TY - GEN AB - Abstract In this work, the influence of the filler matrix adhesion on the tensile properties of laser-sintered parts built with Polyamide 613 filled with glass beads was investigated. For this purpose, dry blends of glass beads with and without organosilane coupling agents and polyamide powder were prepared and processed into tensile specimens on an EOS P396. The samples were tested both in the dry state and after an accelerated conditioning in a climate chamber. Furthermore, FEM simulations were performed to model the limiting cases of optimum adhesion and no adhesion. By correlating the tensile tests with the simulation results and by analyzing the fracture surfaces, it was shown that the filler matrix adhesion is sufficient in the dry state but is strongly degraded by conditioning. Even the presence of various organosilane thin films could not prevent a strong deterioration of the filler-matrix adhesion and the associated deterioration of the mechanical properties. Since a comparison with an injection molded sample of the same polymer filler combination shows identical behavior after conditioning, it is assumed that this problem is not limited to additively manufactured parts. AU - Kletetzka, Ivo AU - Kosanke, Maren AU - Meinderink, Dennis AU - Neßlinger, Vanessa AU - Grundmeier, Guido AU - Schmid, Hans-Joachim ID - 43049 TI - Influence of the filler matrix adhesion and the effects of conditioning on tensile properties of laser sintered parts built with polyamide glass bead dry blends ER - TY - GEN AU - Kletetzka, Ivo ID - 45783 TI - Tensile Testing for Polymer AM - Best Pratice at the DMRC ER - TY - JOUR AB - In the laser sintering technology, the semi-crystalline polymer material is exposed to elevated temperatures during processing, which leads to serious material ageing for most materials. This has already been investigated intensively by various authors. However, the ageing of the material at ambient temperatures during shelf life has not been the focus so far. The need to analyse the shelf life can be derived from an ecological and economic point of view. This work is focusing on the shelf life of PA2200 (PA12). To reduce the potential influences of powder production fluctuations, two different powder batches stored for 5.5 years and 6.5 years are investigated and compared to a reference powder produced 0.5 years before these investigations. Multiple powder analyses and part characterisations have been performed. A significant yellowing and molecular chain length reduction can be derived from the measurement results. Whereas the influence on mechanical part performance was minor, the parts built with the stored powders are more yellowish. As it is most likely that this is due to the consumption of polyamide stabilisers, it can be assumed that these parts will be subject to significantly faster ageing. Therefore, it is still not recommended to use the stored powders for critical parts or light intense and humid environments. AU - Klippstein, Sven Helge AU - Kletetzka, Ivo AU - Sural, Ilknur AU - Schmid, Hans-Joachim ID - 43046 JF - The International Journal of Advanced Manufacturing Technology KW - Selective laser sintering KW - Shelf life KW - Polyamide 12 KW - powder KW - PA2200 KW - material ageing TI - Influence of a prolonged shelf time on PA12 laser sintering powder and resulting part properties ER - TY - GEN AU - Sajadi, Said ID - 46861 TI - Charakterisierung und Bewertung von flammgeschützten PA12 Pulvermischungen hinsichtlich der Verarbeitbarkeit im Lasersinter-Prozess ER - TY - CONF AU - Troschitz, Juliane AU - Vorderbrüggen, Julian Heinrich Josef AU - Gude, Maik AU - Meschut, Gerson ID - 46866 T2 - Proceedings of the 23rd International Conference on Composite Materials (ICCM23) TI - Clinching and resistance spot welding of thermoplastic composites with metals using inserts as joining interfaces ER - TY - CHAP AU - Dieter, Peter ID - 46867 SN - 0302-9743 T2 - Lecture Notes in Computer Science TI - A Regret Policy for the Dynamic Vehicle Routing Problem with Time Windows ER - TY - CHAP AU - Menge, Dennis AU - Milaege, Dennis AU - Hoyer, Kay-Peter AU - Schmid, Hans-Joachim AU - Schaper, Mirko ED - Horwath, Illona ED - Schweizer, Swetlana ID - 46870 SN - 2703-1543 T2 - Climate Protection, Resource Efficiency, and Sustainable Engineering TI - Case Study IV: Individualized Medical Technology using Additive Manufacturing ER - TY - CONF AU - Hansmeier, Philipp ID - 46892 T2 - Proceedings of the 18th International Conference on Wirtschaftsinformatik TI - Exploring Platform Types and Related Concepts in Service Research – A Systematic Scoping Literature Review ER - TY - BOOK ED - Alpermann, Ilsabe ED - Besser, Beate ED - Evang, Martin ED - Schroeter-Wittke, Harald ID - 46854 TI - Ich lobe meinen Gott, der aus der Tiefe mich holt. Hymnologische Kommentare zu den Liedern im Ergänzungsheft zum Evangelischen Gesangbuch. Jan Janssen zum 60. Geburtstag. HEG 3/Ergänzungsheft, Göttingen 2023 ER - TY - CHAP AU - Schroeter-Wittke, Harald AU - Kirsner, Inge ID - 46896 T2 - Predigtstudien VI/1 TI - XXmas: Macht gebären statt Macht gebaren. 1. Weihnachtstag (Christfest I) 2Mose 2,1-10 ER -