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<p>Multilayer polymer decorative films are showing a growing presence in the automotive industry, substituting conventional paint applications while maintaining similar aesthetic appeal. However for certain film constructions that have distinct layer properties, the polymer film laminates have shown to form wrinkles on application of heat during thermoforming. In this study, attempts were made to identify the factors influencing wrinkling and to predict the variation in the wrinkle parameters under changing forming conditions using existing theoretical models. A new modified thermoforming technique is proposed for producing thermoformed parts without wrinkles and thereby achieving a <em>Class A</em> finished surface.</p> / Master of Applied Science (MASc)

No / Injection moulding techniques have been miniaturised and refined to achieve micromoulding which aims to satisfy the need for mass production of low-cost micro- and nanoscale components. However, the microscale mould cavity features and extreme processing conditions which are inherent in the process can result in larger process variations than conventional injection moulding, with a corresponding increase in the probability of producing an unsatisfactory product. Accurate process diagnosis is required to ensure process reliability but integration of sensors onto the small and highly detailed mould units can be problematic and alternatives may need to be sought. Piezoelectric film ultrasonic transducers were integrated onto the extrusion barrel and mould insert of a micromoulding machine for real-time, non-destructive and non-intrusive process diagnosis with an ultrasonic pulse-echo technique. Polymer degradation owing to excessive heating at the extrusion barrel was successfully probed by measuring the ultrasonic velocities in the polymer at the mould insert. Filling incompleteness of the mould cavity was also sensitively detected by monitoring the ultrasonic energy variation transmitted into the part at different points along the melt flow length. The developed ultrasonic sensors and technique enable optimisation and in-process quality assurance of the moulded parts which ensures that maximum process efficiency can be achieved.

The use of pre-hardened mold steels has increased appreciably over the years; more than 80% of the plastic mold steels are used in pre-hardened condition. These steels are delivered to the customer in finished state i.e. there is no need of any post treatment. With hardness around ~40HRC, they have properties such as good polishability, good weldability, corrosion resistance and thermal conductivity. Machinability is a very important parameter in pre-hardened mold steels as it has a direct impact on the cost of the mold. In normal machining operations involving intricate or near net shapes, machining constitutes around 60% of the total mold cost. Efforts are underway to explore every possible way to reduce costs associated with machining and to make production more economical. All the possible parameters which are considered to affect the machinability are being investigated by the researchers. This thesis work focuses on the effect of prior austenite grain size on the machinability of pre-hardened mold steel (Uddeholm Nimax).  Austenitizing temperatures and holding times were varied to obtain varying grain sized microstructures in different samples of the same material. As it was difficult to delineate prior-austenite grain boundaries, experimental and empirical methods were employed to obtain reference values. These different grain sized samples were thereafter subjected to machining tests, using two sets of cutting parameters. Maximum flank wear depth=0.2mm was defined for one series of test which were more akin to rough machining, and machining length of 43200mm or maximum wear depth=0.2mm were defined for second series of tests which were similar to finishing machining. The results were obtained after careful quantative and qualitative analysis of cutting tools. The results obtained for Uddeholm Nimax seemed to indicate that larger grain sized material was easier to machine. However, factors such as retained austenite content and work hardening on machined surface, which lead to degradation of machining operations were also taken into consideration. Uddeholm Nimax showed better machinability in large grained samples as retained austenite(less than 2%) content was minimal in the large grained sample. Small grained sample in Uddeholm Nimax had a higher retained austenite (7+2%) which resulted in degradation of machining operation and a lesser cutting tool life.

Im Rahmen der Dissertation wurde eine Fertigungstechnologie entwickelt, die die Überleitung des Stahlniederdruckgießverfahrens (3CAST) in die Produktion und somit die Erzeugung des dünnwandigen Stahlgusses ermöglicht. Die konventionellen Stahlgusswerkstoffe sowie ihre Gießbarkeit und Wärmebehandlung wurden untersucht und an die Besonderheiten des neuen Verfahrens und dünnwandigen Stahlgusses angepasst. Auf der Basis von schon existierenden Gießtechnologien wurde eine Formträgertechnologie (FTTech) entwickelt, die unter Berücksichtigung ökologischer Aspekte eine hohe Gussteilqualität und Wirtschaftlichkeit des Gießverfahrens sichert. Die gewonnen Ergebnisse wurden anhand eines Formträgerprototyps unter produktionsnahen Bedingungen erfolgreich erprobt. Somit ist eine Grundlage für den bei der Fa. Evosteel GmbH geplanten Aufbau der Fertigungstechnologie zur Serienproduktion von komplexen dünnwandigen Stahlgussteilen geschaffen.

The diploma thesis focuses on the optimization of technological parameters of plastic injection molding and the study of the influence of technological parameters on the quality of molded test specimens’ type 1A. The quality of molded parts for 3 types of polypropylene (PP) with different melt flow rate (Mosten GB 002, Mosten GB 218, Mosten MA 230) and 1 type of polystyrene (PS) (Krasten PS GP 154) was evaluated in terms of dimensional stability and weight. The contribution of software for modeling the plastic injection molding process was evaluated in this work. SOLIDWORKS Plastics software was used to optimize technological parameters. The construction of the bodies, mold and cooling system was constructed, and test bodies were produced on the basis of parameters obtained from the simulation of the injection molding process. Their quality parameters were compared with a 3D model and for each of the studied materials the optimal technological parameters were selected in terms of quality and the degree of influence of individual injection parameters on the quality of moldings was evaluated. The accordance of the results of the theoretical simulation with the real experiment was proved and a computational module independent of the optimized quality parameters, generally suitable for optimizing the quality parameters of the injected parts, was developed.

Im Rahmen der Dissertation wurde eine Fertigungstechnologie entwickelt, die die Überleitung des Stahlniederdruckgießverfahrens (3CAST) in die Produktion und somit die Erzeugung des dünnwandigen Stahlgusses ermöglicht. Die konventionellen Stahlgusswerkstoffe sowie ihre Gießbarkeit und Wärmebehandlung wurden untersucht und an die Besonderheiten des neuen Verfahrens und dünnwandigen Stahlgusses angepasst. Auf der Basis von schon existierenden Gießtechnologien wurde eine Formträgertechnologie (FTTech) entwickelt, die unter Berücksichtigung ökologischer Aspekte eine hohe Gussteilqualität und Wirtschaftlichkeit des Gießverfahrens sichert. Die gewonnen Ergebnisse wurden anhand eines Formträgerprototyps unter produktionsnahen Bedingungen erfolgreich erprobt. Somit ist eine Grundlage für den bei der Fa. Evosteel GmbH geplanten Aufbau der Fertigungstechnologie zur Serienproduktion von komplexen dünnwandigen Stahlgussteilen geschaffen.:1 Einleitung 2 Stand der Technik „Fertigung dünnwandiges Stahlgusses“ 2.1 Stahlgusswerkstoffe 2.2 Metallurgische Erzeugung 2.3 Gießtechnologie 2.3.1 Schwerkraftguss 2.3.2 Gegenschwerkraftguss 2.3.3 Druckguss 2.3.4 Schleuderguss 2.4 Formtechnologie 2.4.1 Dauerformen 2.4.2 Verlorene Formen 2.4.2.1 Tongebundene Formen 2.4.2.2 Technologie der kalthärtenden Formstoffe 2.4.2.3 Technologie der warmhärtenden Formstoffe 2.4.2.4 Feinguss 2.4.2.5 Vollformguss 2.4.2.6 Vakuumformverfahren 2.4.3 Stützschalenverfahren 2.5 Wärmebehandlung 2.6 Dünnwandiger Stahlguss 2.6.1 Erzeugung 2.6.2 Anwendungsgebiete 3 Aufgaben und Zielstellung der Arbeit 4 Werkstoffentwicklung 4.1 Werkstoffauswahl 4.2 Probenentwicklung 4.3 Untersuchung des Erstarrungs- bzw. Abkühlungsvorganges 4.3.1 Versuchsdurchführung 4.3.2 Ergebnisse der Untersuchung 4.3.3 Diskussion der Ergebnisse 4.4 Wärmebehandlung und Ermittlung mechanischer Eigenschaften 4.4.1 Versuchsdurchführung 4.4.2 Ergebnisse der Untersuchung 4.4.3 Diskussion der Ergebnisse 5 Entwicklung der Formtechnologie 5.1 Konzepterarbeitung 5.1.1 Kernpaket 5.1.2 Formträger 5.1.3 Konturnaher Formträger 5.1.4 Formträger mit Formhinterfüllung 5.2 Vorversuch 5.2.1 Versuchsdurchführung 5.2.2 Ergebnisse der Untersuchung 5.2.3 Diskussion der Ergebnisse 5.3 Entwicklung des Formträgerprototyps 5.3.1 Konstruktion des Formträgerprototyps 5.3.2 Erprobung des Formträgerprototyps 5.3.3 Ergebnisse der Untersuchung 5.3.4 Diskussion der Ergebnisse 5.4 Formstoffentwicklung 5.4.1 Untersuchungen zur Einsetzbarkeit verschiedener Formgrundstoffe 5.4.1.1 Untersuchte Formgrundstoffe 5.4.1.2 Eigenschaften der untersuchten Formgrundstoffe 5.4.1.3 Diskussion der Ergebnisse 5.4.1.4 Gießtechnologische Untersuchungen 5.4.1.5 Ergebnisse der gießtechnologischen Untersuchungen 5.4.1.6 Diskussion der Ergebnisse 5.4.2 Untersuchungen zur Einsetzbarkeit verschiedener Bindersysteme 5.4.2.1 Cold-box-Verfahren 5.4.2.2 Resol-CO2-Verfahren 5.4.2.3 Beach-Box-Verfahren 5.4.2.4 Diskussion der Ergebnisse 5.5 Entwicklung des Formstoffüberzuges 5.5.1 Laboruntersuchungen 5.5.2 Gießtechnologische Untersuchungen 5.5.3 Diskussion der Ergebnisse 5.6 Entwicklung des Formhinterfüllmateriales 5.6.1 Vorversuch mit Formträgerprototyp 5.6.2 Diskussion der Ergebnisse 5.6.3 Entwicklung des Formhinterfüllmateriales 5.6.4 Diskussion der Ergebnisse 6 Wirtschaftliche Betrachtung der entwickelten Technologie 7 Beiträge zur Verbesserung der Umweltbedingungen 8 Zusammenfassung

This thesis overviews my experience during graduate school making tangible,object oriented sculpture. I have been working formally to compose space in a way that develops a narrative between parts. The work is also a bridge between the fields of painting and sculpture, in terms of drawing with form and both painted and local, material color. My palette has mostly consisted of bronze casting, steel fabrication, fiberglass and epoxy resin, paint, the found object, woodworking, and mold making. This work is also conceptually based in showing the hand worked qualities of the materials, the transfer of meaning through casting, and my emotional relationship with the various parts of the sculptures. The three major themes of the work are: divine love and the complex of the apocalypse, the complexities and psychology concerning the relationship between a man and a woman, and the intrigue, potential energy, and beauty of the systems mankind hasinvented to harness the atom. The major artistic influences for this body of work have been: Jasper Johns, Marcel Duchamp, Constantine Brancusi, Alberto Giacommetti, Reg Butler, Henry Moore, Lynn Chadwick, Kenneth Armitage, Jeff Koons, Terry Winters, William DeKooning, Richard Diebenkorn, David Smith and Charles Long. I retain a strongrelationship with the movements of Dada, Surrealism, Futurism, and Assemblage, and amalso currently involved in solidifying the Manifesto of Raubeaux with a small group ofesteemed colleagues.