Concept development to include continuous reinforcing fibres into the selective laser sintering process

Abstract

This work is part of a long-term project at the WBK to develop a SLS printer which can automatically incorporate the manufactured parts with a continuous fibre-reinforcement. The investigations done here mark an early stage in the design with this thesis being the second scientific work to contribute to this project.

The objective was to develop a concept for the fibre module in the printer. Therefore, the SLS process was split into its basic steps and subfunctions, the fibre introduction was modelled on this theoretical level and all the relevant points of interaction were defined. These were fed into a morphological analysis and made up most of the parameters in the morphological box. For each parameter a set of values or technical implementations were designed and with the help of a Sintratec Kit printer the main solutions were validated. The findings of these test series led into a revise of the morphological box and this second iteration was put through a Cross-Consistency Assessment to rule out all internal contradictions and reduce the number of possible parameter combinations. Finally, the concept that provided the best ratio between highest complexity in the archivable fibre path and the lowest complexity in the technical implementation was selected and presented.

The next steps towards the final machine will be to build up the fibre module in a CAD program and design all the components. After the manufacturing and integration into a SLS printer the whole set up needs to be characterized and adequate materials have to be selected.