@inproceedings{27236, author = {{Schöppner, Volker and Fiebig, I. and Lakemeyer, P.}}, booktitle = {{70th Annual Assembly of the International Institute of Welding (IIW)}}, location = {{Shanghai (China)}}, title = {{{Opportunities in Welding of Fiber-Reinforced Thermoplastics for Different Weld Positions in Injection-Molded Parts}}}, year = {{2017}}, } @article{27237, author = {{Schöppner, Volker and Westhues, H.}}, issn = {{0023-5563}}, journal = {{Zeitschrift Kunststofftechnik / Journal of Plastics Technology}}, number = {{13. Jg. Heft 3}}, pages = {{196--211}}, title = {{{Phänomenorientierte Untersuchung der Feststoffförderzonen gleichläufiger Doppelschneckenextruder mithilfe der DEM-Simulation}}}, year = {{2017}}, } @inproceedings{27238, author = {{Schöppner, Volker and Fiebig, I.}}, booktitle = {{25. Fachtagung Technomer}}, location = {{Chemnitz (Deutschland)}}, title = {{{Potentiale zur Erhöhung der Schweißnahtfestigkeit faserverstärkter Thermoplaste}}}, year = {{2017}}, } @inproceedings{27240, author = {{Schöppner, Volker and Westhues, K.}}, booktitle = {{12. Würzburger Compoundiertage}}, location = {{Würzburg (Deutschland)}}, title = {{{Simulation von Doppelschneckenextrudern - Einblicke in das Gemeinschaftsforschungsprojekt SIGMA}}}, year = {{2017}}, } @inproceedings{27241, author = {{Schöppner, Volker and Lakemeyer, P.}}, booktitle = {{70th Annual Assembly of the International Institute of Welding (IIW)}}, location = {{Shanghai (China)}}, title = {{{Simulation-Based Investigations of the Temperature Influence during Laser Transmission Welding of Thermoplastics}}}, year = {{2017}}, } @inproceedings{27242, author = {{Schöppner, Volker and Lakemeyer, P. and Reinders, F.}}, booktitle = {{75th Annual Technical Conference of the Society of Plastics Engineers (ANTEC)}}, location = {{Anaheim (USA)}}, title = {{{Simulation-Based Investigations of the Temperature Influence during Laser Transmission Welding of Thermoplastics}}}, year = {{2017}}, } @inproceedings{22040, abstract = {{Fused Deposition Modeling (FDM) is used for prototypes, single-partproduction and small batch productions of thermoplastic components. This manufacturing technique has the huge benefit that no forming tool is needed. The knowledge about dimensional deviations which occur in the FDM process is necessary for calculating fits and for determining tolerances. A major challenge is the reproducibility of the dimensional accuracy of FDM parts and the reproducibility between different FDM machines. There are many influential factors on the dimensional accuracy in the FDM process for example geometric, material-specific or process-specific factors, which are considered in this paper. The influence of the part position on the build platform of a Stratasys Fortus 400mc is analyzed in terms of the achievable dimensional accuracy. For this purpose, the temperature distribution in the actively heated build chamber is investigated and possible correlations to the dimensional accuracy are identified. The reproducibility of one machine is examined by a multiple production of the test specimens. In addition, a comparison with three other FDM machines from Stratasys is made. Afterwards, the long-term reproducibility of the dimensional accuracy is verified to consider how environmental influences such as maintenance or modification of machine components affect the dimensional accuracy of the FDM process.}}, author = {{Knoop, F. and Lieneke, Tobias and Schöppner, Volker}}, booktitle = {{Rapid Tech - International Trade Show & Conference for Additive Manufacturing}}, pages = {{52--66}}, title = {{{Reproduzierbarkeit der Maßhaltigkeit im Fused Deposition Modeling}}}, doi = {{10.3139/9783446454606.004}}, year = {{2017}}, } @inproceedings{22042, abstract = {{Compared to conventional polymer processing technologies the material selection in the Fused Deposition Modelling (FDM) process is restricted. To expand the range of materials the requirements for the material properties and the semi-finished products (filaments) must be clarified. For this, a machine- and process-independent rating of the processability is necessary. The established standards for the tensile strength test apply to specimens with nearly isotropic mechanical properties. The FDM process generates anisotropic parts. The properties are mainly influenced by the machine quality and the data processing. It is not possible to test a material for FDM independently of the machine and the data processing. In this paper, machine and process specific influences are investigated. Considering these influences, a custom-built specimen is created to test the tensile strength of the welding seams for polyamide 6. This procedure allows a machine- and process-independent rating of the processability in terms of tensile strength for different materials.}}, author = {{Schumacher, C. and Schöppner, Volker and Guntermann, J.}}, booktitle = {{28th Annual International Solid Freeform Fabrication Symposium}}, pages = {{470--484}}, title = {{{Considering machine- and process-specific influences to create custom-built specimens for the Fused Deposition Modeling process}}}, doi = {{http://utw10945.utweb.utexas.edu/sites/default/files/2017/Manuscripts/ConsideringMachineandProcessSpecificInfluenc.pdf}}, volume = {{28}}, year = {{2017}}, } @inproceedings{22045, abstract = {{A widely used Additive Manufacturing (AM) technology is Fused Deposition Modeling (FDM) to create prototypes and end-use parts with close-to-production thermoplastics. For their use as a final product, it is necessary that additively manufactured parts strictly adhere to the geometrical requirements of the technical drawing. In this paper, the holes and cylinders of the cylindrical elements are investigated in terms of achievable geometrical accuracy. For this purpose, different test specimens that allow a measurement of inner and outer diameters from 3 to 80 mm were designed. All specimens were measured with a coordinate measuring machine (CMM) to evaluate deviations from the nominal dimension and form deviations. The measuring method includes a scanning of the surface to record the course of dimensional deviations over the diameter. Thus, it was possible to visualize how deviations on cylindrical elements manufactured in FDM occur. In order to counteract these deviations and to improve the dimensional accuracy, different shrink factors and filling patterns were investigated. Consequently, an improvement of the dimensional accuracy was achieved.}}, author = {{Knoop, F. and Schöppner, Volker}}, booktitle = {{28th Annual International Solid Freeform Fabrication Symposium}}, pages = {{2757--2776}}, title = {{{Geometrical Accuracy of Holes and Cylinders Manufactured with Fused Deposition Modeling}}}, doi = {{http://utw10945.utweb.utexas.edu/sites/default/files/2017/Manuscripts/GeometricalAccuracyofHolesandCylindersManufa.pdf}}, volume = {{28}}, year = {{2017}}, } @article{22049, abstract = {{Um die Materialauswahl für den FDM-Prozess zu steigern, sollten die durch den FDM-Prozess an das Material gestellten Anforderungen bekannt sein. Dazu ist eine von der Maschine und der individuellen Datenaufbereitung möglichst unabhängige Bewertung der FDM-Verarbeitungseignung wünschenswert. In diesem Artikel werden eine Prüfmethode und ein dazu entwickelter Probekörper vorgestellt, mit dem die Schweißnahtfestigkeit verschiedener Polyamid 6 Typen im FDM-Prozess ermittelt und verglichen wird.}}, author = {{Schöppner, Volker and Schumacher, C. and Guntermann, J.}}, isbn = {{1618-8357}}, journal = {{Jahresmagazin Kunststofftechnik}}, number = {{1}}, pages = {{108--114}}, publisher = {{Institut für Wissenschaftliche Veröffentlichungen}}, title = {{{Beurteilung der Schweißnahtfestigkeiten verschiedener Kunststoffe im FDM-Prozess}}}, volume = {{1}}, year = {{2017}}, } @article{22033, abstract = {{The mechanical characterization of fused deposition modeling (FDM) parts is mostly done by static tests. In many applications, parts are also dynamically loaded. Here, fatigue tests can help to identify the expected lifetime of a part. This article discusses the fatigue behavior of FDM specimens manufactured with Ultem 9085. For this, tensile bars are manufactured according to ASTM D638 in different build orientations. Tests are performed in a range of pulsating tensile stresses, and S-N curves are documented for different build orientations. For higher loads, the FDM anisotropy characterizes the lifetime of used specimens, which is similar to static tensile bars. For lower loads, including a higher number of cycles to failure, S-N curves of different build orientations converge. In further tests, tensile bars were chemically smoothed with chloroform vapor. Chemical smoothing reduces surface roughness and increases tensile strength of specimens in the upright build direction. Fatigue tests of chemically treated specimens show no significant lifetime increase.}}, author = {{Fischer, M. and Schöppner, Volker}}, journal = {{JOM: The Journal of The Minerals. Metals & Materials Society (TMS)}}, pages = {{563--568}}, publisher = {{Springer Verlag}}, title = {{{Fatigue Behavior of FDM Parts Manufactured with Ultem 9085}}}, doi = {{10.1007/s11837-016-2197-2}}, year = {{2017}}, } @inproceedings{22023, abstract = {{Fused Deposition Modeling (FDM) is an Additive Manufacturing (AM) technology which is used for prototypes, single-part-production and also small batch productions. For use as a final product, it is important that the parts have good mechanical properties, a high dimensional accuracy and smooth surfaces. The knowledge of the mechanical properties is very important for the design engineer when it comes to the component design. In this paper, investigations were conducted with the polymer ABS-M30 from Stratasys Inc. To achieve a quality improvement of FDM parts, various toolpath parameters and orientations were used. Within the mechanical properties, the tensile, flexural and impact strength were evaluated. Furthermore, the tensile strength of FDM parts is compared to injection molded specimens. With optimized parameters, an increase of the tensile strength by up to 28 % and a doubling of the impact strength were possible.}}, author = {{Knoop, F. and Kloke, A. and Schöppner, Volker}}, booktitle = {{32nd International Conference of the Polymer Processing Society}}, publisher = {{American Institute of Physics}}, title = {{{Quality Improvement of FDM Parts by Parameter Optimization }}}, doi = {{10.1063/1.5016790}}, volume = {{32}}, year = {{2017}}, } @inproceedings{27201, author = {{Schöppner, Volker and Schadomsky, Michael and Walter, J.}}, booktitle = {{25. Fachtagung Technomer}}, location = {{Chemnitz (Deutschland)}}, title = {{{Bestimmung der Mischgüte bei Kautschukstiftextrudern auf Basis experimenteller und simulativer Methoden}}}, year = {{2017}}, } @inproceedings{27220, author = {{Schöppner, Volker and Lakemeyer, P. and Wübbeke, Andrea and Geißler, S. and Schmidt, M.}}, booktitle = {{70th Annual Assembly of the International Institute of Welding (IIW)}}, location = {{Shanghai (China)}}, title = {{{Investigation of Residual Stress in Laser Transmission Welding of Polypropylene}}}, year = {{2017}}, } @inproceedings{27245, author = {{Schöppner, Volker and Westhues, K. and Westhues, T}}, booktitle = {{32nd International Conference of the Polymer Processing Society (PPS)}}, location = {{Lyon (Frankreich)}}, title = {{{A New Sample Preparation Method to Investigate Melting Phenomena within a Partly Filled Melting Zone Of Co-Rotating Twin Screw Extruders}}}, year = {{2016}}, } @article{27248, author = {{Schöppner, Volker and Brockhaus, S. and Penner, C. and Möckel, J.}}, issn = {{0176-1625}}, journal = {{GAK Gummi Fasern Kunststoffe}}, number = {{69. Jg. Heft 7}}, pages = {{410--413}}, title = {{{Auswirkungen von Betriebsparametern in der Heißluftvulkanisation}}}, year = {{2016}}, } @article{27249, author = {{Schöppner, Volker and Littek, S. and Döring, Artjom and Kuckling, Dirk}}, journal = {{Zeitschrift Kunststofftechnik / Journal of Plastics Technology}}, pages = {{18}}, title = {{{Berechnung des Materialabbaus von PP und PS in der Plastifiziereinheit Teil 1: Belastung und Materialmodellierung}}}, year = {{2016}}, } @inproceedings{27258, author = {{Schöppner, Volker and Pohl, M.}}, booktitle = {{32nd International Conference of the Polymer Processing Society (PPS)}}, location = {{Lyon (Frankreich)}}, title = {{{First Insight into the High Speed Extrusion of Polycarbonate}}}, year = {{2016}}, } @article{27261, author = {{Schöppner, Volker and Fiebig, I.}}, issn = {{1687-9430}}, journal = {{International Journal of Polymer Science}}, number = {{Onlineausgabe}}, title = {{{Influence of the Initial Fiber Orientation on the Weld Strength in Welding of Glass Fiber Reinforced Thermoplastics}}}, year = {{2016}}, } @inproceedings{27262, author = {{Schöppner, Volker and Fiebig, I.}}, booktitle = {{69th Annual Assembly of the International Institute of Welding (IIW)}}, location = {{Melbourne (Australien)}}, title = {{{Investigation on Factors Influencing Fiber Orientation in Welding of Fiber Reinforced Thermoplastics}}}, year = {{2016}}, }