Modelling of the Aging Behavior of Polyamide 12 Powder during Laser Melting Process

Beitrag bei einer Tagung


Details zur Publikation

Autorinnen und Autoren: Drummer D, Wudy K, Drexler M
Jahr der Veröffentlichung: 2015
Tagungsband: Proceedings of the Polymer Processing Society 30th Annual Meeting
Seitenbereich: 5
ISSN: 0094-243X
Sprache: Englisch


Abstract


Concerning individualization, the requirements to products have increased. Additive manufacturing technologies, such as selective laser melting allow manufacturing of complex parts without tools and forms. Due to this additive manufacturing processes comply, in opposite to conventional techniques, with these increased demands on processing technology. Due to the high temperature during processing, a degradation of the used plastic powder occurs. The non-molten material in the building chamber, the so-called partcake, can be removed after building from the finished component and reused for another process. To realize reproducible part properties refreshing of pancake powder with 30 up to 50 % virgin powder is necessary. However, these refreshing strategies lead to varying component properties due to an undefined aging state. Previous investigations on oven aged powder for selective laser melting showed for short periods of storage near the melting point thermally induced post condensation is the predominate aging effect. Due to post condensation the molecular weight and thus the viscosity increases. This paper focuses on the modeling of the post condensation process to define the aging state of polyamide 12 powder in laser melting process. Therefore the rheological behavior of PA 12 powder in dependency of time and temperature is investigated. Isothermal viscosity measurements are conducted in order to describe the post condensation reaction with a model. With knowledge of the kinetics of the post condensation reaction the state of aging can be predicted in a second step. Thus expected useful life of the powder can be calculated in dependency of the building chamber temperature. These results are then compared with viscosity values of defined aged PA 12 powder to validate the determined model.



FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Drexler, Maximilian
Sonderforschungsbereich 814/3 Additive Fertigung
Drummer, Dietmar Prof. Dr.-Ing.
Lehrstuhl für Kunststofftechnik
Wudy, Katrin Dr.-Ing.
Sonderforschungsbereich 814/3 Additive Fertigung


Zitierweisen

APA:
Drummer, D., Wudy, K., & Drexler, M. (2015). Modelling of the Aging Behavior of Polyamide 12 Powder during Laser Melting Process. In Proceedings of the Polymer Processing Society 30th Annual Meeting (pp. 5). Cleveland, USA.

MLA:
Drummer, Dietmar, Katrin Wudy, and Maximilian Drexler. "Modelling of the Aging Behavior of Polyamide 12 Powder during Laser Melting Process." Proceedings of the 30th Annual Meeting of the Polymer Processing Society, Cleveland, USA 2015. 5.

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Zuletzt aktualisiert 2018-08-08 um 00:53