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Desenvolvimento de interface entre o projeto auxiliado por computador e a administração de materiaisGimenez, Claudemir 31 January 1996 (has links)
Orientador: Geraldo Nonato Telles / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-21T06:15:18Z (GMT). No. of bitstreams: 1
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Previous issue date: 1996 / Resumo: Cabe à área de projetos da empresa a definição dos produtos que serão concebidos para atender às necessidades do mercado. Existe atualmente uma ampla gama de programas para a área de projeto. Raramente esses programas permitem o intercâmbio (com outros departamentos) de informações sem restrições. Neste trabalho apresenta-se o desenvolvimento de uma interface, com o objetivo de extrair informações referentes aos materiais e componentes de um projeto, desenvolvido no ambiente CAD. Paralelo a esse trabalho, planeja-se os materiais que constituem o projeto, com o auxílio de uma planilha MRP / Abstract: The design function attempts to ensure that products meet market needs. Many programs have been developed to assist in the design function. Rarely do these programs permit the exchange of information with other departments without restrictions. This work outlines the development of an interface to extract information (such as the bills for materiais), in a CAD (Computer Aided Design) environment. In addition, the materiais are organized in MRP (Materiais Requirements Planning) system / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica
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Aplicando o evento KAIZEN na redução do ciclo de desenvolvimento de programas de usinagem para máquinas CNCOsvaldo Massaharu Ito 10 September 2012 (has links)
Due to an extremely competitive market in recent years, the sector of aviation industry requires speed and agility to meet their external customers needs. To be competitive, it is necessary to produce parts that will make a quality product quickly in a way to reduce costs and increase agility in manufacturing. This dissertation presents a case study conducted in an industry of the aerospace segment with the purpose of finding alternatives for productivity gain, using lean thinking tools, specially the kaizen events (KE), in the development of machining programs for CNC machines, interconnected by CAD-CAM software. This method has been used with success in several industries leading to efficiency gains in solving problems of productivity, at low cost. During the implementation of KE, the work team implemented the value stream mapping (VSM), as an attempt to increase the value added in the preparation of the machining program and to meet the needs of the internal customer (production department). By using this methodology it was possible to reduce the average time of the development cycle of the NC programs in approximately 50% and the average number of hours spent to create the programs was also reduced in approximately 51%.
Among several opportunities found during the preparation of current VSM, one of the major contributions to the productivity improvement resulted from the adoption of the continuous working flow practice. / Com o mercado extremamente competitivo nos últimos anos, o setor da indústria aeronáutica necessita de agilidade e rapidez para atender às necessidades dos clientes externos. Para ser competitivo torna-se necessário produzir peças que irão compor o produto rapidamente e com qualidade, de forma a reduzir os custos e aumentar a agilidade na fabricação. Esta dissertação apresenta um estudo de caso realizado numa indústria do segmento aeronáutico com o objetivo de encontrar alternativas para obter ganhos de produtividade no desenvolvimento de programas de usinagem para máquinas CNC, interligadas a softwares CAD-CAM, por meio da aplicação de ferramentas do pensamento enxuto, com ênfase em eventos Kaizen (EK). Este método esta sendo utilizado em várias indústrias com êxito e proporcionando ganhos de eficiência na solução de problemas de produtividade, com custo baixo. Durante a execução do EK, a equipe de trabalho implementou o mapeamento do fluxo de valor (MFV), buscando aumentar o valor agregado na elaboração do programa de usinagem, visando atender às necessidades do cliente interno (produção). A aplicação da metodologia tornou possível reduzir o tempo médio do ciclo de desenvolvimento da programação CN em aproximadamente 50% e o número médio de horas gastas para a criação dos programas em aproximadamente 51%. Dentre as diversas oportunidades encontradas durante a elaboração do MFV atual, destaca-se a criação dos programas de usinagem em fluxo contínuo para a obtenção destas melhorias.
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Modelo de produto como integrador em sistemas de manufaturaBarra, Rogerio Almeida 26 September 1989 (has links)
Orientador: Manuel de Jesus Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica / Made available in DSpace on 2018-07-14T03:17:23Z (GMT). No. of bitstreams: 1
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Previous issue date: 1989 / Resumo:Os sistemas de manufatura da década de noventa se caracterizarão por uma utilização maciça de computadores. Visando a automação das tarefas envolvidas no ciclo de projeto e manufatura de produtos. Neste sentido, as empresas têm feito grandes investimentos em sistemas CAD. CAN. m.á.quinas CNC. Robôs, etc. O conceito de Manufatura Integrada por Computador-CIM surge da necessidade de que estes sistemas cooperem entre si. a fim de que a empresa opere em um nível máximo d. eficiênc1a. Para isto. Deve ser possível transferir entre sistemas. Dados que tenham um significado comum a eles. de t.al forma que possam ser utilizados pelo sistema que os recebe. Uma parte significativa destes dados a serem trocados diz raspei t.o a. produtos. Neste contexto este trabalho tem por objetivos definir que requisitos um modelo de produto deve satisfazer a fim de prover às aplicações em um sistema CIM todas as informações que elas necessitem verificar os esforços de padronização deste modelo e a relevância destes no que diz respeito à implantação de um sistema que possibilite um efetivo compartilhamento de 1nformações sobre produtos entre seus componentes. Como resultado final é proposta uma arqu1tetura para este sistema / Abstract: Manufacturing systems of the nineties will be distinguished by massive computer use, aiming at automation of tasks along the product design and manufacturing cycle. Thus, companies have invested heavily on CAD/CAM systems, CNC machines, robots, etc. The concept of Computer Integrated Manufacturing-CIM arises from the necessity that these systems cooperate, so that the company operates at a maximum efficiency level. For this, it must be possible transfer, among these systems, data that have a meaning common to them, so that they can be used by the system receiving them. Significant part of the data to be exchanged relates to products. In this context this work intends to define which requirements a product model must. Satisfy in order to provide to applications within a CIM system alI 1nf'ormation they need, verify the efforts to standardize this model and their relevance concerning the implementation of' a system that enables an effective product information sharing among its components. As a final result_ architecture for this system is proposed. / Mestrado / Mestre em Ciências
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Intelligent STL file correctionVan Niekerk, G.J. 05 September 2012 (has links)
M.Sc. / Layered Manufacturing (LM), also known as "Rapid Prototyping", is that process in terms of which a computer-designed model is created layer by layer with the aid of specific LM hardware. Telemanufacturing constitutes an extension of this technology that allows remote submission of manufacturing jobs or assignments across a communication medium, typically the Internet, to be built at the manufacturing bureau concerned. The de facto standard of LM is the STL file. Simply put, this file consists of a number of triangles that are used to describe an object in its entirety. This file format has several advantages over other known formats and allows easy 2D rendering. Unfortunately, however, the limitations of the latter format outweigh its advantages. Since the entire model is described in terms of a collection of triangles, the original geometry of the model is lost. As a result, a certain level of degradation will occur, especially around curvatures in the model. Although an increase in the number of triangles around such areas will enhance precision, it will also result in a much larger STL file. Triangles that get lost somewhere inside the file could also give rise to holes, orphaned surfaces and zero-width walls in the projected object. It is vital, therefore, that the manufacturing bureau verify the correctness of the entire file before it is built in order to prevent machine time and materials from being wasted. Instead of transmitting the entire file again, the bureau could attempt automatically to correct and repair less critical errors, thereby saving valuable resources and time.
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An implementation framework for knowledge-based engineering projectsMvudi, Yannick 27 May 2013 (has links)
M.Ing. (Engineering Management) / The growing need for customized solutions and faster product delivery obliges the product development industry to develop new strategies that can enable the rapid and flexible design of products. Several design approaches have been developed to address this issue: one such is Knowledge-Based Engineering (KBE), which is a design technique that enables the automation of the design process. This approach consists of using computational intelligence to capture the design rules related to a product family in order to generate automatically customized designs adapted to particular customer requirements. Knowledge-Based Engineering is also used to facilitate the performance of design evaluation activities such as finite element analysis (FEA) and computational fluid dynamics (CFD) as part of multi-disciplinary design optimization (MDO). The application of this approach led to impressive results mostly in the automotive and aeronautical industry. Owing to this method, some companies manage to reduce the duration of the design process by 90%. Despite the excellent results obtained through the use of Knowledge-Based Engineering, there are still very few companies that make use of this approach in their design process. The review of the relevant literature showed that the lack of a standard easy-to-use methodology of implementation is one of the major obstacles to the expansion of Knowledge-Based Engineering. The knowledge processing phase constitutes one of the main challenges of the KBE implementation process. This phase consists of extracting and documenting the knowledge embedded in the design team in order to convert it in a programming code. Available methodologies such as MOKA and KNOMAD do not seem to provide easy-to-use methods to represent the design knowledge in a form that makes it easy to be programmed. The lack of a preliminary stage that justifies the adequacy of KBE for a particular design process is also an important gap identified in the literature.This dissertation discusses a detailed method that addresses issues related to knowledge processing and suitability analysis in KBE implementation. The knowledge processing method suggested is based on the Work Breakdown Structure (WBS) which is used widely in the system engineering approach and consists of a very logical classification of the design knowledge. The strength of this method lies in its ability to represent the design knowledge in a form that makes it understandable for both engineers and programmers. Appropriate representation of this sort shortens the duration of the knowledge processing and facilitates the knowledge programming phase. Regarding the rationale for choosing of KBE, a detailed suitability assessment method is proposed.
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Bloc composite dentaire thermo-polymérisé sous haute pression favorable pour la CFAO / Dental resin composite block thermopolymerized at high pressure suitable for CAD/CAMPhan, Anh chi 27 May 2015 (has links)
Nouvelle classe de composites dentaires, plus performants, pour la CFAO via la polymérisation à haute température sous haute pression (HT-HP). La polymérisation à HT-HP permet d'obtenir un réseau polymère plus homogène avec les propriétés mécaniques, physiques et viscoélastiques améliorées et une diminution très importante du relargage de monomère. En plus, notre étude a montré aussi que 200 MPa est la pression optimum qui permet d'aboutir à cet ensemble des propriétés supérieures. En outre, des blocs composites ont été réalisés par un nouveau procédé d'infiltration d'un réseau céramique par monomère, ce qui a abouti au PICN (Polymer-Infiltrated-Ceramic-Network) avec des propriétés mécaniques, physiques et chimiques améliorées. En conclusion, cette étude permet d'introduire une nouvelle génération de blocs composites (PICN) avec des propriétés améliorées laissant entrevoir une application clinique dans un proche avenir. / The aim of this study was to improve the properties of composite blocks for a new class of high performance composites for dental CAD/CAM via high-temperature high-pressure polymerization (HT/HP). Polymerization under HT/HP results into a more homogeneous polymer network with improved mechanical, physical and viscoelastic properties and a very significant decrease in monomere release. In addition, our study also shoxed that 200 MPa is an optimum pressure that allows to reach this set of superior properties. Moreever, composite blocks were made by a new method of infiltrating a ceramic network with monomer, wich resulted in PICN (Polymer-Infiltrated-Ceramic-Network) with improved mechanical, physical and chemical properties. In conclusion, this study introduced a new generation of composite blocks (PICN) with improved properties, blocks that may find clinical applicability in CAD/CAM dentistry in the near future.
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Cimentação adesiva de materiais CAD/CAM resina-cerâmicaLise, Diogo Pedrollo January 2015 (has links)
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 2016-05-24T17:52:33Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015 / Objetivos: Avaliar o efeito de diferentes tratamentos de superfÃcie 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, distribuÃdos em seis grupos e submetidos aos seguintes tratamentos de superfÃcie: Grupo 1: sem tratamento; Grupo 2: jateamento com óxido de alumÃnio 27 µm + silano; Grupo 3: condicionamento com ácido hidrofluorÃdrico 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 à s outras (n=3 espécimes sanduÃches/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 sanduÃches 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 superfÃcie e o tempo de armazenamento, assim como suas interações de primeiro grau(p=0,05). Resultados: Independente do tratamento de superfÃcie e tempo de armazenamento, os dois materiais resina-cerâmica apresentaram valores deµTBS sem diferença estatÃstica. 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 alumÃnio (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 superfÃcie. A criação de uma superfÃcie microrretentiva através do JAT com óxido de alumÃnio 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.
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in-vitro Untersuchungen zum Haftkraftverhalten herkömmlicher und moderner Doppelkronensysteme / In vitro investigations on retention force behavior of conventional and modern double crown systemsLuft, Viktor January 2020 (has links) (PDF)
Ziel der Studie
Das Ziel dieser in-vitro-Studie war die Untersuchung des Einflusses einer künstlichen Alterungsphase von 10.000 Füge- und Trennzyklen unter Speichelschmierung auf das Haftkraft- und Verschleißverhaltens von konventionell gusstechnisch, galvanisch und im CAD/CAM-Verfahren hergestellten Parallelteleskopen.
Material und Methode:
Sechs verschiedene Prüfgruppen unterschiedlicher Materialkombinationen und Fertigungsweisen wurden ausgehend von einem gemeinsamen Primär- und Sekundärkronendesign zu je zehn Parallelteleskopen (n = 10) angefertigt:
Gruppe 1 (GG): Gruppe 2 (NN): Gruppe 3 (ZG): Gruppe 4 (CC NN): Gruppe 5 (CC ZN): Gruppe 6 (CC ZP):
Hochgoldhaltige Legierung (Gussverfahren)
Edelmetallfreie Legierung (Gussverfahren) Zirkoniumdioxidkeramik/Galvanogold (Galvanotechnik) Edelmetallfreie Legierung (CAD/CAM) Zirkoniumdioxidkeramik/Edelmetallfreie Legierung (CAD/CAM) Zirkoniumdioxidkeramik/Polyetheretherketon (CAD/CAM)
Unter Verwendung einer Vorlast von 50 N wurden die Haftkraftwerte in der Universalprüfmaschine (Zwick/Roell, Ulm, Deutschland) kontinuierlich aufgezeichnet und zu den Zeitpunkten t0 (= Ausgangszustand), t1 (= 50 Zyklen), t2, (= 5.000 Zyklen) und t3 (= 10.000 Zyklen) miteinander verglichen. Die Daten wurden unter Anwendung eines Kolmogorov- Smirnov-, Friedman-, Wilcoxon-Vorzeichen-Rang-, Kruskal-Wallis- und Mann-Whitney-U-Test bei einem Signifikanzniveau von p ≤ 0,05 ausgewertet (SPSS, V25). Zusätzlich wurden lichtmikroskopische Aufnahmen der Primärkronenoberflächen und Sekundärkroneninnenseiten zum Nachweis von Verschleißphänomenen durchgeführt. Zur Bestimmung der Linien- und Oberflächenrauheit dienten konfokalmikroskopische Aufnahmen der Patrizen.
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Zusammenfassung
Ergebnisse
Bei allen Prüfgruppen wurde eine Abnahme der mittleren Haftkraftwerte registriert. Die geringsten Haftkraftverluste wiesen die gegossenen hochgoldhaltigen Teleskopkronen mit 1,58 % (GG), die größten Haftkraftverluste mit 36,17 % die gegossen edelmetallfreien Doppelkronen (NN) auf. Signifikante Haftkraftverluste präsentierten nach Durchlaufen der Belastungsphase ausschließlich die galvanischen und gefrästen ZrO2/PEEK Probekörper, die zugleich die höchsten und niedrigsten mittleren Haftkräfte demonstrierten (ZG: t0= 8,30N, t3= 6,20N; CC ZP: t0= 1,36N, t3= 1,25N; Wilcoxon-Vorzeichen-Rang-Test; pZG= 0,010, pCC ZP= 0,049). Die Retentionskräfte der gegossenen hochgoldhaltigen und edelmetallfreien Gruppen sowie der gefrästen Prüfgruppe der Materialkombination ZrO2/NEM (GG, NN , CC ZN) unterschieden sich zu keinem der Zeitpunkte t0-t3 signifikant und zeigten ebenfalls über die gesamte Versuchsdauer keinen signifikanten Haftkraftrückgang. Hingegen wichen zu allen Zeitpunkten t0-t3 die Retentionskräfte der metallfreien Doppelkronen (CC ZP) signifikant von allen anderen Materialkombinationen ab. Bei nahezu allen Probekörpern waren im Bereich der Kontaktflächen zwischen Primär- und Sekundärkronen Verschleißerscheinungen erkennbar. Lediglich die keramischen Primärkronen der Materialkombination ZrO2/PEEK unterlagen keinen Oberflächenveränderungen. Die geringste Linienrauheit und Oberflächenrauheit zeigten die Primärkronenoberfläche der frästechnisch hergestellten edelmetallfreien Doppelkronen (CC NN; Rat0= 0,0869 μm, Rat3= 0,125 μm, Sat0= 0,109 μm, Sat3= 0,180 μm). Die höchsten Rauheitswerte wurden für die keramischen Primärkronen der Gruppen ZG und CC ZP dokumentiert (ZG: Rat0= 0.454 μm, Sat0= 0.544 μm, Sat3= 0.612 μm; CC ZP: Rat3= 0.462 μm).
Schlussfolgerung
Unter den gewählten Versuchsbedingungen erreichten alle getesteten Herstellungsmethoden und Materialkombinationen klinisch suffiziente Haftkraftwerte, obwohl sich zwischen den einzelnen Prüfgruppen ausgeprägte Unterschiede hinsichtlich des Haftkraftverhaltens offenbarten. Während in diesen Untersuchungen die hochgoldhaltigen Legierungen im Bereich Teleskoptechnik den Grund für ihre langjährige Bewährung belegten, zeigte sich bei der ausschließlichen Verwendung edelmetallfreier Legierungen die frästechnische Herstellung der Gusstechnik aufgrund homogenerer und höherer Retentionswerte überlegen. Die Materialkombination aus Zirkoniumdioxidkeramik und Nichtedelmetall stellt eine ästhetische Alternative zur Galvanotechnik dar. In weiteren Untersuchungen sollte die
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Zusammenfassung
Passung und die Haftkraft der Materialkombination Zirkoniumdioxidkeramik/PEEK durch Variation der Fertigungsparameter optimiert werden. Insgesamt vermochte die CAD/CAM- Technologie dennoch ähnlich voraussagbare Ergebnisse wie der sich behauptende Goldstandard zu erzielen. Verschleiß ist elementarer Bestandteil des tribologischen Systems der Doppelkrone und wurde bei allen Prüfgruppen nachgewiesen. Im Allgemeinen erwies sich die Konfokalen Mikroskopie als geeignete Methode zur Bestimmung von Rauheits- und Flächenparametern bei Doppelkronenoberflächen. Ausgehend von den vergleichbaren Untersuchungsergebnissen stellt die CAD/CAM-Technologie für die tägliche Praxis unter Berücksichtigung der leichteren Friktionseinstellung im Herstellungsprozess, einer uneingeschränkten Reproduktion der Doppelkronen aufgrund der digitalen Speichermöglichkeit und der Reduktion von Kosten durch Zeit und Arbeitskraft eine ernstzunehmende Alternative zur konventionellen Guss- und Galvanotechnik dar. Die Eignung von CAD/CAM-gefertigten Doppelkronen sollte jedoch zusätzlich in klinischen Langzeituntersuchungen nachgewiesen werden. / Objective:
This study aimed to investigate the effects of long-term use on the retention force and wear behavior of double crown systems.
Methods:
Based on a common double crown design sixty pairs of telescopic crowns were fabricated and divided into six groups, each consisting ten samples: “Gold standard” cast gold alloy primary and secondary crown (GG) and cast non-precious alloy (NN), computer-aided design (CAD)/computer-aided manufacturing (CAM)-milled zirconia primary crown and galvanoformed secondary crown (ZG), CAD/CAM-milled non-precious alloy primary and secondary crown (CC NN), CAD/CAM-milled zirconia primary crown and non-precious alloy secondary crown (CC ZN) and CAD/CAM-milled zirconia primary crown and polyetheretherketone (PEEK) secondary crown (CC ZP). In the constant presence of artificial saliva, all samples were subjected to 10,000 joining-separation cycles at a velocity of 120 mm/min. Wear was analyzed by reflected light microscopy and confocal microscopy before and after artificial aging.
Results:
Retention force losses were observed in each group after long-term use, with significant losses in the groups ZG and CC ZP (pZG = 0.01, pCC ZP = 0.049). During artificial aging, no significant differences in pull-off force were recorded for groups GG, NN and CC ZN. Regarding wear, merely the Y-TZP primary crowns of the CC ZP group displayed no surface changes.
Significance:
All tested production methods and material combinations seem to be suitable for clinical practice. CAD/CAM technology allows similarly predictable results to be achieved as the gold standard. Confocal microscopy is recommended for surface examinations of double crowns.
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Optimalizace obrábění keramických polotovarů / Milling optimization of ceramic blanksRáčková, Jana January 2018 (has links)
The master thesis deals mainly with the optimization of machining of ceramic semi-finished products from ZrO2 and Al2O3. The first part with literary research, which describes the steps of the technology of forming ceramic bodies, especially the gelcasting method. The thesis describes possibilities of milling of ceramic materials using CNC technology. The thesis describes the dependence of acquired roughness on bodies and used machining strategies. The best roughness parameters on ZrO2 samples were obtained after they were calcined at 900 ° C, while the lowest roughness was obtained on the samples in the unprotected state for the Al2O3 samples. Samples machined with a spherical milling cutter showed surface roughness Ra = 1 m for ZrO2 and Ra = 1.3 m for Al2O3. It also describes the possibility of machining sharp-edged shapes and fine details where the best results are achieved on ZrO2 samples engraved at 900 and 1100 °C. Tool wear was particularly important when machining samples of Al2O3 ignited at temperatures above 800 °C.
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Aplikace CAD/CAM softwaru WorkNC při obrábění / Application of WorkNC CAD/CAM software for machiningKuchař, Petr January 2019 (has links)
The aim of this thesis was to design core and cavity part of the injection moulding tool with regard to the possibilities of SKD Bojkovice company. The structure of the thesis was divided into two main parts - the theoretical part, where the necessary theory for the elaboration of the second part, the practical one was briefly introduced. In the practical part own plastic component was designed, constructed an injection mold with emphasis on the core and cavity parts of the injection moulding tool and produced the necessary production documentation. Subsequently, the process of manufacturing these parts of the mold was described, and a brief technical-economic evaluation of the manufacturing process took place at the very end.
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