07 Fakultät Konstruktions-, Produktions- und Fahrzeugtechnik

Permanent URI for this collectionhttps://elib.uni-stuttgart.de/handle/11682/8

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    Systematisches Toleranz Design unter Berücksichtigung von Funktions- und Kostenaspekten nach der robusten Zuverlässigkeitsmethode SMAR²T
    (2015) Kemmler, Stefan; Fuchs, Alexander; Leopold, Tobias; Bertsche, Bernd
    Tendenzen für heutige Herausforderungen zur effizienten Produktentwicklung verlagern sich in Richtung von simulativ gestützten virtuellen Herangehensweisen. Hierfür werden in der industriellen Entwicklung komplexer Produkte zunehmend Methoden angewandt, die unter Einsparung von notwendigen Ressourcen umfassende realitätsnahe Ergebnisse liefern. Diese Ergebnisse werden zielgerichtet an die jeweilige Anforderung unter Berücksichtigung deren Robustheit, technische Realisierbarkeit sowie Kosten bezüglich variierender Toleranzeinstellungen, optimiert. Zur Veranschaulichung der methodischen Vorgehensweise zum Gestalten robuster und zuverlässiger Produkte unter Berücksichtigung von Funktions- und Kostenaspekten wird die Vorgehensweise zur Bestimmung eines Kostenmodells im Toleranz Design nach SMAR²T (Systematic Method for Axiomatic Robust Reliability-Testing Method) anhand eines einfachen technischen Systems (Überlastkupplung) diskutiert.
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    Local laser heat treatment of AlSi10Mg as-built parts produced by Laser Powder Bed Fusion
    (2024) Kramer, Steffen; Jarwitz, Michael; Schulze, Volker; Zanger, Frederik
    Today, complex structural components for lightweight applications are frequently manufactured by laser powder bed fusion (PBF-LB), often using aluminum alloys such as AlSi10Mg. However, the application of cyclic load cases can be challenging as PBF-LB produced AlSi10Mg parts typically have low ductility and corresponding brittle failure behavior in the as-built condition. Therefore, this paper presents investigations on the feasibility of a laser heat treatment of PBF-LB produced AlSi10Mg parts to locally increase the ductility and decrease the hardness in critical areas. Potential heat treatment process parameters were derived theoretically based on the temperature fields in the material calculated assuming three-dimensional heat conduction and a moving heat source. PBF-LB produced specimens were then laser heat treated at varying laser power and scan speed. Hardness measurements on metallographic cross sections showed hardness reductions of over 35 % without inducing hydrogen pore growth.
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    Influence of geometry variations during pyrometric temperature measurement in laser material processing
    (2024) Traunecker, David; Jarwitz, Michael; Michalowski, Andreas
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    Influence of protection lips on the frictional torque of rotary shaft seals
    (2024) Olbrich, Christoph; Feldmeth, Simon; Bauer, Frank
    Rotary shaft seals are used to seal rotating machine parts. In most cases one single sealing lip (main lip) contacts the shaft and separates the fluid on one side from the environment on the other side. To prevent the entry of other fluids and or particles, seals with additional protection lips are used (two lips), especially in heavily contaminated environments. When the protection lip contacts the shaft, a vacuum can form between the main lip and the protection lip, leading to increased contact pressure and friction. The increased frictional torque generates more heat and leads to overheating in the contact area between the lip and the shaft. Test runs conducted on a friction torque test bench with various seal configurations confirm that the two lips influence each other. Higher frictional torques and contact temperatures occur, when the volume between the lips isn't vented. This shows the importance of venting.
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    Stream finishing of additively manufactured AlSi10Mg PBF-LB parts: influence on surface quality and fatigue behaviour
    (2024) Wexel, Helena; Kramer, Steffen; Schubert, Johannes; Schulze, Volker; Zanger, Frederik
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    Towards learning human-seat interactions for optimally controlled multibody models to generate realistic occupant motion
    (2023) Fahse, Niklas; Harant, Monika; Roller, Michael; Kempter, Fabian; Obentheuer, Marius; Linn, Joachim; Fehr, Jörg
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    Rasselgeräuschprüfstand zur Untersuchung von Fahrzeuggetrieben
    (2011) Fietkau, Peter; Baumann, Axel; Bertsche, Bernd
    In diesem Aufsatz wird der Klapper- und Rasselgeräuschprüfstand am Institut für Maschinenelemente der Universität Stuttgart vorgestellt. Der Prüfstand wurde speziell entwickelt, um die bei Fahrzeuggetrieben auftretenden Losteilgeräusche (Klapper- und Rasselgeräusche) untersuchen zu können. Neben der Beschreibung des allgemeinen Prüfstandsaufbaus wird genauer auf das Regelungskonzept sowie die verwendete Messtechnik eingegangen. Diese zeichnet sich unter anderem durch eine hochgenaue Erfassung der Drehschwingungen aus. Dadurch ist es möglich, Relativbewegungen im Betrieb von im Eingriff stehenden Zahnrädern hochauflösend aufzuzeichnen. Abschließend werden einige exemplarische Messungen dargestellt.
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    Inverse fuzzy arithmetic for the quality assessment of substructured models
    (2015) Iroz, Igor; Carvajal, Sergio; Hanss, Michael; Eberhard, Peter
    The dynamical analysis of complex structures often suffers from large computational efforts, so that the application of substructuring methods has gained increasing importance in the last years. Substructuring enables dividing large finite element models and reducing the resulting multiple bodies, yielding a reduction of, in this case, complex eigenvalue calculation time. This method is used to predict the appearance of friction-induced vibrations such as squeal in brake systems. Since the method is very sensitive to changes in parameter values, uncertainties influencing the results are included and identified. As uncertain parameters, standard coupling elements are considered and modeled by so-called fuzzy numbers, which are particularly well suited to represent epis- temic uncertainties of modeled physical phenomena. The influence of these uncertainties is transferred to undamped and damped eigenfrequencies of a substructured model by means of direct fuzzy analyses. An inverse fuzzy arithmetical approach is applied to identify the uncertain parameters that optimally cover the undamped reference eigenfrequencies of a non-substructured, full model. If a validity criteria is defined, a positive decision in favor of the most adequate model can be performed.
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    Comparison of driver models for powertrain test benches using a digital twin
    (2023) Schilling, Jannes; Wilmsen, Jan-Michael; Nitschke, Paul; Reuss, Hans-Christian