@article{21704, abstract = {{Even in times where additive manufacturing has a peak in media and industry interest, only few companies have already implemented this technology. Many companies struggle with the use of AM even if they have already identified the benefits of this technology for their business. Additional knowledge along the whole product development chain is necessary to succeed in implementing this technology. As all other production technologies, AM has certain strength and weaknesses which affect the suitable part candidates. Redesign or manufacturing approaches of unsuited part candidates are no very likely to be successful. In general, aspects like design rules need to be known along the product development process in order to achieve technology-based benefits during production and post-processing resulting in economic success. This paper will present a holistic approach which will assist the designer during product development and manufacturing based on an example part from the space industry. Then methodology starts with an appropriate part selection as a key parameter for the product development process. Based on the promising part candidates, deductions for the further product development process will be described. This includes approaches for functional integration as well as a methodology for the compilation of part requirements. Those are utilized for a black box methodology, ensuring a time-efficient redesign based on FEA optimization and design rules for additive manufacturing. Best practices for integrating (or in the best case avoiding) traditional technologies are discussed. Based on this, the development of industrialization and test and verification plans for production are shown. This includes the marking of parts for traceability during the whole product lifecycle for quality reasons as well as for product protection. Furthermore, production and production planning are discussed. This is followed by post-processing and testing procedures of the part. The paper will close with a detailed economic view on the topic and some deductions regarding the changes in the supply chain. The methodology itself is discussed and explained on a real sample metal part. The general methodology is discussed on the basis of the space industry but is subject to be adapted to other industries.}}, author = {{Reiher, T. and Lindemann, C. and Jahnke, U. and Deppe, G. and Koch, R.}}, isbn = {{2363-9520}}, journal = {{Progress in Additive Manufacturing}}, pages = {{43--55}}, publisher = {{Springer}}, title = {{{Holistic approach for industrializing AM technology - from part selection to test and verification}}}, doi = {{https://doi.org/10.1007/s40964-017-0018-y}}, volume = {{2}}, 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}}, } @inproceedings{6559, author = {{Claes, Leander and Zeipert, Henning and Koppa, Peter and Tröster, Thomas and Henning, Bernd}}, booktitle = {{Proceedings of Meetings on Acoustics}}, pages = {{030004}}, title = {{{Additively manufactured acoustic diffuser structures for ultrasonic measurement applications}}}, doi = {{10.1121/2.0000688}}, year = {{2017}}, } @inproceedings{16063, author = {{Ahlers, Dominik and Tröster, Thomas}}, location = {{Austin, Texas, USA}}, title = {{{Approve of porostiy for increasing process speed in the laser melting process of Ti6Al4V}}}, year = {{2017}}, } @inproceedings{16074, author = {{Ahlers, Dominik and Tröster, Thomas}}, location = {{Erfurt}}, title = {{{Materialkombinationen in der additive Fertigung}}}, year = {{2017}}, } @inproceedings{16075, author = {{Ahlers, Dominik and Tröster, Thomas}}, location = {{Nördlingen}}, title = {{{Aspekte der Produktentwicklung in der additiven Fertigung}}}, year = {{2017}}, } @article{22038, abstract = {{Micro Physiological Systems (MPS), also known as Multi-Organ-Chip, Organ-on-a-Chip, or Body-on-a-Chip, are advanced microfluidic systems that allow the cultivation of different types of cells and tissue in just one common circuit. Furthermore, they thus can also adjust the interaction of these different tissues. Perspectival MPS will replace animal testing. For fast and flexible manufacturing and marking of MPS, a concept for a universal micromachining platform has been developed which provides the following latest key technologies: laser micro cutting of polymer foils, laser micro- and sub-micro-structuring of polymer foils, 3D printing of polymer components as well as optical inspection and online process control. The combination of different laser sources, processing optics, inspection systems, and print heads on multiple axes allows the change and exactly positioning to the workpiece during the process. Therewith, the realization of MPS including 3D printed components as well as direct laser interference patterned surfaces for well-defined cell adhesion and product protection is possible. Additional basic technologies for the generation of periodical line-like structures at polycarbonate foils using special Direct Laser Interference Patterning (DLIP) optics as well as for the 3D printing of fluid-tight cell culture reservoirs made of Acrylonitrile Butadiene Styrene directly onto polycarbonate microfluidics were established. A first prototype of the universal micromachining platform combining different lasers with Direct Laser Writing and DLIP is shown. With this laser micro cutting as well as laser micro-structuring of polycarbonate (PC) foils and therewith functionalization for MPS application could be successfully demonstrated.}}, author = {{Moritzer, Elmar and Hirsch, André and Günther, K. and Sonntag, F. and Klotzbach, U. and Lasagni, A.F.}}, journal = {{Micromachines}}, number = {{246}}, publisher = {{MDPI}}, title = {{{Universal Micromachining Platform and Basic Technologies for the Manufacture and Marking of Microphysiological Systems}}}, doi = {{10.3390/mi8080246}}, volume = {{8}}, 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{16066, author = {{Ahlers, Dominik and Koppa, Peter and Hengsbach, Florian and Gloetter, P. and Altmann, A. and Schaper, Mirko and Tröster, Thomas}}, booktitle = {{Proceedings of the 28th Annual InternationalSolid Freeform Fabrication Symposium – An Additive Manufacturing Conference}}, location = {{Austin, Texas, USA}}, title = {{{Increasing process speed in the laser melting process of Ti6Al4V and the reduction of pores during hot isostatic pressing}}}, year = {{2017}}, } @phdthesis{24774, abstract = {{In dieser Arbeit wurde ein Prozessverständnis für das FDM-Verfahren hinsichtlich der Verarbeitung des Materials Ultem*9085 aufgebaut. Es wurde der Einfluss des Materials, des Prozesses und der Maschine auf die resultierende Bauteilqualität untersucht. Die Materialqualität unterschiedlicher Chargen zeigt, dass Feuchtigkeit im Material die Strangablage beeinflusst. Die Analyse der Prozessparameter, die anhand der Kurzzeitfestigkeiten analysiert wurden, zeigt einen starken Einfluss der Aufbauorientierung. Mittels einer Parameteroptimierung können ferner gleiche Festigkeitswerte wie aus dem Spritzgießprozess erreicht werden. Bei der Untersuchung der Langzeitfestigkeiten wurde festgestellt, dass sich die Festigkeitswerte bei unterschiedlichen Umgebungsbedingungen nicht ändern. Die Untersuchung einiger Anlagenkomponenten auf die resultierende Oberflächengüte, Geometriegenauigkeit und Festigkeitseigenschaften kann den Einfluss von u. a. der Bauraum- sowie der Düsentemperaturen auf die Bauteilqualität zeigen. Zuletzt wurde die Möglichkeit einer Leichtbauanwendung anhand von Sandwich-Prüfkörpern untersucht. Hierbei beeinflussen sowohl die verfahrensunabhängige Mechanik als auch die verfahrensspezifischen Effekte die Festigkeitswerte.}}, author = {{Kloke, Agnes}}, isbn = {{978-3-8440-4489-8}}, pages = {{172}}, publisher = {{Shaker Verlag}}, title = {{{Untersuchung der Werkstoff-, Prozess- und Bauteileigenschaften beim Fused Deposition Modeling Verfahren}}}, volume = {{4}}, year = {{2016}}, } @phdthesis{26901, abstract = {{In der vorliegenden Arbeit wurden die mikrostrukturellen Eigenschaften und das dadurch resultierende mechanische Verhalten der im SLM-Verfahren (Selective Laser Melting) hergestellten Nickelbasis-Superlegierung Inconel 939 untersucht und einer Inconel 939 Gusslegierung gegenübergestellt. Die monotonen und mikrostrukturellen Untersuchungsergebnisse zeigen eine eindeutige Abhängigkeit der Herstellungsrichtung und deutliche Unterschiede zur Gusslegierung, insbesondere in der Mikrostruktur. Dehnungsgeregelte isotherme und thermomechanische Ermüdungsversuche in Kombination mit der Methode der digitalen Bildkorrelation (DIC) beschreiben das mechanische Verhalten sowie die kritischen Bereiche im Gefüge. Ob beim SLM- oder Gusswerkstoff eine höhere Lebensdauer bei der isothermen Ermüdung erreicht wird, ist von der Höhe der Beanspruchung abhängig. Im ausscheidungsgehärteten Zustand besitzt das SLM-Material bei niedrigen Belastungen und Temperaturen von Raumtemperatur bis 750 °C eine höhere Lebensdauer und zeigt somit ein besseres Ermüdungsverhalten als der Gusswerkstoff. Bei höheren Dehnungsamplituden werden vorhandene Poren aktiviert und ein schnelles Versagen tritt ein. Mit geeigneten HIP-Parametern konnte die Porosität allerdings deutlich reduziert werden.}}, author = {{Kanagarajah, Pirabagini}}, isbn = {{978-3-8440-4796-7}}, keywords = {{Nickelbasis-Superlegierung, Inconel 939, Laserschmelzverfahren, SLM, Ermüdung, Mikrostruktur}}, pages = {{182}}, title = {{{Ermüdungsverhalten und mikrostrukturelle Charakterisierung der im Laserschmelzverfahren hergestellten Nickelbasis-Superlegierung Inconel 939}}}, volume = {{6}}, year = {{2016}}, } @techreport{23737, author = {{Lammers, Stefan and Quattrone, Francesco and Mrozek, Rafael}}, publisher = {{Forschungsvereinigung Antriebstechnik e.V.}}, title = {{{Machbarkeitsstudie 3D Druck Elektromotoren}}}, volume = {{Nr. 1189}}, year = {{2016}}, } @inproceedings{22107, abstract = {{Die Zielsetzung beim Radfahren ist das Leistungspotential des Fahrers vollständig auszunutzen. Dabei muss das Fahrrad optimal an die Körpermaße des Fahrers angepasst werden. Besonders im Radrennsport ist neben dem hohen Leichtbaupotential eine aerodynamische Sitzhaltung von enormer Bedeutung. Unter Berücksichtigung dieser Anforderungen sind individuelle Bauteile und Strukturen zu entwickeln, da nicht in allen Fällen die Abmessungen der Standardbauteile eine optimale Anpassung zulassen. Im Hinblick auf einen groß gewachsenen Fahrer ist ein verlängerter Vorbau – Gabel-Lenker-Verbindung – für eine aerodynamische Sitzhaltung und somit einen geringen Luftwiderstand unumgänglich. Für die Herstellung solcher maßgeschneiderten Strukturen ist die additive Fertigung aufgrund der hohen gestalterischen Freiheiten und des hohen Individualisierungsgrades besonders geeignet. Im Rahmen dieses Beitrags wird ein Fahrradvorbau für einen überdurchschnittlich langen Fahrer festigkeits- und leichtbauoptimiert konstruiert und nach der Norm DIN EN ISO4210 unter Berücksichtigung der verfahrensspezifischen Randbedingungen beziehungsweise Gestaltungsrichtlinien des Laserstrahlschmelzens ausgelegt. Ausgangsbasis für die Geometriegestaltung sind die Grundlagen der Festigkeitsberechnung. Ein CAD-Modell wird erstellt und aufgrund der komplexen Belastungssituation mit Hilfe der Finite-Elemente-Methode numerisch untersucht sowie optimiert. Nach mehreren Iterationsschritten wird für den Werkstoff TiAl6V4 ein gewichtsreduzierter überlanger Fahrradvorbau von 140mm entwickelt und generativ hergestellt. Der anschließende Vergleich zu einem handelsüblichen Vorbau zeigt eine Gewichtsreduktion von ca. 30%.}}, author = {{Brüggemann, J.P. and Reschetnik, W. and Richard, H.A. and Kullmer, G. and Schramm, B.}}, booktitle = {{Rapid Tech - International Trade Show & Conference for Additive Manufacturing}}, isbn = {{978-3-446-45060-8}}, pages = {{290--300}}, title = {{{Festigkeits- und leichtbauoptimierte Konstruktion und Auslegung eines additiv gefertigten Fahrradvorbaus}}}, doi = {{10.3139/9783446450608.025}}, year = {{2016}}, } @inproceedings{22109, author = {{Reschetnik, W. and Grylls, R. and Bauer, B. and Richard, H.A. and Kullmer, G.}}, title = {{{Fatigue Life Manipulation of SLM Parts}}}, year = {{2016}}, } @inproceedings{22128, author = {{Brüggemann, J.P. and Riemer, A. and Reschetnik, W. and Aydinöz, M.E. and Kullmer, G. and Richard, H.A. and Schaper, M.}}, booktitle = {{DVM - Tagung - Additiv gefertigte Bauteile und Strukturen, Deutscher Verband für Materialforschung und -prüfung e.V.}}, pages = {{101--112}}, title = {{{Optimierung von Fahrradtretkurbeln mittels additiver Fertigung}}}, year = {{2016}}, } @inproceedings{22130, author = {{Reschetnik, W. and Brüggemann, J.P. and Aydinöz, M.E. and Kullmer, G. and Richard, H.A. and Schaper, M.}}, booktitle = {{DVM - Tagung - Additiv gefertigte Bauteile und Strukturen, Deutscher Verband für Materialforschung und -prüfung e.V.}}, pages = {{131--140}}, title = {{{Lebensdauerbeeinflussung durch Additive Fertigung}}}, year = {{2016}}, }