Low‐velocity impact performance of fused‐deposition‐modelling‐manufactured carbon‐fibre‐faced sandwich panels with novel double arrowhead core architectures

Lightweight sandwich structures with excellent impact energy absorption (EA) are important for applications needing a mix of low mass and impact resistance. The aim of this investigation is to evaluate the low‐velocity impact behaviour of four new double‐arrowhead core geometries fabricated using fused deposition modelling and sandwiched between carbon‐fibre face‐sheets. The purpose was to study the influence of the core geometry consisting of the circular nodal and truss‐supported features on the impact response and EA characteristics. The carbon‐fibre‐reinforced polylactic acid cores were printed under the same fused deposition modelling conditions. Low‐velocity drop‐weight impact tests were performed on them at an impact energy of about 46.6 J with all the other testing parameters kept unchanged. The EA was calculated using the area under force–displacement curves acquired experimentally. Specific energy absorption (SEA) and EA efficiency were also examined for comparison. Among the four configurations, the TSDAHSWCN had the maximum EA of 39.54 J, SEA of 211.46 J kg −1 and EA efficiency of 84.85%. The improved performance is due to the synergistic effect of the truss‐supported double‐arrowhead topology, solid‐filled circular nodal areas and associated load‐transfer and deformation characteristics. These results show the potential for TSDAHSWCN to be a promising effective impact energy absorbing core design for lightweight sandwich structures. However, the current results are confined to the impact condition explored and need to be further evaluated for a wider range of impact energy and application‐specific loading circumstances before applicability to specific aerospace or automotive applications can be demonstrated.