Topological design for 3D-printing of carbon fibre reinforced composite structural parts

Abstract

This study develops a novel procedure combining topological design and fibre placement paths based on average load transmission trajectories for high load-bearing capacity of 3D-printed carbon fibre reinforced composite parts. First, a two-stage topological design procedure is established to acquire the optimal topology for confining maximum stress and minimising structural compliance. Second, based on calculations for the average load transmission trajectories within the optimal topology, continuous carbon fibre placement paths are defined for 3D-printing with fused filament fabrication (FFF). Experimental studies are performed for topologically designed short cantilever and three-point-bending specimens to characterise the reinforcement effect of short carbon fibre (SCF, vol% = 15%) and continuous carbon fibre (CCF, vol% = 35%) on specimens printed with pure polyamide (PA). The CCF increases the stiffness and the magnitude of peak load of the cantilever specimens by 1198% and 1633%, respectively, while the increments are 569% and 293%, respectively, for three-point-bending specimens, showing the significant impact of the procedure. The SCF also increases the stiffness and peak load of the both structural configurations but to a much lesser degree.