--- _id: '22178' author: - first_name: Patrick full_name: Delfs, Patrick last_name: Delfs - first_name: Z. full_name: Li, Z. last_name: Li - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Delfs P, Li Z, Schmid H-J. Mass finishing of laser sintered parts. In: 26th Annual International Solid Freeform Fabrication Symposium. Vol 26. ; 2015:514-526. doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-41-Delfs.pdf' apa: Delfs, P., Li, Z., & Schmid, H.-J. (2015). Mass finishing of laser sintered parts. In 26th Annual International Solid Freeform Fabrication Symposium (Vol. 26, pp. 514–526). http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-41-Delfs.pdf bibtex: '@inproceedings{Delfs_Li_Schmid_2015, title={Mass finishing of laser sintered parts}, volume={26}, DOI={http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-41-Delfs.pdf}, booktitle={26th Annual International Solid Freeform Fabrication Symposium}, author={Delfs, Patrick and Li, Z. and Schmid, Hans-Joachim}, year={2015}, pages={514–526} }' chicago: Delfs, Patrick, Z. Li, and Hans-Joachim Schmid. “Mass Finishing of Laser Sintered Parts.” In 26th Annual International Solid Freeform Fabrication Symposium, 26:514–26, 2015. http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-41-Delfs.pdf. ieee: P. Delfs, Z. Li, and H.-J. Schmid, “Mass finishing of laser sintered parts,” in 26th Annual International Solid Freeform Fabrication Symposium, 2015, vol. 26, pp. 514–526. mla: Delfs, Patrick, et al. “Mass Finishing of Laser Sintered Parts.” 26th Annual International Solid Freeform Fabrication Symposium, vol. 26, 2015, pp. 514–26, doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-41-Delfs.pdf. short: 'P. Delfs, Z. Li, H.-J. Schmid, in: 26th Annual International Solid Freeform Fabrication Symposium, 2015, pp. 514–526.' date_created: 2021-05-14T07:46:07Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-41-Delfs.pdf intvolume: ' 26' language: - iso: eng page: 514-526 publication: 26th Annual International Solid Freeform Fabrication Symposium status: public title: Mass finishing of laser sintered parts type: conference user_id: '71545' volume: 26 year: '2015' ... --- _id: '22179' abstract: - lang: eng text: The temperature distribution and history within laser sintered part cakes is an important aspect regarding the process quality and reproducibility of the polymer laser sintering process. Especially the temperature history during the build and cooling phase is decisive for powder ageing effects and the development of part quality characteristics. In this work, a measurement system for three-dimensional in-process temperature measurements is set up and the influence of different parameters on the inner part cake temperature distribution and history is analyzed. Important factors are not only geometrical build job parameters like the part packing density and build height, but also process parameters like the layer thickness and bulk powder density. Individual in-process temperature profiles at different positions within a part cake are finally correlated with powder ageing effects. The results of this work help to understand the temperature history dependency of powder and part properties and can therefore be used to develop optimized process controls. author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Schmid H-J. Temperature History within Laser Sintered Part Cakes and its Influence on Process Quality. In: 26th Annual International Solid Freeform Fabrication Symposium. Vol 26. ; 2015:190-199. doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-15-Josupeit.pdf' apa: Josupeit, S., & Schmid, H.-J. (2015). Temperature History within Laser Sintered Part Cakes and its Influence on Process Quality. In 26th Annual International Solid Freeform Fabrication Symposium (Vol. 26, pp. 190–199). http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-15-Josupeit.pdf bibtex: '@inproceedings{Josupeit_Schmid_2015, title={Temperature History within Laser Sintered Part Cakes and its Influence on Process Quality}, volume={26}, DOI={http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-15-Josupeit.pdf}, booktitle={26th Annual International Solid Freeform Fabrication Symposium}, author={Josupeit, Stefan and Schmid, Hans-Joachim}, year={2015}, pages={190–199} }' chicago: Josupeit, Stefan, and Hans-Joachim Schmid. “Temperature History within Laser Sintered Part Cakes and Its Influence on Process Quality.” In 26th Annual International Solid Freeform Fabrication Symposium, 26:190–99, 2015. http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-15-Josupeit.pdf. ieee: S. Josupeit and H.-J. Schmid, “Temperature History within Laser Sintered Part Cakes and its Influence on Process Quality,” in 26th Annual International Solid Freeform Fabrication Symposium, 2015, vol. 26, pp. 190–199. mla: Josupeit, Stefan, and Hans-Joachim Schmid. “Temperature History within Laser Sintered Part Cakes and Its Influence on Process Quality.” 26th Annual International Solid Freeform Fabrication Symposium, vol. 26, 2015, pp. 190–99, doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-15-Josupeit.pdf. short: 'S. Josupeit, H.-J. Schmid, in: 26th Annual International Solid Freeform Fabrication Symposium, 2015, pp. 190–199.' date_created: 2021-05-14T07:46:09Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-15-Josupeit.pdf intvolume: ' 26' language: - iso: eng page: 190-199 publication: 26th Annual International Solid Freeform Fabrication Symposium status: public title: Temperature History within Laser Sintered Part Cakes and its Influence on Process Quality type: conference user_id: '71545' volume: 26 year: '2015' ... --- _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' ... --- _id: '22189' abstract: - lang: eng text: The layered structure of Additive Manufacturing processes results in a stairstepping effect of the surface topographies. In general the impact of this effect strongly depends on the build angle of a surface, whereas the overall surface roughness is caused by the resolution of the specific AM process. The aim of this work is the prediction of the surface quality in dependence of the building orientation of a part. These results can finally be used to optimize the orientation to get a desired surface quality. As not every area of a part can be optimized, a predetermination of areas can be used to improve the surface quality of important areas. The model uses the digital STL format of a part as this is necessary for all AM machines to build it. Each triangle is assigned with a roughness value and by testing different orientations the best one can be found. This approach needs a database for the surface qualities. This must be done separately for each Additive Manufacturing process and is shown exemplary with a surface topography simulation for the laser sintering process. author: - first_name: Patrick full_name: Delfs, Patrick last_name: Delfs - first_name: Marcel full_name: Toews, Marcel last_name: Toews - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Delfs P, Toews M, Schmid H-J. Surface roughness optimized alignment of parts for additive manufacturing processes. In: 26th Annual International Solid Freeform Fabrication Symposium. Vol 26. ; 2015:1334-1344. doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-107-Delfs.pdf' apa: Delfs, P., Toews, M., & Schmid, H.-J. (2015). Surface roughness optimized alignment of parts for additive manufacturing processes. In 26th Annual International Solid Freeform Fabrication Symposium (Vol. 26, pp. 1334–1344). http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-107-Delfs.pdf bibtex: '@inproceedings{Delfs_Toews_Schmid_2015, title={Surface roughness optimized alignment of parts for additive manufacturing processes}, volume={26}, DOI={http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-107-Delfs.pdf}, booktitle={26th Annual International Solid Freeform Fabrication Symposium}, author={Delfs, Patrick and Toews, Marcel and Schmid, Hans-Joachim}, year={2015}, pages={1334–1344} }' chicago: Delfs, Patrick, Marcel Toews, and Hans-Joachim Schmid. “Surface Roughness Optimized Alignment of Parts for Additive Manufacturing Processes.” In 26th Annual International Solid Freeform Fabrication Symposium, 26:1334–44, 2015. http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-107-Delfs.pdf. ieee: P. Delfs, M. Toews, and H.-J. Schmid, “Surface roughness optimized alignment of parts for additive manufacturing processes,” in 26th Annual International Solid Freeform Fabrication Symposium, 2015, vol. 26, pp. 1334–1344. mla: Delfs, Patrick, et al. “Surface Roughness Optimized Alignment of Parts for Additive Manufacturing Processes.” 26th Annual International Solid Freeform Fabrication Symposium, vol. 26, 2015, pp. 1334–44, doi:http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-107-Delfs.pdf. short: 'P. Delfs, M. Toews, H.-J. Schmid, in: 26th Annual International Solid Freeform Fabrication Symposium, 2015, pp. 1334–1344.' date_created: 2021-05-14T07:46:20Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/sites/default/files/2015/2015-107-Delfs.pdf intvolume: ' 26' language: - iso: eng page: 1334-1344 publication: 26th Annual International Solid Freeform Fabrication Symposium status: public title: Surface roughness optimized alignment of parts for additive manufacturing processes type: conference user_id: '71545' volume: 26 year: '2015' ... --- _id: '22199' abstract: - lang: eng text: Powder ageing effects due to thermal load usually lead to a limited recyclability of unmolten polyamide 12 powders in the laser sintering process. In this work, the recycling optimized material PA 2221 is analyzed regarding its ageing behavior along a series of more than ten build/refresh cycles using a refresh ratio of about 30%. Thereby, the melt viscosity is measured before and after every cycle and the “steady-state” condition is determined accordingly. In addition, the material properties of parts manufactured with PA 2221 are discussed dependent on different process parameters and compared to parts made of standard PA 2200 material with a refresh rate of about 50%. These parameters include the mechanical properties as well as for example the impact strength and geometrical properties as function of layer thickness and testing temperature. As a result, the optimal process conditions and achievable material properties for PA 2221 can be derived from this work. author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: S. full_name: Tutzschky, S. last_name: Tutzschky - first_name: M. full_name: Gessler, M. last_name: Gessler - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Tutzschky S, Gessler M, Schmid H-J. Powder ageing and material properties of laser sintered polyamide 12 using low refresh rates. In: Proceedings of the Rapid Tech 2015. Springer Vieweg; 2015:63-78. doi:10.1007/978-3-662-48473-9_5' apa: Josupeit, S., Tutzschky, S., Gessler, M., & Schmid, H.-J. (2015). Powder ageing and material properties of laser sintered polyamide 12 using low refresh rates. In Proceedings of the Rapid Tech 2015 (pp. 63–78). Springer Vieweg. https://doi.org/10.1007/978-3-662-48473-9_5 bibtex: '@inproceedings{Josupeit_Tutzschky_Gessler_Schmid_2015, title={Powder ageing and material properties of laser sintered polyamide 12 using low refresh rates}, DOI={10.1007/978-3-662-48473-9_5}, booktitle={Proceedings of the Rapid Tech 2015}, publisher={Springer Vieweg}, author={Josupeit, Stefan and Tutzschky, S. and Gessler, M. and Schmid, Hans-Joachim}, year={2015}, pages={63–78} }' chicago: Josupeit, Stefan, S. Tutzschky, M. Gessler, and Hans-Joachim Schmid. “Powder Ageing and Material Properties of Laser Sintered Polyamide 12 Using Low Refresh Rates.” In Proceedings of the Rapid Tech 2015, 63–78. Springer Vieweg, 2015. https://doi.org/10.1007/978-3-662-48473-9_5. ieee: S. Josupeit, S. Tutzschky, M. Gessler, and H.-J. Schmid, “Powder ageing and material properties of laser sintered polyamide 12 using low refresh rates,” in Proceedings of the Rapid Tech 2015, 2015, pp. 63–78. mla: Josupeit, Stefan, et al. “Powder Ageing and Material Properties of Laser Sintered Polyamide 12 Using Low Refresh Rates.” Proceedings of the Rapid Tech 2015, Springer Vieweg, 2015, pp. 63–78, doi:10.1007/978-3-662-48473-9_5. short: 'S. Josupeit, S. Tutzschky, M. Gessler, H.-J. Schmid, in: Proceedings of the Rapid Tech 2015, Springer Vieweg, 2015, pp. 63–78.' date_created: 2021-05-14T07:46:32Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: 10.1007/978-3-662-48473-9_5 language: - iso: eng page: 63-78 publication: Proceedings of the Rapid Tech 2015 publication_identifier: isbn: - 978-3-662-48473-9 publisher: Springer Vieweg status: public title: Powder ageing and material properties of laser sintered polyamide 12 using low refresh rates type: conference user_id: '71545' year: '2015' ... --- _id: '23074' author: - first_name: Isabel full_name: Koke, Isabel last_name: Koke - first_name: Katharina full_name: Dibblee, Katharina last_name: Dibblee - first_name: Frederik full_name: Hankeln, Frederik last_name: Hankeln - first_name: Stefan full_name: Seidel, Stefan last_name: Seidel - first_name: Ansgar full_name: Trächtler, Ansgar id: '552' last_name: Trächtler - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Koke I, Dibblee K, Hankeln F, Seidel S, Trächtler A, Schmid H-J. Tutorenprogramm und Vertiefungsberatung stellen Weichen in entscheidenden Phasen des Student Life-Cycles in Maschinenbaustudiengängen. In: 44. Jahrestagung Der Deutschen Gesellschaft Für Hochschuldidaktik - Hochschuldidaktik Im Dialog, Paderborn. ; 2015.' apa: Koke, I., Dibblee, K., Hankeln, F., Seidel, S., Trächtler, A., & Schmid, H.-J. (2015). Tutorenprogramm und Vertiefungsberatung stellen Weichen in entscheidenden Phasen des Student Life-Cycles in Maschinenbaustudiengängen. In 44. Jahrestagung der Deutschen Gesellschaft für Hochschuldidaktik - Hochschuldidaktik im Dialog, Paderborn. bibtex: '@inproceedings{Koke_Dibblee_Hankeln_Seidel_Trächtler_Schmid_2015, title={Tutorenprogramm und Vertiefungsberatung stellen Weichen in entscheidenden Phasen des Student Life-Cycles in Maschinenbaustudiengängen}, booktitle={ 44. Jahrestagung der Deutschen Gesellschaft für Hochschuldidaktik - Hochschuldidaktik im Dialog, Paderborn}, author={Koke, Isabel and Dibblee, Katharina and Hankeln, Frederik and Seidel, Stefan and Trächtler, Ansgar and Schmid, Hans-Joachim}, year={2015} }' chicago: Koke, Isabel, Katharina Dibblee, Frederik Hankeln, Stefan Seidel, Ansgar Trächtler, and Hans-Joachim Schmid. “Tutorenprogramm Und Vertiefungsberatung Stellen Weichen in Entscheidenden Phasen Des Student Life-Cycles in Maschinenbaustudiengängen.” In 44. Jahrestagung Der Deutschen Gesellschaft Für Hochschuldidaktik - Hochschuldidaktik Im Dialog, Paderborn, 2015. ieee: I. Koke, K. Dibblee, F. Hankeln, S. Seidel, A. Trächtler, and H.-J. Schmid, “Tutorenprogramm und Vertiefungsberatung stellen Weichen in entscheidenden Phasen des Student Life-Cycles in Maschinenbaustudiengängen,” in 44. Jahrestagung der Deutschen Gesellschaft für Hochschuldidaktik - Hochschuldidaktik im Dialog, Paderborn, 2015. mla: Koke, Isabel, et al. “Tutorenprogramm Und Vertiefungsberatung Stellen Weichen in Entscheidenden Phasen Des Student Life-Cycles in Maschinenbaustudiengängen.” 44. Jahrestagung Der Deutschen Gesellschaft Für Hochschuldidaktik - Hochschuldidaktik Im Dialog, Paderborn, 2015. short: 'I. Koke, K. Dibblee, F. Hankeln, S. Seidel, A. Trächtler, H.-J. Schmid, in: 44. Jahrestagung Der Deutschen Gesellschaft Für Hochschuldidaktik - Hochschuldidaktik Im Dialog, Paderborn, 2015.' date_created: 2021-08-09T06:42:41Z date_updated: 2022-01-06T06:55:45Z department: - _id: '153' language: - iso: eng publication: ' 44. Jahrestagung der Deutschen Gesellschaft für Hochschuldidaktik - Hochschuldidaktik im Dialog, Paderborn' status: public title: Tutorenprogramm und Vertiefungsberatung stellen Weichen in entscheidenden Phasen des Student Life-Cycles in Maschinenbaustudiengängen type: conference user_id: '24876' year: '2015' ... --- _id: '26125' abstract: - lang: eng text: We investigated an explanation for the length dependence of apparent wall slip in capillary and slit die experiments that had been implied in earlier studies. Firstly, we used a very long slit die fitted with six equidistant pressure transducers and an adjustable outlet. It was found that, all other parameters being equal, the impact of pressure on the flow behavior of suspensions was not different from the impact on the unfilled matrix fluid. Particle-related properties, such as apparent wall slip, were therefore not influenced by pressure as assumed by other authors. Secondly, we determined wall slip velocities by both the Mooney method and numerical simulation, based on an implementation of Phillips constitutive equation for particle migration. This led to a similar length dependence of wall slip as had been reported in an earlier work. We concluded that this was due to the transient nature of particle migration and its interrelationship with apparent wall slip, rather than an influence of pressure. author: - first_name: Sven full_name: Pieper, Sven last_name: Pieper - first_name: Nadine full_name: Kirchhoff, Nadine last_name: Kirchhoff - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: Pieper S, Kirchhoff N, Schmid H-J. Absence of pressure sensitivity of apparent wall slip in pressure-driven flow of non-colloidal suspensions. Rheologica Acta. Published online 2014:69-75. doi:10.1007/s00397-014-0815-x apa: Pieper, S., Kirchhoff, N., & Schmid, H.-J. (2014). Absence of pressure sensitivity of apparent wall slip in pressure-driven flow of non-colloidal suspensions. Rheologica Acta, 69–75. https://doi.org/10.1007/s00397-014-0815-x bibtex: '@article{Pieper_Kirchhoff_Schmid_2014, title={Absence of pressure sensitivity of apparent wall slip in pressure-driven flow of non-colloidal suspensions}, DOI={10.1007/s00397-014-0815-x}, journal={Rheologica Acta}, author={Pieper, Sven and Kirchhoff, Nadine and Schmid, Hans-Joachim}, year={2014}, pages={69–75} }' chicago: Pieper, Sven, Nadine Kirchhoff, and Hans-Joachim Schmid. “Absence of Pressure Sensitivity of Apparent Wall Slip in Pressure-Driven Flow of Non-Colloidal Suspensions.” Rheologica Acta, 2014, 69–75. https://doi.org/10.1007/s00397-014-0815-x. ieee: 'S. Pieper, N. Kirchhoff, and H.-J. Schmid, “Absence of pressure sensitivity of apparent wall slip in pressure-driven flow of non-colloidal suspensions,” Rheologica Acta, pp. 69–75, 2014, doi: 10.1007/s00397-014-0815-x.' mla: Pieper, Sven, et al. “Absence of Pressure Sensitivity of Apparent Wall Slip in Pressure-Driven Flow of Non-Colloidal Suspensions.” Rheologica Acta, 2014, pp. 69–75, doi:10.1007/s00397-014-0815-x. short: S. Pieper, N. Kirchhoff, H.-J. Schmid, Rheologica Acta (2014) 69–75. date_created: 2021-10-13T14:05:58Z date_updated: 2022-01-06T06:57:16Z doi: 10.1007/s00397-014-0815-x language: - iso: eng page: 69-75 publication: Rheologica Acta publication_identifier: issn: - 0035-4511 - 1435-1528 publication_status: published status: public title: Absence of pressure sensitivity of apparent wall slip in pressure-driven flow of non-colloidal suspensions type: journal_article user_id: '70093' year: '2014' ... --- _id: '26126' abstract: - lang: eng text: Ultrafine dust separation from different sources like industry, traffic, or private households has become increasingly important in the last decade. A compact baghouse filter system has been developed which is suitable for pellet heaters. For filtration, a precoat material is required to prevent clogging of the filter media by the ultrafine dust particles. In order to ensure the best performance of this filter system, different combinations of filter media and precoat materials, e.g., grade efficiencies and the cake area load for the various filter media, were investigated in a special test rig. With this highly efficient technology, extremely high separation efficiencies of > 99 % and ultrafine dust concentrations of > 1 mg cm−3 could be reached in a long-term stable process. author: - first_name: Sascha full_name: Schiller, Sascha last_name: Schiller - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: Schiller S, Schmid H-J. Ultrafine Dust Filtration Using Precoat Materials Considering the Influence of Filter Media. Chemical Engineering & Technology. Published online 2014:1009-1020. doi:10.1002/ceat.201300856 apa: Schiller, S., & Schmid, H.-J. (2014). Ultrafine Dust Filtration Using Precoat Materials Considering the Influence of Filter Media. Chemical Engineering & Technology, 1009–1020. https://doi.org/10.1002/ceat.201300856 bibtex: '@article{Schiller_Schmid_2014, title={Ultrafine Dust Filtration Using Precoat Materials Considering the Influence of Filter Media}, DOI={10.1002/ceat.201300856}, journal={Chemical Engineering & Technology}, author={Schiller, Sascha and Schmid, Hans-Joachim}, year={2014}, pages={1009–1020} }' chicago: Schiller, Sascha, and Hans-Joachim Schmid. “Ultrafine Dust Filtration Using Precoat Materials Considering the Influence of Filter Media.” Chemical Engineering & Technology, 2014, 1009–20. https://doi.org/10.1002/ceat.201300856. ieee: 'S. Schiller and H.-J. Schmid, “Ultrafine Dust Filtration Using Precoat Materials Considering the Influence of Filter Media,” Chemical Engineering & Technology, pp. 1009–1020, 2014, doi: 10.1002/ceat.201300856.' mla: Schiller, Sascha, and Hans-Joachim Schmid. “Ultrafine Dust Filtration Using Precoat Materials Considering the Influence of Filter Media.” Chemical Engineering & Technology, 2014, pp. 1009–20, doi:10.1002/ceat.201300856. short: S. Schiller, H.-J. Schmid, Chemical Engineering & Technology (2014) 1009–1020. date_created: 2021-10-13T14:07:13Z date_updated: 2022-01-06T06:57:16Z doi: 10.1002/ceat.201300856 language: - iso: eng page: 1009-1020 publication: Chemical Engineering & Technology publication_identifier: issn: - 0930-7516 publication_status: published status: public title: Ultrafine Dust Filtration Using Precoat Materials Considering the Influence of Filter Media type: journal_article user_id: '70093' year: '2014' ... --- _id: '26127' abstract: - lang: eng text: Capillary forces are very important as they exceed in general other adhesion forces. But at the same time the exact calculation of these forces is very complex, so often assumptions and approximations are used. Previous research was done with regard to micrometer sized particles, but the behavior of nanoscale particles is different. Hence, the results for micrometer sized particles cannot be directly transferred when considering nanoscale particles. Therefore, a simulation method was developed to calculate numerically the shape of a rotationally symmetrical capillary bridge between two spherical particles or a particle and a plate. The capillary bridge in the gap between the particles is formed due to capillary condensation and is in thermodynamic equilibrium with the gas phase. Hence the Kelvin equation and the Young–Laplace equation can be used to calculate the profile of the capillary bridge, depending on the relative humidity of the surrounding air. The bridge profile consists of several elements that are determined consecutively and interpolated linearly. After the shape is determined, the volume and force, divided into capillary pressure force and surface tension force, can be calculated. The validation of this numerical model will be shown by comparison with several different analytical calculations for micrometer-sized particles. Furthermore, it is demonstrated that two often used approximations, (1) the toroidal approximation and (2) the use of an effective radius, cannot be used for nanoscale particles without remarkable mistake. It will be discussed how the capillary force and its components depend on different parameters, like particle size, relative humidity, contact angle, and distance, respectively. The rupture of a capillary bridge due to particle separation will also be presented. author: - first_name: Michael full_name: Dörmann, Michael last_name: Dörmann - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: Dörmann M, Schmid H-J. Simulation of Capillary Bridges between Nanoscale Particles. Langmuir. Published online 2014:1055-1062. doi:10.1021/la404409k apa: Dörmann, M., & Schmid, H.-J. (2014). Simulation of Capillary Bridges between Nanoscale Particles. Langmuir, 1055–1062. https://doi.org/10.1021/la404409k bibtex: '@article{Dörmann_Schmid_2014, title={Simulation of Capillary Bridges between Nanoscale Particles}, DOI={10.1021/la404409k}, journal={Langmuir}, author={Dörmann, Michael and Schmid, Hans-Joachim}, year={2014}, pages={1055–1062} }' chicago: Dörmann, Michael, and Hans-Joachim Schmid. “Simulation of Capillary Bridges between Nanoscale Particles.” Langmuir, 2014, 1055–62. https://doi.org/10.1021/la404409k. ieee: 'M. Dörmann and H.-J. Schmid, “Simulation of Capillary Bridges between Nanoscale Particles,” Langmuir, pp. 1055–1062, 2014, doi: 10.1021/la404409k.' mla: Dörmann, Michael, and Hans-Joachim Schmid. “Simulation of Capillary Bridges between Nanoscale Particles.” Langmuir, 2014, pp. 1055–62, doi:10.1021/la404409k. short: M. Dörmann, H.-J. Schmid, Langmuir (2014) 1055–1062. date_created: 2021-10-13T14:09:40Z date_updated: 2022-01-06T06:57:16Z doi: 10.1021/la404409k language: - iso: eng page: 1055-1062 publication: Langmuir publication_identifier: issn: - 0743-7463 - 1520-5827 publication_status: published status: public title: Simulation of Capillary Bridges between Nanoscale Particles type: journal_article user_id: '70093' year: '2014' ... --- _id: '22176' abstract: - lang: eng text: One barrier of laser sintering (LS) to become the main process for Direct Manufacturing (DM) is the surface quality of LS parts. Hence, the property which has to be improved is the rough surfaces of LS parts due to the layered structure. Another additional effect is the incomplete melting of powder particles on the surface due to the high process temperature. In this paper we demonstrate our approach of a theoretical model for the topography of LS part surfaces. We investigated the surface roughness as a function of surface orientation. Considering that the model involves further variables as layer thickness, particle density and particle size distribution to describe the topography precisely. Experimental results were used to optimize and check the results of the model. author: - first_name: Patrick full_name: Delfs, Patrick last_name: Delfs - first_name: A.A. full_name: Herale, A.A. last_name: Herale - first_name: Z. full_name: Li, Z. last_name: Li - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Delfs P, Herale AA, Li Z, Schmid H-J. Simulation of the Surface Topography on Laser Sintered Polymer Parts. In: 25th Annual International Solid Freeform Fabrication Symposium. Vol 25. ; 2014:1250-1258. doi:http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf' apa: Delfs, P., Herale, A. A., Li, Z., & Schmid, H.-J. (2014). Simulation of the Surface Topography on Laser Sintered Polymer Parts. In 25th Annual International Solid Freeform Fabrication Symposium (Vol. 25, pp. 1250–1258). http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf bibtex: '@inproceedings{Delfs_Herale_Li_Schmid_2014, title={Simulation of the Surface Topography on Laser Sintered Polymer Parts}, volume={25}, DOI={http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf}, booktitle={25th Annual International Solid Freeform Fabrication Symposium}, author={Delfs, Patrick and Herale, A.A. and Li, Z. and Schmid, Hans-Joachim}, year={2014}, pages={1250–1258} }' chicago: Delfs, Patrick, A.A. Herale, Z. Li, and Hans-Joachim Schmid. “Simulation of the Surface Topography on Laser Sintered Polymer Parts.” In 25th Annual International Solid Freeform Fabrication Symposium, 25:1250–58, 2014. http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf. ieee: P. Delfs, A. A. Herale, Z. Li, and H.-J. Schmid, “Simulation of the Surface Topography on Laser Sintered Polymer Parts,” in 25th Annual International Solid Freeform Fabrication Symposium, 2014, vol. 25, pp. 1250–1258. mla: Delfs, Patrick, et al. “Simulation of the Surface Topography on Laser Sintered Polymer Parts.” 25th Annual International Solid Freeform Fabrication Symposium, vol. 25, 2014, pp. 1250–58, doi:http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf. short: 'P. Delfs, A.A. Herale, Z. Li, H.-J. Schmid, in: 25th Annual International Solid Freeform Fabrication Symposium, 2014, pp. 1250–1258.' date_created: 2021-05-14T07:46:05Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf intvolume: ' 25' language: - iso: eng page: 1250-1258 publication: 25th Annual International Solid Freeform Fabrication Symposium status: public title: Simulation of the Surface Topography on Laser Sintered Polymer Parts type: conference user_id: '71545' volume: 25 year: '2014' ... --- _id: '22177' abstract: - lang: eng text: An uneven temperature distribution and varying cooling rates at different positions within the part cake are two of the most important challenges regarding the part quality and reproducibility of the polymer laser sintering process. In the presented work, a temperature measurement system is implemented within an EOSINT P395 laser sintering system. It allows the determination of a three dimensional temperature distribution and history during the full build and cooling process. The influence of important job parameters, for example the packing density, job height and layer thickness, can be figured out. In combination with a finite element simulation of the cooling process, the temperature measurement will be the basis for optimized process controls. author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Schmid H-J. Three-dimensional in-process temperature measurement of laser sintered part cakes. In: 25th Annual International Solid Freeform Fabrication Symposium. Vol 25. ; 2014:49-58. doi:http://utw10945.utweb.utexas.edu/sites/default/files/2014-006-Josupeit.pdf' apa: Josupeit, S., & Schmid, H.-J. (2014). Three-dimensional in-process temperature measurement of laser sintered part cakes. In 25th Annual International Solid Freeform Fabrication Symposium (Vol. 25, pp. 49–58). http://utw10945.utweb.utexas.edu/sites/default/files/2014-006-Josupeit.pdf bibtex: '@inproceedings{Josupeit_Schmid_2014, title={Three-dimensional in-process temperature measurement of laser sintered part cakes}, volume={25}, DOI={http://utw10945.utweb.utexas.edu/sites/default/files/2014-006-Josupeit.pdf}, booktitle={25th Annual International Solid Freeform Fabrication Symposium}, author={Josupeit, Stefan and Schmid, Hans-Joachim}, year={2014}, pages={49–58} }' chicago: Josupeit, Stefan, and Hans-Joachim Schmid. “Three-Dimensional in-Process Temperature Measurement of Laser Sintered Part Cakes.” In 25th Annual International Solid Freeform Fabrication Symposium, 25:49–58, 2014. http://utw10945.utweb.utexas.edu/sites/default/files/2014-006-Josupeit.pdf. ieee: S. Josupeit and H.-J. Schmid, “Three-dimensional in-process temperature measurement of laser sintered part cakes,” in 25th Annual International Solid Freeform Fabrication Symposium, 2014, vol. 25, pp. 49–58. mla: Josupeit, Stefan, and Hans-Joachim Schmid. “Three-Dimensional in-Process Temperature Measurement of Laser Sintered Part Cakes.” 25th Annual International Solid Freeform Fabrication Symposium, vol. 25, 2014, pp. 49–58, doi:http://utw10945.utweb.utexas.edu/sites/default/files/2014-006-Josupeit.pdf. short: 'S. Josupeit, H.-J. Schmid, in: 25th Annual International Solid Freeform Fabrication Symposium, 2014, pp. 49–58.' date_created: 2021-05-14T07:46:06Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/sites/default/files/2014-006-Josupeit.pdf intvolume: ' 25' language: - iso: eng page: 49-58 publication: 25th Annual International Solid Freeform Fabrication Symposium status: public title: Three-dimensional in-process temperature measurement of laser sintered part cakes type: conference user_id: '71545' volume: 25 year: '2014' ... --- _id: '22184' abstract: - lang: eng text: Polymer laser sintering is one of the most important additive manufacturing technologies for the tool-less production of three-dimensional prototypes and end-use parts. In this process, parts are manufactured layerwise out of a polymer powder by laser exposure. After the building process, these parts are located within a loose bulk powder cake. Due to long process times and high process temperatures, this powder ages thermally, which reduces the recyclability of the material. As a result, mixtures of used and virgin powder ("refreshed" powder) with a mixture ratio of approximately 50% are commonly used in the industry. The goal of this work is to determine the exact influence of different powder ages on resulting part quality characteristics, especially the mechanical behavior and the surface quality. Therefore, refreshed powder with different qualities adjusted by the melt volume rate (MVR) was processed along a defined process quality chain. To analyze the part qualities, mechanical tensile and profilometer tests were performed. The focus is on an application-oriented test set-up to ensure the usability of the results in the industry. The material used is polyamide 12 (PA 2200) processed on an EOSINT P395 laser sintering system from EOS GmbH, Krailling, Germany. author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: Stefan full_name: Rüsenberg, Stefan last_name: Rüsenberg - first_name: N. full_name: Rupp, N. last_name: Rupp - first_name: Monika full_name: Gessler, Monika last_name: Gessler - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Rüsenberg S, Rupp N, Gessler M, Schmid H-J. Thermal ageing of polyamide 12 used for polymer laser sintering - influence on part quality characteristics. In: 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014). Vol 72. ; 2014:2383-2385. doi:https://www.researchgate.net/publication/283135483_Thermal_ageing_of_polyamide_12_used_for_polymer_laser_sintering_-_Influence_on_part_quality_characteristics' apa: Josupeit, S., Rüsenberg, S., Rupp, N., Gessler, M., & Schmid, H.-J. (2014). Thermal ageing of polyamide 12 used for polymer laser sintering - influence on part quality characteristics. In 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014) (Vol. 72, pp. 2383–2385). https://www.researchgate.net/publication/283135483_Thermal_ageing_of_polyamide_12_used_for_polymer_laser_sintering_-_Influence_on_part_quality_characteristics bibtex: '@inproceedings{Josupeit_Rüsenberg_Rupp_Gessler_Schmid_2014, title={Thermal ageing of polyamide 12 used for polymer laser sintering - influence on part quality characteristics}, volume={72}, DOI={https://www.researchgate.net/publication/283135483_Thermal_ageing_of_polyamide_12_used_for_polymer_laser_sintering_-_Influence_on_part_quality_characteristics}, number={3}, booktitle={72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014)}, author={Josupeit, Stefan and Rüsenberg, Stefan and Rupp, N. and Gessler, Monika and Schmid, Hans-Joachim}, year={2014}, pages={2383–2385} }' chicago: Josupeit, Stefan, Stefan Rüsenberg, N. Rupp, Monika Gessler, and Hans-Joachim Schmid. “Thermal Ageing of Polyamide 12 Used for Polymer Laser Sintering - Influence on Part Quality Characteristics.” In 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014), 72:2383–85, 2014. https://www.researchgate.net/publication/283135483_Thermal_ageing_of_polyamide_12_used_for_polymer_laser_sintering_-_Influence_on_part_quality_characteristics. ieee: S. Josupeit, S. Rüsenberg, N. Rupp, M. Gessler, and H.-J. Schmid, “Thermal ageing of polyamide 12 used for polymer laser sintering - influence on part quality characteristics,” in 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014), 2014, vol. 72, no. 3, pp. 2383–2385. mla: Josupeit, Stefan, et al. “Thermal Ageing of Polyamide 12 Used for Polymer Laser Sintering - Influence on Part Quality Characteristics.” 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014), vol. 72, no. 3, 2014, pp. 2383–85, doi:https://www.researchgate.net/publication/283135483_Thermal_ageing_of_polyamide_12_used_for_polymer_laser_sintering_-_Influence_on_part_quality_characteristics. short: 'S. Josupeit, S. Rüsenberg, N. Rupp, M. Gessler, H.-J. Schmid, in: 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014), 2014, pp. 2383–2385.' date_created: 2021-05-14T07:46:14Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: https://www.researchgate.net/publication/283135483_Thermal_ageing_of_polyamide_12_used_for_polymer_laser_sintering_-_Influence_on_part_quality_characteristics intvolume: ' 72' issue: '3' language: - iso: eng page: 2383-2385 publication: 72nd Annual Technical Conference of the Society of Plastics Engineers (ANTEC 2014) publication_identifier: isbn: - 978-1-634-39708-7 status: public title: Thermal ageing of polyamide 12 used for polymer laser sintering - influence on part quality characteristics type: conference user_id: '71545' volume: 72 year: '2014' ... --- _id: '22193' abstract: - lang: eng text: The process-related occurrence of varying cooling rates at different positions within the part cake is an important challenge regarding the part quality and reproducibility of the polymer laser sintering process. Temperature history dependent parameters are for example the part warpage, the crystallization behavior or powder ageing effects, which have to be considered for optimized process controls. Nevertheless, the inner temperature distribution and history during the cooling process is difficult to measure and less known yet. In this work, a Finite Element (FE) model is developed to understand and predict the temperature distribution and history within the part cake during the cooling process. Therefore, the thermal boundary conditions of a laser sintering system are analyzed and relevant parameters are identified. A basic FE model is set up in ABAQUS CAE software considering a part-free powder cake. Important thermal parameters of the bulk powder and the environment are adjusted and verified in relation to experimental in-process measured data. With this model it is possible to predict position-dependent cooling rates as a function of significant job parameters, for example the job height or the environmental conditions during the cooling phase. In combination with extended in-process temperature measurements and a consideration of built parts, this model will be an important tool for the development of optimized process controls. author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: L. full_name: Ordia, L. last_name: Ordia - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Ordia L, Schmid H-J. Development of a Basic Model to Simulate the Laser Sintering Cooling Process. In: International Conference on Additive Technologies. Vol 5. ; 2014:222-227. doi:https://www.researchgate.net/profile/Saeed_Khademzadeh2/publication/303022441_Geometrical_characterization_of_thin_walls_produced_by_micro_laser_sintering/links/5735cc7f08ae298602e08f1f/Geometrical-characterization-of-thin-walls-produced-by-micro-laser-sintering.pdf' apa: Josupeit, S., Ordia, L., & Schmid, H.-J. (2014). Development of a Basic Model to Simulate the Laser Sintering Cooling Process. In International Conference on Additive Technologies (Vol. 5, pp. 222–227). https://www.researchgate.net/profile/Saeed_Khademzadeh2/publication/303022441_Geometrical_characterization_of_thin_walls_produced_by_micro_laser_sintering/links/5735cc7f08ae298602e08f1f/Geometrical-characterization-of-thin-walls-produced-by-micro-laser-sintering.pdf bibtex: '@inproceedings{Josupeit_Ordia_Schmid_2014, title={Development of a Basic Model to Simulate the Laser Sintering Cooling Process}, volume={5}, DOI={https://www.researchgate.net/profile/Saeed_Khademzadeh2/publication/303022441_Geometrical_characterization_of_thin_walls_produced_by_micro_laser_sintering/links/5735cc7f08ae298602e08f1f/Geometrical-characterization-of-thin-walls-produced-by-micro-laser-sintering.pdf}, booktitle={International Conference on Additive Technologies}, author={Josupeit, Stefan and Ordia, L. and Schmid, Hans-Joachim}, year={2014}, pages={222–227} }' chicago: Josupeit, Stefan, L. Ordia, and Hans-Joachim Schmid. “Development of a Basic Model to Simulate the Laser Sintering Cooling Process.” In International Conference on Additive Technologies, 5:222–27, 2014. https://www.researchgate.net/profile/Saeed_Khademzadeh2/publication/303022441_Geometrical_characterization_of_thin_walls_produced_by_micro_laser_sintering/links/5735cc7f08ae298602e08f1f/Geometrical-characterization-of-thin-walls-produced-by-micro-laser-sintering.pdf. ieee: S. Josupeit, L. Ordia, and H.-J. Schmid, “Development of a Basic Model to Simulate the Laser Sintering Cooling Process,” in International Conference on Additive Technologies, 2014, vol. 5, pp. 222–227. mla: Josupeit, Stefan, et al. “Development of a Basic Model to Simulate the Laser Sintering Cooling Process.” International Conference on Additive Technologies, vol. 5, 2014, pp. 222–27, doi:https://www.researchgate.net/profile/Saeed_Khademzadeh2/publication/303022441_Geometrical_characterization_of_thin_walls_produced_by_micro_laser_sintering/links/5735cc7f08ae298602e08f1f/Geometrical-characterization-of-thin-walls-produced-by-micro-laser-sintering.pdf. short: 'S. Josupeit, L. Ordia, H.-J. Schmid, in: International Conference on Additive Technologies, 2014, pp. 222–227.' date_created: 2021-05-14T07:46:25Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: https://www.researchgate.net/profile/Saeed_Khademzadeh2/publication/303022441_Geometrical_characterization_of_thin_walls_produced_by_micro_laser_sintering/links/5735cc7f08ae298602e08f1f/Geometrical-characterization-of-thin-walls-produced-by-micro-laser-sintering.pdf intvolume: ' 5' language: - iso: eng page: 222-227 publication: International Conference on Additive Technologies publication_identifier: isbn: - 978-961-281-579-0 status: public title: Development of a Basic Model to Simulate the Laser Sintering Cooling Process type: conference user_id: '71545' volume: 5 year: '2014' ... --- _id: '22203' abstract: - lang: eng text: One barrier of laser sintering (LS) to become the main process for Direct Manufacturing (DM) is the surface quality of LS parts. Hence, the property which has to be improved is the rough surfaces of LS parts due to the layered structure. Another additional effect is the incomplete melting of powder particles on the surface due to the high process temperature. In this paper we demonstrate our approach of a theoretical model for the topography of LS part surfaces. We investigated the surface roughness as a function of surface orientation. Considering that the model involves further variables as layer thickness, particle density and particle size distribution to describe the topography precisely. Experimental results were used to optimize and check the results of the model. author: - first_name: Patrick full_name: Delfs, Patrick last_name: Delfs - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Delfs P, Schmid H-J. Simulation of the Surface Topography on Laser Sintered Polymer Parts. In: 25th Annual International Solid Freeform Fabrication Symposium. Vol 25. ; 2014:1250-1258. doi:http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf' apa: Delfs, P., & Schmid, H.-J. (2014). Simulation of the Surface Topography on Laser Sintered Polymer Parts. In 25th Annual International Solid Freeform Fabrication Symposium (Vol. 25, pp. 1250–1258). http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf bibtex: '@inproceedings{Delfs_Schmid_2014, title={Simulation of the Surface Topography on Laser Sintered Polymer Parts}, volume={25}, DOI={http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf}, booktitle={25th Annual International Solid Freeform Fabrication Symposium}, author={Delfs, Patrick and Schmid, Hans-Joachim}, year={2014}, pages={1250–1258} }' chicago: Delfs, Patrick, and Hans-Joachim Schmid. “Simulation of the Surface Topography on Laser Sintered Polymer Parts.” In 25th Annual International Solid Freeform Fabrication Symposium, 25:1250–58, 2014. http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf. ieee: P. Delfs and H.-J. Schmid, “Simulation of the Surface Topography on Laser Sintered Polymer Parts,” in 25th Annual International Solid Freeform Fabrication Symposium, 2014, vol. 25, pp. 1250–1258. mla: Delfs, Patrick, and Hans-Joachim Schmid. “Simulation of the Surface Topography on Laser Sintered Polymer Parts.” 25th Annual International Solid Freeform Fabrication Symposium, vol. 25, 2014, pp. 1250–58, doi:http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf. short: 'P. Delfs, H.-J. Schmid, in: 25th Annual International Solid Freeform Fabrication Symposium, 2014, pp. 1250–1258.' date_created: 2021-05-14T07:46:36Z date_updated: 2022-01-06T06:55:29Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/sites/default/files/2014-098-Delfs.pdf intvolume: ' 25' language: - iso: eng page: 1250-1258 publication: 25th Annual International Solid Freeform Fabrication Symposium status: public title: Simulation of the Surface Topography on Laser Sintered Polymer Parts type: conference user_id: '71545' volume: 25 year: '2014' ... --- _id: '22186' abstract: - lang: eng text: 'The reproducibility and reliability of quality aspects are an important challenge of the polymer laser sintering process. However, existing quality concepts and standardization activities considering influencing factors along the whole process chain have not been validated experimentally yet. In this work, these factors are analyzed and kept constant to obtain a reliable material data set for different layer thicknesses and testing temperatures. In addition, material qualities regarding powder ageing effects are analyzed using different build heights and layer thicknesses: while an increase of the layer thickness reduces mechanical part strength and density, it also results in a less intense thermal ageing of unmolten powder due to shorter build times.' article_number: '185374' author: - first_name: Stefan full_name: Rüsenberg, Stefan last_name: Rüsenberg - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid orcid: 000-0001-8590-1921 citation: ama: Rüsenberg S, Josupeit S, Schmid H-J. A method to characterize the quality of a polymer laser sintering process . Advances in Mechanical Engineering. 2014;6. doi:10.1155/2014/185374 apa: Rüsenberg, S., Josupeit, S., & Schmid, H.-J. (2014). A method to characterize the quality of a polymer laser sintering process . Advances in Mechanical Engineering, 6, Article 185374. https://doi.org/10.1155/2014/185374 bibtex: '@article{Rüsenberg_Josupeit_Schmid_2014, title={A method to characterize the quality of a polymer laser sintering process }, volume={6}, DOI={10.1155/2014/185374}, number={185374}, journal={Advances in Mechanical Engineering}, publisher={SAGE Publications}, author={Rüsenberg, Stefan and Josupeit, Stefan and Schmid, Hans-Joachim}, year={2014} }' chicago: Rüsenberg, Stefan, Stefan Josupeit, and Hans-Joachim Schmid. “A Method to Characterize the Quality of a Polymer Laser Sintering Process .” Advances in Mechanical Engineering 6 (2014). https://doi.org/10.1155/2014/185374. ieee: 'S. Rüsenberg, S. Josupeit, and H.-J. Schmid, “A method to characterize the quality of a polymer laser sintering process ,” Advances in Mechanical Engineering, vol. 6, Art. no. 185374, 2014, doi: 10.1155/2014/185374.' mla: Rüsenberg, Stefan, et al. “A Method to Characterize the Quality of a Polymer Laser Sintering Process .” Advances in Mechanical Engineering, vol. 6, 185374, SAGE Publications, 2014, doi:10.1155/2014/185374. short: S. Rüsenberg, S. Josupeit, H.-J. Schmid, Advances in Mechanical Engineering 6 (2014). date_created: 2021-05-14T07:46:17Z date_updated: 2026-02-19T14:21:49Z department: - _id: '150' - _id: '624' - _id: '219' doi: 10.1155/2014/185374 intvolume: ' 6' language: - iso: eng publication: Advances in Mechanical Engineering publication_identifier: issn: - 1687-8140 publisher: SAGE Publications status: public title: 'A method to characterize the quality of a polymer laser sintering process ' type: journal_article user_id: '14972' volume: 6 year: '2014' ... --- _id: '26129' abstract: - lang: eng text: Because of the large surface area of colloids interface effects are dominant in contrast to volume effects. The study presents experimental results of the direct transfer of magnetite nanoparticles from an aqueous to a non-miscible organic phase. The starting point is a water-based colloid that is synthesized through a precipitation reaction. The transfer is based on the adsorption of surfactants onto the particle surface at the liquid–liquid interface. While penetrating the liquid–liquid interface, the particles are covered with surfactants and a partial de-agglomeration is initiated. The intention is to produce a stable organic colloid, which has important applications in industry. The optimized process parameters for the successful phase transfer process, the adsorption reactions at the liquid–liquid interface and the stabilization of primary particles in the organic phase are demonstrated. author: - first_name: Jacqueline full_name: Erler, Jacqueline last_name: Erler - first_name: Stefanie full_name: Machunsky, Stefanie last_name: Machunsky - first_name: Philipp full_name: Grimm, Philipp last_name: Grimm - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid - first_name: Urs A. full_name: Peuker, Urs A. last_name: Peuker citation: ama: Erler J, Machunsky S, Grimm P, Schmid H-J, Peuker UA. Liquid–liquid phase transfer of magnetite nanoparticles — Evaluation of surfactants. Powder Technology. 2013;247:265-269. doi:10.1016/j.powtec.2012.09.047 apa: Erler, J., Machunsky, S., Grimm, P., Schmid, H.-J., & Peuker, U. A. (2013). Liquid–liquid phase transfer of magnetite nanoparticles — Evaluation of surfactants. Powder Technology, 247, 265–269. https://doi.org/10.1016/j.powtec.2012.09.047 bibtex: '@article{Erler_Machunsky_Grimm_Schmid_Peuker_2013, title={Liquid–liquid phase transfer of magnetite nanoparticles — Evaluation of surfactants}, volume={247}, DOI={10.1016/j.powtec.2012.09.047}, journal={Powder Technology}, author={Erler, Jacqueline and Machunsky, Stefanie and Grimm, Philipp and Schmid, Hans-Joachim and Peuker, Urs A.}, year={2013}, pages={265–269} }' chicago: 'Erler, Jacqueline, Stefanie Machunsky, Philipp Grimm, Hans-Joachim Schmid, and Urs A. Peuker. “Liquid–Liquid Phase Transfer of Magnetite Nanoparticles — Evaluation of Surfactants.” Powder Technology 247 (2013): 265–69. https://doi.org/10.1016/j.powtec.2012.09.047.' ieee: 'J. Erler, S. Machunsky, P. Grimm, H.-J. Schmid, and U. A. Peuker, “Liquid–liquid phase transfer of magnetite nanoparticles — Evaluation of surfactants,” Powder Technology, vol. 247, pp. 265–269, 2013, doi: 10.1016/j.powtec.2012.09.047.' mla: Erler, Jacqueline, et al. “Liquid–Liquid Phase Transfer of Magnetite Nanoparticles — Evaluation of Surfactants.” Powder Technology, vol. 247, 2013, pp. 265–69, doi:10.1016/j.powtec.2012.09.047. short: J. Erler, S. Machunsky, P. Grimm, H.-J. Schmid, U.A. Peuker, Powder Technology 247 (2013) 265–269. date_created: 2021-10-13T14:24:52Z date_updated: 2022-01-06T06:57:16Z doi: 10.1016/j.powtec.2012.09.047 intvolume: ' 247' language: - iso: eng page: 265-269 publication: Powder Technology publication_identifier: issn: - 0032-5910 publication_status: published status: public title: Liquid–liquid phase transfer of magnetite nanoparticles — Evaluation of surfactants type: journal_article user_id: '70093' volume: 247 year: '2013' ... --- _id: '26130' abstract: - lang: eng text: 'Zur Erfüllung der Anforderungen der novellierten ersten Bundesimmissionsschutzverordnung (1. BImSchV: Verordnung über kleine und mittlere Feuerungsanlagen) wurde ein Schlauchfiltersystem für den Gebrauch in kleinen und mittleren Feuerungsanlagen entwickelt. Ein zur Filtration benötigtes Filterhilfsmittel wird vollautomatisch portioniert, dispergiert und dem Prozess zugeführt. Mit dieser Technik ist es möglich, den Feinstaubgehalt im Abgas auf unter 1 mg m^3 i.N. zu senken und damit die geforderten Grenzwerte weit zu unterschreiten. ' author: - first_name: Sascha full_name: Schiller, Sascha last_name: Schiller - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: Schiller S, Schmid H-J. Hocheffiziente Feinstaubabscheidung aus Kleinfeuerungsanlagen mit einem Schlauchfilter. Chemie Ingenieur Technik. Published online 2013:1324-1328. doi:10.1002/cite.201200114 apa: Schiller, S., & Schmid, H.-J. (2013). Hocheffiziente Feinstaubabscheidung aus Kleinfeuerungsanlagen mit einem Schlauchfilter. Chemie Ingenieur Technik, 1324–1328. https://doi.org/10.1002/cite.201200114 bibtex: '@article{Schiller_Schmid_2013, title={Hocheffiziente Feinstaubabscheidung aus Kleinfeuerungsanlagen mit einem Schlauchfilter}, DOI={10.1002/cite.201200114}, journal={Chemie Ingenieur Technik}, author={Schiller, Sascha and Schmid, Hans-Joachim}, year={2013}, pages={1324–1328} }' chicago: Schiller, Sascha, and Hans-Joachim Schmid. “Hocheffiziente Feinstaubabscheidung Aus Kleinfeuerungsanlagen Mit Einem Schlauchfilter.” Chemie Ingenieur Technik, 2013, 1324–28. https://doi.org/10.1002/cite.201200114. ieee: 'S. Schiller and H.-J. Schmid, “Hocheffiziente Feinstaubabscheidung aus Kleinfeuerungsanlagen mit einem Schlauchfilter,” Chemie Ingenieur Technik, pp. 1324–1328, 2013, doi: 10.1002/cite.201200114.' mla: Schiller, Sascha, and Hans-Joachim Schmid. “Hocheffiziente Feinstaubabscheidung Aus Kleinfeuerungsanlagen Mit Einem Schlauchfilter.” Chemie Ingenieur Technik, 2013, pp. 1324–28, doi:10.1002/cite.201200114. short: S. Schiller, H.-J. Schmid, Chemie Ingenieur Technik (2013) 1324–1328. date_created: 2021-10-13T14:27:15Z date_updated: 2022-01-06T06:57:16Z doi: 10.1002/cite.201200114 language: - iso: eng page: 1324-1328 publication: Chemie Ingenieur Technik publication_identifier: issn: - 0009-286X publication_status: published status: public title: Hocheffiziente Feinstaubabscheidung aus Kleinfeuerungsanlagen mit einem Schlauchfilter type: journal_article user_id: '70093' year: '2013' ... --- _id: '22175' abstract: - lang: eng text: 'In this work, the quality of laser sintered parts is investigated along a defined process chain for a nylon 12 material (PA 2200) on an EOSINT P395 laser sintering system. Important influencing factors are figured out. Rheological powder characterization methods are investigated as well as mechanical, physical and other chosen part properties. The concept allows reproducible part quality characteristics and is used to obtain (testing) temperature dependent material data. It can also be extended on further materials based on nylon 12: PA 2241 FR, which is convenient for the aircraft industry due to its flame-retardant properties, and PA 2221, which has economic advantages due to a lower material consumption.' author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: Stefan full_name: Rüsenberg, Stefan last_name: Rüsenberg - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Rüsenberg S, Schmid H-J. A material-based quality concept for polymer laser sintering. In: 24th Annual International Solid Freeform Fabrication Symposium . Vol 24. ; 2013:44-54. doi:http://utw10945.utweb.utexas.edu/Manuscripts/2013/2013-03-Josupeit.pdf' apa: Josupeit, S., Rüsenberg, S., & Schmid, H.-J. (2013). A material-based quality concept for polymer laser sintering. In 24th Annual International Solid Freeform Fabrication Symposium (Vol. 24, pp. 44–54). http://utw10945.utweb.utexas.edu/Manuscripts/2013/2013-03-Josupeit.pdf bibtex: '@inproceedings{Josupeit_Rüsenberg_Schmid_2013, title={A material-based quality concept for polymer laser sintering}, volume={24}, DOI={http://utw10945.utweb.utexas.edu/Manuscripts/2013/2013-03-Josupeit.pdf}, booktitle={24th Annual International Solid Freeform Fabrication Symposium }, author={Josupeit, Stefan and Rüsenberg, Stefan and Schmid, Hans-Joachim}, year={2013}, pages={44–54} }' chicago: Josupeit, Stefan, Stefan Rüsenberg, and Hans-Joachim Schmid. “A Material-Based Quality Concept for Polymer Laser Sintering.” In 24th Annual International Solid Freeform Fabrication Symposium , 24:44–54, 2013. http://utw10945.utweb.utexas.edu/Manuscripts/2013/2013-03-Josupeit.pdf. ieee: S. Josupeit, S. Rüsenberg, and H.-J. Schmid, “A material-based quality concept for polymer laser sintering,” in 24th Annual International Solid Freeform Fabrication Symposium , 2013, vol. 24, pp. 44–54. mla: Josupeit, Stefan, et al. “A Material-Based Quality Concept for Polymer Laser Sintering.” 24th Annual International Solid Freeform Fabrication Symposium , vol. 24, 2013, pp. 44–54, doi:http://utw10945.utweb.utexas.edu/Manuscripts/2013/2013-03-Josupeit.pdf. short: 'S. Josupeit, S. Rüsenberg, H.-J. Schmid, in: 24th Annual International Solid Freeform Fabrication Symposium , 2013, pp. 44–54.' date_created: 2021-05-14T07:46:04Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: http://utw10945.utweb.utexas.edu/Manuscripts/2013/2013-03-Josupeit.pdf intvolume: ' 24' language: - iso: eng page: 44-54 publication: '24th Annual International Solid Freeform Fabrication Symposium ' status: public title: A material-based quality concept for polymer laser sintering type: conference user_id: '71545' volume: 24 year: '2013' ... --- _id: '22192' abstract: - lang: eng text: Laser Sintering is a powder based additive manufacturing technology. The amount of used powder, which is not sintered, can be refreshed and used for further building jobs. Due to cost reduction, better mechanical properties and a simpler processing it is reasonable to combine virgin and used powder for part manufacturing. During the building time the powder is thermally loaded and its structure is changed. State of the art in laser sintering is a defined powder ratio. Since the powder ageing depends on the individual history of sintering, this procedure cannot ensure a defined powder quality. However, for a serial production it is necessary to characterize the raw material, as well as all other steps along the process chain, in order to ensure a high reproducibility and reliability. Rheological, physical and particle properties are considered to correlate powder and chosen material properties. Different powder qualities adjusted by the Melt Volume Rate (MVR) are tested using promising rheological properties like viscosity or molecular weight. Investigations about powder bed density, bulk properties as well as thermal characterization complement the experimental setup. These parameters are correlated with mechanical, electrical, thermal and physical material properties of laser sintered parts. The most important influencing factors along the process chain are kept constant. At the end a procedure is shown to obtain a defined powder quality. This procedure will be transferred to other materials and will be tested using other laser sintering machines of the same type as well as other types. author: - first_name: Stefan full_name: Rüsenberg, Stefan last_name: Rüsenberg - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Rüsenberg S, Schmid H-J. Advanced characterization method of Nylon 12 materials for application in laser sinter processing. In: International Conference of the Polymer-Processing-Society (PPS). Vol 29. ; 2013. doi:10.1063/1.4873877' apa: Rüsenberg, S., & Schmid, H.-J. (2013). Advanced characterization method of Nylon 12 materials for application in laser sinter processing. In International Conference of the Polymer-Processing-Society (PPS) (Vol. 29). https://doi.org/10.1063/1.4873877 bibtex: '@inproceedings{Rüsenberg_Schmid_2013, title={Advanced characterization method of Nylon 12 materials for application in laser sinter processing}, volume={29}, DOI={10.1063/1.4873877}, booktitle={International Conference of the Polymer-Processing-Society (PPS)}, author={Rüsenberg, Stefan and Schmid, Hans-Joachim}, year={2013} }' chicago: Rüsenberg, Stefan, and Hans-Joachim Schmid. “Advanced Characterization Method of Nylon 12 Materials for Application in Laser Sinter Processing.” In International Conference of the Polymer-Processing-Society (PPS), Vol. 29, 2013. https://doi.org/10.1063/1.4873877. ieee: S. Rüsenberg and H.-J. Schmid, “Advanced characterization method of Nylon 12 materials for application in laser sinter processing,” in International Conference of the Polymer-Processing-Society (PPS), 2013, vol. 29. mla: Rüsenberg, Stefan, and Hans-Joachim Schmid. “Advanced Characterization Method of Nylon 12 Materials for Application in Laser Sinter Processing.” International Conference of the Polymer-Processing-Society (PPS), vol. 29, 2013, doi:10.1063/1.4873877. short: 'S. Rüsenberg, H.-J. Schmid, in: International Conference of the Polymer-Processing-Society (PPS), 2013.' date_created: 2021-05-14T07:46:24Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: 10.1063/1.4873877 intvolume: ' 29' language: - iso: eng publication: International Conference of the Polymer-Processing-Society (PPS) status: public title: Advanced characterization method of Nylon 12 materials for application in laser sinter processing type: conference user_id: '71545' volume: 29 year: '2013' ... --- _id: '22197' author: - first_name: Stefan full_name: Josupeit, Stefan last_name: Josupeit - first_name: Stefan full_name: Rüsenberg, Stefan last_name: Rüsenberg - first_name: Hans-Joachim full_name: Schmid, Hans-Joachim id: '464' last_name: Schmid citation: ama: 'Josupeit S, Rüsenberg S, Schmid H-J. Mechanische und rheologische Untersuchungen neuer Laser Sinter Materialien. In: Merseburger Rapid Prototyping Forum. Vol 7. ; 2013. doi:https://www.rp-netzwerk.de/images/stories/pdf/rapid_7/Universitaet_Paderborn_DMRC_RP-Forum2013.pdf' apa: Josupeit, S., Rüsenberg, S., & Schmid, H.-J. (2013). Mechanische und rheologische Untersuchungen neuer Laser Sinter Materialien. In Merseburger Rapid Prototyping Forum (Vol. 7). https://www.rp-netzwerk.de/images/stories/pdf/rapid_7/Universitaet_Paderborn_DMRC_RP-Forum2013.pdf bibtex: '@inproceedings{Josupeit_Rüsenberg_Schmid_2013, title={Mechanische und rheologische Untersuchungen neuer Laser Sinter Materialien}, volume={7}, DOI={https://www.rp-netzwerk.de/images/stories/pdf/rapid_7/Universitaet_Paderborn_DMRC_RP-Forum2013.pdf}, booktitle={Merseburger Rapid Prototyping Forum}, author={Josupeit, Stefan and Rüsenberg, Stefan and Schmid, Hans-Joachim}, year={2013} }' chicago: Josupeit, Stefan, Stefan Rüsenberg, and Hans-Joachim Schmid. “Mechanische Und Rheologische Untersuchungen Neuer Laser Sinter Materialien.” In Merseburger Rapid Prototyping Forum, Vol. 7, 2013. https://www.rp-netzwerk.de/images/stories/pdf/rapid_7/Universitaet_Paderborn_DMRC_RP-Forum2013.pdf. ieee: S. Josupeit, S. Rüsenberg, and H.-J. Schmid, “Mechanische und rheologische Untersuchungen neuer Laser Sinter Materialien,” in Merseburger Rapid Prototyping Forum, 2013, vol. 7. mla: Josupeit, Stefan, et al. “Mechanische Und Rheologische Untersuchungen Neuer Laser Sinter Materialien.” Merseburger Rapid Prototyping Forum, vol. 7, 2013, doi:https://www.rp-netzwerk.de/images/stories/pdf/rapid_7/Universitaet_Paderborn_DMRC_RP-Forum2013.pdf. short: 'S. Josupeit, S. Rüsenberg, H.-J. Schmid, in: Merseburger Rapid Prototyping Forum, 2013.' date_created: 2021-05-14T07:46:29Z date_updated: 2022-01-06T06:55:28Z department: - _id: '150' - _id: '624' - _id: '219' doi: https://www.rp-netzwerk.de/images/stories/pdf/rapid_7/Universitaet_Paderborn_DMRC_RP-Forum2013.pdf intvolume: ' 7' language: - iso: eng publication: Merseburger Rapid Prototyping Forum status: public title: Mechanische und rheologische Untersuchungen neuer Laser Sinter Materialien type: conference user_id: '71545' volume: 7 year: '2013' ...