modelo de negócio? Caso de estudo." Master's thesis, Instituto Superior de Economia e Gestão, 2019. http://hdl.handle.net/10400.5/19203.
Full textCom os recentes desenvolvimentos tecnológicos cada vez de ciclos mais reduzidos aliados a uma incessante busca pela inovação, as empresas necessitam de tomar decisões que as permita distanciar-se e ao mesmo tempo diferenciar-se da concorrência. A tecnologia de impressão 3D é um tema cada vez mais discutido ao longo dos últimos anos pelas suas características promissoras face à manufatura tradicional, em grande parte potenciadas pelos avanços tecnológicos referidos anteriormente. No entanto, poucos estudos existem sobre a sua aplicação em outros contextos empresariais, como o caso do contexto retalhista. Ainda que existam alguns estudos abrangendo as aplicações da tecnologia em determinadas fases da cadeia de valor de uma empresa, são desconhecidos estudos que permitam analisar a impressão 3D no contexto retalhista na forma de serviço. A presente investigação pretende evidenciar as diferenças existentes no modelo de negócio de uma empresa retalhista antes e depois da implementação da tecnologia de impressão 3D. Para esse efeito, utilizou-se um modelo de análise que permitiu contrastar as diferenças ao nível do modelo de negócio e ao mesmo tempo equiparar os resultados com a literatura encontrada sobre o tema. Segundo os dados analisados, é possível chegar à conclusão de que a impressão 3D permitiu reestruturar o modelo de negócio existente na empresa de forma positiva, alterando todas as componentes que o compõem, permitindo também obter conclusões relativamente à sua viabilidade em contexto nacional.
With the recent technological developments in ever-shrinking cycles coupled with a relentless pursuit for innovation, companies need to make decisions that allow them to distance themselves while differing from the competition. 3D printing technology has been a subject that has been increasingly discussed over the last few years for its promising characteristics compared to traditional manufacturing, greatly enhanced by the technological advances. However, few studies exist about its application in other business contexts, such as the retail context. Although there are some studies covering the applications of technology in certain phases of the value chain of a company, studies that analyze 3D printing in the retail context as a service are unknown. This research aims to highlight the differences in the business model of a retail company before and after the implementation of 3D printing technology. For this, we used an analysis model that allowed us to contrast the differences at the business model level and at the same time to match the results with the literature found on the subject. According to the data analyzed, it is possible to conclude that 3D printing made it possible to restructure the existing business model in the company in a positive way, changing all its components, and also allowing conclusions to be reached regarding its feasibility in a national context.
info:eu-repo/semantics/publishedVersion
Liu, Eunice. "Design gráfico: processo como forma." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/16/16134/tde-14102013-154730/.
Full textCreativity in the use of printing, reproduction, engraving, graphic finishings, editorial, binding and material resources in graphic design, denominated processes, is the theme of this research. The investigation is originated by projects, product of disciplinary practice, and is documented by image, for visual science. Technical, formal (related to form), and project studies explore relationships between process and form, resulting in a repertoire of parameters and possibilities. Pure form is graphic and constructed form, material shaped by processes, means of production by which form is tooled. The knowledge of processes is project resources, and creative appropriations of them, qualify a good design
Živko, Pavlović. "Karakterizacija površinske strukture neštampajućih elemenata CtP termalne štamparske forme za ofset štampu." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2012. http://dx.doi.org/10.2298/NS20120519PAVLOVIC.
Full textDissertation gives an overview of the current state, research and theories ofprinting forms and influence of printing process on wearing of non-printingelements within the science community. The dissertation points out the continuousmonitoring of topographic changes of printing form non-printing elements to controlthe exploitation of a period of time and the process of reproduction. This workcontributes to new research with the analysis of large number of experimentalsamples and calculated correlations and represents an advance in thecomprehension of the surface wear mechanism of printing form non-printingelements and their influence on the tribological changes to the structure of thebase layer of aluminium and aluminium oxide.
Dumas, Jérémie. "Synthèse de formes contrôlable pour la fabrication digitale." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0008/document.
Full textThe main goal of this thesis is to propose methods to synthesize shapes in a controllable manner, with the purpose of being fabricated. As 3D printers grow more accessible than ever, modeling software must now take into account fabrication constraints posed by additive manufacturing technologies. Consequently, efficient algorithms need to be devised to model the complex shapes that can be created through 3D printing. We develop algorithms for by-example shape synthesis that consider the physical behavior of the structure to fabricate. All the contributions of this thesis focus on the problem of generating complex shapes that follow geometric constraints and structural objectives. In a first time, we focus on dealing with fabrication constraints, and propose a method for synthesizing efficient support structures that are well-suited for filament printers. In a second time, we take into account appearance control, and develop new by-example synthesis methods that mixes in a meaningful manner criteria on the appearance of the synthesized shapes, and constraints on their mechanical behavior. Finally, we present a highly scalable method to control the elastic properties of printed structures. We draw inspiration from procedural texture synthesis methods, and propose an efficient algorithm to synthesize printable microstructures with controlled elastic properties
Režnáková, Ema. "Příprava a charakterizace lehčených polymerních materiálů s hierarchickou celulární strukturou." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-414127.
Full textGarnault, Tristan. "Frittage par micro-ondes de céramiques mises en forme par impression 3D." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALI077.
Full textThis PhD thesis deals with the sintering by microwave heating of alumina and yttria doped zirconia ceramics, shaped by additive manufacturing (Robocasting). Microwave heating allows to apply short thermal cycles with a moderate energy cost in comparison with conventional heating method. The combination of 3D printing and microwave sintering is a complete processing route, suitable for shaping and densification of small series of complex parts, saving raw material, time and energy. The aim of this work is therefore to reliably couple these two processes by improving our understanding of microwave/matter interactions, and by developing regulation methods and adapted sintering devices.The methods of automatic regulation and temperature monitoring of microwave devices were first dealt with. The frequency instability of magnetron sources is an obstacle to the application of effective automatic control if it is not taken into account. Subsequently, the microwave coupling of alumina and zirconia was discussed. These two materials have a very different behaviour. Alumina, which is quasi-transparent, heats with difficulty under direct irradiation. Zirconia, on the other hand, has a behaviour that changes strongly with temperature, going from not very absorbent to reflective, making it difficult to control its direct heating. Taking into account the characteristics of microwave devices and the behaviour of materials, a method of assisted microwave heating is proposed, allowing the rapid and controlled sintering of parts with varied compositions and geometries. Complex parts have been successfully sintered using this process
Zhang, Chuan. "Aluminum foams composite : elaboration and thermal properties for energy storage." Thesis, Troyes, 2017. http://www.theses.fr/2017TROY0015/document.
Full textThe objective of this thesis is to study and optimize the manufacturing process of metal foams and the thermal behavior of the aluminum foam/phase change material (PCM) composite by experimental and numerical methods. The manufacturing process of open-cell aluminum foam is developed and optimized to precisely control the parameters of mufacturing. Two pore-scale models of high porosity aluminum foams (HPAF)/PCM composite and low porosity aluminum foams (LPAF)/PCM composite are established for numerical simulation. By simulating the melting process of a layer energy storage system, the HPAF/PCM and LPAFS/PCM composite are compared numerically in order to evaluate the energy storage performance. The results show that aluminum foam improves greatly the heat transfer process in PCM due to its high thermal conductivity. The porosity of aluminum foams could not only influence the melting process of composite but also the energy storage performance. Thanks to the collaboration with EPF, a new manufacturing method of periodic open-cell aluminum foams is developed based on 3D rapid tooling. The thermal behavior of the periodic open-cell aluminum foams/PCM composite is experimentally and numerically analyzed
Kaloda, Vít. "Výroba částí prototypových forem s využitím metod rapid prototyping." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417084.
Full textGráf, Radomír. "Návrh technologie výroby plastového programového kotouče." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230863.
Full textBossard, Cédric. "Elaboration et caractérisation d’un hybride organominéral à base de polycaprolactone et de bioverre sous forme de mousse macroporeuse pour la régénération osseuse." Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC068/document.
Full textThe increase in life expectancy results in the decline of seniors’ health conditions and the resurgence of chronic diseases. Among the expressions of senescence, disorders of the musculoskeletal system are particularly disabling and considerably accelerate the state of dependency. This is also the case for young people who suffer from traumatic injuries or pathologic conditions. Thus, about 2.2 million bone grafts are performed worldwide every year. Yet, the level of postoperative complications remains high and is estimated at 15% of surgical operations. These facts outline a major societal concern: animal-based materials present a risk of histocompatibility issues and pathogenicity that may lead to implant failure. This is the reason why research efforts focus on the development of synthetic biomaterials capable of promoting bone regeneration. Currently, commercialised bone substitutes are mainly made of bioactive “ceramics” (calcium phosphates, bioactive glass) that are known to be biocompatible, to spontaneously bond to bone tissues, to promote bone cell adhesion and finally to be bioresorbable. However, despite these remarkable properties, the brittleness of these materials limits their applications. An ingenious solution to this brittleness can be learned from the particular structure of bone tissue. Bone tissue intimately blends an inorganic phase, the bone mineral, which is made of apatite crystals (resorbable calcium phosphates), with an organic phase that is mainly collagen. Such a structure associates the stiffness of the inorganic part with the toughness of collagen fibres. Therefore, in order to obtain implants with mechanical properties similar to that of bone, the strategy consists in combining bioactive ceramics with organic matter. To this end, the Biomatériaux team from the Laboratoire de Physique de Clermont (LPC) recently developed an innovative process that allows the synthesis of tridimensional organic-inorganic hybrids comprised of bioactive glass and biocompatible polymer. The objective of the thesis was to exploit this process in order to develop a hybrid bone substitute with optimal properties. First of all, polycaprolactone was selected as the polymer, especially because of its adequate degradation rate for long-term applications such as bone regeneration. Then, the synthesis process was improved (in particular, the calcium source was changed), the macroporous structure was optimised and the organic-inorganic ratio was chosen. Afterwards, elements that are known to induce an osteogenic effect were incorporated in the hybrid at low doses (< 5% of total weight): an inorganic doping was performed using strontium ions and an organic doping was performed using nutrients such as fisetin or hydroxytyrosol. The resultant hybrid scaffolds were eventually characterised in vitro in order to determine their physicochemical and biological properties and in vivo in order to evaluate their performance. After 3 months of implantation in a mouse calvarial critical defect, results demonstrate the potential of this bone substitute: compared to the reference commercial material (treated bovine bone) that leads to a bone reconstruction of 16% (± 5%), the hybrid allows a reconstruction going from 32% (± 3%) when it is not doped, to 55% (± 7%) and even 58% (± 7%) when it is doped respectively with fisetin or strontium. This thesis paves the way to promising perspectives like the association of doping agents and the 3D printing of polycaprolactone-bioactive glass hybrid scaffolds
Wendling-Hivet, Audrey. "Simulation à l'échelle mésoscopique de la mise en forme de renforts de composites tissés." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0079.
Full textNowadays, manufacturers, especially in transport, are increasingly interested in integrating composite parts into their products. These materials have, indeed, many benefits, among which allowing parts mass reduction when properly operated. In order to manufacture these parts, several methods can be used, including the RTM (Resin Transfer Molding) process which consists in forming a dry reinforcement (preform) before a resin being injected. This study deals with the first stage of the RTM process, which is the preforming step. It aims to implement an efficient strategy leading to the finite element simulation of fibrous reinforcements at mesoscopic scale. At this scale, the fibrous reinforcement is modeled by an interlacement of yarns assumed to be homogeneous and continuous. Several steps are then necessary and therefore considered here to achieve this goal. The first consists in creating a 3D geometrical model of unit cells as realistic as possible. It is achieved through the implementation of an iterative strategy based on two main properties. On the one hand, consistency, which ensures a good description of the contact between the yarns, that is to say, the model does not contain spurious spaces or interpenetrations at the contact area. On the other hand, the variation of the yarn section shape along its trajectory that enables to stick as much as possible to the evolutive shape of the yarn inside the reinforcement. Using this tool and a woven architecture freely implementable by the user, a model representative of any type of reinforcement (2D, interlock) can be obtained. The second step consists in creating a 3D consistent hexahedral mesh of these unit cells. Based on the geometrical model obtained in the first step, the meshing tool enables to mesh any type of yarn, whatever its trajectory or section shape. The third step consists in establishing a constitutive equation of the homogeneous material equivalent to a fibrous material from the mechanical behavior of the constituent material of fibers and the structure of the yarn. Based on recent experimental and numerical developments in the mechanical behavior of fibrous structures, a new constitutive law is presented and implemented. Finally, a study of the different parameters involved in the dynamic/explicit scheme is performed. These last two points allow both to a quick convergence of the calculations and approach the reality of the deformation of reinforcements. The entire chain modeling/simulation of fibrous reinforcements at mesoscopic scale created is validated by numerical and experimental comparison tests of reinforcements under simple loadings
Trnovec, Bystrik. "Experimentelle Untersuchungen zur Schichtbildung im Tiefdruck mittels hydrophobierter Druckform mit Applikationsbeispielen aus dem Bereich der gedruckten OPV." Doctoral thesis, Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-209748.
Full textIn this work is described experimental research about layer forming from non-Newtonian fluids in gravure printing on non-porous substrates. The viscous fingering, caused through fluid dynamics at splitting of printed material should be decreased by hydrophobic-surface modification of gravure printing form. The aim was to print wave-free homogenous layers. To achieve comparable results, modified and pure form were used simultaneously to print the same material. The printed material was mainly PEDOT:PSS and other, which is used in printed electronics. The properties (surface tension, viscosity) of printed materials were varied by additives. Printing conditions were varied too. The characteristic of printed layers were studied: resistivity, roughness, density, etc. The results shows decreasing of waviness, roughness and viscous fingering in final layer through use of hydrophobic gravure printing form, compared to print results with common printing form. This can be applied not only in the field of printed electronics
Wendling, Audrey. "Simulation à l'échelle mésoscopique de la mise en forme de renforts de composites tissés." Phd thesis, INSA de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00961196.
Full textTaborda, Sérgio. "Percepção e presença-o corpo na escultura, cinema e biotecnologias." Master's thesis, Instituições portuguesas -- UNL-Universidade Nova de Lisboa -- FCSH-Faculdade de Ciências Sociais e Humanas, 1999. http://dited.bn.pt:80/29026.
Full textMusil, Jiří. "Hledání tvaru skořepinových konstrukcí." Doctoral thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-390254.
Full textGuesnet, Laura. "Développement de nouvelles architectures de piles à combustible SOFC tout cérine pour un fonctionnement à température réduite." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0218.
Full textWhen involving new solid oxide cells (SOCs) architectures, it’s possible to reduce their operating temperature. The objective of this thesis was therefore to develop innovative shaping processes in order to reduce the cell manufacturing steps number, also allowing to reduce their cost : the preparation of a porous/dense/porous support by tape-casting, then the infiltration of catalysts to obtain the electrodes was the chosen process. The porous/dense/porous support was only prepared with GDC10 (Ce0.9Gd0.1O2-δ) to avoid chemical reactivity issues between the various layers. During this thesis, two shaping methods were successively used: pressing/screen-printing/infiltration (1) then tape-casting/infiltration (2). In each case, the shaping parameters have been optimized in order to obtain the best electrochemical performances. The shaping method (1) was already part of a thesis topic at ICMCB regarding the oxygen side of the SOC, but it has been here improved regardin the hydrogen side: the collecting layer, the catalyst nature (NiO, CuO, yttrium doped ceria), infiltration rate. To reduce the number of required cycles and improve the impregnation quality, a new technique was used: the infiltration in supercritical medium. In the case of shaping (2), the specific parameters of the i) suspension preparation (additives nature, nature of the used balls/jar) and of the ii) porous/dense/ porous supports (debinding/sintering cycles) have made it possible to obtain polarization resistances very close to those obtained by shaping (1), despite slightly higher series resistances, probably in linkto some remaining carbon pollution. The parameters finally retained are: a phosphoric ester type dispersant, 90% of graphite added to shape the porous skeletons, a debinding performed at 800°C/6h under wet O2, and a whole sintering at 1450°C/3h
Hu, Xusheng. "Study of the Thermal Performance of Metal Foam and PCM Composite for Thermal Energy Storage." Thesis, Troyes, 2021. http://www.theses.fr/2021TROY0003.
Full textThe aim of this Ph.D. thesis is to study the thermal performance of metal foam and phase change material (PCM) composite by using the experimental and numerical methods, in which metal foam possesses a cubic cell structure and is fabricated by 3D printing technique. Firstly, the effects of contact and heat conditions on heat storage rate of PCM composite are investigated to provide theoretical guidance for the practical application of PCM composite in thermal energy storage (TES) system. Then the metal foam with a cubic cell structure is designed and fabricated by 3D printing. The experimental investigation is carried out to examine the melting evolution of PCM embedded in metal foam. Meanwhile, the pore-scale numerical method is also proposed and used to investigate heat transfer characteristics of PCM composite. It is found from the results that the embedding metal foam can short the total melting time of PCM. Considering the influence of morphology parameters of metal foam, the thermal behavior of metal foam with different porosities and pore densities is numerically studied. The last part of this thesis explores the application of metal foam in PCM based heat sink. The thermal response of heat sinks using PCM composite is obtained by the experimental test, including base temperature, temperature variation, operating time and enhancement ratio of operating time. Also, the effects of the porosity of metal foam and the power level of the heater on the thermal response of heat sink are investigated
Barajas, Leandro G. "Process Control in High-Noise Environments Using A Limited Number Of Measurements." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/7741.
Full textCHANG, YIN CHING, and 殷慶璋. "The Study of the Impact of Computer Forms Printing Industry as Computer Technology Changes." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/73512213783638724683.
Full text中國文化大學
印刷傳播研究所
88
The purpose of this research is to discuss the impact of computer forms printing industry as computer technology changes. The basic frame of this research is from the theory of Martin Dehayes, Hofferand Perkins (1991), and the professor and industry expert modification. The research object is investigated and based on members of Computer Forms Printing Member and Factory Register (1999) which is subsidiary to Taiwan Printing Industry Association. The method of this investigation is universal and general. Here is conclusion: 1.The result of this thesis show that New Technology includes the progress and vast using of printers and environment of Office Automation is getting mature, and the replacement of information product are also big push are affecting factories such as general computer forms ones, computer color forms ones, and exceptional computer forms ones more signally; New Technology includes the depending on less quantity but various type consumption methods, replacement of information product, and increasing demand of professional computer software are affecting the factories such as general computer forms ones, computer color forms ones, and exceptional computer forms ones more signally. 2.Three factors are affecting the computer forms printing industry as this report suggests. The first factor is the New Technology factor. It includes the environment of Office Automation is getting mature and the increasing demand of professional computer software. Furthermore, the electronic commercial and Internet technology, replacement of information product are also big push. The second factor is technology of production of computer forms, which contains the competition of industry, investment of computer printing equipment, automation of production of computer forms, and education of Hi-tech technology. The third factor is the new type of consumption, which is depended on less quantity but various type consumption methods. 3.As shown in this research, the information technology changing, which related to computer forms printing industry, evidently depends on personal opinion. 4.According to the research, the various type of computer forms printing industry products and factories such as general computer forms ones, computer color forms ones, and exceptional computer forms ones are affecting the technology apparently differently.
Robles-Martinez, P., X. Xu, S. J. Trenfield, A. Awad, A. Goyanes, Richard Telford, A. W. Basit, and S. Gaisford. "3D Printing of a Multi-Layered Polypill Containing Six Drugs Using a Novel Stereolithographic Method." 2019. http://hdl.handle.net/10454/17370.
Full textThree-dimensional printing (3DP) has demonstrated great potential for multi-material fabrication because of its capability for printing bespoke and spatially separated material conformations. Such a concept could revolutionise the pharmaceutical industry, enabling the production of personalised, multi-layered drug products on demand. Here, we developed a novel stereolithographic (SLA) 3D printing method that, for the first time, can be used to fabricate multi-layer constructs (polypills) with variable drug content and/or shape. Using this technique, six drugs, including paracetamol, cffeine, naproxen, chloramphenicol, prednisolone and aspirin, were printed with dfferent geometries and material compositions. Drug distribution was visualised using Raman microscopy, which showed that whilst separate layers were successfully printed, several of the drugs diffused across the layers depending on their amorphous or crystalline phase. The printed constructs demonstrated excellent physical properties and the different material inclusions enabled distinct drug release profiles of the six actives within dissolution tests. For the first time, this paper demonstrates the feasibility of SLA printing as an innovative platform for multi-drug therapy production, facilitating a new era of personalised polypills.
Wang, Shang-Tong, and 王上通. "Improving Form-Printing Software Maintenance by Maintenance-Oriented Design." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/85022192903962741134.
Full text國立中興大學
資訊網路多媒體研究所
100
Software maintenance cost has always accounted for a large share of total software cost. Study has shown that optimizing software maintenance should begin at the software planning phrase by evaluating the software maintenance problems. The main goal is to improve software maintainability and to reduce the probability of maintenance requirements. Yet most mathematic researches in the past had focused on managing software maintenance after its occurrence. The tasks associated with software maintenance can be divided into corrective maintenance caused by errors in software construction, or adaptive and comprehensive maintenance needed for software that can yet accommodate future technical requirements. Errors in software construction can be effectively corrected via software engineering; it is the insufficient software adaptability that requires the most maintenance, and there is a lack of research and useable techniques associated with this problem. The purpose of maintenance-oriented design is to reduce the occurrence of software maintenance to optimize the goal of software maintenance engineering. User experiences are analyzed to offset the inability to identify every possible demand by the users. Software maintenance occurrences are reduced and means of resolving the problems are provided based on sample occurrences that have occurred. The common mandatory basic functions are then selected and pre-established in the software system to strengthen software adaptability. Information and software structures are then generically designed so that information processing signs and functions are separately composed. This way it would be easier to maintain software structure, information processing can be generically designed, and users would be allowed to customize the user interface for information processing. Customization can better satisfy user need, and these methods will help reduce the occurrence of software maintenance. This study utilized maintenance-oriented design and tested using generic form-printing software. The result showed that generically designed form-printing software can process the items to be printed without constraints, and would only require software maintenance when information processing ability is sufficient for unknown form formats, as new capability would have to be added to process that information. This type of design can reduce both the probability and cost of software maintenance.
Nascimento, Nuno Alexandre Mota Ferreira Pereira. "Numerical and Experimental Analysis of Polymeric Foams obtained by 3D Printing (Additive Manufacturing)." Master's thesis, 2019. https://hdl.handle.net/10216/122455.
Full textAbd, El Kader Magdy Ezzat. "Application of Hot-Melt Ink Jet Processes for Imaging at Offset Printing Form Cylinder." Doctoral thesis, 2003. https://monarch.qucosa.de/id/qucosa%3A18099.
Full textDer Fortschritt im Bereich von Charakterisierung und Verständnis für Hot-melt Ink Jet Prozesse zur Bebilderung von Offsetdruckform-Zylindern ist ein Ergebnis dieser Forschung. Die Systematik dieser Arbeit basiert auf einem theoretischen Teil, um einen geeigneten Löschprozess auszuwählen. Der Löschprozess hängt von den Eigenschaften des Hot-melt Ink Jet Materials und der genutzten Aluminiumdruckoberfläche ab. Diese werden systematisch im Labormaßstab experimentell untersucht. Der thermische Prozess wurde einerseits durch Benetzbarkeitsprüfungen und anderseites durch Rasterelektronmikroskopaufnahmen bewertet.Der Ultraschallprozess ist ein nasser Löschprozess. Die Untersuchungen wurden in vier Stufen systematisch durchgeführt - Auswahl vom geeigneten Lösungsmitteln - Einflüsse von ausgewählten Lösungsmitteln auf nicht beschichtete und beschichtete Aluminium platten - Evaluation eines Ultraschalllöschprozesses - Validation eines Löschprozesses; zur Bewertung des Löschprozesses wurden mehrere Druckplattenproben bebildert und gelöscht Die Ergebnisse wurden durch UV/Vis Spektrometer, Kontaktwinkel, Profiliometrie und Visuelle Mikroskopie getestet.
Oliveira, Rúben Miguel Cardoso Gomes. "Impressão 3D de polímeros: Influência do fator de forma na avaliação das propriedades mecânicas." Master's thesis, 2019. http://hdl.handle.net/10316/98256.
Full textA impressão 3D de polímeros passou da prototipagem rápida para o fabrico de componentes/peças com aplicações em áreas distintas que vão desde a saúde até à aeronáutica. A possibilidade de efetuar peças com baixo custo, personalizadas e com menor impacto ambiental estão entre os fatores que impulsionaram a popularização deste método de processamento.No entanto, vários são os fatores de processamento durante a impressão 3D que podem influenciar as propriedades mecânicas das peças produzidas. De entre eles, o fator forma, que se refere ao conjunto dos limites exteriores de um corpo que lhe conferem determinada configuração, nunca foi estudado, pelo menos de acordo com a bibliografia consultada.Assim, o objetivo deste trabalho é o de avaliar o fator forma nas propriedades mecânicas de poli( -caprolactona) (PCL) após impressão 3D. Para o efeito foram produzidos provetes com geometria paralelepipédica e tubular, por impressão longitudinal e em altura (transversal). Devida à grande utilização deste polímero em diversos dispositivos médicos, foi também avaliada a influência do envelhecimento em soro fisiológico nas mesmas propriedades mecânicas.Este estudo permitiu concluir que as melhores propriedades mecânicas são obtidas para a geometria de paralelepípedo com uma impressão longitudinal e que o envelhecimento em soro fisiológico influência de modo negativo todas as propriedades avaliadas ao longo deste estudo .
3D printing of polymers has evolved from rapid prototyping to component/part manufacturing with applications in distinct areas ranging from health to aeronautics. The possibility of making low-cost, customized parts with less environmental impact are among the factors that have led to the exponential growth of this processing method.However, there are several processing factors during 3D printing that can influence the mechanical properties of the parts produced. Among them, the form factor, which refers to the set of outer limits of a body that give it a certain configuration, has never been studied, at least according to the bibliography consulted.Thus, the objective of this work is to evaluate the shape factor in the mechanical properties of poly (-caprolactone) (PCL) after 3D printing. For this purpose, specimens with parallelepiped and tubular geometry were produced by longitudinal and height (transversal) impressions. Due to the great use of this polymer in several medical devices, the influence of aging in physiological saline solution on the same mechanical properties was also evaluated.This study allowed to conclude that the best mechanical properties are obtained for parallelepiped geometry with a longitudinal impression and that aging in physiological saline negatively influences all the properties evaluated throughout this study .
Dias, Adriana Maria Lopes. "Impressão FFF de polímeros de memória de forma." Master's thesis, 2020. http://hdl.handle.net/1822/70524.
Full textOs shape-memory polymers (SMP), ou polímeros de memória de forma, são uma classe de materiais inteligentes, mecanicamente ativos, capazes de alterar a sua forma em resposta a um estímulo, como por exemplo, temperatura, radiação, impulsos elétricos, etc. Nesta dissertação de mestrado pretendeu-se avaliar as características de um material com memória de forma, impresso pela técnica de Fabricação por Filamento Fundido (FFF). Para o efeito, foi necessário definir e validar uma metodologia adequada à caracterização do mesmo, tendo como principais objetivos analisar a influência da temperatura de recuperação e influência da espessura da amostra na força que o material promove durante a fase de recuperação. Numa fase inicial, foi extrudido filamento do material SMP com diâmetro calibrado para o processo de impressão 3D. Foi também necessário selecionar a geometria da amostra para o ensaio e proceder à identificação da janela operatória de impressão deste material. Imprimiram-se várias peças com diferentes espessuras (0.5, 1 e 2mm), para analisar a sua influência sobre a força de recuperação e caraterizaram-se as amostras de acordo com a metodologia definida usando o equipamento de análise mecânica dinâmica (DMA), que analisou a recuperação restringida do material. Para uma mesma espessura, 1 mm, obteve-se, para a temperatura mínima de 50 °C, a força de recuperação de 104 mN e, para a temperatura máxima de 70 °C, obteve-se a força de recuperação de 494 mN; uma variação de 20 °C na temperatura originou um aumento de 390mN (375 %) na referida força. Para uma mesma temperatura, 70 °C, obteve-se, para a espessura mínima de 0.5mm, a força de recuperação de 325 mN e, para a espessura máxima de 2mm, obteve-se a força de recuperação de 932 mN; um aumento de 1.5 mm na espessura provocou um aumento de 607 mN (187 %) na força de recuperação. Concluiu-se assim que, quanto mais elevada for a temperatura de recuperação, maior é o valor da força que o material promove quando recupera a forma permanente e que, quanto maior a espessura do provete, maior o valor desta força.
Shape memory polymers (SMP) are a class of mechanically active smart materials, capable of altering their shape in response to a stimulus as, temperature, radiation, electrical impulses, etc. In this master's dissertation, it was intended to evaluate the shape memory characteristics of a material, via samples printed by the Fused Filament Fabrication (FFF) technique. For this purpose, it was necessary to define and to validate an appropriate methodology, with the main objective of analyzing the influence of the recovery temperature and of the thicknesses of the samples on the force released during the recovery stage. In an initial phase, a calibrated diameter SMP material filament for the 3D printing process was extruded. It was also necessary to select the geometry of the test specimen, and proceed to the identification of the operating window for printing this material. Several samples were printed with different thicknesses (0.5, 1 e 2 mm), in order to also analyze their influence on the recovery force. These components were then characterized according to a methodology using the dynamic mechanical analysis equipment (DMA), which analyzed the constrained recovery of the material. For the 1 mm samples thickness, and for the minimum recovery temperature of 50 °C, a recovery force of 104 mN was obtained, while for the maximum temperature of 70 °C this force was 494 mN. Therefore, a 20 °C variation in temperature caused an increase of 390 mN (375 %) in that force. For the 70 °C recovery temperature, and the maximum thickness of 2 mm, a recovery force of 932 mN was obtained, i.e.an increase of 1.5 mm in thickness caused an increase of 607 mN (187 %) in the recovery force. It was concluded that, the higher the recovery temperature, the higher the value of the recovery force and that the higher the thickness of the sample, the higher the value of this force.
Abd-el-Kader, Magdy Ezzat [Verfasser]. "Application of hot melt ink jet processes for imaging at offset printing form cylinder / vorgelegt von Magdy Ezzat Abd El Kader." 2004. http://d-nb.info/970645775/34.
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