Additive manufacturing and mechanical performance of carbon fiber reinforced Polyamide-6 composites

Aerospace and automotive industries always quest for materials with higher strength-to-weight ratios, as material usage significantly reduces while designing functional components. The design of laminated structures with different core structures is usually practiced to develop lightweight parts. Additive manufacturing (AM) processes have gained significant attention in these industrial structures, owing to flexibility in the design and fabrication of complex core structures. Therefore, it is essential to manufacture and characterize the lightweight structures fabricated through AM processes for better adaptability in such applications. This study reports the experimental investigations on the effect of infill patterns and infill densities on the mechanical performance of additively manufactured carbon fiber-reinforced polyamide-6 (PA6) composites. Sandwich structures with different core designs (namely, triangular, hexagonal, rectangular) and infill densities (varying 18–62%) were fabricated using the fused filament fabrication (FFF) process. The additively manufactured tensile testing coupons were tested using the universal testing machine. Both infill patterns and infill densities significantly influenced the mechanical behavior of 3D-printed composites. It is concluded that triangular and hexagonal infill patterns performed better at lower infill densities, while rectangular infill patterns provided better mechanical strength and elongation at higher infill densities. However, if material saving is the priority, hexagonal patterns are preferred.