AM Science forum Rapid.Tech 3D 2024

Investigation of Interfacial Shear Strength of Hybrid Fiber-Reinforced Polyamide Composite Structures

The Fraunhofer Institute for Microstructure of Materials and Systems IMWS specialises in structures produced using the Fused Granulate Fabrication (FGF) process. Dr Ralf Schlimper talks about the findings.

Fused Granular Fabrication (FGF), a technology within the framework of Large Format Additive Manufacturing (LFAM), focuses on cost-effective granulate-based manufacturing, eliminating the need for semi-finished filaments. The anisotropic behaviour of 3D printed parts is evident in their varying mechanical properties along different axes which is amplified when fibers are incorporated into the material. In this study a significant improvement of the flexural stiffness and strength of manufactured FGF structures and a lowering of anisotropic behaviour has been reached through the integration of continuous fiber-reinforced unidirectional tapes (UD-tapes). With the employment of Automated Tape Laying (ATL) UD-tapes had been applied to plate structures manufactured by FGF process. The manufactured structures were characterized in terms of their morphology and mechanical behaviour by 3-point-bending tests. As the effectiveness of the UD-tape reinforcement requires sufficient bonding between the UD-tape and the FGF structure, the interface morphology and interface strength was investigated. Different surface preparations were considered prior to the tape laying process step to account for the influence of the surface quality of FGF structures. It was demonstrated that UD-tape laying on a FGF surface that was prepared by a milling process provides the higher interface shear strength compared to an untreated FGF surface.

Presentation language: ENG

Speakers (1)

Dr.-Ing. Ralf Schlimper

Dr.-Ing. Ralf Schlimper

Research associate