@inproceedings{16794, author = {{Striewe, Jan André and Thomas, Robert and Fischer, Fabian and Wiens, Timo and Tröster, Thomas}}, location = {{Neu-Ulm}}, publisher = {{DGM-Inventum GmbH }}, title = {{{Energieabsorptions- und Versagensverhalten eines automobilen Seitenschwellers mit lokaler Verstärkung aus kohlenstofffaserverstärktem Kunststoff nach Alterung}}}, year = {{2019}}, } @misc{16825, author = {{Ahlers, Dominik and Tröster, Thomas}}, publisher = {{EuroPM}}, title = {{{Performance Parameters and HIP Routes for additively manufactured titanium alloy Ti6Al4V}}}, year = {{2019}}, } @inproceedings{16826, author = {{Camberg, Alan Adam and Hielscher, Christian}}, booktitle = {{Aachen Body Engineering Days 2019}}, location = {{Aachen}}, title = {{{A holistic approach to the lightweight design of tailored structural components using the example of a hybrid A-pillar}}}, year = {{2019}}, } @inproceedings{16827, author = {{Camberg, Alan Adam and Tröster, Thomas}}, booktitle = {{26. Sächsische Fachtagung Umformtechnik}}, location = {{Dresden}}, title = {{{Challenges in fracture modeling under non-isothermal forming conditions using the example of a new forming process for aluminum blanks}}}, year = {{2019}}, } @inproceedings{16831, author = {{Tinkloh, Steffen Rainer and Wu, Tao and Tröster, Thomas and Niendorf, Thomas}}, location = {{Wuhan}}, title = {{{A micromechanical based finite element simulation of process induced residual stresses in metal-CFRP-hybrid structures}}}, year = {{2019}}, } @article{15875, author = {{Camberg, Alan Adam and Tröster, Thomas and Bohner, F. and Tölle, J.}}, issn = {{1757-899X}}, journal = {{IOP Conference Series: Materials Science and Engineering}}, pages = {{012057}}, title = {{{Predicting plasticity and fracture of severe pre-strained EN AW-5182 by Yld2000 yield locus and Hosford-Coulomb fracture model in sheet forming applications}}}, doi = {{10.1088/1757-899X/651/1/012057}}, volume = {{651}}, year = {{2019}}, } @article{15950, author = {{Akbulut Irmak, Emine Fulya and Tröster, Thomas}}, issn = {{2452-3216}}, journal = {{Procedia Structural Integrity}}, pages = {{190--197}}, title = {{{Fracture prediction of additively manufactured AlSi10Mg materials}}}, doi = {{10.1016/j.prostr.2019.12.101}}, year = {{2019}}, } @inproceedings{15976, author = {{Akbulut Irmak, Emine Fulya and Hanses, Julius and Schweizer, Swetlana and Tröster, Thomas}}, location = {{Koblenz}}, title = {{{Modeling the Energy Absorption Characteristics of Wood Crash Elements}}}, year = {{2019}}, } @techreport{16029, author = {{Marten, Thorsten and Tröster, Thomas}}, publisher = {{Forschungsvereinigung Stahlanwendung e.V. im Stahl Zentrum, P920, Verlag und Vertriebsgesellschaft mbH}}, title = {{{Einsatz neuartiger Stähle und Generierung gradierter Leichtbaustrukturen im Presshärteprozess}}}, year = {{2019}}, } @inproceedings{16032, author = {{Stallmeister, Tim and Chalicheemalapalli Jayasankar, Deviprasad and Wang, Z. and Tröster, Thomas}}, isbn = {{9781925627220}}, location = {{Melbourne }}, title = {{{Self-sealing tool concept for RTM-processes}}}, year = {{2019}}, } @inproceedings{16033, author = {{Stallmeister, Tim and Chalicheemalapalli Jayasankar, Deviprasad and Wang, Z. and Tröster, Thomas}}, location = {{Neu-Ulm}}, title = {{{Selbstabdichtendes Werkzeugkonzept für RTM-Prozesse}}}, year = {{2019}}, } @article{22047, abstract = {{Plastic freeforming (PF) is an additive-manufacturing process for producing three-dimensional plastic parts based on 3D CAD data by applying plastic droplets in layers. This process is used to produce customer-specific and complex geometries (prototypes and small series) on organic sheets. A comparable serial process is the injection of a second component onto organic sheets by injection molding. A sufficient bond between the PF structure and the organic sheets is of particular importance for each application. If this is not guaranteed, the composite system cannot withstand the mechanical load and fails. The force exerted on the system can no longer be transmitted between the PF structure and the organic sheet. The organic sheet is made of glass fiber-reinforced polypropylene (PP). The connection between the organic sheet and the PF structure is achieved by welding the molten polymer droplets and the surface of the organic sheet. The PF structures are made of PP to ensure sufficient compatibility with regard to the weldability of the components. The processing of PP in the PF process is a challenge because PP is a semicrystalline material. The shrinkage of semi-crystalline materials is significantly higher compared to amorphous materials. Due to the layered structure of the components, the shrinkage of the individual layers results in undesired warpage. The adhesive strength between the organic sheet and the PF structure is investigated by determining the bending strength in the 3-point bending test. The investigations include an optimization of the process parameters to maximize the adhesive strength. The experimental investigations show that an increase of the nozzle and build chamber temperature leads to a higher adhesive strength. In further investigations, the temperature of the nozzle shows no significant influence on the surface temperature despite the expected heat radiation. The surface temperature is almost only dependent on the temperature of the build chamber.}}, author = {{Moritzer, Elmar and Hirsch, André and Heim, H.P. and Cherif, C. and Truemper, W.}}, journal = {{Welding in the World}}, pages = {{867--873}}, publisher = {{Springer}}, title = {{{Plastic droplet welding: bond strength between plastic freeforming structures and continuous fiber-reinforced thermoplastic composites}}}, doi = {{10.1007/s40194-019-00714-3}}, volume = {{63}}, year = {{2019}}, } @inproceedings{22028, abstract = {{The mechanical properties of thin-walled plastic components are limited. One approach to improve the strength or stiffness of these components is to reinforce the thin-walled areas with an individually adapted Fused Deposition Modeling structure. Fused Deposition Modeling (FDM) is one of the most commonly used additive manufacturing processes. This process is characterized by the deposition of a fused, thermoplastic filament. Depending on the form of the reinforcement structure, the resulting hybrid structure should show higher strength or stiffness. The objective of the project is to determine constructive design and process guidelines for FDM structures. The FDM structure is to be used as a partial reinforcement for lightweight components and be adapted to the respective load conditions. Because of the lightweight application, the FDM structure should also have the lowest possible weight. The optimization of the FDM parts for different load cases is realized by adapting the design parameters. These parameters influence the layer generation and therefore also the inner structure of the FDM parts. In preliminary studies, the manufacturing restrictions of the FDM process are defined. The specimens are manufactured based on the Design of Experiments. To determine the static strength properties, different tests (tensile, compression, flexural, torsion and impact) are carried out. The investigations show that the filling strategy affects the mechanical properties. As a result of the investigations, design and process guidelines for the FDM structures are established according to the load conditions.}}, author = {{Moritzer, Elmar and Hirsch, André and Bürenhaus, Franziska Isabelle}}, booktitle = {{AIP Conference Proceedings}}, number = {{1}}, publisher = {{AIP Publishing}}, title = {{{Development and Modeling of Design and Process Guidelines for FDM Structures for the Partial Reinforcement of Hybrid Structures}}}, doi = {{10.1063/1.5088314}}, volume = {{2065}}, year = {{2019}}, } @inproceedings{22027, abstract = {{Additive manufacturing processes, like the Fused Deposition Modeling (FDM) process, do not need product-specific tools and create parts directly from the CAD data. In the FDM process, the semi-finished product, a wire of a thermoplastic polymer, is melted and forced through a nozzle. The continuous positioning of this nozzle allows the polymer to weld together strand by strand and layer by layer to produce a component. Because no mold is used in the FDM process, no holding pressure can be generated as in injection molding processes, in which the holding pressure is used to minimize the shrinkage and warpage of the part. In the FDM process, the part is generated in an ambient pressure environment. Each strand cools down and shrinks separately. This causes residual stresses in the part that can lead to major warpage and a complete stoppage of the process. This is the main reason why the material selection in the FDM process is restricted in comparison to conventional polymer processing technologies. In this paper, the warpage of different polymers is quantified as a criterion for evaluating the processability of polymers in the FDM process. Due to the process principle, the part properties in the FDM process are mainly influenced by the machine quality and the data processing, so that it is difficult to test a material for FDM independently of the machine and the data processing. Considering these influences, a custom-built specimen is created to test and quantify the warpage of different types of blended and reinforced polyamide 6. Considering the experimentally investigated warpage, the materials can be evaluated and the warpage can be related to the shrinkage investigated in pvT measurements. This procedure allows the machine- and process-independent rating of the processability in terms of warpage for different materials. Alongside other criteria, this is a necessary step to develop new materials with good processability in the FDM process.}}, author = {{Schöppner, Volker and Schumacher, C. and Fels, C.}}, booktitle = {{AIP Conference Proceedings}}, publisher = {{AIP Publishing}}, title = {{{A Method to Evaluate the Process-Specific Warpage for Different Polymers in the FDM Process}}}, doi = {{10.1063/1.5088315}}, year = {{2019}}, } @book{22026, abstract = {{Das Fused Deposition Modeling (FDM) ist ein etabliertes additives Fertigungsverfahren zur Her-stellung von thermoplastischen Kunststoffbauteilen. In dem vorliegenden Beitrag sind FDM-Verstärkungsstrukturen aus dem Material Ultem 9085 dynamischen Langzeituntersuchungen un-terzogen worden. Dabei wurde die innere Struktur der Probekörper über eine Parametervariation verändert, sodass anschließend die signifikanten Einflussfaktoren auf die Langzeitfestigkeit un-ter dynamischer Belastung identifiziert und analysiert werden konnten. Mit dieser Vorgehens-weise sollte gleichzeitig eine Optimierung der FDM-Verstärkungsstrukturen hinsichtlich der dy-namischen Langzeiteigenschaften bei Biege- und Druckbelastungen vorgenommen werden. Des Weiteren sind anhand der Probekörper die auftretenden Bruch- und Rissausbreitungsmechanis-men analysiert worden. Anhand der ermittelten Wöhlerkurven kann die Lebensdauer unter dy-namischer Belastung abgeschätzt werden. Außerdem zeigen die Untersuchungen, dass Fehlstel-len durch eine hohe Strangbreite und Überfüllungen im Bauteil für Schwachstellen in den FDM-Verstärkungsstrukturen sorgen, an denen Risse bei Druckbelastung entstanden sind und sich dadurch schneller ausbreiten konnten.}}, author = {{Moritzer, Elmar and Hirsch, André and Paulus, S.}}, isbn = {{978-3-658-27411-5}}, pages = {{185--198}}, publisher = {{Springer Vieweg}}, title = {{{Rissausbreitungsmechanismen in FDM-Verstärkungsstrukturen unter dynamischer Beanspruchung}}}, doi = {{10.1007/978-3-658-27412-2}}, year = {{2019}}, } @inproceedings{22041, abstract = {{The Arburg Plastic Freeforming (APF) is an additive manufacturing process that allows three-dimensional, thermoplastic components to be produced in layer by layer. The components are generated by depositing fine, molten plastic droplets. One of the main advantages of the APF process is the open machine control. Thus, the process parameters can be adapted and optimized for the individual applications. The optimization is carried out on the basis of a variation of the process parameters using a statistical design of experiments. Relevant process parameters are the layer thickness, the form factor, the raster and delta angle as well as the overlap between the contour and the filling of a layer. In addition, the nozzle and build chamber temperatures are varied. Using this procedure, the effects of the influencing parameters on the mechanical properties and the interactions between the influencing parameters are analyzed and converted into mathematical models. On the basis of the results and the models, guidelines will be developed to assist the user of APF technology in the systematic process configuration for their own applications. The material used is ABS, one of the most frequently used amorphous thermoplastics in additive manufacturing. The mechanical properties are determined on the basis of tensile tests and the characteristic values tensile strength, elongation at break and Young's modulus. The results should show the performance of the APF technology in regard to the mechanical properties.}}, author = {{Moritzer, Elmar and Hirsch, André and Hecker, Felix}}, booktitle = {{30th Annual International Solid Freeform Fabrication Symposium}}, pages = {{705--714}}, title = {{{Process Parameter Optimization to Improve the Mechanical Properties of Arburg Plastic Freeformed Components}}}, doi = {{http://dx.doi.org/10.26153/tsw/17308}}, volume = {{30}}, year = {{2019}}, } @phdthesis{37602, author = {{Gehring, Andreas}}, title = {{{Untersuchungen zum energetischen Verhalten von Kunststoffverarbeitungsprozessen auch im Rahmen von Energiemanagementsystemen}}}, year = {{2019}}, } @phdthesis{37619, author = {{Westhues, Kim Jacqueline}}, title = {{{Entwicklung eines Modells zur Berechnung der initialen Aufschmelzvorgänge in gleichläufigen Doppelschneckenextrudern}}}, year = {{2019}}, } @article{19122, author = {{Penner, Eduard and Caylak, Ismail and Dridger, Alex and Mahnken, Rolf}}, issn = {{2325-3444}}, journal = {{Mathematics and Mechanics of Complex Systems}}, pages = {{99--129}}, title = {{{A polynomial chaos expanded hybrid fuzzy-stochastic model for transversely fiber reinforced plastics}}}, doi = {{10.2140/memocs.2019.7.99}}, year = {{2019}}, } @article{19120, author = {{Caylak, Ismail and Penner, Eduard and Mahnken, Rolf}}, issn = {{1617-7061}}, journal = {{PAMM}}, title = {{{A fuzzy uncertainty model for analytical and numerical homogenization of transversely fiber reinforced plastics}}}, doi = {{10.1002/pamm.201900356}}, year = {{2019}}, }