[ES] La fabricación aditiva, también llamada impresión 3D, ha tenido un gran impacto en la industria. La capacidad de fabricar modelos complejos y personalizados a bajo coste se adapta muy bien para algunas aplicaciones, sustituyendo procesos de fabricación tradicional y ofreciendo nuevas oportunidades. En medicina, la fabricación personalizada de modelos complejos ha encontrado muchas aplicaciones, desde réplicas de patologías para la educación hasta implantes hechos a medida y remplazo de órganos. De todas las posibilidades de esta tecnología en medicina, la fabricación de modelos anatómicos a partir de imágenes médicas ofrece un excelente balance entre facilidad de implementación y beneficio, esto la hace una aplicación perfecta para ser usada ampliamente en los hospitales. La fabricación aditiva de modelos anatómicos es un campo que ha suscitado considerable entusiasmo en los últimos años. La comunidad médica ve esta herramienta como el siguiente paso generacional en la visualización clínica, ofreciendo grandes beneficios para los pacientes y el sistema de salud. Debido al gran interés, hay muchos investigadores que han evaluado el impacto de esta tecnología en la práctica médica, midiendo los beneficios médicos que puedan tener estos modelos anatómicos. En general, los resultados muestran que hay reducción de tiempo de quirófano, menor morbilidad y mortalidad al igual que menor estrés y denuncias por parte de pacientes. A pesar de estos resultados prometedores, no hay muchos estudios realizados sobre cuál debe ser el proceso para garantizar la reproducibilidad y seguridad de estos modelos, un tema que es de gran importancia para poder cumplir con las regulaciones actuales, que exigen protocolos de fabricación y sistemas de calidad para este proceso. Debemos observar que, aunque el proceso para obtener modelos anatómicos es más fácil que otras aplicaciones de esta tecnología, no es un proceso trivial. Es un trabajo complejo con múltiples pasos que Involucra a varios especialistas para su correcta realización. Actualmente el hospital es el entorno ideal para poder fabricar estos modelos, permite un mayor control del proceso, facilita la colaboración multidisciplinar necesaria y reduce considerablemente los requisitos legales que rigen los dispositivos médicos. El objetivo de esta investigación es desarrollar un protocolo detallado y optimizado que cumpla con los requisitos técnicos, médicos y legales para poder implementar esta tecnología emergente de forma segura y eficiente en centros de salud. Para alcanzar este objetivo, las metodologías observadas fueron la revisión por literatura, la investigación doctrinal legal y la investigación acción empleada en los diferentes casos estudiados. Los casos se han elegido buscando la mayor diversidad posible bajo el criterio de conveniencia en el horizonte temporal contemplado, dada la diversidad compleja del estudio realizado. Gracias a la colaboración con varias instituciones médicas y de educación, este protocolo se pudo implementar en diversos contextos, mejorándolo progresivamente al ponerlo a prueba con casos reales, mediante el trabajo continuo con los expertos. El resultado es un protocolo que incluye varios años de experiencia y que ha sido aplicado en un amplio rango de especialidades. Este protocolo es relativamente sencillo de seguir y cumple con los principales requisitos para ser implementado en hospitales. / [CA] La fabricació additiva, també anomenada impressió 3D, ha tingut un gran impacte en la indústria. La capacitat de fabricar models complexos i personalitzats a baix cost s' adapta molt bé per a algunes aplicacions, substituint processos de fabricació tradicional i oferint noves oportunitats. En medicina, la fabricació personalitzada de models complexos ha trobat moltes aplicacions, des de rèpliques de patologies per a l'educació fins a implants fets a mida i òrgans. De totes les possibilitats d'aquesta tecnologia en medicina, la fabricació de models anatòmics a partir d'imatges mèdiques ofereix un excel·lent balanç entre facilitat d'implementació i benefici, això la fa una aplicació perfecta per ser usada àmpliament als hospitals. La fabricació additiva de models anatòmics és un camp que ha suscitat considerable entusiasme en els últims anys. La comunitat mèdica veu aquesta eina com el següent pas generacional en la visualització clínica, oferint grans beneficis per als pacients i el sistema de salut. A causa del gran interès, hi ha molts investigadors que han avaluat l'impacte d'aquesta tecnologia en la pràctica mèdica, mesurant els beneficis mèdics que puguen tenir aquests models anatòmics. En general, els resultats mostren que hi ha reducció de temps de quiròfan, menor morbiditat i mortalitat igual que menor estrès i denúncies per part de pacients. Malgrat aquests resultats prometedors, no hi ha molts estudis realitzats sobre quin ha de ser el procés per garantir la reproduïbilitat i seguretat d' aquests models, un tema que és de gran importància per poder complir amb les regulacions actuals, que exigeixen protocols de fabricació i sistemes de qualitat per a aquest procés. Hem d'observar que, tot i que el procés per obtenir models anatòmics és més fàcil que altres aplicacions d'aquesta tecnologia, no és un procés trivial. És un treball complex amb múltiples passos que Involucra diversos especialistes per a la seva correcta realització. Actualment l'hospital és l'entorn ideal per poder fabricar aquests models, permet un major control del procés, facilita la col·laboració multidisciplinària necessària i redueix considerablement els requisits legals que regeixen els dispositius mèdics. L'objectiu d'aquesta investigació és desenvolupar un protocol detallat i optimitzat que compleix amb els requisits tècnics, mèdics i legals per poder implementar aquesta tecnologia emergent de forma segura i eficient en centres de salut. Per assolir aquest objectiu, les metodologies observades van ser la revisió per literatura, la investigació doctrinal legal i la investigació acció emprada en els diferents casos estudiats. Els casos s' han triat buscant la major diversitat possible sota el criteri de conveniència en l' horitzó temporal contemplat, atesa la diversitat complexa de l' estudi realitzat. Gràcies a la col·laboració amb diverses institucions mèdiques i d'educació, aquest protocol es va poder implementar en diversos contextos, millorant-lo progressivament en posar-lo a prova amb casos reals, mitjançant el treball continu amb els experts. El resultat és un protocol que inclou diversos anys d' experiència i que ha estat aplicat en un ampli rang d' especialitats. Aquest protocol és relativament senzill de seguir i compleix amb els principals requisits per ser implementat en hospitals. / [EN] Additive manufacturing, also called 3D printing, has had a huge impact on the industry. The ability to manufacture complex and customized models at a low cost is well suited for some applications, replacing traditional manufacturing processes and offering new opportunities. In medicine, the custom manufacture of complex models has found many applications, from replicas of pathologies for education to custom-made implants and organ replacement. Of all the possibilities of this technology in medicine, the manufacture of anatomical models from medical images offers an excellent balance between ease of implementation and benefit, this makes it a perfect application to be widely used in hospitals. Additive manufacturing of anatomical models is a field that has attracted considerable enthusiasm in recent years. The medical community sees this tool as the next generational step in clinical visualization, offering great benefits for patients and the healthcare system. Due to the great interest, there are many researchers who have evaluated the impact of this technology on medical practice, measuring the medical benefits that these anatomical models may have. In general, the results show that there is a reduction in operating room time, lower morbidity and mortality as well as less stress and complaints from patients. Despite these promising results, there are not many studies conducted on what the process should be to guarantee the reproducibility and safety of these models, an issue that is of great importance to be able to comply with current regulations, which require manufacturing protocols and quality systems for this process. We should note that although the process for obtaining anatomical models is easier than other applications of this technology, it is not a trivial process. It is a complex work with multiple steps that involves several specialists for its correct realization. Currently the hospital is the ideal environment to be able to manufacture these models, it allows greater control of the process, facilitates the necessary multidisciplinary collaboration, and considerably reduces the legal requirements that govern medical devices. The objective of this research is to develop a detailed and optimized protocol that meets the technical, medical, and legal requirements to implement this technology in hospitals. To achieve this objective, the methodologies observed consisted of literature review, legal doctrinal research and action research used in the multiple cases studied. The cases have been selected seeking the greatest possible diversity under the criterion of convenience in the time horizon contemplated, given the complex diversity of the study carried out. Thanks to the collaboration with several medical and educational institutions, this protocol could be implemented in various contexts, progressively improving it by testing it with real cases, through continuous work with experts. The result is a protocol that includes several years of experience and has been applied in a wide range of specialties. It is relatively simple to follow and complies with most requirements to be implemented in hospitals. / De Rossi Estrada, M. (2022). Investigación para el desarrollo de un protocolo para fabricación aditiva de modelos anatómicos en centros de salud [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/183303 / TESIS

This project was a test of concept for an external heating system for Big Area Additive Manufacturing (BAAM) Fused Deposition Modeling (FDM) 3D printers. To goal of the heating system was to prevent or mitigate delamination and warping in BAAM FDM prints by propelling warm air onto printed layers while not interfering with prior functions of the 3D printer.

Plastics contribute 2 GTons to the global carbon footprint, today, several countries have set targets to achieve carbon neutrality. Plastics, being a major contributor to global carbon footprint, would need to be reduced significantly from our daily life to achieve that or a way needs to be devised to recycle them. A big bottleneck in this process is to reduce the consumption of thermosetting plastics or to reduce the emissions associated with plastic and move towards economical and environmentally safe plastics having a longer lifespan and efficient recyclability. Fused filament fabrication (FFF) is the most commonly used 3D printed technology available today. Its applications range from production of prototypes to hollow shafts, and fully functional commercial components. This technology is revolutionary in a sense that it offers advantages such as cheaper raw materials, high degree of customizability, production in smaller batches at lower costs, decrease in material wastage, rapid prototyping, and complex geometry. A number of thermoplastic polymers can be used with FFF technology to produce parts, in addition research is on going to print materials not commonly used for FFF process. Polyoxymethylene (POM) could be a viable option for utilization as FFF basestock for the production of tribologically functional components. POM is an engineering thermoplastic that offers high resistance to wear, low friction, excellent impact resistance, and good chemical resistance. These properties render it suitable for production of gear wheels and low load bearings. It is currently processed using traditional manufacturing methods such as injection and compression moulding, while its printability has received very little attention in the openly available literature. An attempt has been made in this thesis to fill up this research gap by providing insight into POM filament quality, and the thermal, mechanical, and tribological behaviour of POM printed parts. The influence of overfill and layer height on the bulk properties of the printed samples, its play with counterface surface roughness and applied load has also been investigated.

In this thesis, the incorporation of drug loaded mesoporous magnesium carbonate as an excipient for the additive manufacturing of oral tablets by fused deposition modeling was investigated. Cinnarizine, a BCS class II drug, was loaded into the pores of the mesoporous material via a soaking method, corresponding to a drug loading of 8.68 wt%. DSC measurements on the loaded material suggested that the drug was partially crystallized after incorporation, meanwhile the XRD diffractogram implied that the drug was in a state lacking long range order. The drug loaded material was combined with two pharmaceutical polymers, Aquasolve LG and Klucel ELF, and extruded into filaments with a single screw extruder. Filaments of Klucel ELF and drug loaded Upsalite (30:70 wt% ratio) were successfully implemented for the printing oral tablets, in contrast to the Aquasolve LG based filaments which were difficult to print due to thickness variations and non-uniform material distributions. The drug content obtained by TGA suggested drug loadings of 7.71 wt% and 2.23 wt% in the drug loaded Upsalite and tablets respectively. Dissolution studies using an USP II apparatus showed a slower API-release from the tablets in comparison to the crystalline drug, most probably due to slow diffusion of drug species through the polymeric matrix. For future studies, pharmaceutical polymers with higher aqueous solubility should be investigated in order to thoroughly examine the potential of utilizing the immediate release property of Upsalite.

An obstacle to the wide spread use of additive manufacturing (AM) is the difficulty in estimating the effects of process parameters on the mechanical properties of the manufactured part. The complex relationship between the geometry, parameters and mechanical properties makes it impractical to derive an analytical relationship and calls for the use of a numerical model. An approach to formulate a numerical model in developed in this thesis. The AM technique focused in this thesis is fused filament fabrication (FFF). A numerical model is developed by recreating FFF build process in a simulation environment. Machine instructions generated by a slicer to build a part is used to create a numerical model. The model acts as a basis to determine the effects of process parameters on the stiffness and the strength of a part. Determining the stiffness of the part is done by calculating the response of the model to a uniformly distributed load. The strength of the part depends on it's thermal history. The developed numerical model serves as a basis to implement models describing the relation between thermal history and strength. The developed model is suited to optimize FFF parameters as it encompass effects of all FFF parameters. A genetic algorithm is used to optimize the FFF parameters for minimum weight with a minimum stiffness constraint. / Ett hinder för att additiv tillverkning (AT), eller ”3D-printing”, ska få ett bredare genomslag är svårigheten att uppskatta effekterna av processparametrar på den tillverkade produktens mekaniska prestanda. Det komplexa förhållandet mellan geometri och processparametrar gör det opraktiskt och komplicerat att härleda analytiska uttryck för att förutsäga de mekaniska egenskaperna. Alternativet är att istället använda numeriska modeller. Huvudsyftet med denna avhandling har därför varit att utveckla en numerisk modell som kan användas för att förutsäga de mekaniska egenskaperna för detaljer tillverkade genom AT. AT-tekniken som avses är inriktad på Fused Filament Fabrication (FFF). En numerisk modell har utvecklats genom att återskapa FFF-byggprocessen i en simuleringsmiljö. Instruktioner (skriven i GCode) som används för att bygga en detalj genom FFF har här översatts till en numerisk FE-modell. Modellen används sen för att bestämma effekterna av processparametrar på styvheten och styrkan hos den tillverkade detaljen. I detta arbete har strukturstyvheten hos olika detaljer beräknats genom att utvärdera modellens svar för jämnt fördelade belastningsfall. Styrkan, vilket är starkt beroende på den tillverkade detaljens termiska historia, har inte utvärderats. Den utvecklade numeriska modellen kan dock fungera som underlag för implementering av modeller som beskriver relationen mellan termisk historia och styrka. Den utvecklade modellen är anpassad för optimering av FFF-parametrar då den omfattar effekterna av alla FFF-parametrar. En genetisk algoritm har använts i detta arbete för att optimera parametrarna med avseende på vikt för en given strukturstyvhet.

Purpose: This paper will present insight to the methodology and results of the experimental characterization of Acrylonitrile Butadiene Styrene (ABS) using Fused Deposition Modeling (FDM). The work in this research explored the effects of print orientation, surface treatment, and ultraviolet (UV) light degradation with the utilization of Digital Image Correlation (DIC) on ABS tensile specimens. Design/methodology: ABS specimens were printed at three build orientations (flat (0 degrees), 45 degrees, and up-right (90 degrees)). Each of these specimens were treated with three different surface treatments including a control (acrylic paint, Cyanoacrylate, and Diglycidyl Bisphenol A) followed by exposure to UV light to the respective batches. This experiment design will provide tensile direction properties with the effect of thermoset coatings and UV degradation. Dogbone FDM specimens based on ASTM standard D638 type IV were printed on a Stratasys Dimension SST (Soluble Support Technology) 1200es 3D Printer and loaded into a MTS Landmark Servohydraulic Test Systems. Analysis was preformed on the fracture section of the tensile specimens utilized DIC and comparing Ultimate Tensile Strength (UTS) and Ultimate Fracture Strength (UFS). Findings: From the results UV light did not play a large factor in the strength of the specimens. The print orientation showed the largest anisotropic behavior where some specimens experienced as much as a 54% difference in ultimate tensile strength. Thermoset coated specimens experienced a maximum of 2% increase in strength for the Cyanoacrylate and Diglycidyl Bisphenol A specimens where the acrylic paint and natural did not. Several findings were of value when looking at the stress strain plots. Originality/value: This paper provides knowledge to the limited work on print build orientation, thermoset coatings and, UV light on ABS specimens. Very little to no work has been done on these three properties. This paper can serve as the foundation of future work on external applications on ABS plastics.

No description available.

The relatively new and still growing field of 3D-printing has opened up the possibilities to manufacture patient-specific medical devices with high geometrical accuracy in a precise and quick manner. Additionally, biocompatible materials are a demand for all medical applications while biodegradability is of importance when developing scaffolds for tissue growth for instance. With respect to this, this project consisted of developing biocompatible and bioresorbable polymer blend and composite filaments, for fused deposition modeling (FDM) printing. Poly(lactic acid) (PLA) and polycaprolactone (PCL) were used as supporting polymer matrix while hydroxyapatite (HA), a calcium phosphate with similar chemical composition to the mineral phase of human bone, was added to the composites to enhance the biological activity. PLA and PCL content was varied between 90–70 wt% and 10-30 wt%, respectively, while the HA content was 15 wt% in all composites. All materials were characterized in terms of mechanical properties, thermal stability, chemical composition and morphology. An accelerated degradation study of the materials was also executed in order to investigate the degradation behavior as well as the impact of the degradation on the above mentioned properties. The results showed that all processed materials exhibited higher mechanical properties compared to the human trabecular bone, even after degradation with a mass loss of around 30% for the polymer blends and 60% for the composites. It was also apparent that the mineral accelerated the polymer degradation significantly, which can be advantageous for injuries with faster healing time, requiring only support for a shorter time period.

Submitted by Marta Toyoda (1144061@mackenzie.br) on 2018-05-14T18:21:27Z No. of bitstreams: 2 André da Silva Siqueira.pdf: 3776282 bytes, checksum: 6603b366db594cfde0276b33c03a1968 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Paola Damato (repositorio@mackenzie.br) on 2018-05-21T13:34:35Z (GMT) No. of bitstreams: 2 André da Silva Siqueira.pdf: 3776282 bytes, checksum: 6603b366db594cfde0276b33c03a1968 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-05-21T13:34:35Z (GMT). No. of bitstreams: 2 André da Silva Siqueira.pdf: 3776282 bytes, checksum: 6603b366db594cfde0276b33c03a1968 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present work aims to obtain and characterize a composite filament based on poly (lactic acid) (PLA), hydroxyapatite (HA) and graphene oxide, to process it by fused deposition modeling (FDM), and then make scaffolds for bone tissue growth and order to evaluate the properties of the obtained structure. To achieve these goals composite of PLA/HA, PLA/GO and PLA / HA / GO with concentrations of 0.05 wt %, 0.1 wt % and 0.3 wt % GO and 30 wt % HA were obtained by melt state blending and subsequently processed by FDM. The graphite oxide was obtained by modified Hummers method and characterized by X-ray diffraction (XRD), thermogravimetric analysis and Raman spectroscopy. The PLA and composites were characterized by molar mass measurements, infrared and Raman spectroscopy, tensile strength tests, contact angle measurements (surface energy), differential scanning calorimetry (DSC) and rheological tests. The insertion of GO into PLA and PLA/HA composites led to improvements in the mechanical properties (tensile) and also modified significantly the surface properties of the materials and the composition with 0.05 wt % of GO has shown the better results in both characteristics. These improvements occurred due to the strong interaction of the GO sheets with the PLA matrix that indicates the process of obtaining the composites via the melting state was correctly conducted. All PLA / HA / GO compositions presented rheological characteristics compatible with of scaffolds production process via FDM. The insertion of the GO into the PLA matrix and the PLA / HA composite has been shown to be extremely promising, and possibly to increase the variety of PLA / HA based biomaterials application. / O presente trabalho visa obter e caracterizar um filamento compósito baseado em poli(ácido lático) (PLA), hidroxiapatita (HA) e óxido de grafeno, processá-lo por Fused deposition modeling (FDM), fabricar scaffolds para crescimento de tecido ósseo. Para alcançar esses objetivos fcompósitos de PLA/HA, PLA/GO e PLA/HA/GO com concentrações de 0,05%, 0,1% e 0,3% de GO e 30% de HA (em massa) foram preparados por meio de mistura no estado fundido e posteriormente processados por FDM. Comprovou-se a obtenção do óxido de grafite por técnicas de difração de raios-X (DRX), análise termogravimétrica e espectroscopia Raman. O PLA e os compósitos foram caracterizados por medidas de massa molar da matriz polimérica, espectroscopia no infravermelho e Raman, ensaios mecânicos de tração, medidas de ângulos de contato (energia de superfície), calorimetria exploratória diferencial (DSC) e ensaios reológicos. A inserção do GO no PLA e no compósito PLA/HA conduziu a melhorias das propriedades mecânicas (tração) dos materiais e também modificou significativamente as propriedades de superfície dos materiais estudados, sendo a concentração de 0,05% em massa a que apresentou melhor desempenho em ambas as características. Essas melhorias aconteceram devido à forte interação das folhas de GO com a matriz de PLA, o que indica que o processo de obtenção dos compósitos via estado fundido foi corretamente conduzido. Todas as composições PLA/HA/GO apresentaram características reológicas compatíveis com o processo de produção dos scaffolds via FDM. A inserção do GO na matriz de PLA e no compósito PLA/HA demonstrou-se ser extremamente promissora, e possivelmente aumentarão a variedade de aplicações dos biomateriais baseados em PLA/HA.

Additive Manufacturing (AM) is on the verge of causing a downfall to conventional manufacturing with its huge potential in part manufacture. With an increase in demand for customized product, on-demand production and sustainable manufacturing, AM is gaining a great deal of attention from different industries in recent years. AM is redefining product design by revolutionizing how products are made. AM is extensively utilized in automotive, aerospace, medical and dental applications for its ability to produce intricate and lightweight structures. Despite their popularity, AM has not fully replaced traditional methods with one of the many reasons being inferior surface quality. Surface texture plays a crucial role in the functionality of a component and can cause serious problems to the manufactured parts if left untreated. Therefore, it is necessary to fully understand the surface behavior concerning the factors affecting it to establish control over the surface quality. The challenge with AM is that it generates surfaces that are different compared to conventional manufacturing techniques and varies with respect to different materials, geometries and process parameters. Therefore, AM surfaces often require novel characterization approaches to fully explain the manufacturing process. Most of the previously published work has been broadly based on two-dimensional parametric measurements. Some researchers have already addressed the AM surfaces with areal surface texture parameters but mostly used average parameters for characterization which is still distant from a full surface and functional interpretation. There has been a continual effort in improving the characterization of AM surfaces using different methods and one such effort is presented in this thesis. The primary focus of this thesis is to get a better understanding of AM surfaces to facilitate process control and optimization. For this purpose, the surface texture of Fused Deposition Modeling (FDM) and Laser-based Powder Bed Fusion of Metals (PBF-LB/M) have been characterized using various tools such as Power Spectral Density (PSD), Scale-sensitive fractal analysis based on area-scale relations, feature-based characterization and quantitative characterization by both profile and areal surface texture parameters. A methodology was developed using a Linear multiple regression and a combination of the above-mentioned characterization techniques to identify the most significant parameters for discriminating different surfaces and also to understand the manufacturing process. The results suggest that the developed approaches can be used as a guideline for AM users who are looking to optimize the process for gaining better surface quality and component functionality, as it works effectively in finding the significant parameters representing the unique signatures of the manufacturing process. Future work involves improving the accuracy of the results by implementing improved statistical models and testing other characterization methods to enhance the quality and function of the parts produced by the AM process.