TY - CHAP A1 - Leubecher, Dominik A1 - Vitale, Pablo A1 - Musil, Bruno A1 - Brier, Steffen A1 - Höfer, Philipp ED - Huber, Otto ED - Bicker, Marc ED - Patzelt, Peter T1 - Analysis and interpretation of the temperature field in additive material extrusion process for small and large scale components: A numerical study T2 - Tagungsband 11. Landshuter Leichtbau-Colloquium: Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien N2 - Large-scale material extrusion processes, especially for thermoplastic polymers, have become increasingly common in research and industry in recent years. Due to the new time and size dimensions of the extrudate strands to be deposited, compared to small-scale manufacturing processes, challenges are revealed that have not yet been sufficiently researched to this extent. The present work is intended to make a numerical contribution to this in order to obtain a better understanding of the manufacturing processes and to investigate the influences on the temperature field as a result of different printing parameters and the selected deposition path. Further a workflow is presented on how the source code generated by the slicer can be incorporated into the thermal model. As a conclusion of the numerical results obtained, it can already be stated that the selected process parameters have a considerable influence on the temperature field, especially through the nozzle variation. Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-4474 SN - 978-3-9812696-7-2 N1 - Die Konferenzveröffentlichung erschien im Tagungsband zum 11. Landshuter Leichtbau-Colloquium „Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien“ (01./02. März 2023, Hochschule Landshut). Hrsg.: Otto Huber, Marc Bicker, Peter Patzelt. LC-Verlag/Hochschule Landshut, 2023, ISBN 978-3-9812696-7-2 SP - 106 EP - 123 PB - LC-Verlag, Hochschule Landshut CY - Landshut ER - TY - CHAP A1 - Whitmore, Lawrence A1 - Nischler, Anton A1 - Huber, Otto ED - Huber, Otto ED - Bicker, Marc ED - Patzelt, Peter T1 - Preparation of magnesium AZ31B for electron backscatter diffraction (EBSD) analysis T2 - Tagungsband 11. Landshuter Leichtbau-Colloquium: Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien N2 - A method for preparing magnesium alloy surfaces for metallographic study and electron backscatter diffraction (EBSD) analysis is presented. An alkaline polishing paste with a dispersion of alumina particles is used for more rapid preparation and a self-made low-power 3D printed vibratory polishing machine is used for final polishing. A final cleaning stage is developed to optimize surface quality after polishing, and an analysis is made on the effects of different solutions on surface corrosion. The method facilitates smaller groups and experimental projects on a small budget and, when combined with biodegradable filaments, can help labs meet sustainable development goals. The method and process for preparing samples are evaluated by examining the quality of magnesium AZ31B surfaces using optical and electron microscopy and EBSD orientation mapping. KW - Leichtbau KW - magnesium KW - surface KW - preparing KW - polishing Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-4469 SN - 978-3-9812696-7-2 N1 - Die Konferenzveröffentlichung erschien im Tagungsband zum 11. Landshuter Leichtbau-Colloquium „Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien“ (01./02. März 2023, Hochschule Landshut). Hrsg.: Otto Huber, Marc Bicker, Peter Patzelt. LC-Verlag/Hochschule Landshut, 2023, ISBN 978-3-9812696-7-2 SP - 86 EP - 105 PB - LC-Verlag, Hochschule Landshut CY - Landshut ER - TY - CHAP A1 - Rieser, Jasper A1 - Zimmermann, Markus ED - Huber, Otto ED - Bicker, Marc ED - Patzelt, Peter T1 - On the design of internal features for additive manufacturing T2 - Tagungsband 11. Landshuter Leichtbau-Colloquium: Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien N2 - Internal features are one of the biggest drivers for geometrical part complexity and pose a major challenge for manufacturing. A prominent example is the removal of material from a part interior as a simple though effective way to realize hollow sections, cavities or internal passages. While machining will most often be inapplicable, these features are in principle well within the feasible range of additive manufacturing (AM). However, careful design is essential to ensure a reasonable manufacturability since post-processing of internal features is possible only to a very limited extend. This paper reviews common applications of internal features and proposes a size-dependent classification helping to select appropriate design recommendations. The concept was applied to the design problem of a probe rake used for flow measurement where achieving a sufficiently large first natural frequency, integration of internal pressure channels and ensuring a good manufacturability were the main challenges. Starting from a solid conventional design, several new design variants were developed by introducing internal features of different size. The final design exhibits a large first natural frequency that was almost two times higher compared to a conventional rake design while the mass could be reduced by 30 %. A prototype was printed successfully from nickel-based super alloy on a selective laser melting system. KW - Leichtbau KW - additive manufacturing KW - design KW - internal features Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-4452 SN - 978-3-9812696-7-2 N1 - Die Konferenzveröffentlichung erschien im Tagungsband zum 11. Landshuter Leichtbau-Colloquium „Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien“ (01./02. März 2023, Hochschule Landshut). Hrsg.: Otto Huber, Marc Bicker, Peter Patzelt. LC-Verlag/Hochschule Landshut, 2023, ISBN 978-3-9812696-7-2 SP - 76 EP - 85 PB - LC-Verlag, Hochschule Landshut CY - Landshut ER - TY - CHAP A1 - Brandmayr, Felix A1 - Rapp, Helmut A1 - Leubecher, Dominik A1 - Höfer, Philipp ED - Huber, Otto ED - Bicker, Marc ED - Patzelt, Peter T1 - Contribution to the determination of the stiffness of ±45° FRP laminates T2 - Tagungsband 11. Landshuter Leichtbau-Colloquium: Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien N2 - Great discrepancies prevail between experimental investigations and conventional theoretical considerations of ±45° fibre reinforced plastics’ Young’s modulus. The examined multi-layer composites possess inhomogeneities on microscopic scale, most notably layers or bundles with locally increased fibre volume fraction. Therefore, an analytical approach is derived to characterise the composite’s stiffness on macroscopic scale correctly. Application to experimental data confirms the approach which is also of interest for additive manufacturing of long fibre reinforced composites. KW - stiffness KW - laminat KW - characterice KW - composite Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-4410 SN - 978-3-9812696-7-2 N1 - Die Konferenzveröffentlichung erschien im Tagungsband zum 11. Landshuter Leichtbau-Colloquium „Leichtbau - Werkstoffe, Konstruktionen, Fertigungstechnologien“ (01./02. März 2023, Hochschule Landshut). Hrsg.: Otto Huber, Marc Bicker, Peter Patzelt. LC-Verlag/Hochschule Landshut, 2023, ISBN 978-3-9812696-7-2 SP - 20 EP - 33 PB - LC-Verlag, Hochschule Landshut CY - Landshut ER - TY - JOUR A1 - Starflinger, Verena A1 - Martens, Maren T1 - Best Practices of Circular Business Models – Benefits and Challenges (not only) for German Start-ups JF - Research Notes on Data and Process Science N2 - Circular economy is becoming a buzzword in times where our planetary boundaries are increasingly being exhausted by the extensive extraction of global resources. Although the idea of reusing and recycling products or materials is quite simple and holds many advantages, the transformation towards circular business models imposes many hurdles. This paper gives an overview on the variety of circular business models, before it highlights opportunities and difficulties that companies may experience on their way towards them. It exemplary provides a view onto best practices from three German start-ups, with the aim of spreading awareness of key challenges and benefits. T3 - Research Notes on Data and Process Science - 5 KW - Kreislaufwirtschaft KW - Nachhaltigkeit KW - Geschäftsmodell Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-3918 SN - 2702-508X IS - 5 SP - 1 EP - 11 ER - TY - JOUR A1 - Türkmen, Derya A1 - Schmidtner, Markus A1 - Brueggemann, Ronja A1 - Timinger, Holger T1 - Analysis of inter-organisational project management in the automotive industry JF - Research Notes on Data and Process Science N2 - Collaboration between automotive manufacturers and tier suppliers across company boundaries involves a high degree of complexity. Collaboration is becoming increasingly important in this context, as the focus is on decentralized working through distributed project teams. This leads to new challenges regarding project management in the automotive supply chain. This paper examines the current state of cross-organizational project management in the automotive industry in the literature as well as in practice. T3 - Research Notes on Data and Process Science - 4 Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-3795 SP - 1 EP - 11 ER - TY - THES A1 - Brand, Lukas T1 - Extending and Evaluating CSPOT Type Constructors N2 - Serverless computing gained popularity as a programming model for cloud applications. It promises the elimination of operational tasks and infrastructure management, fast development times due to broad language support with simple APIs along with several other advantages such as cost optimization, high availability, and automatic scaling. Serverless runtimes offer an event-driven, decoupled, and modular architecture. "Internet of Things" (IoT) applications profit from the serverless programming model in that they are event-driven out-of-the-box and thus can be easily implemented. However, current serverless offerings lack support for distributed computation and unified abstractions from "end-to-end", i.e. the same programming model for IoT devices, edge devices as well as cloud data centers to implement IoT applications. CSPOT, a serverless platform of things is an ongoing research project that promises to solve the current limitations of existing IoT serverless solutions. This thesis focuses on a type and operation system that is part of Laminar, a runtime system built on top of CSPOT. Laminar provides a functional dataflow program representation for building distributed IoT applications. It improves the development experience for CSPOT applications and establishes the foundation for further programming abstractions and language implementations. KW - Serverless computing KW - Dataflow KW - CSPOT KW - type system KW - Cloud Computing KW - Internet der Dinge Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-3788 ER - TY - THES A1 - Veitl, Jakob T1 - Development of a laminable, cellulose-based Separator for Lithium-Ion Batteries N2 - Cellulose is a promising material for lithium-ion battery separator as it is sustainable, affordable, has excellent electrolyte wettability and is well applicable in lamination-based cell production. Lamination can accelerate the time-consuming stacking step in pouch cell assembly, reduce scrap rate and enhance battery performance, but relies on thermoplastic material on electrode/separator interfaces. In this work, different surface modification layers were applied to a cellulose separator via electrospinning technique and compared with regard to their applicability for lamination-based cell production. Processes have been developed to apply A) homogeneous fibers consisting of 4 different binder polymer types and b) layers of a fluorothermoplastic polymer (THV) with different morphologies. All layers were applied at the same low areal loading of 0.4 𝑔/𝑚2. All investigated polymer layers allowed to create mechanically stable interfaces without damaging the separator. The polymers were found to establish maximum adhesion at lamination temperatures that typically are about 10 K above their respective melting temperature. Highest adhesive forces above 15 𝑁/𝑚 were observed at lamination enabled by a low-melting fluoroelastomer (3M FPO 3850) at 120 °C. Evidence was found that many adhesion points well distributed over the surface cause higher adhesion than few large adhesion points, when applied at the same areal loading, but no clear statement can be made as to whether microfibers or microparticles lead to better adhesion. Regarding electrochemical performance, the cellulose separator was shown to be well suited for lithium-ion batteries. All 4 polymers used were found to be electrochemically stable in the applied voltage window and suitable for the use in NMC622 / graphite battery cells. Laminated cells with the developed interlayers showed improved (THV, FPO, PVDFS) or equal (PVDF-K) fast charging and discharging capability. Cells with THV coating performed best in C-rate tests, where their discharge capacity at 3 C rate was improved by 34.1% compared to non-laminated reference cells. Cells with the cellulose separator showed high capacity retention of 89.1% after 500 fast-charging cycles. The morphology of applied layers was not found to have a major influence on electrochemical performance, as long as the binder loading is kept at a moderate level and the deposited layer is porous and well distributed over the separator’s surface. N2 - Zellulose ist ein vielversprechendes Material als Separator von Lithium-Ionen-Batterien. Es ist nachhaltig, kostengünstig, ausgezeichnet mit Elektrolyt benetzbar und gut geeignet für den Einsatz von Lamination bei der Zellfertigung. Durch Lamination der Zellkomponenten kann der Stapelprozess bei der Pouchzellfertigung beschleunigt, die Ausschussrate reduziert und die Batterieleistung verbessert werden. Jedoch ist man dabei auf thermoplastisches Material an den Grenzflächen zwischen Elektroden und Separator angewiesen. In dieser Arbeit wurden mittels Elektrospinning verschiedene Oberflächenbeschichtungen auf einen Zellulose-Separator aufgebracht und hinsichtlich ihrer Anwendbarkeit für die laminationsbasierte Zellfertigung verglichen. Es wurden Prozesse entwickelt, um A) homogene Fasern aus 4 verschiedenen Binderpolymeren und B) Schichten unterschiedlicher Morphologie aus einem fluorthermoplastischen Polymer (THV) auf den Separator aufzubringen. Alle Schichten wurden mit der niedrigen Flächenbelastung von 0,4 𝑔/𝑚2 aufgebracht. Mit allen untersuchten Polymerschichten konnten mechanisch stabile Grenzflächen erzeugt werden, ohne dabei den Separator zu beschädigen. Es wurde festgestellt, dass die Polymere die optimale Haftung bei Laminationstemperaturen erzeugen, die typischerweise etwa 10 K über der jeweiligen Schmelztemperatur liegen. Die höchsten Haftkräfte von über 15 𝑁/𝑚 wurden bei der Lamination mit einem niedrig schmelzenden Fluorelastomer (3M FPO 3850) bei 120 °C beobachtet. Es wurde nachgewiesen, dass bei Auftrag mit gleicher Flächenbeladung viele gut über die Oberfläche verteilte Haftpunkte bessere Stabilität bewirken alswenige große Haftpunkte. Keine eindeutige Aussage konnte darüber getroffen werden, ob Mikrofasern oder Mikropartikel zu besserer Haftung führen. Hinsichtlich der elektrochemischen Leistungsfähigkeit erwies sich der Zellulose-Separator als sehr gut geeignet für den Einsatz in Lithium-Ionen-Batterien. Alle 4 verwendeten Polymere sind im angelegten Spannungsfenster elektrochemisch stabil und für den Einsatz in NMC622 /Graphit-Batteriezellen geeignet. Laminierte Zellen mit den entwickelten Zwischenschichten zeigten verbesserte (THV, FPO, PVDF-S) oder gleichwertige (PVDF-K) Schnelllade- und Entladefähigkeit. Die Entladekapazität von Zellen mit THV-Beschichtung lag bei 3 C um 34,1% über nicht-laminierten Referenzzellen. Zellen mit dem Zellulose- Separator zeigten nach 500 Schnellladezyklen eine hohe Restkapazität von 89,1%. Die Morphologie der aufgebrachten Schicht scheint die elektrochemische Leistung nicht wesentlich zu beeinflussen, sofern die Flächenbeladung der Zwischenschicht moderat ist und die aufgebrachte Schicht porös und gut über die Separatorfläche verteilt ist. KW - Lithium-Ionen-Akkumulator KW - Batterieseparator KW - Cellulose Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:860-opus4-3478 ER -