--- _id: '22187' abstract: - lang: eng text: Due to long process times at high temperatures, unmolten polyamide 12 material ages during the manufacturing process. Hence, it needs to be refreshed with new material for further build cycles. In application, refresh rates of about 50 % are commonly used. In this work, the recycling optimized material PA 2221 from EOS is analyzed along a series of 13 build and refresh cycles using a reduced refresh rate of 32 %. Before and after every build, the powder is analyzed regarding melt properties determined by MVR and DSC measurements. Thereby, in-process ageing effects are investigated and the steady-state conditions are determined accordingly. In addition, powder properties are directly linked to resulting mechanical and geometrical part properties. Key findings are a robust DSC measurement method for polyamide 12 powder, constant “circulated” material properties after three build/refresh cycles and robust tensile properties along the whole tested powder life cycle. As a result, process conditions of PA 2221 using reduced refresh rates can be derived from this work. author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: Johannes full_name: Lohn, Johannes last_name: Lohn - first_name: E. full_name: Hermann, E. last_name: Hermann - first_name: Monika full_name: Gessler, Monika last_name: Gessler - first_name: S. full_name: Tenbrink, S. last_name: Tenbrink - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Lohn J, Hermann E, Gessler M, Tenbrink S, Schmid H-J. Material Properties of Laser Sintered Polyamide 12 as Function of Build Cycles Using Low Refresh Rates. In: 26th Annual International Solid Freeform Fabrication Symposium. Vol 26. ; 2015:540-549. doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-43-Josupeit.pdf' apa: Josupeit, S., Lohn, J., Hermann, E., Gessler, M., Tenbrink, S., & Schmid, H.-J. (2015). Material Properties of Laser Sintered Polyamide 12 as Function of Build Cycles Using Low Refresh Rates. In 26th Annual International Solid Freeform Fabrication Symposium (Vol. 26, pp. 540–549). http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-43-Josupeit.pdf bibtex: '@inproceedings{Josupeit_Lohn_Hermann_Gessler_Tenbrink_Schmid_2015, title={Material Properties of Laser Sintered Polyamide 12 as Function of Build Cycles Using Low Refresh Rates}, volume={26}, DOI={http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-43-Josupeit.pdf}, booktitle={26th Annual International Solid Freeform Fabrication Symposium}, author={Josupeit, Stefan and Lohn, Johannes and Hermann, E. and Gessler, Monika and Tenbrink, S. and Schmid, Hans-Joachim}, year={2015}, pages={540–549} }' chicago: Josupeit, Stefan, Johannes Lohn, E. Hermann, Monika Gessler, S. Tenbrink, and Hans-Joachim Schmid. “Material Properties of Laser Sintered Polyamide 12 as Function of Build Cycles Using Low Refresh Rates.” In 26th Annual International Solid Freeform Fabrication Symposium, 26:540–49, 2015. http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-43-Josupeit.pdf. ieee: S. Josupeit, J. Lohn, E. Hermann, M. Gessler, S. Tenbrink, and H.-J. Schmid, “Material Properties of Laser Sintered Polyamide 12 as Function of Build Cycles Using Low Refresh Rates,” in 26th Annual International Solid Freeform Fabrication Symposium, 2015, vol. 26, pp. 540–549. mla: Josupeit, Stefan, et al. “Material Properties of Laser Sintered Polyamide 12 as Function of Build Cycles Using Low Refresh Rates.” 26th Annual International Solid Freeform Fabrication Symposium, vol. 26, 2015, pp. 540–49, doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-43-Josupeit.pdf. short: 'S. Josupeit, J. Lohn, E. Hermann, M. Gessler, S. Tenbrink, H.-J. Schmid, in: 26th Annual International Solid Freeform Fabrication Symposium, 2015, pp. 540–549.' date_created: 2021-05-14T07:46:18Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-43-Josupeit.pdf intvolume: ' 26' language: - iso: eng page: 540-549 publication: 26th Annual International Solid Freeform Fabrication Symposium status: public title: Material Properties of Laser Sintered Polyamide 12 as Function of Build Cycles Using Low Refresh Rates type: conference user_id: '71545' volume: 26 year: '2015' ...