Low-velocity impact behavior assessment of 3D printed sandwiched structure with varying infill patterns

Abstract

Low-velocity impact behavior poses a significant challenge to the structural integrity of 3D-printed sandwich composites, often leading to damage mechanisms such as fiber failure, matrix cracking, and delamination. Understanding the impact resistance and energy absorption capacity of these composites is crucial for optimizing their performance in practical applications. The primary objective of this research is to analyze the forcedisplacement and force-time responses of 3D-printed sandwich structures with PLA and ABS cores and woven roving face sheets under varying impact energies (15J, 30J, and 45J). Three infill patterns Grid, Cross3D, and Lightning were used to explore the relationship between structural stiffness, damage initiation, and energy dissipation. The Grid pattern in PLA with top layers exhibited the highest stiffness and peak force, demonstrating superior resistance to internal damage and deformation. In contrast, ABS with Lightning infill showed the lowest peak force and highest deformation, indicating early failure under high-energy impacts. SEM, microscopy and 3D scanning revealed extensive damage mechanisms, particularly in high-energy impacts, with PLA Grid with top layers displaying the best energy absorption and structural resilience. This research highlights the critical role of material type and infill pattern in enhancing the impact resistance of 3D-printed sandwich composites and provides valuable insights for future applications.