@article{23844, author = {{Bürenhaus, Franziska Isabelle and Moritzer, Elmar and Hirsch, André}}, issn = {{0043-2288}}, journal = {{Welding in the World}}, pages = {{1819--1832}}, title = {{{Adhesive bonding of FDM-manufactured parts made of ULTEM 9085 considering surface treatment, surface structure, and joint design}}}, doi = {{10.1007/s40194-019-00810-4}}, year = {{2019}}, } @misc{23845, author = {{Moritzer, Elmar and Bürenhaus, Franziska Isabelle and Hirsch, André}}, booktitle = {{Kunststoffe internationl}}, issn = {{1862-4243}}, number = {{2}}, pages = {{48--52}}, title = {{{Advancing into New Dimensions}}}, volume = {{109}}, year = {{2019}}, } @misc{23850, author = {{Moritzer, Elmar and Bürenhaus, Franziska Isabelle and Hirsch, André}}, booktitle = {{Kunststoffe}}, number = {{2}}, pages = {{68--72}}, title = {{{Vorstoß in neue Dimensionen}}}, volume = {{109}}, year = {{2019}}, } @inproceedings{23879, author = {{Albrecht, Mirko and Gehde, Michael and Bialaschik, Max and Schöppner, Volker}}, isbn = {{978-3-939382-14-0 }}, location = {{Chemnitz}}, title = {{{Einfluss des Werkzeugdesignes auf das Erwärmverhalten beim Warmgasschweißen}}}, year = {{2019}}, } @article{20890, author = {{Engelkemeier, Katja and Lindner, Jörg K N and Bürger, Julius and Vaupel, Kathrin and Hartmann, Marc and Tiemann, Michael and Hoyer, Kay-Peter and Schaper, Mirko}}, issn = {{0957-4484}}, journal = {{Nanotechnology}}, title = {{{Nano-architectural complexity of zinc oxide nanowall hollow microspheres and their structural properties}}}, doi = {{10.1088/1361-6528/ab55bc}}, year = {{2019}}, } @inproceedings{22022, abstract = {{Due to the great popularity of the Fused Deposition Modeling (FDM) process, the material market is growing. In particular, processing of high-temperature materials such as PEEK is demanding. The aim of the investigations is to test different PEEK materials regarding their processability in the FDM process. An unreinforced PEEK, a thermally conductive PEEK as well as a carbon fiber reinforced PEEK are investigated. The processability is assessed with the help of the weld seam strength. The assessment of the weld seam strength is carried out by building tests. For this purpose, a special method developed at the DMRC is used. In addition, a welding width factor between the strands deposited on each other is calculated and compared. Finally, a welding factor is determined to enable the comparison between the different materials. With this procedure, the influence of varying nozzle and build chamber temperatures on the achievable weld seam strengths is evaluated.}}, author = {{Moritzer, Elmar and Wächter, Julian and Elsner, M.}}, booktitle = {{30th Annual International Solid Freeform Fabrication Symposium}}, pages = {{856--863}}, title = {{{Investigation of the Processability of Different PEEK Materials in the FDM Process with Regard to the Weld Seam Strength}}}, doi = {{http://utw10945.utweb.utexas.edu/sites/default/files/2019/074%20Investigation%20of%20The%20Processability%20of%20Different%20P.pdf}}, volume = {{30}}, year = {{2019}}, } @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}}, }