Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnologico / Made available in DSpace on 2016-01-08T21:24:53Z (GMT). No. of bitstreams: 1 106948.pdf: 5343927 bytes, checksum: 85d7b2ba75f14faa5085f0ddbdb7da87 (MD5) Previous issue date: 1997 / No decorrer deste trabalho são abordadas diversas tecnologias diretamente envolvidas com a usinagem de cavidades de moldes para a indústria do plástico, tais como a usinagem propriamente dita, o estado atual das máquinas de comando numérico e o que se dispõe atualmente, em termos de ferramentas CAD/CAM, para atender as ferramentarias nacionais. São também mostradas três maneiras pelas quais se pode separar as ferramentarias em grupos, para que, utilizando a idéia da Tecnologia de Grupo, se possa classificar estas empresas, segundo sua especialidade, visando atender determinada fatia do mercado. Busca-se com isto agrupar informações a respeito do estado da arte na usinagem CNC de cavidades de moldes para plástico, apresentar uma metodologia que seja aplicável às ferramentarias, já colocadas no mercado, permitindo que estas possam realizar uma escolha adequada dos sistemas de programação para o fresamento de cavidades.Finalmente este trabalho descreve uma aplicação prática (estudo de caso) relacionada com o fresamento da cavidade de um molde, incluindo a programação e a simulação das trajetórias da ferramenta, diretamente no comando de uma máquina, visando demonstrar o potencial de tal tipo de sistema de programação.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde, Programa de Pós-Graduação em Odontologia, Florianópolis, 2015. / Made available in DSpace on 2016-10-19T13:18:54Z (GMT). No. of bitstreams: 1 338968.pdf: 26388567 bytes, checksum: 2069b93e85f123b8ac3c78a879aef322 (MD5) Previous issue date: 2015 / Objetivos: Avaliar o efeito de diferentes tratamentos de superfície e do tempo de armazenamento na resistência de união adesiva à microtração (µTBS) de blocos CAD/CAM do tipo resina-cerâmica. Materiais e Métodos: Dois tipos de blocos CAD/CAM resina-cerâmica (Cerasmart, GC e Enamic, Vita Zahnfabrik) foram seccionados em fatias com 4 mm de espessura, distribuídos em seis grupos e submetidos aos seguintes tratamentos de superfície: Grupo 1: sem tratamento; Grupo 2: jateamento com óxido de alumínio 27 µm + silano; Grupo 3: condicionamento com ácido hidrofluorídrico 5% por 60 seg + silano; Grupo4: condicionamento com ácido fosfórico 37% por 60 seg + silano; Grupo 5: jateamento; Grupo 6: jateamento + silano. Pares de fatias do mesmo material e grupo foram cimentadas umas às outras (n=3 espécimes sanduíches/grupo) utilizando um cimento resinoso dual autoadesivo para os grupos 1 ao 5, e uma resina fluida fotopolimerizável para o grupo 6. Após respectivamente três semanas e 6 meses de armazenamento em cloramina 0,5% à 37oC, os espécimes sanduíches foram seccionados em micro espécimes retangulares, desgastados na interface adesiva (forma de ampulheta) e submetidos ao teste de µTBS. Os dados foram estatisticamente analisados por um modelo linear de efeitos mistos considerando como fatores o tipo de material, o tratamento de superfície e o tempo de armazenamento, assim como suas interações de primeiro grau(p=0,05). Resultados: Independente do tratamento de superfície e tempo de armazenamento, os dois materiais resina-cerâmica apresentaram valores deµTBS sem diferença estatística. Após 3 semanas, todos os grupos obtiveram valores similares. Depois de 6 meses, os valores de resistência adesiva foram mantidos quando foi realizado o JAT com óxido de alumínio (Grupo 263) ou o condicionamento com HF (Grupo 5), ambos seguidos por silanização. O JAT seguido de silanização e o uso de uma resina fluida como agente cimentante também manteve a µTBS. A ausência de tratamento superficial (Grupo 1), o JAT isolado (Grupo 2) e o condicionamento com H3PO4 seguido de silanização (Grupo 6) resultaram em uma diminuição da µTBS. Conclusões: ambos materiais do tipo resina-cerâmica demonstraram µTBS similar, independente do tratamento de superfície. A criação de uma superfície microrretentiva através do JAT com óxido de alumínio ou condicionamento com HF, seguido de silanização, é necessária para manutenção resistência de união adesiva após 6 meses.<br> / Objectives: To evaluate the effect of different surface treatments on the bond strength to resin-ceramic CAD/CAM blocks after six months. Materials and Methods: Two types of resin-ceramic CAD/CAM blocks (Cerasmart, GC; Enamic, Vita Zahnfabrik) were cut in slabs of 4-mm thickness, divided into six groups and subjected to the following surface treatments: Group 1: No treatment; Group 2: Sandblasting (SB); Group 3: SB + Silane; Group 4: SB + Silane; Group 5: 5% Hydrofluoric acid (HF) etching + Silane; Group 6: 37% Phosphoric acid (H3PO4) etching + Silane. Sections of the same group were luted together (n=3 sandwich specimens/group) using a dual-cure self-adhesive cement for all groups, except for Group 4 that were luted using a flowable light-curing composite. After three weeks of storage in 0.5% chloramine at 37oC, the sandwich specimens were sectioned in rectangular micro-specimens and trimmed to an hourglass shape. Part of the specimens was subjected to a micro-tensile bond strength (µTBS) test and the other half was tested after 6 months of storage. Data were statistically analyzed with a linear mixed effects model for the factors surface treatment, material type and storage period, together with their first-degree interactions (p=0.05). Results: The lowest bond strengths were obtained in the absence of any surface treatment (Group 1), while the highest bond strengths were obtained when the surface was roughened by either SB or HF etching, this in combination with chemical adhesion through silanization. Loss in bond strength was observed after six months when either surface roughening or silanization, or both, were omitted. Conclusions: Both resin-ceramic CAD/CAM blocks appeared equally bonding-receptive regardless of the surface treatment. Creating a microretentive surface by either SB or HF etching, followed by chemical adhesion using a silane coupling agent is mandatory to maintain the bond strength after six months.

Made available in DSpace on 2016-04-08T03:07:20Z (GMT). No. of bitstreams: 1 000477935-Texto+Parcial-0.pdf: 597 bytes, checksum: 10775e484d6bf1f1e42f8cc96adb6e1c (MD5) Previous issue date: 2016 / The Computer-aided design/Computer-aided manufacturing (CAD/CAM) system has been widely used for the production of prosthetic restorations. The objective of this study was to analyze the marginal adaptation of veneers made by this technology using different restorative materials. To this they are milled 25 samples of laminates and divided into each following materials tested. Group 1: E-max (lithium disilicate); Group 2: Empress (leucite); Group 3: Lava Ultimate (ceromer); Group 4: Suprinity (lithium disilicate reinforced with zirconium oxide); and Group 5: Vita Mark II (feldspatic). The veneers were cemented in their respective preparations and then we obtained imagens in digital microscopy (Caltex Systems VZM-2003D Digital – Video Mensurement Inspection) with 7. 5X increase. They have been transferred to the software ImageTool for the analysis of marginal gap (mesial and distal; and the third cervical, middle and incisal). It was observed that the largest gap value found in the cervical region of the restoration was made with the Vita Mark II ceramic, and even though there was no statistically significant difference between the ceramic studied (p=0,2 mesial and p=0,4 distal), the incisal third had higher mismatches. It can be concluded that all the ceramics showed good marginal adaptation in the cervical region. / O sistema Computer-aided design/Computer-aided manufacturing (CAD/CAM) tem sido amplamente utilizado para a produção de restaurações protéticas. O objetivo deste trabalho foi analisar a adaptação marginal de facetas laminadas confeccionadas por esta tecnologia utilizando diferentes materiais restauradores. Para tal, foram fresadas 25 amostras de laminados e divididas em cada um dos seguintes materiais testados: Grupo 1: E-max (Dissilicato de lítio); Grupo 2: Empress (Leucita); Grupo 3: Lava Ultimate (Cerômero); Grupo 4: Suprinity (Dissilicato de lítio reforçado com óxido de zircônio) e Grupo 5: Vita Mark II (Feldspática). As facetas laminadas foram cimentadas nos seus respectivos preparos e, então, foram obtidas imagens em microscopia digital (Caltex Systems VZM-2003D Digital – Video Mensurement Inspection) com 7. 5X de aumento. As mesmas foram transferidas para o programa ImageTool para a análise do gap marginal (faces mesial e distal; nos terços cervical, médio e incisal). Observou-se que o maior valor de gap encontrado na região cervical foi da restauração confeccionada com a cerâmica Vita Mark II e, mesmo não havendo diferença estatisticamente significante entre as cerâmicas estudadas (p=0,2 mesial e p=0,4 distal), o terço incisal obteve maiores desadaptações. Pode-se concluir que todas as cerâmicas apresentaram boa adaptação marginal na região cervical.

Orientador: Antonio Batocchio / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-23T16:05:59Z (GMT). No. of bitstreams: 1 Silva_NarcisoAntonioda_M.pdf: 13695611 bytes, checksum: e1b0368d3bd0b39da00972e718b64524 (MD5) Previous issue date: 1998 / Resumo: A utilização de recursos assistidos por computadores como sistemas CAD/CAM e máquinas CNC tem se tomado bastante acentuada no ambiente industrial, propiciando uma série de vantagens aos seus usuários. Em contrapartida, essa utilização também pode incorrer em problemas, como o surgimento de pontos isolados com alto índice de eficiência local, mas que não agregam valor às operações das empresas, principalmente em função da dificuldade de integrar as informações que são geradas e compartilhadas pelas áreas de manufatura. Este trabalho apresenta um modelo conceitual, orientado às necessidades de um fabricante hipotético de máquinas e equipamentos sob encomenda, como uma das formas de melhorar a integração das informações geradas durante a fase de Projeto e que são compartilhadas com outras áreas vinculadas à Manufatura do produto, permitindo a formação de um Banco de Dados comum. Tal modelo utiliza os conceitos de Tecnologia de Grupo e Projeto baseado em Features, sendo que um aplicativo para modelamento CAD (2D) foi desenvolvido para demonstrar sua utilização. A simulação dos resultados obtidos permite verificar a possibilidade de obtenção de melhorias na integração das informações compartilhadas, redução de atividades que não agregam valor ao produto e menor dependência da experiência e intervenção humana para realização de algumas atividades / Abstract: The use of Computer Aided systems such as CAD/CAM and NC machines have been established in the industrial environment as standard because of their ability to increase productivity and quality. But such systems can also be a source of problems if there is not enough attention for the integration of the informations that are shared by the manufacturing areas, which will lead to the growth of"automation islands". This paper presents a conceptual model, oriented to the needs of a hypothetical machine manufacturer, as a method to improve the integration of Design and Manufacturing data and to allow for a common data base formation. This model uses concepts from Group Technology (GT) and Feature-based Modeling methodologies. A sofiware was developed to design 2D rotational parts in a CAD system environment. Afier simulating the use of the presented model the following benefits were achieved: integration of shared informations, reduction of activities that do not agregate value to the product and less dependency on human experience in some activities / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

Orientador: Orlando Fontes Lima Jr / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil / Made available in DSpace on 2018-08-02T03:05:06Z (GMT). No. of bitstreams: 1 Maas_CesarAugusto_M.pdf: 4412306 bytes, checksum: c04ab73baf100264a515f34512efe1d8 (MD5) Previous issue date: 2001 / Resumo: O projeto de terminais intermodais de carga rodoferroviários assume uma importância cada vez maior no cenário nacional, principalmente a partir da privatização das malhas ferroviárias existentes no Brasil. Com a atual competição modal torna-se imperativo buscar eficiência tanto no dimensionamento físico quanto operacional dos terminais. Este trabalho propõe uma metodologia de projeto de terminais intermodais de carga utilizando de forma integrada ferramentas de desenho técnico e de simulação. Esta estratégia propicia o desenvolvimento mais rápido e eficiente de diferentes alternativas de projeto, uma vez que são considerados no projeto tanto os aspectos físicos quanto operacionais dos componentes, além das suas inter-relações. A presente pesquisa foi desenvolvida no âmbito da Faculdade de Engenharia Civil da Unicamp, na área de concentração de Engenharia de Transportes, contando com o apoio da FAPESP ¿ Fundação de Amparo à Pesquisa do Estado de São Paulo / Abstract: The process of designing freight intermodal terminals is growing in magnitude in the Brazilian cenary since the privatization of the former state railways. Given the modal competition at the present time, it is imperative to achieve a high level of efficiency in both physical and operational design of terminals. The aim of this work is to present a design methodology for Freight Intermodal Terminals that combines a computer aided drafting and design tool as well as a simulation tool. This strategy provides a fast, efficient way to develop different options of design, as it is taken into account both the dimensional and operational characteristics, as well as the relationship between the components. This work was developed at the Civil Engineering area, at Unicamp, in the Transportation field, and has been supported since the beginning by FAPESP - Fundação de Amparo à Pesquisa do Estado de São Paulo / Mestrado / Engenharia de Transporte / Mestre em Engenharia Civil

M.Ing. / Please refer to full text to view abstract

M.Sc. / The technique known as "Rapid Prototyping" constitutes a technology that is already saving large corporations time and money in respect of prototyping. Currently, Rapid Prototyping machines are, however, still expensive to purchase and maintain. In order to allow more people to make use of Rapid Prototyping machines, certain businesses are specialising in rendering a Rapid Prototyping service. Rapid Prototyping service bureaux render such service by selling machine time. To allow people to make use of the service, designs are submitted across a distance by means of telemanufacturing. To enable a wide variety of users to avail themselves of this service, certain checks and balances must, however, be put into place. These checks and balances must test whether or not a valid job has been submitted, and if so, the submitter has to be assisted in deciding upon settings. In order to submit a job from anywhere in the world, the Internet is harnassed for telemanufacturing. Once remote submission has been made safe and convenient, more businesses and individuals could derive benefit from Rapid Prototyping. This dissertation has, therefore, been undertaken to identify the prerequisites for Rapid Prototyping. Once a job has been submitted, it has to be checked for errors and the user has to be advised on building types and recommendations. For this, an agent is used. In this way, problems are prevented, should faulty jobs be sent to a Rapid Prototyping machine. Once a job has been submitted, it is scheduled by a queue manager in order to maximise machine usage. Rapid Prototyping has the potential in future to become as commonplace as printers. In terms of this technology, a design would, therefore, be printed in three dimensions for instant verification by the user. The very advantage of being able to hold a new product in one's hands is self-evident. The technology that is being developed today will, therefore, be successfully used in future scenarios.

In the production of removable facial prosthetics, Computer-Aided Design and Manufacture (CAD/CAM) is being increasingly explored. This PhD thesis investigates the application of CAD/CAM in the design and production of components that retain the prostheses to the anatomy. Conventional methods of hand-crafting the retention elements are well established but little research has considered producing these elements using CAD/CAM. A fully digital prosthetic workflow has not yet been developed, and the efficacy of using CAD/CAM for retention mechanism design and fabrication remains unclear. This study firstly focuses on defining the requirements for designing extra-oral prosthesis retention mechanisms, by mapping the various stages of conventional practice and obtaining the opinions of practicing clinicians. Secondly, the qualitative findings are applied to develop a fully CAD/CAM process using existing technologies. Scanning, reverse engineering, design and fabrication technologies are trialled and samples of bar-clip mechanisms are produced. The final stage focuses on developing objective methods to evaluate aspects of bar-clip design previously limited to subjective evaluation, and to make an initial comparison of conventional and CAD/CAM bar-clip mechanisms. This focuses on measuring surface and dimensional quality, accuracy of fit and clip retention forces. This study provides an increased knowledge-base of current prosthetic practice; CAD/CAM prosthesis production and evaluation methods; and insight into the attitudes of clinicians towards the integration & implementation of CAD/CAM. The thesis demonstrates that CAD/CAM can be used to design, produce, and integrate bar-clip retention mechanisms in all aspects of the prosthesis production workflow. Digital measurement methods allow an objective evaluation of the important aspects of bar-clip mechanism design, identifying a number of inaccuracies/design flaws that current evaluation techniques fail to identify. The study concludes that the overall CAD/CAM workflow is not yet appropriate for clinical practice but there is potential in the newly developed processes and this drives future work.

OBJECTIVES: Evaluate the mechanical properties of commercial digital denture base materials. Materials: The materials used were Lucitone 199 denture base disc (Dentsply Sirona), AvaDent denture base puck (AvaDent), KeyMill denture base disc (Keystone), Lucitone digital print denture base resin (Dentsply Sirona), Formlabs denture base resin (Formlabs), and Dentca denture base resin II (Dentca). METHODS: For each material, 60 bar-shaped specimens were prepared for flexural testing, which were divided into 5 groups including control, fatigue, thermocycling, and repairing using 2 types of materials. 24 square-shaped specimens were included in the bond testing, bonded to tooth and composite resin. Additionally, 48 square-shaped specimens were fabricated for the color stability testing, against UV light and staining and washing solutions. The flexural strength and modulus were calculated through 3-point bend test. Bond strength was determined using shear bond test. Color coordinates were recorded in the CIE L*a*b* system using an X-Rite Ci7600 spectrophotometer. Color differences relative to the baseline (∆E^*) were obtained. Data were analyzed using one-way ANOVA followed by Tukey’s HSD test (α=0.05). RESULTS: Milled materials showed higher flexural strength than printed materials. Fatigue and thermocycling led to a decrease in the flexural strength of both group materials. Repaired groups showed flexural strength of about 30.67% and 32.80% of its original strength, in milled and printed materials respectively. However, the flexural strength of the printed materials was affected by the type of the repair material, composite resin gave higher values compared with acrylic. Printed materials exhibited superior bond strength to tooth and composite resin than milled materials. The color change under UV light was clinically acceptable. The color change after immersion in staining and washing solutions in milled groups was less noticeable than in the printed group. Thermocycling treatment made the color change more noticeable in both milled and printed groups. CONCLUSION: Milled denture materials exhibited higher flexural properties than printed denture materials. Printed materials exhibited higher shear bond to tooth and composite resin. The color stability of milled materials with staining and washing solutions treatment was better than the printed groups, whereas the color stability of milled and printed materials exposed to UV light was clinically acceptable. / 2023-08-03T00:00:00Z

A technology of a polishing jig which is made on a CNC lathe with the use of the GibbsCAM system. On the 3D model of the part a NC code of the program is made. This code is imported into the machine and verified for single production. After the production measurement is done. Economic evaluation of the production is calculated for the workpiece price.