Investigation of continuous fiberglass reinforcement on additively manufactured primitive scaffolds

Abstract Fused Filament Fabrication is an Additive Manufacturing technology that allows continuous fiber reinforcement to be incorporated into printed parts during manufacturing. Materials like short carbon fiber reinforced Polyamide 6 serve as matrix material between the continuous fibers, resulting in a superposition of continuous and short fiber reinforcement. This facilitates the production of lightweight components with high rigidity and strength. Furthermore, Additive Manufacturing enables the integration of complex geometries like Triply Periodic Minimal Surface structures. The combination of these structures with a strategic fiber reinforcement offers the potential for substantial improvement in mechanical properties. This study presents a strategy for optimized integration of continuous fiberglass into Fused Filament Fabrication-printed primitive Triply Periodic Minimal Surface. The objective was to achieve a maximum enhancement in mechanical properties and optimal manufacturability. Finite Element Simulations indicated that the necks of the structures were regions experiencing significant stress concentration, which was addressed with the strategical positioning of continuous fiber along these areas. Morphological and thermal analyses were conducted to determine optimal printing conditions for processing the feedstock materials. The printed structures were analyzed by scanning electron microscopy and the effectiveness of the fiber reinforcement was demonstrated by compression tests. The strategic placement of the continuous fiberglass resulted in an increase in maximum strength of Δ σ max = 185% and in Young’s modulus of Δ E = 95%. Furthermore, an increase in absorbed energy capacity of Δ W = 123% and in crushing strength of Δ σ c = 94% at the first peak were measured. The results show the considerable potential of selective continuous fiberglass integration into Triply Periodic Minimal Surface structures. The substantial improvement of the mechanical properties suggests that material can be reduced and thereby enable the production of significantly lighter and more sustainable components.