Functional behavior and energy absorption characteristics of additively manufactured smart sandwich structures

Additive manufacturing (AM) of functional parts using smart materials has attracted considerable interest in both scientific and industrial domains. The application of shape memory polymers (SMPs) opens up new possibilities in the fabrication process and makes them able to recover their initial shape after deformation. This study aims to demonstrate the synergic potentiality of the SMPs in fused filament fabrication (FFF) to manufacture 4D printed smart sandwiches and address their functional behavior. This technological solution promises lightweight and biodegradable parts, which boast exceedingly valuable performance in reusable energy absorbing applications. Several designs, materials, and process parameters including nozzle temperature, layer height, and printing speed are investigated in this work. The results show that selecting the appropriate core geometries could enhance the mechanical strength as well as the deformation capability in the sandwich structures. Likewise, the applied materials considerably affect the energy absorption characteristics. Moreover, tweaking the process parameters is found to be a useful approach for maximizing the mechanical properties and displacement in the 4D-printed sandwiches.