Targeted Temperature Manipulation and Analysis of the Influence on Mechanical Properties in Large-Scale Extrusion Additive Manufacturing

Applied Sciences

Tim A. Osswald¹  Nevine Tagscherer²  Klaus Drechsler² 

[1] Department of Mechanical Engineering, Polymer Engineering Center, University of Wisconsin-Madison, 1513 University Ave., Madison, WI 52706, USA;TUM School of Engineering and Design, Department of Mechanical Engineering, Chair of Carbon Composites, Technical University of Munich, Boltzmannstraße 15, 85748 Garching bei Muenchen, Germany;

关键词: composites;    fusion bonding;    mechanical testing;    3D printing;    extrusion;   

DOI  :  10.3390/app12062998

来源: DOAJ

【 摘 要 】

Layer times in large-scale Extrusion Additive Manufacturing (EAM) of carbon fiber-reinforced thermoplastics are often outside the recommended process window. Brief layer times of tall parts with short path lengths lead to high temperatures and thus to melting of the component. In contrast, the substrate temperature decreases too far at longer layer times to achieve sufficient fusion bonding through molecular diffusion across the interface. Heating by infrared emitters and cooling by compressed air were experimentally tested and evaluated as methods for temperature control. Assuming that bond formation is mainly temperature-controlled, mechanical properties were expected to be similar to those of non-manipulated samples at the same temperatures. Samples of short carbon fiber-filled polyamide 6 in pellet form were manufactured in three test series. Infrared heating resulted in comparable tensile properties to samples at the target temperature and in a significant increase compared to the base temperature without heating. Cooling proved to be more effective when closer to the deposition nozzle, with tensile results even exceeding the expected values at temperatures below 170 °C. Overall, the results support the potential for targeted temperature control in EAM and the hypothesis that comparable bond strength can be achieved in dependence of the final substrate temperature.

【 授权许可】

Unknown