ISBN 9783843952972

978-3-8439-5297-2, Reihe Ingenieurwissenschaften

Nevine Tagscherer
Interdisciplinary mechatronic consideration of large-scale carbon fiber reinforced extrusion additive manufacturing

212 Seiten, Dissertation Technische Universität München (2022), Softcover, A5

Zusammenfassung / Abstract

Extrusion additive manufacturing (EAM) of thermoplastic composites is a promising technology for automotive prototyping. However, there is a gap in research and manufacturing for large-scale, thin-walled parts with high strength comparable to injection molded components. This study aimed to develop a process for short carbon fiber filled polyamide 6 and investigate its mechanical performance.

A prototype extrusion unit was developed and a stable and reproducible process was achieved. Material characterizations and process analyses identified key manufacturing parameters and their influence on mechanical behavior. Thermal, flow, and finite element analyses were used to model part behavior, enabling effective component design. The analyses revealed a directional bias in the build direction, which could be reduced by manipulating substrate temperatures. Initial temperature manipulation resulted in improved bond strength and shape retention, showing potential for further development of heating and cooling options.

The study lays the foundation for incorporating large-scale EAM into automotive prototyping. The methodologies developed can be applied to other thermoplastics and processes for qualification and comparison. While the process and equipment were suitable for most planar-sliced large-scale components, free-form capability was limited. Further investigations, possibly with CNC-controlled robotic systems, are necessary to achieve true freeform capability with dimensional accuracy.