Structure Development of Semi-crystalline Polymers in Laser Based Powder Bed Fusion

Cholewa S, Jaksch A, Drummer D (2023)

Publication Language: English

Publication Type: Conference contribution, Conference Contribution

Publication year: 2023

Event location: Denver, Colorado US

Abstract

The impact of melt hardening at low melt undercooling and under atmospheric pressure creates boundary conditions that have yet to be extensively studied since traditional techniques do not require such information. However, for powder bed fusion of polymers, the transition from the melt after exposure to an elastically dominant melt is critical as the crystallization in the building phase occurs under these conditions yielding stresses due to crystallization volume shrinkage. As a result, a process-adapted evaluation is required to determine how long the molten polymer remains viscously dominant, and the point where the stresses are stored in the melt. Therefore, the crystallization of a semi-crystalline melt is investigated in this work using rheological data in conjunction with FTIR microscopy. A modified measurement setup of the rheometer with an ATR crystal allows a simultaneous description of crystallization by FTIR spectroscopy and measurement of the rheological behavior of the material. A comparison between the different techniques indicates that the increase in viscoelastic properties during crystallization begins at low degrees of crystallinity. It is determined that the solidification of the melt is detectable at relatively low degrees of crystallization conversion, and that no stresses are accumulated in the material until this point.

Authors with CRIS profile

Simon Cholewa Lehrstuhl für Kunststofftechnik Andreas Jaksch Lehrstuhl für Kunststofftechnik Dietmar Drummer Lehrstuhl für Kunststofftechnik

Related research project(s)

Process-adapted material characterization for laser beam melting (A3) (SFB 814 (A3)) CRC 814 - Additive Manufacturing (SFB 814) July 1, 2011 - June 30, 2023

How to cite

APA:

Cholewa, S., Jaksch, A., & Drummer, D. (2023). Structure Development of Semi-crystalline Polymers in Laser Based Powder Bed Fusion. In Proceedings of the Antec 2023. Denver, Colorado, US.

MLA:

Cholewa, Simon, Andreas Jaksch, and Dietmar Drummer. "Structure Development of Semi-crystalline Polymers in Laser Based Powder Bed Fusion." Proceedings of the Antec 2023, Denver, Colorado 2023.

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