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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Elaboração de protocolo de ensaios mecânicos para avaliação da performance do material PLA através da manufatura aditiva por meio do processo FDM / Preparation of mechanical test protocol for evaluation of pla material performance through additive manufacturing by fdm process

Branco, Rodolfo Ramos Castelo 19 December 2016 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2018-05-24T14:11:32Z No. of bitstreams: 1 PDF - Rodolfo Ramos Castelo Branco.pdf: 33386528 bytes, checksum: d16a1c9b6b747be04f2968cf6f66ceaf (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2018-06-05T11:33:25Z (GMT) No. of bitstreams: 1 PDF - Rodolfo Ramos Castelo Branco.pdf: 33386528 bytes, checksum: d16a1c9b6b747be04f2968cf6f66ceaf (MD5) / Made available in DSpace on 2018-06-05T11:33:25Z (GMT). No. of bitstreams: 1 PDF - Rodolfo Ramos Castelo Branco.pdf: 33386528 bytes, checksum: d16a1c9b6b747be04f2968cf6f66ceaf (MD5) Previous issue date: 2016-12-19 / Technological innovation has been a constant in several areas in the contemporary world, emphasizing in the areas of engineering and health. In this scenario, there is the Additive Manufacturing (MA), which consists of a manufacturing process using the addition of material in successive flat layers, in which it is possible to generate 3D physical parts obtained directly from CAD (Computer Aided Design). The MA is divided into several processes, in this study it will be highlighted by Fusion and Deposition Modeling (FDM) of the solids class, which uses solid polymer coils, especially Poly lactic acid (PLA). This technology of manufacturing process has been gaining more and more prominence in the technological scenario, with which it is possible to affirm that the Additive Manufacturing is on a scale of growth, being considered by many scholars as the new industrial revolution, which obviously opens space for New research in the area, thus necessitating the consolidation of processes, machinery and materials. In this context of recognition of the participation that the Additive Manufacturing process has been achieving, this study aimed to elaborate mechanical testing protocols for the evaluation of PLA material performance through the MA from the FDM process. The applied methodology was based on studying the parameters of construction of the pieces in FDM (structure, raster, deposition rate, temperature, loops, orientation of the raster angle, position orientation of the pieces, among others), to perform the mechanical tests of the Type and analyze the results obtained through strain-strain graphs (maximum tensions, rupture and modulus of elasticity). The result obtained evidenced little difference between the deposition rates (20%, 50% and 100%) regarding the construction time. Regarding the mechanical properties, the pieces with 100% fill characteristics in their internal structure presented better tensions. It was also observed the influence of the position of construction of the specimens in the printing tray, changing its mechanical characteristics. / A inovação tecnológica tem sido uma constante em diversas áreas no mundo contemporâneo, destacando-se nas áreas de engenharia e saúde. Neste cenário, encontra-se a Manufatura Aditiva (MA), que consiste em um processo de fabricação utilizando a adição de material em camadas planas sucessivas, no qual é possível gerar peças físicas em 3D, obtidas diretamente de arquivos de modelagem CAD (Computer Aided Design). A MA divide-se em vários processos, neste estudo será destacado por Modelagem de fusão e deposição (FDM) da classe dos sólidos, o qual utiliza bobinas de polímeros sólidos, especialmente o Poli ácido láctico (PLA). Esta tecnologia de processo de fabricação vem ganhando cada vez mais destaque no cenário tecnológico, com isso é possível afirmar que a Manufatura aditiva se encontra em uma escala de crescimento, sendo considerada por muitos estudiosos como a nova revolução industrial, o que obviamente abre espaço para novas pesquisas na área, havendo assim a necessidade da consolidação dos processos, máquinas e materiais. Neste contexto de reconhecimento da participação que o processo de Manufatura Aditiva vem alcançando, este estudo visou elaborar protocolos de ensaios mecânicos para avaliação de performance do material PLA através da MA a partir do processo FDM. A metodologia aplicada baseou-se em estudar os parâmetros de construção das peças em FDM (estrutura, raster, taxa de deposição, temperatura, loops, orientação do ângulo raster, orientação da posição das peças, dentre outros), em realizar os ensaios mecânicos do tipo tração e analisar os resultados obtidos através dos gráficos de tensão-deformação (tensões máxima, ruptura e modulo de elasticidade). O resultado obtido evidenciou pouca diferença entre as taxas de deposição (20%, 50% e 100%) no tocante ao tempo de construção. Em relação as propriedades mecânicas, as peças de características 100% de preenchimento em sua estrutura interna apresentaram melhores tensões. Observou-se também, a influência da posição de construção dos corpos de prova na bandeja de impressão, alterando suas características mecânicas.
32

Otimização estrutural de protótipos fabricados pela tecnologia FDM utilizando o método dos elementos finitos / Structural optimization of FDM prototypes based on finite element analysis.

Wagner José de Almeida 21 September 2007 (has links)
Este trabalho tem como objetivo principal a otimização dos protótipos fabricados pelo processo FDM (Fused Deposition Modeling) em procedimento baseado na análise do comportamento estrutural dos protótipos variando as estratégias de preenchimento das camadas. Para atingir tal objetivo, corpos de prova com diferentes orientações de preenchimento foram ensaiados experimentalmente e os resultados foram verificados em análise estrutural por elementos finitos. Foram verificados o caráter ortotrópico do material do protótipo e a validade do uso da Teoria Clássica dos Laminados na simulação de seu comportamento. Os conceitos e metodologia de análise foram validados em estudos de casos, mostrando a viabilidade de sua aplicação na obtenção de protótipos funcionais / The objective of this work is to develop an optimization procedure for FDM prototypes. This procedure is based on the structural analysis of the prototypes within different slice filling paths. In order to reach this objective, experimental tests with different filling trajectories are conducted and the results are used in structural analysis by finite element method. The orthotropic behavior of the prototype material and the use of the Classical Laminate Theory in the numerical simulation were validated. The results were applied in different case studies, showing the viability of its application in the design of functional prototypes.
33

Využití 3D tisku v TZB / Using 3D printing in HVAC

Malovaný, Ondřej January 2019 (has links)
In the experimental part of this thesis there is an assessment of pressure bearing capacity of cylindrical nozzles printed using a 3D printer. In the theoretical part of this diploma thesis there are outlined the types of additive technologies focusing on the development of FDM printers, open designs and RepRap project. Descripti-on of the production process of 3D printing and application of additive technolo-gies in the field of HVAC. In the project part, the design of the forced ventilation of the Sports Hall is solved. The object is assessed in terms of heat losses and profits for priority rooms of functional units. Heat load coverage is carried out by air-conditioning equipment. In addition, a project is drawn up which contains all the text and drawings, including technical specifications and regulatory schemes.
34

Návrh 3D tiskárny typu delta pi s temperovanou podložkou s využitím systémů CAE / Design of delta pi 3D printer with tempered bed using CAE systems

Koudela, Ondřej January 2015 (has links)
This master's thesis deals with 3D printing using non-commercial 3D RepRap type printers. This work briefly describes development trends of non-commercial RepRap printers, theory of FDM print with analysis and comparison of materials, which are used in printing and the issue of the finite volume method and theory of heat diffusion. The practical part based on simulations from SolidWorks Flow Simulation discussed two basic methods of heating hot bed, then the temperature profile of hot end and the heat flow in full assembly of the printer. Outcome of this work is design an optimized model and the physical assembly of 3D printer delta pi type.
35

Návrh a zefektivnění parametrů FDM tisku / Design and efficiency of FDM printing parameters

Sysel, Karel January 2012 (has links)
The essence of the work is to test the possibilities specific type of simple 3D printing device, which has recently been getting more and more into the awareness of professionals and the general public. First, the work is focused on presentation 3D printing technology and current professional equipment, in the second part are experimentally evaluated possibilities of of a simple kind of 3D printers followed by assessment of the applicability of the device in engineering practice.
36

FrankZlicer : Direct slicing using arcs

Franzén, Johan January 2019 (has links)
3D printing a CAD modelnormally requires conversion into a polygon mesh, usually an STL-file, in orderto be able to load the model in the slicer. This conversion destroys roundsurfaces and replaces them with flat surfaces. Slicing a polygon mesh resultsin one or more polygons, consisting of a number of straight lines. This canaffect both dimensional accuracy and surface smoothness. Modern 3D-printerscan, in addition to straight lines, handle arcs. However, today’s commonslicers can not generate arcs as the input does not contain any curvedfeatures. This project aims at finding an alternative solution. By directslicing of CAD models the slices can contain arcs, and the slicer can producearc commands for the 3D-printer. During this project a prototype slicer isconstructed as a proof of concept. The prototype handles STEP-files as inputand creates both linear and circular movement for the 3D-printer. The resultsshow that both the intermediate files (STEP/STL) and the resulting G-code filescan get smaller, yet preserving the original shape, by using this method. Theproposed solution has a positive effect on the 3D-printing workflow as well, asthe intermediate files can be imported back into the CAD system. The projectconcludes that there is possibly a bright future for direct slicing, but thereare more problems to solve before it can become reality.
37

Nová koncepce údržby a provozu výrobních technologií / The new concept of maintenance and operation of manufacturing technologies

Klus, Jakub January 2021 (has links)
This diploma thesis deals with a new concept of maintenance and operation of production technologies, where spare parts are manufactured using rapid prototyping methods. The options are compared with currently used methods. Furthermore, methodological recommendations are written on how to proceed with the application. The aim of the work is to evaluate the concept and confirm the theoretical assumptions on a case study.
38

Návrh variantní výrobní technologie oběžného kola ventilátoru / Variant production technology of a fan impeller

Macháček, Marek January 2021 (has links)
The thesis considers a change in the manufacturing technology of a fan impeller from welding to 3D printing. The wish of the manufacturer was to investigate if such a change is possible and financially profitable and decide on a further approach to manufacturing. Models were created using information from the manufacturer and using them, conditions for manufacturing the impeller in the 1:1 ratio were derived. Based on the new technological process and the experience from prints a new price calculation for the fan impeller using 3D printing was created.
39

Kompozitní tisk pro 3D FDM tiskárnu / Composite printing for 3D FDM printer

Műller, Jakub January 2018 (has links)
This diploma thesis deals with the study of 3D printing based on the FDM method. This method focuses on the possibility of using two extruders it means that the composite parts can be printed. This diploma thesis describes the available variants of composite printing currently on the market. Based on the gained knowledge and the availability of 3D printers and software, individual variants of composite parts were printed. A tensile test was performed on these samples to determine the strength characteristics. Additionally, compatibility and adhesion of two selected materials were tested. Based on the testing is made an evaluation of the achieved results, effectiveness and feasibility.
40

Monitorování procesu FDM tisku / Monitoring of FDM printing process

Rafaja, Hynek January 2019 (has links)
The target of this work is the development of a monitoring system for 3D printing by the Fused Deposition Modeling method, which will be able to identify printing error conditions. During the solving process the needed error conditions were identified. Then, an algorithm was programmed to identify the error condition using the criterion. The resulting Monitoring Hardware was implemented in the printer and experimentally verified. A system has been developed that can identify error conditions with an accuracy of 94.7%. The main benefit of this work is the automatic identification of error conditions that stop printing if necessary. This leads to a reduction in scrap and cost savings. In the future, the software could automatically adjust the print parameters when identifying an error condition. This would prevent or completely eliminate the error condition without user intervention.

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