Orientador: Luise Weiss / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Artes / Made available in DSpace on 2018-08-24T21:31:09Z (GMT). No. of bitstreams: 1 Silva_WilsonRobertoda_D.pdf: 16280272 bytes, checksum: 11413fbb861442a3e75dea59047ef186 (MD5) Previous issue date: 2014 / Resumo: Esta tese é resultado de uma pesquisa iniciada no mestrado e consiste na produção de estampas predominantemente provenientes de matrizes de gravura em metal e xilogravura, gravadas para serem capazes de permutar suas formas entre elas separadamente e formar combinações complementares, híbridas e aleatórias resultantes do processo de impressão. O principal objetivo é obter o maior número possível de estampas diferentes de um conjunto de matrizes e com isso, não só conciliar visualmente erotismo e anatomia humana na gravura, mas também ressaltar a variedade, como atributo dos organismos que se reproduzem sexualmente e perecem, para dar início a um novo ciclo / Abstract: This thesis is the result of a research started in the master's program and consists of the production of prints mainly from etching plates and woodcut, carved to be able to permute its shapes among them separately and create complimentary, hybrid and random combinations resulting from the printing process. The main goal is to obtain the largest possible amount of different prints from a set of plates and, with that, not only visually conciliate eroticism and human anatomy on the engraving, but also highlight the variety, as an attribute of the organisms that reproduce sexually and perish, in order to initiate a new cycle / Doutorado / Artes Visuais / Doutor em Artes

L’objectif principal de ces travaux de thèse est de caractériser lecomportement et l’endommagement d’un matériau HLE durant le procédé depoinçonnage. Ils comportent dans un premier temps, une étude expérimentale quirepose sur des observations micrographiques et des essais macroscopiques àdifférents états de contrainte, afin d’identifier les mécanismes physiquesd’endommagement mis en jeu. Cette étude est complétée par une modélisationnumérique du modèle d’endommagement de Gurson modifié en cisaillement et sonimplémentation dans ABAQUS/Explicit. Une stratégie d’identification des paramètresmatériau basée sur une large gamme de configurations expérimentales a été mise enplace. Des essais de poinçonnage ont été réalisés en faisant varier le jeu poinçon-matrice, afin de tester la capacité prédictive du modèle de Gurson modifié par rapportau modèle de GTN classique et à un critère découplé basé sur l’initiation de rupture.L’influence du jeu poinçon-matrice sur la qualité de découpe et sur les niveaux desétats de contrainte et de déformation a été également mise en évidence. Lesprédictions de rupture obtenues par cette approche et pour le matériau étudié sont enbon accord avec les observations expérimentales. Il reste à valider le modèle pourdes configurations de couples matériau/procédé plus étendues et à réaliser sonenchainement avec les autres procédés de mise en forme. / The main objective of this thesis is to characterize the behavior anddamage of a HSLA materials during the punching process. They comprise in a firsttime, an experimental study based on micrographic observations and macroscopictests at different stress states to identify the physical mechanisms of damage set in.This study is complemented by a numerical simulation modeling of a Gurson damagemodel modified in shear case and its implementation in ABAQUS / Explicit. Anidentification strategy of material parameters based on a wide range of experimentalconfigurations has been realized. Punching tests were performed by varying thepunch-die clearance to test the predictive ability of the modified Gurson modelcompared to the standard GTN model and to decoupled criterion based on the ductilefracture initiation. The influence of the punch-die clearance blanking quality and instress and strain states levels was also highlighted. Predictions of fracture obtainedby this approach and for the material studied are in good agreement withexperimental observations. It remains to validate the model for larger couple’smaterial/process configurations and realize its concatenation with other formingprocesses.

The project drawn up within the framework of engineering studies in discipline Manufacturing technology (2303T002) presents a proposal for processing a single part – the part is made of sheet steel number S420MC – by blanking, bending and stamping. On the basis of a literary exploration of given problems several variants of processing a part was propounded in order to be made in just one tool. The transfer combined die is fixed in crank press WAINGARTEN ARP 80 with 800 kN nominal force. All functional parts are made of heat treated tool steel number 19 573.3 according to drawing documentation. Lower functional parts of tool (blanking die, stamping die and bending tool) are made as divided.

The project, which have been created within the framework study of engineering branch N2326, submit project technology process of pressing - part from micro-alloyed steel with higher yield point H 240 LA and proposal of tool design for its pressing. Technology process was designed in ten operations, base on literary studying of cold forming technology. Design of progressive die respects type of press machine, which is specified for production this part. Press KRUPP 400t disposes pressing force 4 000kN. Materials, used for design of tool, are in use by tool shops. Punches and punching dies are produced from steels 19 573, heat-treated according drawing documentation. Drawing punches and dies are produced from steel 19 552, hardened on 56+2HRc and coated by TiCN method.

The disertation is focused to the technology of fineblanking. It is concerned to a production of part, which will be used as a mechanism for changing the position of seats in cars. The expected production series is 800.000 pieces per year. With reference to the quantity and demanded quality and also accuracy of blank is choosed precisely technology of fineblanking process with pressure edge. The part will be produced on triple-action press produced by Feintool AG Lyss. It is press GKP – F 160 with mechanical-hydraulic drive. This press and specialy create blanking tool produces two blanks per one action.

Radio astronomy is the discipline dedicated to the study of celestial emissions in the radio band from a few MHz to 300 GHz. In recent years, spurious emissions from man-made devices that operate at these frequencies have made detection of astronomical signals difficult. These harmful RF transmissions are called radio frequency interference (RFI). One strategy to remove RFI is to apply spatial filtering using an array antenna. This thesis documents the development of a high-speed data acquisition system used to record data from 7- and 19-element phased array feeds. The system supports synchronous sampling over all channels and streams data to disk allowing spatial filtering to be applied in post-processing. The development of a time blanking RFI mitigation system was also developed as part of this thesis. Time blanking is a strategy to remove radar interference by blanking the time intervals corrupted by radar transmissions. The two blanking strategies are time window blanking and detected pulse blanking. This thesis documents the design and implementation of a detected pulse blanking system built using FPGAs. The system employs complex signal processing techniques to detect and excise radar transmissions in real time. This FPGA RFI mitigation system is the first to use a matched filter in pulse detection. Successful radio frequency interference mitigation is demonstrated by removing simulated radar interference from a sinusoidal tone.

Orientador: Maria Helena Robert / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / These (docteur) - Universite de Savoie, Ecole Superiore D'Ingenieurs D'Annecy, France / Made available in DSpace on 2018-08-08T16:12:41Z (GMT). No. of bitstreams: 1 Pires_GiselePuime_D.pdf: 10020252 bytes, checksum: d17ac3ccc26b5a239dcb6fa99c211603 (MD5) Previous issue date: 2005 / Resumo: Este trabalho apresenta estudo sobre a viabilidade da estampagem, no estado semisólido, de chapas da liga A5052. Inicialmente, para a obtenção de chapas tixofundidas, chapas comerciais laminadas foram submetidas ao processo de fusão parcial controlada, variando-se os parâmetros tempo e temperatura, com o objetivo de analisar a estampabilidade das chapas no estado sólido. Os parâmetros utilizados foram: fusão parcial a 627°C por 5 e 10 minutos, e 634°C, por 5 e 15 minutos, em chapas com 0,8 mm; fusão parcial a 624°C por 5 e 10 minutos, e 631°C por 5 e 15 minutos, em chapas com 2,0 mm; e fusão parcial a 625, 630 e 635°C por 15 minutos em chapas de 4,0 mm de espessura. As chapas foram caracterizadas com relação à microestrutura, sendo observada homogeneidade estrutural em toda a chapa. Também foram caracterizadas quanto às propriedades mecânicas, sendo que o material tixofundido (obtido por fusão parcial) apresentou diferenças significativas em relação ao material laminado. Para a caracterização da estampabilidade do material, foram feitos ensaios de Erichsen e obtidas curvas limite de conformação de chapas nos estados laminado, recozido e tixofundido, utilizando o método Marciniak e um método de análise de imagens para a obtenção das deformações principais da liga nos diferentes estados. Os resultados mostraram que o material tixofundido apresenta formabilidade semelhante à do material recozido. Foi buscada a caracterização do arranjo espacial de glóbulos em pastas tixofundidas; os resultados mostraram a presença de aglomerados tridimensionais de partículas com evidente interação entre elas, indicando a possibilidade da estrutura suportar esforços de tração. Portanto, para estudos da viabilidade de tixoestampagem, foi construída matriz com geometria tal a apresentar condições severas de conformação. As chapas foram tixoestampadas (temperaturas acima da solidus) e comparadas com chapas estampadas a quente. Observou-se que a tixoestampagem é um processo perfeitamente viável, levando a excelentes resultados de acabamento da peça e redução da força necessária para a obtenção do produto / Abstract: This work presents an analysis of the viability of drawing A5052 sheets in the semisolid state. Initially, to produce thixocast sheets, rolled commercial sheets were submitted to partial melting by different temperatures and holding times, to analyse the sheets draw ability in the solid state. The parameters utilised were: 627°C for 5 and 10 minutes, and 634°C, for 5 and 15 minutes, in sheets of 0,8 mm; 624°C for 5 and 10 minutes, and 631°C for 5 and 15 minutes, in sheets of 2,0 mm; and 625, 630 and 635°C for 15 minutes in sheets of 4,0 mm thickness. The sheets had their microstructure characterised; results showed high homogeneity of the structure throughout the test piece. Mechanical properties of the thixocast material (obtained by partial melting) were also characterised, showing significant differences when compared to the rolled condition. For drawing ability characterisation, Erichsen tests were performed and forming limit diagrams of the sheets in the rolled, annealed and thixocast states were obtained, using Marciniak's technique and image analysis to obtain the main deformations of the alloy in the different conditions. Results showed that the thixocast material shows good formability, similar to the annealed material. Characterisation of the spatial structure of thixocast slurry showed the presence of tridimensional agglomerates of globular solid particles, with evident interaction among globules, indicating the possibility of the structure to stand tensile stresses. Therefore, for thixodrawing tests, a die was especially designed to impose severe flow conditions. The sheets were formed by thixodrawing (temperatures above the solidus) and compared to hot drawing tests. It was observed that thixodrawing is a perfectly viable process, requiring lower forces than conventional solid processing and resulting in excellent finishing products / Doutorado / Materiais e Processos de Fabricação / Doutor em Engenharia Mecânica

Ces travaux de thèse proposent une analyse tribologique de l’opération de découpage sur presse. Une meilleure connaissance des mécanismes d’usure présents sur les poinçons de découpage est nécessaire pour permettre leur reproduction en laboratoire et ainsi tester de nouveaux matériaux d’outils, pour allonger leur durée de vie et augmenter la productivité des outillages. Dans un premier temps un tribomètre de type ouvert est développé afin de recréer les mécanismes d’usure par abrasion présents sur presse. Cette configuration ouverte est choisie car lors de la découpe, l’outil vient découper une pièce sur une surface neuve en continue. Les caractéristiques innovantes de ce tribomètre sont la possibilité d’installer directement des tôles identiques à celles découpées, et les distances de frottement qui peuvent approcher cinq kilomètres sur surface neuve. Une approche énergétique de l’usure est mise en place afin de comparer les résultats obtenus avec le tribomètre et les mesures sur presse. En effet, dans un second temps, des essais réels sur presse à découper avec un outil instrumenté sont conduits. La mesure de l’usure du poinçon par réplication et par activation superficielle sont les deux techniques « in-situ » mises en place lors des essais. Différentes configurations de découpe sont testées afin d’observer leur impact sur l’effort de découpage, l’aspect du bord découpé et l’usure du poinçon. L’usure du poinçon est trop faible dans l’essai de découpage pour être mesurée, mais les taux d’énergie dissipée dans le frottement peuvent être estimés. Dans un troisième temps une comparaison des énergies dissipées dans le frottement sur le tribomètre et sur presse montre d’importants écarts. Pour les expliquer, une simulation par éléments finis de l’opération de découpe est conduite. Une prédiction de l’usure est établie afin de montrer le potentiel de la méthode d’approche énergétique. Une analyse vibratoire de l’outil montre que la phase de fissuration de la tôle induit des oscillations parfois nombreuses du poinçon qui peuvent conduire à de l’usure par fatigue. Des essais d’usure par fatigue sont réalisés et montrent que suivant les nuances, le carbure de tungstène usiné par électroérosion à fil est moins résistant à l’écaillage. / This work proposes a tribological analysis of the blanking operation. A better knowledge of the wear mechanisms present on the cutting punches is necessary to allow their reproduction in the laboratory and thus to test new tools materials, to extend their life time and increase the productivity of the process. Firstly, an open-type tribometer is developed in order to recreate the abrasive wear mechanisms present on the press. The innovative characteristics of this tribometer are the possibility of directly installing sheets identical to cutting pieces, and the friction distances can approach five kilometers on new surface. An energy approach of the wear is conducted in order to compare the results obtained with the tribometer and measurements on the press. Secondly, real tests on a cutting press with an instrumented tool are carried out. The measurement of the wear of the punch by replication and thin layer activation are the two "in-situ" techniques put in place during the tests. Differents cutting configurations are tested in order to observe their impact on the cutting force, the appearance of the cut edge and the wear of the punch. The wear of the punch is too low in the cutting test to be measured, but the rates of energy dissipated in the friction can be estimated. Thirdly, a comparison of the dissipated energies of friction on the tribometer and on the press shows significant deviations. To explain them, a finite element simulation of the cutting operation is carried out. A prediction of wear is established to show the potential of the energetic approach. A vibratory analysis of the tool shows that the phase of cracking of the sheet induces sometimes numerous oscillations of the punch which can lead to wear by fatigue.

Project elaborate in terms of engineering studies branch 2303T002 submits proposal technology of production single parts from deep drawing press steel metal plate 11 305.21. On the basis literary study problems blanking, deep drawing and calculations was designed drawing in instrument with holder, to extrusion components serves lower ejector. Combination tool is set on hydraulic press CTH 250 with nominal tensile by force 250 kN. Drawable tools (drawing punch, drawing die) and shear pin tools (blanking punch, blanking die) are made from instrumental steels 19 436.3, heat treated condition to drawing documentation.

MIKYSKA Josef: The manufacture of hold-down arm by technology of fine blanking process. The diploma thesis deals with innovative technology of „hold-down arm“ by fine blanking technology. The component is made of steel plate no. 12 041.20, 3mm thick. The theoretical part presents possible solutions. In the project there are compared versions of fine blanking technology. Regarding the required size accuracy, surface quality and assumed series production of 600 000 pieces per year the fine blanking technology using V-ring was proposed as the innovative technology. On the basis of technological calculations the triple action hydraulic press GKP-F 100 (produced by Feintool) and a blanking tool were determined. The blanking tool solution is accomplished including calculations and futher documentation. Then, the project implies technical and economical evaluation of the present technology ( conventional blanking with consequentional cutting) and of the newly designed technology. According to the analysis using the newly designed production technology economic and time savings are achieved.